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Sample records for chalcopyrite

  1. Ternary chalcopyrite semiconductors

    CERN Document Server

    Shay, J L; Pamplin, B R

    2013-01-01

    Ternary Chalcopyrite Semiconductors: Growth, Electronic Properties, and Applications covers the developments of work in the I-III-VI2 and II-IV-V2 ternary chalcopyrite compounds. This book is composed of eight chapters that focus on the crystal growth, characterization, and applications of these compounds to optical communications systems. After briefly dealing with the status of ternary chalcopyrite compounds, this book goes on describing the crystal growth of II-IV-V2 and I-III-VI2 single crystals. Chapters 3 and 4 examine the energy band structure of these semiconductor compounds, illustrat

  2. Effects of microorganisms on surface properties of chalcopyrite and bioleaching

    Institute of Scientific and Technical Information of China (English)

    CHEN Ming-lian; ZHANG Lin; GU Guo-hua; HU Yue-hua; SU Li-jun

    2008-01-01

    The alteration of surface properties of chalcopyrite after biological conditioning with Acidithiobacillus ferrooxidans and Acidithiobacillus caldus was evaluated by Zeta-potential,adsorption studies,FT-IR spectra and contact angle measurement.The Zeta-potential studies show that the iso-electric point(IEP) of chalcopyrite after bacterial treatment moves towards the IEP of pure cells,indicating the adsorption of cells on chalcopyrite surface.The FT-IR spectra of chalcopyrite treated with bacterial cells show the presence of the cell functional groups signifying cells adsorption.Due to the formation of elemental sulfur and intermediate copper sulphides on chalcopyrite surface,the contact angle and surface hydrophobicity of chalcopyrite increase at the initial bioleaching stage.Chalcopyrite bioleaching by Acidithiobacillus ferrooxidans has higher copper extraction,which agrees with the fact that Acidithiobacillus ferrooxidans adsorbed on chalcopyrite surface is much more than Acidithiobacillus caldus.The results support the direct mechanism of sulfide oxidations in bioleaching chalcopyrite.

  3. Influences of silver sulfide on the bioleaching of chalcopyrite, pyrite and chalcopyrite-containing ore

    Institute of Scientific and Technical Information of China (English)

    胡岳华; 王军; 邱冠周; 王淀佐

    2002-01-01

    The effects of silver sulfide (Ag2S) on the bioleaching of chalcopyrite and pyrite were investigated in this paper. It has been shown that Ag2S enhanced the yields of bioleaching of chalcopyrite but inhibited the bio-oxidation of pyrite. The addition of Ag2S selectively increased the copper dissolution from the chalcopyrite-containing ores in shake flasks with a recovery of 85.3% compared with 24.3% without Ag2S, while slightly decreased the iron yields from 51% to 41.8%. The copper extraction of the chalcoopyrite-containing waste rock in column leaching charged with 18 kg mass increased up to 21.7% in the presence of Ag2S, while only 3.4% in the absence of the catalyst. The mechanism of Ag2S catalysis could be explained well by the "Mixed potential model".

  4. Chalcopyrite leaching: The rate controlling factors

    Science.gov (United States)

    Li, J.; Kawashima, N.; Kaplun, K.; Absolon, V. J.; Gerson, A. R.

    2010-05-01

    The processes that determine the rate of chalcopyrite leaching are central to understanding how chalcopyrite (CuFeS 2) behaves under the environmentally adverse conditions of acid rock drainage. To this end the effect of the acid anion on chalcopyrite leach rates using a variety of acidic media (H 2SO 4, HClO 4, HCl and H 2SO 4 with 0.25 M NaCl) under carefully controlled solution conditions (pH 1 and 2, Eh 750 mV (SHE) and 75 °C) has been examined. These conditions have been chosen to enable sufficient leach rates for accurate experimental determination and to compare to the previous mechanistic analysis carried out by Harmer et al. (2006). Extensive surface analysis of leach residues demonstrated that variations in the surface speciation could not be responsible for the observed variations in leach rate. The rate of Cu release, however, was found to be first order with respect to Fe 3+ activity and inversely proportional with respect to H + activity to the power of 0.7: {1}/{S}{dC}/{dt}=(2.0±0.2){a}/{aH0.7} where S is the relative surface area, C is concentration of Cu in the solution (M), t is the time (h), 2.0 is the rate constant (M 0.7 h -1) and a and a are Fe 3+ and H + activities, respectively (M). The rate model was further validated against additional leaches carried out in H 2SO 4 media with the initial addition of Fe 3+ (8 mM as Fe 2(SO 4) 3) at 75 °C under various pH and Eh regimes. The only condition under which this rate model was found not to hold was at simultaneously low a and high a, that is at pH 1 and a<5×10-5M, where the concentration of dissolved O 2 may be leach rate determining.

  5. Bioleaching of chalcopyrite by mixed culture of moderately thermophilic microorganisms

    Institute of Scientific and Technical Information of China (English)

    WU Chang-bin; ZENG Wei-min; ZHOU Hong-bo; FU Bo; HUANG Ju-fang; QIU Guan-zhou; WANG Dian-zuo

    2007-01-01

    A mixed culture of moderately thermophilic microorganisms was enriched from acid mine drainages(AMDs) samples collected from several sulphide mines in China, and the bioleaching of chalcopyrite was conducted both in shake flask and bioreactor.The results show that in the shake flask, the mixture can tolerate 50 g/L chalcopyrite after being acclimated to gradually increased concentrations of chalcopyrite. The copper extraction increases obviously in bioleaching of chalcopyrite with moderately thermophilic microorganisms supplemented with 0.4 g/L yeast extract at 180 r/min, 74% copper can be extracted in the pulp of 50 g/L chalcopyrite after 20 d. Compared with copper extractions of mesophilic culture, unacclimated culture and acclimated culture without addition of yeast extract, that of accliniated culture with addition of yeast extract is increased by 53%, 44% and 16%,respectively. In a completely stirred tank reactor, the mass fraction of copper and total iron extraction reach up to 81% and 56%,respectively. The results also indicate that it is necessary to add a large amount of acid to the pulp to extract copper from chalcopyrite effectively.

  6. Mechanochemical leaching of chalcopyrite concentrate by sulfuric acid

    Science.gov (United States)

    Mohammadabad, Farhad Khorramshahi; Hejazi, Sina; khaki, Jalil Vahdati; Babakhani, Abolfazl

    2016-04-01

    This study aimed to introduce a new cost-effective methodology for increasing the leaching efficiency of chalcopyrite concentrates at ambient temperature and pressure. Mechanical activation was employed during the leaching (mechanochemical leaching) of chalcopyrite concentrates in a sulfuric acid medium at room temperature and atmospheric pressure. High energy ball milling process was used during the leaching to provide the mechanochemical leaching condition, and atomic absorption spectroscopy and cyclic voltammetry were used to determine the leaching behavior of chalcopyrite. Moreover, X-ray diffraction and scanning electron microscopy were used to characterize the chalcopyrite powder before and after leaching. The results demonstrated that mechanochemical leaching was effective; the extraction of copper increased significantly and continuously. Although the leaching efficiency of chalcopyrite was very low at ambient temperature, the percentages of copper dissolved in the presence of hydrogen peroxide (H2O2) and ferric sulfate (Fe2(SO4)3) after 20 h of mechanochemical leaching reached 28% and 33%, respectively. Given the efficiency of the developed method and the facts that it does not require the use of an autoclave and can be conducted at room temperature and atmospheric pressure, it represents an economical and easy-to-use method for the leaching industry.

  7. Leaching of Bornite Produced from the Sulfurization of Chalcopyrite

    Science.gov (United States)

    Veloso, T. C.; Paiva, P. R. P.; Silva, C. A.; Leão, V. A.

    2016-06-01

    The pyrometallurgical route accounts for 80 pct of world metallic copper production, because chalcopyrite, the most abundant copper sulfide, is refractory to hydrometallurgical treatment. However, pyrometallurgical routes are quite restrictive as far as copper concentrates are concerned mainly owing to limits on the concentration of impurities, such as fluorine, chlorine, and arsenic that can be tolerated. Such concentrates require innovative processing solutions because their market value is greatly reduced. A potential alternative is the transformation of chalcopyrite to a sulfide amenable to leaching, such as chalcocite, covellite, or bornite, through treatment in either aqueous or gaseous environments. In this study, the sulfurization of a chalcopyrite concentrate containing 78 pct CuFeS2 in the presence of gaseous sulfur was investigated, with the goal of demonstrating its conversion to the leachable phases, i.e., bornite and covellite. The concentrate was reacted with elemental sulfur in a tubular furnace at temperatures ranging from 573 K to 723 K (300 °C to 450 °C), followed by atmospheric leaching in an Fe(III)-bearing solution. The mineral phases in the sample were quantified using the Rietveld method, and it was shown that at temperatures below 673 K (400 °C) chalcopyrite was converted to covellite (41 pct) and pyrite (34 pct), whereas at temperatures above these, the reaction products were bornite (45 pct) and pyrite (31 pct). Leaching tests [6 hours at 353 K (80 °C)] showed significantly higher copper extraction rates after sulfurization (90 pct) than those using the raw chalcopyrite concentrate (15 pct).

  8. Kesterites and Chalcopyrites: A Comparison of Close Cousins; Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Repins, I.; Vora, N.; Beall, C.; Wei, S. H.; Yan, Y.; Romero, M.; Teeter, G.; Du, H.; To, B.; Young, M.; Noufi, R.

    2011-05-01

    Chalcopyrite solar cells based on CuInSe2 and associated alloys have demonstrated high efficiencies, with current annual shipments in the hundreds of megawatts (MW) range and increasing. Largely due to concern over possible indium (In) scarcity, a related set of materials, the kesterites, which comprise Cu2ZnSnS4 and associated alloys, has received increasing attention. Similarities and differences between kesterites and chalcopyrites are discussed as drawn from theory, depositions, and materials characterization. In particular, we discuss predictions from density functional theory, results from vacuum co-evaporation, and characterization via x-ray diffraction, scanning electron microscopy, electron beam-induced current, quantum efficiency, secondary ion mass spectroscopy, and luminescence.

  9. Bioleaching of chalcopyrite by pure and mixed culture

    Institute of Scientific and Technical Information of China (English)

    ZHANG Yan-sheng; QIN Wen-qing; WANG Jun; ZHEN Shi-jie; YANG Cong-ren; ZHANG Jian-wen; NAI Shao-shi; QIU Guan-zhou

    2008-01-01

    The bioleaching of chalcopyrite in shake flasks was investigated by using pure Acidithiobacillus ferrooxidans and mixed culture isolated from the acid mine drainage in Yushui and Dabaoshan Copper Mine in China,marked as YS and DB,respectively.The mixed culture consisted mainly of Acidithiobacillus ferrooxidans,Acidithiobacillus thiooxidans,and Leptospirillum spp.(Leptospirillum ferriphilum and Leptospirillum ferrooxians).The results show that the mixed culture is more efficient than the pure Acidithiobacillus ferrooxidans because of the presence of the sulfur-oxidizing cultures that positively increase the dissolution rate and the recovery of copper from chalcopyrite.The pH value decreases with the decrease of chalcopyrite leaching rate,because of the formation of jarosite as a passivation layer on the mineral surface during bioleaching.In the bioleaching using the mixed culture,low pH is got from the sulfur oxidizing inhibiting,the formation of jarosite.The copper extraction reaches 46.27% in mixed culture and 30.37% in pure Acidithiobacillus ferrooxidans after leaching for 75 d.

  10. Structural, optical, electron paramagnetic, thermal and dielectric characterization of chalcopyrite.

    Science.gov (United States)

    Prameena, B; Anbalagan, G; Gunasekaran, S; Ramkumaar, G R; Gowtham, B

    2014-03-25

    Chalcopyrite (CuFeS2) a variety of pyrite minerals was investigated through spectroscopic techniques and thermal analysis. The morphology and elemental analysis of the chalcopyrite have been done by high resolution SEM with EDAX. The lattice parameters were from the powder diffraction data (a=5.3003±0.0089 Å, c=10.3679±0.0289 Å; the volume of the unit cell=291.266 Å(3) with space group I42d (122)). The thermal decomposition behavior of chalcopyrite was studied by means of thermogravimetric analysis at three different heating rates 10, 15 and 20 °C/min. The values of effective activation energy (Ea), pre-exponential factor (ln A) for thermal decomposition have been measured at three different heating rates by employing Kissinger, Kim-Park and Flynn-Wall methods. Dielectric studies at different temperatures have also been carried out and it was found that both dielectric constant and dielectric loss decreases with the increase of frequency.

  11. Influence of chalcopyrite structure on their leaching by sodium nitrate in sulphuric acid

    Directory of Open Access Journals (Sweden)

    Miroslav Sokić

    2014-03-01

    Full Text Available During the chalcopyrite leaching by sodium nitrate and sulfuric acid solution, leaching rate decreases with increasing the time and a part of chalcopyrite mineral grains remains in the leach residue. In chalcopyrite concentrate, 95.5 % of chalcopyrite mineral occurs as in liberated grains, and the rest is in association with gangue minerals, which is very favorably from the aspect of hydrometallurgical treatment. Complex forms, like impregnations and complex intergrowths, do not exist. After experiments carried out, leaching of copper achieved 84 % at temperature 80 o C and time 240 min. In the all leach residues, 97 % chalcopyrite mineral grains occur as liberated with highly corroded surfaces. Therefore, the structural assembly of chalcopyrite grains is favorable and no reason to reduce the leaching rate in the final stage of reaction. Reason for this is elemental sulfur, which was formed during the reaction, precipitated at the particle surfaces, and slowed down the leaching rate in the final stage of leaching process.

  12. Kinetic process of oxidative leaching of chalcopyrite under low oxygen pressure and low temperature

    Institute of Scientific and Technical Information of China (English)

    QIU Ting-sheng; NIE Guang-hua; WANG Jun-feng; CUI Li-feng

    2007-01-01

    Kinetic process of oxidative leaching of chalcopyrite in chloride acid hydroxide medium under oxygen pressure and low temperature was investigated. The effect on leaching rate of chalcopyrite caused by these factors such as ore granularity, vitriol concentration, sodium chloride concentration, oxygen pressure and temperature was discussed. The results show that the leaching rate of chalcopyrite increases with decreasing the ore granularity. At the early stage of oxidative reaction, the copper leaching rate increases with increasing the oxygen pressure and dosage of vitriol concentration, while oxygen pressure affects leaching less at the later stage. At low temperature, the earlier oxidative leaching process of chalcopyrite is controlled by chemical reactions while the later one by diffusion. The chalcopyrite oxidative leaching rate has close relation with ion concentration in the leaching solution. The higher ion concentration is propitious for chalcopyrite leaching.

  13. The dissolution of chalcopyrite in chloride media; Lixiviacion de la calcopirita en medios clorurados

    Energy Technology Data Exchange (ETDEWEB)

    Ibanez, T.; Velasquez, L.

    2013-06-01

    The aim of this investigation is to determinate the effects of parameters and additives on the kinetics of dissolution of chalcopyrite on moderated conditions by means of dissolutions test with chalcopyrite concentrate and pure chalcopyrite in shake flasks and instrumented stirred reactors. A study of the dissolution of chalcopyrite in chloride solutions has demonstrated that the rate of dissolution of chalcopyrite is strongly dependent on the potential of the solution within a range of 540 to 630 mV (versus SHE). Leaching at pH around 2.5 results in increased rates of copper dissolution suggesting the possibility to keep the solution potential within the range. Both pyrite and silver ions enhance the dissolution of chalcopyrite and this effect increases when both species are present. The MnO{sub 2} has a negative effect on the dissolution increasing the solution potential to values where the rate decreases considerably. (Author)

  14. STUDY ON BIOLEACHING OF PRIMARY CHALCOPYRITE ORE WITH THERMOACIDOPHLIC ARCHAE

    Institute of Scientific and Technical Information of China (English)

    P. Zou; W.B. Zhang; T. Lei; J.K. Wang

    2006-01-01

    A high temperature-tolerating thermoacidophilic archae (TA) was isolated from water samples collected from a hot sulfur-containing spring in the Yunnan Province, China, and was used in bioleaching experiments of a low-grade chalcopyrite ore. The TA grow at temperatures ranging from 40 to 80℃, with 65℃ being the optimum temperature, and at pH values of 1.5 to 4.0, with an optimum pH value of 2.0. The bioleaching experiments of the chalcopyrite ore were conducted in both laboratory batch bioreactors and leaching columns. The results obtained from the bioreactor experiments showed that the TA bioleaching rate of copper reached 97% for a 12-day leaching period, while the bioleaching rate was 32.43% for thiobacillus ferrooxidans (Tf) leaching for the same leaching time. In the case of column leaching, tests of a two-phase leaching (196 days), that is,a two-month (56 days) Tf leaching in the first phase, followed by a 140-day TA leaching in the second phase were performed. The average leaching rate of copper achieved for the 140-day TA leaching was 195mg/(L· d), while for the control experiments, it was as low as 78mg/(L· d) for the Tf leaching, indicating that the TA possesses a more powerful oxidizing ability to the chalcopyrite than Tf. Therefore, it is suggested that the two-phase leaching process be applied to for the heap leaching operations, whereas, the TA can be used in the second phase when the temperature inside the heap has increased, and the primary copper sulfide minerals have already been partially oxidized with Tf beforehand in the first phase.

  15. Bio-oxidation of pyrite, chalcopyrite and pyrrhotite by Acidithiobacillus ferrooxidans

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    This paper deals with the bio-oxidation processes by Acidithiobacillus ferrooxidans of pyrite, chalcopyrite and pyrrhotite. Our experimental results show distinctive bio-oxidation characteristics for the three sulfide minerals. In the presence of A. ferrooxidans, the sulfide oxidation rates generally decrease in the order of pyrrhotite, chalcopyrite and pyrite. The pH during bio-oxidation of pyrite tends to decrease as a whole, whereas a rise-fall pattern was recorded for both chalcopyrite and pyrrhotite in their pH variations. No deposition was observed during the bio-oxidation of pyrite, suggesting a possible link to lower pH value in the process. However, large amounts of jarosite and element sulfur were determined in the bio-oxidation processes of chalcopyrite and pyrrhotite. A. ferrooxidans individuals were found directly as attachments to erosion pits on the smooth surface of pyrite. The erosion pits are similar to the bacterium in shape and length, and thus are probably products of dissolution of organic acid secreted by the cells on the mineral surface. More complicatedly, biofilm exists on the surfaces of chalcopyrite and pyrrhotite. This type of structured community of A. ferrooxidans is enclosed in the extracellular polymeric substances (EPS), and covered with the deposition generated in the bio-oxidation processes of chalcopyrite and pyrrhotite. Different bio-oxidation processes of pyrite, chalcopyrite and pyrrhotite may be linked mainly to characteristics of individual minerals and the pH in the reaction solution of the bio-oxidation system.

  16. Review on light management by nanostructures in chalcopyrite solar cells

    Science.gov (United States)

    Schmid, M.

    2017-04-01

    Light management has gained wide interest for various types of solar cells. This paper reviews the application of nanostructures for light management to chalcopyrite (CIGSe) type solar cells. Firstly, the relevance of light management for CIGSe solar cells will be introduced and concepts of nanostructures for absorption enhancement discussed. The development of ultra-thin CIGSe solar cells and examples for nanoparticle fabrication techniques together with their chances and challenges for application to CIGSe will be presented. Particular attention will be paid to nanostructures that have been applied to CIGSe solar cells, revealing many theoretical and some experimental results. Metallic and dielectric nanostructures as well as intrinsic nanotextures will be covered. For the future, combined considerations of optical and electrical properties will gain in importance.

  17. Visible scintillation photodetector device incorporating chalcopyrite semiconductor crystals

    Energy Technology Data Exchange (ETDEWEB)

    Stowe, Ashley C.; Burger, Arnold

    2017-04-04

    A photodetector device, including: a scintillator material operable for receiving incident radiation and emitting photons in response; a photodetector material coupled to the scintillator material operable for receiving the photons emitted by the scintillator material and generating a current in response, wherein the photodetector material includes a chalcopyrite semiconductor crystal; and a circuit coupled to the photodetector material operable for characterizing the incident radiation based on the current generated by the photodetector material. Optionally, the scintillator material includes a gamma scintillator material and the incident radiation received includes gamma rays. Optionally, the photodetector material is further operable for receiving thermal neutrons and generating a current in response. The circuit is further operable for characterizing the thermal neutrons based on the current generated by the photodetector material.

  18. Optimization of the use of carbon paste electrodes (CPE for electrochemical study of the chalcopyrite

    Directory of Open Access Journals (Sweden)

    Daniela G. Horta

    2009-01-01

    Full Text Available The use of carbon paste electrodes (CPE of mineral sulfides can be useful for electrochemical studies to overcome problems by using massive ones. Using CPE-chalcopyrite some variables were electrochemically evaluated. These variables were: (i the atmosphere of preparation (air or argon of CPE and elapsed time till its use; (ii scan rate for voltammetric measurements and (iii chalcopyrite concentration in the CPE. Based on cyclic voltammetry, open-circuit potential and electrochemical impedance results the recommendations are: oxygen-free atmosphere to prepare and kept the CPE until around two ours, scan rates from 10 to 40 mV s-1, and chalcopyrite concentrations > 20%.

  19. Bioleaching of chalcopyrite and bornite by moderately thermophilic bacteria:an emphasis on their interactions

    Institute of Scientific and Technical Information of China (English)

    Hong-bo Zhao; Jun Wang; Xiao-wen Gan; Wen-qing Qin; Ming-hao Hu; Guan-zhou Qiu

    2015-01-01

    Interactions between chalcopyrite and bornite during bioleaching by moderately thermophilic bacteria were investigated mainly by X-ray diffraction, scanning electron microscopy, and electrochemical measurements performed in conjunction with bioleaching experiments. The results showed that a synergistic effect existed between chalcopyrite and bornite during bioleaching by bothAcidithiobacillus caldus and Leptospirillum ferriphilum and that extremely high copper extraction could be achieved when chalcopyrite and bornite coexisted in a bioleaching system. Bornite dissolved preferentially because of its lower corrosion potential, and its dissolution was accelerated by the gal-vanic current during the initial stage of bioleaching. The galvanic current and optimum redox potential of 390−480 mV vs. Ag/AgCl pro-moted the reduction of chalcopyrite to chalcocite (Cu2S), thus accelerating its dissolution.

  20. Stepwise dissolution of chalcopyrite bioleaching by thermophileA.manzaensis and mesophileL. ferriphilum

    Institute of Scientific and Technical Information of China (English)

    顾帼华; 熊先学; 胡可婷; 李双棵; 王重庆

    2015-01-01

    Chalcopyrite dissolution was evaluated by bioleaching and electrochemical experiments with thermophileA. manzaensis (Acidianus manzaensis) and mesophileL. ferriphilum (Leptospirillum ferriphium) cultures at 65 °C and 40 °C, respectively. It was investigated that the bioleaching of chalcopyrite was stepwise. It was reduced to Cu2S at a lower redox potential locating in the whole bioleaching process byA. manzaensisat high temperature while only at initial days of bioleaching byL. ferriphilum at a relative low temperature. No reduced product was detected when the redox potential was beyond a high level (e.g., 550 mV (vs SCE)) bioleached byL. ferriphilum. Chalcopyrite bioleaching efficiency was substantially improved bioleached byA. manaensis compared to that byL. ferriphilum, which was mainly attributed to the reduction reaction occurring during bioleaching. The reductive intermediate Cu2S was more amenable to oxidation than chalcopyrite, causing enhanced copper extraction.

  1. Chalcopyrite CuGaTe{sub 2}: a high-efficiency bulk thermoelectric material

    Energy Technology Data Exchange (ETDEWEB)

    Plirdpring, Theerayuth; Harnwunggmoung, Adul [Graduate School of Engineering, Osaka University, Suita (Japan); Thermoelectric and Nanotechnology Research Center, Faculty of Science and Technology, Rajamangala University of Technology Suvarnabhumi, Huntra Phranakhon Si Ayutthaya (Thailand); Kurosaki, Ken; Sugahara, Tohru; Ohishi, Yuji; Muta, Hiroaki [Graduate School of Engineering, Osaka University, Suita (Japan); Kosuga, Atsuko [Nanoscience and Nanotechnology Research Center, Research Organization for the 21st Century, Osaka Prefecture University, Osaka (Japan); Day, Tristan; Snyder, G. Jeffrey [Department of Materials Science, California Institute of Technology, Pasadena, CA (United States); Firdosy, Samad [Jet Propulsion Laboratory, Pasadena, CA (United States); Ravi, Vilupanur [Jet Propulsion Laboratory, Pasadena, CA (United States); California State Polytechnic University, Pomona, CA (United States); Yamanaka, Shinsuke [Graduate School of Engineering, Osaka University, Suita (Japan); Research Institute of Nuclear Engineering, University of Fukui (Japan)

    2012-07-17

    CuGaTe{sub 2} with a chalcopyrite structure demonstrates promising thermoelectric properties. The maximum figure of merit ZT is 1.4 at 950 K. CuGaTe{sub 2} and related chalcopyrites are a new class of high-efficiency bulk thermoelectric material for high-temperature applications. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  2. Dual effects of sodium sulfide on the flotation behavior of chalcopyrite:I. Effect of pulp potential

    Institute of Scientific and Technical Information of China (English)

    Bijan Taheri; Mahmoud Abdollahy; Sied Ziaedin Shafaei Tonkaboni; Soheyla Javadian; Mohammadreza Yarahmadi

    2014-01-01

    This study explores the flotation behavior of chalcopyrite in the presence of different concentrations of sodium sulfide (Na2S·9H2O) at pH 12 under controlled potential conditions. It was observed that the flotation of chalcopyrite is not depressed completely when the pulp potential is low, even at high concentrations of sodium sulfide, i.e., 10-1-10-2 mol/L. However, a partial and controlled oxida-tion of pulp does enhance the effectiveness of sodium sulfide on the depression of chalcopyrite. Characterization of the chalcopyrite particle surface by X-ray photoelectron spectroscopy allowed the identification of hydrophilic and hydrophobic surface species, which are responsi-ble for the depression and flotation of chalcopyrite. Changes in pulp potential were found to be an effective float controlling parameter, by which Na2S can be used to initiate or depress the flotation behavior of chalcopyrite.

  3. Electrochemical behavior of chalcopyrite in presence of Thiobacillus ferrooxidans

    Institute of Scientific and Technical Information of China (English)

    LI Hong-xu; QIU Guan-zhou; HU Yue-hua; CANG Da-qiang; WANG Dian-zuo

    2006-01-01

    The chalcopyrite anode dissolution behavior in the presence or absence of bacteria in 9 K media using bacteria modified powder microelectrode at 30 ℃ was studied. It is found that during the anode dissolution, many intermediate transient reactions occur accompanying with the production of chalcocite and covellite at potential between -0.075 V and -0.025 V (vs SCE). At low scanning potential between -0.1 and -0.250 V, the iron ion is released in ferrous form, but at the relative high potential up to 0.7 V, it is the ferric one. The presence of Thiobacillus ferrooxidans makes peak current increase and the initial peak potential negatively move, hinting the decomposed oxidation reaction easily occurred and especially the iron ion released and ferrous oxidation reaction enhanced. The characteristic at potential between -0.75 and -0.5 V demonstrates the Thiobacillus ferrooxidans also contributes to the element sulfur formed on the oxidation surface and removed during anode process. The added ferric in the cell could enhance the dissolution reaction, while the increased acid under pH=2 might slightly hamper the process. The anode dissolution kinetics studies show that the presence of bacteria could decease corrosion potential from 0.238 V to 0.184 V and increase the corrosion current density from 1.632 14×10-8 A/cm2 to 2.374 11×10-7A/cm2.

  4. Tunable band structure and effective mass of disordered chalcopyrite

    Science.gov (United States)

    Wang, Ze-Lian; Xie, Wen-Hui; Zhao, Yong-Hong

    2017-02-01

    The band structure and effective mass of disordered chalcopyrite photovoltaic materials Cu1- x Ag x Ga X 2 ( X = S, Se) are investigated by density functional theory. Special quasirandom structures are used to mimic local atomic disorders at Cu/Ag sites. A local density plus correction method is adopted to obtain correct semiconductor band gaps for all compounds. The bandgap anomaly can be seen for both sulfides and selenides, where the gap values of Ag compounds are larger than those of Cu compounds. Band gaps can be modulated from 1.63 to 1.78 eV for Cu1- x Ag x Ga Se 2, and from 2.33 to 2.64 eV for Cu1- x Ag x Ga S 2. The band gap minima and maxima occur at around x = 0:5 and x = 1, respectively, for both sulfides and selenides. In order to show the transport properties of Cu1- x Ag x Ga X 2, the effective mass is shown as a function of disordered Ag concentration. Finally, detailed band structures are shown to clarify the phonon momentum needed by the fundamental indirect-gap transitions. These results should be helpful in designing high-efficiency photovoltaic devices, with both better absorption and high mobility, by Ag-doping in CuGa X 2.

  5. Influence of the surface speciation on biofilm attachment to chalcopyrite by Acidithiobacillus thiooxidans.

    Science.gov (United States)

    Lara, René H; García-Meza, J Viridiana; González, Ignacio; Cruz, Roel

    2013-03-01

    Surfaces of massive chalcopyrite (CuFeS2) electrodes were modified by applying variable oxidation potential pulses under growth media in order to induce the formation of different secondary phases (e.g., copper-rich polysulfides, S n(2-); elemental sulfur, S(0); and covellite, CuS). The evolution of reactivity (oxidation capacity) of the resulting chalcopyrite surfaces considers a transition from passive or inactive (containing CuS and S n(2-)) to active (containing increasing amounts of S(0)) phases. Modified surfaces were incubated with cells of sulfur-oxidizing bacteria (Acidithiobacillus thiooxidans) for 24 h in a specific culture medium (pH 2). Abiotic control experiments were also performed to compare chemical and biological oxidation. After incubation, the density of cells attached to chalcopyrite surfaces, the structure of the formed biofilm, and their exopolysaccharides and nucleic acids were analyzed by confocal laser scanning microscopy (CLSM) and scanning electron microscopy coupled to dispersive X-ray analysis (SEM-EDS). Additionally, CuS and S n(2-)/S(0) speciation, as well as secondary phase evolution, was carried out on biooxidized and abiotic chalcopyrite surfaces using Raman spectroscopy and SEM-EDS. Our results indicate that oxidized chalcopyrite surfaces initially containing inactive S n(2-) and S n(2-)/CuS phases were less colonized by A. thiooxidans as compared with surfaces containing active phases (mainly S(0)). Furthermore, it was observed that cells were partially covered by CuS and S(0) phases during biooxidation, especially at highly oxidized chalcopyrite surfaces, suggesting the innocuous effect of CuS phases during A. thiooxidans performance. These results may contribute to understanding the effect of the concomitant formation of refractory secondary phases (as CuS and inactive S n(2-)) during the biooxidation of chalcopyrite by sulfur-oxidizing microorganisms in bioleaching systems.

  6. Chalcopyrite semimagnetic semiconductors: From nanocomposite to homogeneous material

    Directory of Open Access Journals (Sweden)

    Kilanski L.

    2014-01-01

    Full Text Available Currently, complex ferromagnetic semiconductor systems are of significant interest due to their potential applicability in spintronics. A key feature in order to use semiconductor materials in spintronics is the presence of room temperature ferromagnetism. This feature was recently observed and is intensively studied in several Mn-alloyed II-IV-V2 group diluted magnetic semiconductor systems. The paper reviews the origin of room temperature ferromagnetism in II-IV-V2 compounds. In view of our recent reports the room temperature ferromagnetism in Mn-alloyed chalcopyrite semiconductors with more than 5 molar % of Mn is due to the presence of MnAs clusters. The solubility of magnetic impurities in bulk II-IV-V2 materials is of the order of a few percent, depending on the alloy composition. High values of the conducting hole - Mn ion exchange constant Jpd have significant value equal to 0.75 eV for Zn0.997Mn0.003GeAs2. The sample quality has significant effect on the magnetotransport of the alloy. The magnetoresistance of the alloy change main physical mechanism from spin-disorder scattering and weak localization for homogeneous samples to cluster-related geometrical effect observed for nanocomposite samples. The magnetoresistance of the II-IV-V2 alloys can be then tuned up to a few hundreds of percent via changes of the chemical composition of the alloy as well as a degree of disorder present in a material. [Projekat Ministarstva nauke Republike Srbije, br. III45003

  7. Chalcopyrite Thin Film Materials for Photoelectrochemical Hydrogen Evolution from Water under Sunlight

    Directory of Open Access Journals (Sweden)

    Hiroyuki Kaneko

    2015-07-01

    Full Text Available Copper chalcopyrite is a promising candidate for a photocathode material for photoelectrochemical (PEC water splitting because of its high half-cell solar-to-hydrogen conversion efficiency (HC-STH, relatively simple and low-cost preparation process, and chemical stability. This paper reviews recent advances in copper chalcopyrite photocathodes. The PEC properties of copper chalcopyrite photocathodes have improved fairly rapidly: HC-STH values of 0.25% and 8.5% in 2012 and 2015, respectively. On the other hand, the onset potential remains insufficient, owing to the shallow valence band maximum mainly consisting of Cu 3d orbitals. In order to improve the onset potential, we explored substituting Cu for Ag and investigate the PEC properties of silver gallium selenide (AGSe thin film photocathodes for varying compositions, film growth atmospheres, and surfaces. The modified AGSe photocathodes showed a higher onset potential than copper chalcopyrite photocathodes. It was demonstrated that element substitution of copper chalcopyrite can help to achieve more efficient PEC water splitting.

  8. Galvanic Interaction between Chalcopyrite and Pyrite with Low Alloy and High Carbon Chromium Steel Ball

    Directory of Open Access Journals (Sweden)

    Asghar Azizi

    2013-01-01

    Full Text Available This study was aimed to investigate the galvanic interaction between pyrite and chalcopyrite with two types of grinding media (low alloy and high carbon chromium steel ball in grinding of a porphyry copper sulphide ore. Results indicated that injection of different gases into mill altered the oxidation-reduction environment during grinding. High carbon chromium steel ball under nitrogen gas has the lowest galvanic current, and low alloy steel ball under oxygen gas had the highest galvanic current. Also, results showed that the media is anodic relative to pyrite and chalcopyrite, and therefore pyrite or chalcopyrite with a higher rest potential acted as the cathode, whilst the grinding media with a lower rest potential acted as the anode, when they are electrochemically contacted. It was also found that low alloy steel under oxygen produced the highest amount of EDTA extractable iron in the slurry, whilst high carbon chromium steel under nitrogen atmosphere led to the lowest amount.

  9. Structural, microstructural, and thermal characterizations of a chalcopyrite concentrate from the Singhbhum shear zone, India

    Institute of Scientific and Technical Information of China (English)

    Ritayan Chatterjee; Shamik Chaudhuri; Saikat Kumar Kuila; Dinabandhu Ghosh

    2015-01-01

    The structural and morphological characterizations of a chalcopyrite concentrate, collected from the Indian Copper Complex, Ghatshila, India, were carried out by X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The con-centrate powder was composed mainly of free chalcopyrite and low quartz in about 3:1 weight ratio. The particle size was about 100 µm. Spectroscopic studies (FTIR, Raman, UV-visible) of the concentrate supported the XRD findings, and also revealed a marginal oxidation of the sulfide phase. The energy band gap of the sulfide was found to be 3.4 eV. Differential thermal analysis and thermogravimetry of the con-centrate showed a decomposition of chalcopyrite at 658 K with an activation energy of 208 kJ⋅mol−1, and two successive structural changes of silica at 848 K and 1145 K.

  10. Structural characteristics of chalcopyrite from a Cu(Au) ore deposit in the Carajas Mineral Province, Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Aparecida Ribeiro, Andreza; Quintao Lima, Diana; Anderson Duarte, Helio; Murad, Enver [ICEx, UFMG, Departamento de Quimica (Brazil); Pereira, Marcio Cesar, E-mail: mcpqui@yahoo.com.br [Universidade Federal dos Vales do Jequitinhonha e Mucuri, Instituto de Ciencia e Tecnologia (Brazil); Tadeu de Freitas Suita, Marcos [UFOP, Departamento de Geologia (Brazil); Ardisson, Jose Domingos [Centro de Desenvolvimento da Tecnologia Nuclear (Brazil); Fabris, Jose Domingos [Universidade Federal dos Vales do Jequitinhonha e Mucuri, UFVJM (Brazil)

    2011-11-15

    Moessbauer spectra and X-ray diffraction data show a chalcopyrite from the Cristalino Cu(Au) deposit in the Carajas Mineral Province in northern Brazil to consist of a single, tetragonal phase. This is in stark contrast to a previously described chalcopyrite from the Camaqua copper mine in southern Brazil, obviously reflecting differences in mineral (and thus ore deposit) genesis.

  11. The influence of mechanical activation of chalcopyrite on the selective leaching of copper by sulphuric acid

    Directory of Open Access Journals (Sweden)

    Achimovičová, M.

    2006-01-01

    Full Text Available In this paper chalcopyrite, CuFeS2, has been selective leached by H2SO4 as leaching agent (170 g/dm3 in procedure of hydrometallurgical production of copper. Mechanical activation of the chalcopyrite resulted in mechanochemical surface oxidation as well as in the mineral surface and bulk disordering. Furthermore, the formation of agglomerates during grinding was also occured. Surface changes of the samples using infrared spectroscopy and scanning electron microscopy methods were investigated before and after leaching. The leaching rate, specific surface area, structural disorder as well as copper extraction increased with the mechanical activation of mineral.

  12. Combined DFT and XPS investigation of iodine anions adsorption on the sulfur terminated (001) chalcopyrite surface

    Science.gov (United States)

    Li, Kui; Zhao, Yaolin; Zhang, Peng; He, Chaohui; Deng, Jia; Ding, Shujiang; Shi, Weiqun

    2016-12-01

    The adsorption of iodine anions (iodide and iodate) on the sulfur terminated (001) chalcopyrite surface has been systematically investigated combining first-principles calculations based on density functional theory (DFT) with X-ray photoelectron spectroscopy (XPS) measurements. Based on the total energy calculations and geometric optimization, the thermodynamically preferred site was copper atom for iodide adsorption and iron atom for iodate adsorption, respectively. In the case of Cu site mode, the iodate underwent a dissociative adsorption, where one Isbnd O bond of iodate ion was broken and the dissociative oxygen atom adsorbed on the adjacent sulphur site. Projected density of states (PDOS) analysis further clarified the interaction mechanism between active sites of chalcopyrite surface and adsorbates. In addition, full-range XPS spectra qualitatively revealed the presence of iodine on chalcopyrite surface. High resolution XPS spectra of the I 3d peaks after adsorption verified the chemical environment of iodine. The binding energies of 618.8 eV and 623.5 eV for I 3d5/2 peaks unveiled that the adsorption of iodide and iodate ions on copper-iron sulfide minerals was the result of formation of low solubility metal iodides precipitate. Also two I 3d peaks with low intensity around 618 eV and 630 eV might be related to the inorganic reduction of iodate to iodide by reducing S2- ion of chalcopyrite.

  13. Structural characteristics of chalcopyrite from a Cu(Au) ore deposit in the Carajás Mineral Province, Brazil

    Science.gov (United States)

    Ribeiro, Andreza Aparecida; Lima, Diana Quintão; Duarte, Hélio Anderson; Murad, Enver; Pereira, Márcio César; de Freitas Suita, Marcos Tadeu; Ardisson, José Domingos; Fabris, José Domingos

    2011-11-01

    Mössbauer spectra and X-ray diffraction data show a chalcopyrite from the Cristalino Cu(Au) deposit in the Carajás Mineral Province in northern Brazil to consist of a single, tetragonal phase. This is in stark contrast to a previously described chalcopyrite from the Camaquã copper mine in southern Brazil, obviously reflecting differences in mineral (and thus ore deposit) genesis.

  14. Biofilm forming and leaching mechanism during bioleaching chalcopyrite by Thiobacillus ferrooxidans

    Institute of Scientific and Technical Information of China (English)

    傅建华; 胡岳华; 邱冠周; 柳建设; 徐竞

    2004-01-01

    The mechanism of attachment and leaching of thiobacillus ferrooxcidans (T. f. ) on chalcopyrite were studied. The shaking flasks with bacteria were observed by SEM. The process of T. f attached to the surface of the mineral sample and the biofilm forming were described. The promoting role of the biofilm for bioleaching was discussed. The existence of Fe2+ in the exopolysaccharide layer of T. f was demonstrated by EM(electronic microscope)cell-chemistry analysis. These results show that under the proper growth condition of bacteria, bioleaching of chalcopyrite results in the formation of complete biofilm after 2 - 3 weeks. There are iron ions in the outer layer polymer of T. f. , which provides the micro-environment for themselves, and can guaruntee the energy needed for the bacteria growth in the biofilm. At the same time, Fe3+ ions produced oxidize sulfide which brings about the increase of both growth rate of the bacterial and leaching rate of sulfide minerals.

  15. Efficacy of chalcopyrite bioleaching using a pure and a mixed bacterium

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To determine the efficacy of chalcopyrite bioleaching using pure cultures of Thiobacillus ferrooxidans or Thiobacillus thiooxidans and a mixed culture composed of Thiobacillus ferrooxidans and Thiobacillus thiooxidans, experiments were carried out mixed culture composed of Thiobacillusferrooxidans and Thiobacillus thiooxidans is higher than that in a pure culture. On the other hand, an important potential of Thiobacillus thiooxidans to leaching chalcopyrite was indicated. Thiobacillus thiooxidans can prevent jarosites accumulating on the substrate and allow further copper to dissolute through the action of ferric ion. The selection of the suitable pH in a leaching solution would be significant. Thiobacillus thiooxidans and Thiobacillus ferrooxidans play an important role in the bioleaching process. Finally, the mechanism and the reason for iron precipitation were also discussed in detail.

  16. Adhesion forces between cells of Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans or Leptospirillum ferrooxidans and chalcopyrite.

    Science.gov (United States)

    Zhu, Jianyu; Li, Qian; Jiao, Weifeng; Jiang, Hao; Sand, Wolfgang; Xia, Jinlan; Liu, Xueduan; Qin, Wenqing; Qiu, Guanzhou; Hu, Yuehua; Chai, Liyuan

    2012-06-01

    The efficiency of copper leaching is improved by bacteria attached to chalcopyrite. Therefore, the study of the attachment mechanism to control leaching is important. The adhesion of three species of leaching microorganisms including Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans and Leptospirillum ferrooxidans to chalcopyrite was investigated by using atomic force microscopy (AFM). The forces were measured with tip-immobilized cells approached to and retracted from the mineral. The results show that both the surface charge and the hydrophobicity of bacteria cells influence the adhesion force. Furthermore, the adhesion force decreased in case the extracellular polymeric substances (EPS) had been removed. In addition, the data indicate that the amount of attached cells increased with increasing adhesion force.

  17. A study of energy gap, refractive index and electronic polarizability of ternary chalcopyrite semiconductors

    Directory of Open Access Journals (Sweden)

    A Ahmad

    2014-12-01

    Full Text Available A simple relation between the optical electronegativity, energy gap, refractive index and electronic polarizability is given for ternary chalcopyrite semiconductors. Energy gap has been evaluated from the optical electronegativity whereas refractive index and electronic polarizability values have been evaluated from the energy gap by proposing a linear relation between them. The calculated values are in fair agreement with the experimental values and earlier researchers. This work highlights the significance of interrelation between these parameters.

  18. Computational Study of Chalcopyrite Semiconductors and Their Non-Linear Optical Properties

    Science.gov (United States)

    2007-09-12

    SPONSOR/MONITOR’S ACRONYM Air Force Office of AFOSR Scientific Research Donald J. Silversmith 4015 Wilson Blvd Room 713 11. SPONSOR/MONITOR’S REPORT...34First-principles Calculations Based Desing of Chalcopyrite Semicon- ductors for Nonlinear Optical frequency Conversion," Walter R. L. Lambrecht...in ZnGeP 2 ," X. Jiang, M. S. Miao and W. R. L. Lambrecht, Research Showcase 2004, at Case Western Reserve University, April 2, 2004, 5. "Does the

  19. Passivation of chalcopyrite during the leaching with sulphuric acid solution in presence of sodium nitrate

    Directory of Open Access Journals (Sweden)

    Sokić Miroslav D.

    2010-01-01

    Full Text Available In this work, the process of the chalcopyrite leaching in sulphuric acid solution was investigated. Sodium nitrate was used as oxidant in the leaching process. Chemical reactions of leaching and their thermodynamic possibilities are predicted based on the calculated Gibbs energies and analysis of E−pH diagrams. The negative values of the Gibbs energy show that all chemical reactions are thermodynamically feasible at atmospheric pressure and in a temperature range 25-90°C. At high electrode potential and low pH values, Cu2+, Fe2+ and Fe3+ ions exist in water solutions. The increase of temperature reduces the probability of Fe3+ ion existence in the system. The chalcopyrite concentrate, enriched in the “Rudnik” flotation plant, with 27.08% Cu, 25.12% Fe, 4.15% Zn and 2.28% Pb was used in the work. XRD and DTA analysis of the concentrate reveals that the sample contains mainly the chalcopyrite with small amount of sphalerite. For the description of the reaction of leaching process the leach residuals, obtained at different conditions, were chosen for XRD, TG/DTA and SEM/EDX analyses. The elemental sulphur and chalcopyrite phases identified in leach residuals confirm our prediction that the elemental sulphur is formed during the leaching process. Accordingly, elemental sulphur is the main product of the reaction, while a minor amount of sulphide sulphur is oxidized to sulphate during the leaching. The sulphur formed during the reaction was precipitated at the particle surfaces, and slowed down the leaching rate in the final stage of leaching process. In the initial stage, the reaction rate was controlled by the surface reaction. The mechanism, latter has been changed into a diffusion controlled one.

  20. Diffusion in copper sulphides. An experimental study of chalcocite, chalcopyrite and bornite

    Energy Technology Data Exchange (ETDEWEB)

    Berger, R.; Bucur, R.V. [Uppsala Univ. (Sweden). Inst. of Chemistry

    1996-01-01

    Diffusion measurements on three copper-containing sulphides have been performed by an electrochemical potentiometric method. Chalcocite (Cu{sub 2}S), Chalcopyrite (CuFeS{sub 2}) and Bornite (Cu{sub 5}FeS{sub 4}) were synthesized and fully characterized by X-ray diffraction. The diffusivities were measured on compacted powders yielding both the chemical and the component diffusion coefficients in the temperature range 5-50 C. The chemical diffusion coefficients found were: for Chalcocite 38.7*exp (-5600/T), for Chalcopyrite 15.4*exp(-6000/T) and for Bornite 14.4*exp(-4900/T). The diffusion coefficient for Chalcocite is in good agreement with values found previously, and a reasonable agreement is also found for Chalcopyrite and Bornite when our data are compared with values acquired at much higher temperatures with a different technique. The activation energies (here on a Kelvin scale) are remarkably similar for the three sulfides, considering that their relative errors are of a 10% magnitude, which indicates that the bonding strengths and the diffusion mechanisms are similar. The chemical diffusion coefficients which enter the empirical Fick`s diffusion laws that describe concentration changes, are of the order of exp(-8) to exp (-7) cm{sup 2}/s at room temperature. Such values bring the ion mobilities near values found for solid state `fast ion conductors`, used as electrolytes at elevated temperatures. 17 refs, 8 figs, 5 tabs.

  1. Investigation of energy gene expressions and community structures of free and attached acidophilic bacteria in chalcopyrite bioleaching.

    Science.gov (United States)

    Zhu, Jianyu; Jiao, Weifeng; Li, Qian; Liu, Xueduan; Qin, Wenqing; Qiu, Guanzhou; Hu, Yuehua; Chai, Liyuan

    2012-12-01

    In order to better understand the bioleaching mechanism, expression of genes involved in energy conservation and community structure of free and attached acidophilic bacteria in chalcopyrite bioleaching were investigated. Using quantitative real-time PCR, we studied the expression of genes involved in energy conservation in free and attached Acidithiobacillus ferrooxidans during bioleaching of chalcopyrite. Sulfur oxidation genes of attached A. ferrooxidans were up-regulated while ferrous iron oxidation genes were down-regulated compared with free A. ferrooxidans in the solution. The up-regulation may be induced by elemental sulfur on the mineral surface. This conclusion was supported by the results of HPLC analysis. Sulfur-oxidizing Acidithiobacillus thiooxidans and ferrous-oxidizing Leptospirillum ferrooxidans were the members of the mixed culture in chalcopyrite bioleaching. Study of the community structure of free and attached bacteria showed that A. thiooxidans dominated the attached bacteria while L. ferrooxidans dominated the free bacteria. With respect to available energy sources during bioleaching of chalcopyrite, sulfur-oxidizers tend to be on the mineral surfaces whereas ferrous iron-oxidizers tend to be suspended in the aqueous phase. Taken together, these results indicate that the main role of attached acidophilic bacteria was to oxidize elemental sulfur and dissolution of chalcopyrite involved chiefly an indirect bioleaching mechanism.

  2. Sputtered Zn(O,S) for junction formation in chalcopyrite-based thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Grimm, A.; Just, J.; Kieven, D.; Lauermann, I.; Rissom, T.; Klenk, R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Palm, J. [AVANCIS GmbH and Co. KG, Munich (Germany); Neisser, A. [Sulfurcell Solartechnik GmbH, Berlin (Germany)

    2010-06-15

    In an effort to eliminate the standard CdS buffer layer from chalcopyrite-based thin film solar cells we have investigated sputtered Zn(O,S) films. They were prepared by partially reactive sputtering from a ZnS target in an argon/oxygen mixture. Single phase, polycrystalline films were achieved for substrate temperatures of at least 100 C. Test devices prepared in a completely dry process showed superior blue response and active area conversion efficiencies up to 13.7%. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  3. Magnetic exchange interactions in Mn doped ZnSnAs{sub 2} chalcopyrite

    Energy Technology Data Exchange (ETDEWEB)

    Bouhani-Benziane, H.; Sahnoun, O. [Laboratoire de Physique Quantique de la Matière et Modélisation Mathématique (LPQ3M), University of Mascara (Algeria); Sahnoun, M., E-mail: sahnoun_cum@yahoo.fr [Laboratoire de Physique Quantique de la Matière et Modélisation Mathématique (LPQ3M), University of Mascara (Algeria); Department of Chemistry, University of Fribourg (Switzerland); Driz, M. [Laboratoire de Sciences des Matériaux (LSM), University of Sidi Bel Abbes (Algeria); Daul, C. [Department of Chemistry, University of Fribourg (Switzerland)

    2015-12-15

    Accurate ab initio full-potential augmented plane wave (FP-LAPW) electronic calculations within generalized gradient approximation have been performed for Mn doped ZnSnAs{sub 2} chalcopyrites, focusing on their electronic and magnetic properties as a function of the geometry related to low Mn-impurity concentration and the spin magnetic alignment (i.e., ferromagnetic vs antiferromagnetic). As expected, Mn is found to be a source of holes and localized magnetic moments of about 4 µ{sub B} per Mn atom are calculated which are sufficiently large. The defect calculations are firstly performed by replacing a single cation (namely Zn and Sn) with a single Mn atom in the pure chalcopyrite ZnSnAs{sub 2} supercell, and their corresponding formation energies show that the substitution of a Sn atom (rather than Zn) by Mn is strongly favored. Thereafter, a comparison of total energy differences between ferromagnetic (FM) and antiferromagnetic (AFM) are given. Surprisingly, the exchange interaction between a Mn pairs is found to oscillate with the distance between them. Consequently, the AFM alignment is energetically favored in Mn-doped ZnSnAs{sub 2} compounds, except for low impurity concentration associated with lower distances between neighboring Mn impurities, in this case the stabilization of FM increases. Moreover, the ferromagnetic alignment in the Mn-doped ZnSnAs{sub 2} systems behaves half-metallic; the valence band for majority spin orientation is partially filled while there is a gap in the density of states for the minority spin orientation. This semiconducting gap of ~1 eV opened up in the minority channel and is due to the large bonding–antibonding splitting from the p–d hybridization. Our findings suggest that the Mn-doped ZnSnAs{sub 2} chalcopyrites could be a different class of ferromagnetic semiconductors. - Highlights: • ab initio calculations were performed on Mn doped ZnSnAs{sub 2} chalcopyrite. • Substitution of a Sn atom (rather than Zn) by Mn

  4. Insights to the effects of free cells on community structure of attached cells and chalcopyrite bioleaching during different stages.

    Science.gov (United States)

    Feng, Shoushuai; Yang, Hailin; Wang, Wu

    2016-01-01

    The effects of free cells on community structure of attached cells and chalcopyrite bioleaching by Acidithiobacillus sp. during different stages were investigated. The attached cells of Acidithiobacillus thiooxidans owned the community advantage from 14thd to the end of bioprocess in the normal system. The community structure of attached cells was greatly influenced in the free cells-deficient systems. Compared to A. thiooxidans, the attached cells community of Acidithiobacillus ferrooxidans had a higher dependence on its free cells. Meanwhile, the analysis of key biochemical parameters revealed that the effects of free cells on chalcopyrite bioleaching in different stages were diverse, ranging from 32.8% to 64.3%. The bioleaching contribution of free cells of A. ferrooxidans in the stationary stage (8-14thd) was higher than those of A. thiooxidans, while the situation was gradually reversed in the jarosite passivation inhibited stage (26-40thd). These results may be useful in guiding chalcopyrite bioleaching.

  5. Ab-initio vibrational properties of transition metal chalcopyrite alloys determined as high-efficiency intermediate-band photovoltaic materials

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, P. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM. Ciudad Universitaria s/n, 28040 Madrid (Spain); Instituto de Catalisis y Petroleoquimica, CSIC. Marie Curie 2, Cantoblanco, 28049 Madrid (Spain)], E-mail: pablop@etsit.upm.es; Aguilera, I.; Wahnon, P. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM. Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2008-08-30

    In this work, we present frozen phonon and linear response ab-initio research into the vibrational properties of the CuGaS{sub 2} chalcopyrite and transition metal substituted (CuGaS{sub 2})M alloys. These systems are potential candidates for developing a novel solar-cell material with enhanced optoelectronic properties based in the implementation of the intermediate-band concept. We have previously carried out ab-initio calculations of the electronic properties of these kinds of chalcopyrite metal alloys showing a narrow transition metal band isolated in the semiconductor band gap. The substitutes used in the present work are the 3d metal elements, Titanium and Chromium. For the theoretical calculations we use standard density functional theory at local density and generalized gradient approximation levels. We found that the optical phonon branches of the transition metal chalcopyrite, are very sensitive to the specific bonding geometry and small changes in the transition metal environment.

  6. Structural and Thermoelectronic Properties of Chalcopyrite MgSiX2 (X = P, As, Sb)

    Science.gov (United States)

    Kocak, B.; Ciftci, Y. O.; Surucu, G.

    2017-01-01

    We have explored the structural, electronic, optical, and mechanical properties of the magnesium-based chalcopyrites MgSiP2, MgSiAs2, and MgSiSb2 using density functional theory with five different generalized gradient approximation (GGA) functionals: Perdew-Wang (1991), Perdew-Burke-Ernzerhof, revised Perdew-Burke-Ernzerhof, modified Perdew-Burke-Ernzerhof for solids, and Armiento-Mattson (2005) as well as the local density approximation. Change of the constituent element from P to Sb significantly affected the lattice constants, elastic constants, and thermal and dielectric properties. Our theoretically computed results are in reasonable agreement with experiments and other theoretical calculations. The electronic band structure results imply that all three considered compounds are semiconductors. MgSiP2 has the highest value of elastic constants, and bulk and shear moduli compared with the other two binary chalcopyrites. Furthermore, the optical response in terms of the dielectric functions, optical reflectivity, refractive index, extinction coefficient, and electron energy loss of the compounds were also investigated in the energy range from 0 eV to 15 eV. The calculated optical results reveal optical polarization anisotropy for all three compounds, making them useful for optoelectronic device applications. Moreover, specific focus is also given to quantify the dependence of various thermal properties on finite pressure/temperature within the quasiharmonic approximation.

  7. Modelling of chalcopyrite oxidation reactions in the Outokumpu flash smelting process

    Energy Technology Data Exchange (ETDEWEB)

    Ahokainen, T.; Jokilaakso, A. [Helsinki Univ. of Technology, Otaniemi (Finland)

    1996-12-31

    A mathematical model for simulating oxidation reactions of chalcopyrite particles together with momentum, heat and mass transfer between particle and gas phase in a flash smelting furnace reaction shaft is presented. In simulation, the equations governing the gas flow are solved numerically with a commercial fluid flow package, Phoenics. The particle phase is introduced into the gas flow by a Particle Source In Cell (PSIC) - technique, where a number of discrete particles is tracked in a gas flow and the relevant source terms for momentum, mass, and heat transfer are added to the gas phase equations. The gas phase equations used are elliptic in nature and the fluid turbulence is described by the (k-{epsilon}) -model. Thermal gas phase radiation is simulated with a six-flux radiation model. The chemical reactions of concentrate particles are assumed to happen at two sharp interfaces, and a shrinking core model is applied to describe the mass transfer of chemical species through the reaction product layer. In a molten state, the oxygen consumption is controlled by a film penetration concept. The reacting concentrate particles are a mixture of chalcopyrite and silica. Also a certain amount of pure inert silica is fed to the process as flux. In the simulations the calculation domain includes the concentrate burner and a cylindrical reaction shaft of an industrial scale flash smelting furnace. Some examples about the simulations carried out by the combustion model are presented. (author)

  8. Structural and Thermoelectronic Properties of Chalcopyrite MgSiX2 (X = P, As, Sb)

    Science.gov (United States)

    Kocak, B.; Ciftci, Y. O.; Surucu, G.

    2016-08-01

    We have explored the structural, electronic, optical, and mechanical properties of the magnesium-based chalcopyrites MgSiP2, MgSiAs2, and MgSiSb2 using density functional theory with five different generalized gradient approximation (GGA) functionals: Perdew-Wang (1991), Perdew-Burke-Ernzerhof, revised Perdew-Burke-Ernzerhof, modified Perdew-Burke-Ernzerhof for solids, and Armiento-Mattson (2005) as well as the local density approximation. Change of the constituent element from P to Sb significantly affected the lattice constants, elastic constants, and thermal and dielectric properties. Our theoretically computed results are in reasonable agreement with experiments and other theoretical calculations. The electronic band structure results imply that all three considered compounds are semiconductors. MgSiP2 has the highest value of elastic constants, and bulk and shear moduli compared with the other two binary chalcopyrites. Furthermore, the optical response in terms of the dielectric functions, optical reflectivity, refractive index, extinction coefficient, and electron energy loss of the compounds were also investigated in the energy range from 0 eV to 15 eV. The calculated optical results reveal optical polarization anisotropy for all three compounds, making them useful for optoelectronic device applications. Moreover, specific focus is also given to quantify the dependence of various thermal properties on finite pressure/temperature within the quasiharmonic approximation.

  9. An insight into the mechanism of charge-transfer of hybrid polymer:ternary/quaternary chalcopyrite colloidal nanocrystals

    Directory of Open Access Journals (Sweden)

    Parul Chawla

    2014-08-01

    Full Text Available In this work, we have demonstrated the structural and optoelectronic properties of the surface of ternary/quaternary (CISe/CIGSe/CZTSe chalcopyrite nanocrystallites passivated by tri-n-octylphosphine-oxide (TOPO and tri-n-octylphosphine (TOP and compared their charge transfer characteristics in the respective polymer: chalcopyrite nanocomposites by dispersing them in poly(3-hexylthiophene polymer. It has been found that CZTSe nanocrystallites due to their high crystallinity and well-ordered 3-dimensional network in its pristine form exhibit a higher steric- and photo-stability, resistance against coagulation and homogeneity compared to the CISe and CIGSe counterparts. Moreover, CZTSe nanocrystallites display efficient photoluminescence quenching as evident from the high value of the Stern–Volmer quenching constant (KSV and eventually higher charge transfer efficiency in their respective polymer P3HT:CZTSe composites. We modelled the dependency of the charge transfer from the donor and the charge separation mechanism across the donor–acceptor interface from the extent of crystallinity of the chalcopyrite semiconductors (CISe/CIGSe/CZTSe. Quaternary CZTSe chalcopyrites with their high crystallinity and controlled morphology in conjunction with regioregular P3HT polymer is an attractive candidate for hybrid solar cells applications.

  10. Mechanism of electro-generating leaching of chalcopyrite-MnO2 in presence of Acidithiobacillus thiooxidans

    Institute of Scientific and Technical Information of China (English)

    XIAO Li; LIU Jian-she; FANG Zheng; QIU Guan-zhou

    2008-01-01

    A dual cell system with chalcopyrite anode and MnO2 cathode was used to study the relations between time and such data as the electric quantity and the dissolution rates of the two minerals in the electro-generating leaching(EGL) and the bio-electro-generating leaching(BEGL),respectively.The results showed that the dissolution rates for Cu2+ and Fe2+ in BEGL were almost 2 times faster than those in EGL,and nearly 3 times for Mn2+; the electric output increased nearly by 3 times.The oxidation residue of chalcopyrite was represented by TEM and XRD,whose pattern was similar to that of the raw ore in EGL.The mechanism for leaching of CuFeS2-MnO2 in the presence of Acidithiobacillus thiooxidans was proposed as a successive reaction of two independent sub-processes for the anode.The first stage,common to both processes,is dissolution of chalcopyrite to produce Cu2+,Fe2+ and sulfur.The second stage is subsequent oxidization of sulfur only in BEGL,which is the controlling step of the process.However,the dissolution of MnO2 lasts until the reaction of chalcopyrite stops or the ores exhaust in two types of leaching.

  11. Kinetics and Mechanisms of Chalcopyrite Dissolution at Controlled Redox Potential of 750 mV in Sulfuric Acid Solution

    Directory of Open Access Journals (Sweden)

    Yubiao Li

    2016-08-01

    Full Text Available To better understand chalcopyrite leach mechanisms and kinetics, for improved Cu extraction during hydrometallurgical processing, chalcopyrite leaching has been conducted at solution redox potential 750 mV, 35–75 °C, and pH 1.0 with and without aqueous iron addition, and pH 1.5 and 2.0 without aqueous iron addition. The activation energy (Ea values derived indicate chalcopyrite dissolution is initially surface chemical reaction controlled, which is associated with the activities of Fe3+ and H+ with reaction orders of 0.12 and −0.28, respectively. A surface diffusion controlled mechanism is proposed for the later leaching stage with correspondingly low Ea values. Surface analyses indicate surface products (predominantly Sn2− and S0 did not inhibit chalcopyrite dissolution, consistent with the increased surface area normalised leach rate during the later stage. The addition of aqueous iron plays an important role in accelerating Cu leaching rates, especially at lower temperature, primarily by reducing the length of time of the initial surface chemical reaction controlled stage.

  12. An insight into the mechanism of charge-transfer of hybrid polymer:ternary/quaternary chalcopyrite colloidal nanocrystals.

    Science.gov (United States)

    Chawla, Parul; Singh, Son; Sharma, Shailesh Narain

    2014-01-01

    In this work, we have demonstrated the structural and optoelectronic properties of the surface of ternary/quaternary (CISe/CIGSe/CZTSe) chalcopyrite nanocrystallites passivated by tri-n-octylphosphine-oxide (TOPO) and tri-n-octylphosphine (TOP) and compared their charge transfer characteristics in the respective polymer: chalcopyrite nanocomposites by dispersing them in poly(3-hexylthiophene) polymer. It has been found that CZTSe nanocrystallites due to their high crystallinity and well-ordered 3-dimensional network in its pristine form exhibit a higher steric- and photo-stability, resistance against coagulation and homogeneity compared to the CISe and CIGSe counterparts. Moreover, CZTSe nanocrystallites display efficient photoluminescence quenching as evident from the high value of the Stern-Volmer quenching constant (K SV) and eventually higher charge transfer efficiency in their respective polymer P3HT:CZTSe composites. We modelled the dependency of the charge transfer from the donor and the charge separation mechanism across the donor-acceptor interface from the extent of crystallinity of the chalcopyrite semiconductors (CISe/CIGSe/CZTSe). Quaternary CZTSe chalcopyrites with their high crystallinity and controlled morphology in conjunction with regioregular P3HT polymer is an attractive candidate for hybrid solar cells applications.

  13. Bacterial consortium for copper extraction from sulphide ore consisting mainly of chalcopyrite

    Directory of Open Access Journals (Sweden)

    E. Romo

    2013-01-01

    Full Text Available The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Leptospirillum ferriphilum were isolated and the assays were performed with individual bacteria and in combination with At. thiooxidans. In conclusion, it was found that the consortium integrated by At. ferrooxidans and At. thiooxidans removed 70% of copper in 35 days from the selected ore, showing significant differences with the other consortia, which removed only 35% of copper in 35 days. To validate the assays was done an escalation in columns, where the bacterial consortium achieved a higher percentage of copper extraction regarding to control.

  14. Elastic properties and bonding of the AgGaSe{sub 2} chalcopyrite

    Energy Technology Data Exchange (ETDEWEB)

    Ouahrani, Tarik, E-mail: tarik_ouahrani@hotmail.co [Laboratoire de Physique Theorique, B.P. 119, Universie de Tlemcen, 13000 Tlemcen (Algeria); Otero-de-la-Roza, Alberto [Departamento de Quimica Fisica y Analitica, Universidad de Oviedo, 33006 Oviedo (Spain); Reshak, A.H. [Institute of Physical Biology, South Bohemia University, Nove Hrady 37333 (Czech Republic); Institute of Nano Electronic Engineering, University Malaysia Perlis, 01000 Kangar, Perlis (Malaysia); Khenata, R., E-mail: khenata_rabah@yahoo.f [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Universite de Mascara, 29000 Mascara (Algeria); Department of Physics and Astronomy, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Faraoun, H.I. [Laboratoire d' Etude et Prediction de Materiaux, LEPM-URMER, Universite de Tlemcen, 13000 Tlemcen (Algeria); Amrani, B. [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Universite de Mascara, 29000 Mascara (Algeria); Mebrouki, M. [Laboratoire de Physique Theorique, B.P. 119, Universie de Tlemcen, 13000 Tlemcen (Algeria); Luana, Victor, E-mail: victor@carbono.quimica.uniovi.e [Departamento de Quimica Fisica y Analitica, Universidad de Oviedo, 33006 Oviedo (Spain)

    2010-09-01

    Full-potential linearized augmented plane waves (FPLAPW) calculations have been used to determine the equilibrium properties and elastic constants of the chalcopyrite phase of AgGaSe{sub 2}. The topological analysis of the electron density shows a clear polar bonding, with the integrated basin charges revealing a clear dominance of the covalent over the ionic character. The bonding analysis also provides a partition of the bulk modulus and compressibility into atomic contributions. Se is seen to dominate the global behavior (B=51.2 GPa), with a local bulk modulus intermediate between the values of the other two atoms: 44.8 (Ga), 51.1 (Se), and 56.6 GPa (Ag).

  15. Solution-processed In2S3 buffer layer for chalcopyrite thin film solar cells

    Directory of Open Access Journals (Sweden)

    Wang Lan

    2016-01-01

    Full Text Available We report a route to deposit In2S3 thin films from air-stable, low-cost molecular precursor inks for Cd-free buffer layers in chalcopyrite-based thin film solar cells. Different precursor compositions and processing conditions were studied to define a reproducible and robust process. By adjusting the ink properties, this method can be applied in different printing and coating techniques. Here we report on two techniques, namely spin-coating and inkjet printing. Active area efficiencies of 12.8% and 12.2% have been achieved for In2S3-buffered solar cells respectively, matching the performance of CdS-buffered cells prepared with the same batch of absorbers.

  16. Solution-processed In2S3 buffer layer for chalcopyrite thin film solar cells

    Science.gov (United States)

    Wang, Lan; Lin, Xianzhong; Ennaoui, Ahmed; Wolf, Christian; Lux-Steiner, Martha Ch.; Klenk, Reiner

    2016-02-01

    We report a route to deposit In2S3 thin films from air-stable, low-cost molecular precursor inks for Cd-free buffer layers in chalcopyrite-based thin film solar cells. Different precursor compositions and processing conditions were studied to define a reproducible and robust process. By adjusting the ink properties, this method can be applied in different printing and coating techniques. Here we report on two techniques, namely spin-coating and inkjet printing. Active area efficiencies of 12.8% and 12.2% have been achieved for In2S3-buffered solar cells respectively, matching the performance of CdS-buffered cells prepared with the same batch of absorbers.

  17. Bacterial consortium for copper extraction from sulphide ore consisting mainly of chalcopyrite.

    Science.gov (United States)

    Romo, E; Weinacker, D F; Zepeda, A B; Figueroa, C A; Chavez-Crooker, P; Farias, J G

    2013-01-01

    The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Leptospirillum ferriphilum) were isolated and the assays were performed with individual bacteria and in combination with At. thiooxidans. In conclusion, it was found that the consortium integrated by At. ferrooxidans and At. thiooxidans removed 70% of copper in 35 days from the selected ore, showing significant differences with the other consortia, which removed only 35% of copper in 35 days. To validate the assays was done an escalation in columns, where the bacterial consortium achieved a higher percentage of copper extraction regarding to control.

  18. Bacterial consortium for copper extraction from sulphide ore consisting mainly of chalcopyrite

    Science.gov (United States)

    Romo, E.; Weinacker, D.F.; Zepeda, A.B.; Figueroa, C.A.; Chavez-Crooker, P.; Farias, J.G.

    2013-01-01

    The mining industry is looking forward for bacterial consortia for economic extraction of copper from low-grade ores. The main objective was to determine an optimal bacterial consortium from several bacterial strains to obtain copper from the leach of chalcopyrite. The major native bacterial species involved in the bioleaching of sulphide ore (Acidithiobacillus ferrooxidans, Acidithiobacillus thiooxidans, Leptospirillum ferrooxidans and Leptospirillum ferriphilum) were isolated and the assays were performed with individual bacteria and in combination with At. thiooxidans. In conclusion, it was found that the consortium integrated by At. ferrooxidans and At. thiooxidans removed 70% of copper in 35 days from the selected ore, showing significant differences with the other consortia, which removed only 35% of copper in 35 days. To validate the assays was done an escalation in columns, where the bacterial consortium achieved a higher percentage of copper extraction regarding to control. PMID:24294251

  19. Adiabatic bond charge model for lattice dynamics of ternary chalcopyrite semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Guerel, T.; Eryigit, R. [Department of Physics, Abant Izzet Baysal University, Bolu, 14280 (Turkey)

    2006-01-01

    The adiabatic bond charge model of Rustagi and Weber is extended to study lattice dynamical properties of ternary chalcopyrite semiconductors AgGaS{sub 2}, AgGaSe{sub 2}, CuInS{sub 2}, CuInSe{sub 2}, CuGaS{sub 2}, CuGaSe{sub 2}, CuAlS{sub 2} and CuAlSe{sub 2}. The new model calculations agree well with the results of Raman/IR and neutron measurements of Brillouin zone center phonon frequencies for both low and high frequency modes which was difficult for other phenomenological lattice dynamical models. (copyright 2005 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  20. STRUCTURAL PHASE TRANSITION, ELASTIC AND ELECTRONIC PROPERTIES OF CuXSe2(X = In, Ga) CHALCOPYRITE

    Science.gov (United States)

    Bouguetaia, T.; Abidri, B.; Benbahi, B.; Rached, D.; Hiadsi, S.; Rabah, M.

    2012-04-01

    The structural, elastic and electronic properties of chalcopyrite compound CuInSe2 and CuGaSe2 have been investigated using the full-potential linearized muffin-tin orbital method (FP-LMTO) within the frame of density functional theory (DFT). In this approach, the local density approximation is used for the exchange-correlation potential using Perdew-Wang parametrization. The equilibrium lattice parameters, bulk modulus, transition pressure, elastic constants and their related parameters such as Poisson's ratio, Young modulus, shear modulus and Debye temperature were calculated and compared with available experimental and theoretical data. They are in reasonable agreement. In this paper the electronic properties are treated with GGA + U approach, which brings out the important role played by the d-state of noble metal (Cu) and give the correct nature of the energy band gap. Our obtained results show that both compounds exhibit semi-conductor behaviour with direct band gap.

  1. Changes in biofilm structure during the colonization of chalcopyrite by Acidithiobacillus thiooxidans.

    Science.gov (United States)

    García-Meza, J V; Fernández, J J; Lara, R H; González, I

    2013-07-01

    Biofilms of Acidithiobacillus thiooxidans were grown on the surface of massive chalcopyrite electrodes (MCE) where different secondary sulfur phases were previously formed by potentiostatic oxidation of MCE at 0.780≤Ean≤0.965 V (electrooxidized MCE, eMCE). The formation of mainly S⁰ and minor amounts of CuS and Sn²⁻ were detected on eMCEs. The eMCEs were incubated with A. thiooxidans cells for 1, 12, 24, 48, and 120 h in order to temporally monitor changes in eMCE's secondary phases, biofilm structure, and extracellular polymeric substance (EPS) composition (lipids, proteins, and polysaccharides) using microscopic, spectroscopic, electrochemical, and biochemical techniques. The results show significant cell attachments with stratified biofilm structure since the first hour of incubation and EPS composition changes, the most important being production after 48-120 h when the highest amount of lipids and proteins were registered. During 120 h, periodic oxidation/formation of S⁰/Sn²⁻ was recorded on biooxidized eMCEs, until a stable CuS composition was formed. In contrast, no evidence of CuS formation was observed on the eMCEs of the abiotic control, confirming that CuS formation results from microbial activity. The surface transformation of eMCE induces a structural transformation of the biofilm, evolving directly to a multilayered biofilm with more hydrophobic EPS and proteins after 120 h. Our results suggest that A. thiooxidans responded to the spatial and temporal distribution and chemical reactivity of the Sn²⁻/S⁰/CuS phases throughout 120 h. These results suggested a strong correlation between surface speciation, hydrophobic domains in EPS, and biofilm organization during chalcopyrite biooxidation by A. thiooxidans.

  2. Fabrication of dye sensitized solar cell using Cr doped Cu-Zn-Se type chalcopyrite thin film

    Energy Technology Data Exchange (ETDEWEB)

    Joseph, D. Paul; Venkateswaran, C. [Materials Science Centre, Department of Nuclear Physics, University of Madras, Guindy Campus, Chennai-600 025 (India); Ganesan, S.; Suthanthiraraj, S. Austin; Maruthamuthu, P. [Department of Energy, University of Madras, Guindy Campus, Chennai 600 025 (India); Kovendhan, M. [Department of Physics, Presidency College, Chennai 600 005 (India)

    2011-09-15

    Chalcopyrites are a versatile class of semiconductors known for their potential in photovoltaic applications. Considering the well established CuInSe{sub 2} as a prototype system, a new compound of the chalcopyrite type, Cu{sub 1-x}Zn{sub 1-y}Se{sub 2-{delta}}, by replacing In with Zn, has been prepared (both undoped and 2% Cr doped) by the metallurgical method. Thin films have been deposited by the thermal evaporation technique using the stabilized polycrystalline compounds as charge. Structural, compositional, morphological, and optical properties of the films are analyzed and reported. Use of these films as electrodes in dye sensitized solar cell (DSSC) is demonstrated. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Effect of pH values on the extracellular polysaccharide secreted by Acidithiobacillus ferrooxidans during chalcopyrite bioleaching

    Institute of Scientific and Technical Information of China (English)

    Run-lan Yu; Jing Liu; Jian-xi Tan; Wei-min Zeng; Li-juan Shi; Guo-hua Gu; Wen-qing Qin; Guan-zhou Qiu

    2014-01-01

    The pH value plays an important role in the bioleaching of sulphide minerals. The effect of pH values on the extracellular poly-saccharide secreted by Acidithiobacillus ferrooxidans was investigated in different phases of bacterial growth during chalcopyrite bioleach-ing. It is found that extracellular polysaccharide secretion from the cells attached to chalcopyrite is more efficiently than that of the free cells in the bioleaching solution. Three factors, pH values, the concentration of soluble metal ions, and the bacterial growth and metabolism, affect extracellular polysaccharide secretion in the free cells, and are related to the bacterial growth phase. Extracellular polysaccharide secretion from the attached cells is mainly dependent on the pH value of the bacterial culture.

  4. Community dynamics of attached and free cells and the effects of attached cells on chalcopyrite bioleaching by Acidithiobacillus sp.

    Science.gov (United States)

    Yang, Hailin; Feng, Shoushuai; Xin, Yu; Wang, Wu

    2014-02-01

    The community dynamics of attached and free cells of Acidithiobacillus sp. were investigated and compared during chalcopyrite bioleaching process. In the mixed strains system, Acidithiobacillus ferrooxidans was the dominant species at the early stage while Acidithiobacillus thiooxidans owned competitive advantage from the middle stage to the end of bioprocess. Meanwhile, compared to A. ferrooxidans, more significant effects of attached cells on free biomass with A. thiooxidans were shown in either the pure or mixed strains systems. Moreover, the effects of attached cells on key chemical parameters were also studied in different adsorption-deficient systems. Consistently, the greatest reduction of key chemical ion was shown with A. thiooxidans and the loss of bioleaching efficiency was high to 50.5%. These results all demonstrated the bioleaching function of attached cells was more efficient than the free cells, especially with A. thiooxidans. These notable results would help us to further understand the chalcopyrite bioleaching.

  5. Valence band gaps and plasma energies for galena, sphalerite, and chalcopyrite natural minerals using differential optical reflectance spectroscopy

    Science.gov (United States)

    Todoran, R.; Todoran, D.; Szakacs, Zs.

    2015-12-01

    The paper presents the determinations of the valence band gaps and plasma energies of the galena, sphalerite and chalcopyrite natural minerals. The work was carried out using differential optical reflectance spectroscopy of the clean mineral surfaces. The determination of the optical properties such as refractive index, real part of the complex dielectric constant and the location of certain van Hove singularities, was carried out using the Kramers-Kronig formalism.

  6. Dependence of Ionicity and Thermal Expansion Coefficient on Valence Electron Density in AIIBIVC2V Chalcopyrite Semiconductors

    Directory of Open Access Journals (Sweden)

    Amar BAHADUR

    2013-06-01

    Full Text Available A striking correlation has been found to exist between the free electron density parameter, average bond length, homoplar energy gap, heteropolar energy gap, ionicity and thermal expansion coefficient for AIIBIVC2V chalcopyrite semiconductors. The estimated values of these parameters are in good agreement with the available experimental values and theoretical findings. The electron density parameter data is the only one input data to estimate all above properties.

  7. Photoreflectance spectroscopy of the chalcopyrite semiconductor AgInS 2 for ordinary and extraordinary rays

    Science.gov (United States)

    Ozaki, S.; Horikoshi, Y.

    2016-06-01

    Photoreflectance spectra have been measured on the chalcopyrite semiconductor silver indium disulfide ({AgInS}2) for light polarization {\\varvec{E}} perpendicular ({\\varvec{E}} bot {c}) and parallel to the c-axis ({\\varvec{E}} \\vert \\vert {c}) at temperature between 10 and 300 K. The measured photoreflectance spectra revealed distinct structures at 1.8-2.1 eV. The lowest bandgap energies E_{0A}, E_{0B}, and E_{0C} of {AgInS}2 show unusual temperature dependence at low temperatures (≤140 K). The E_{0α } (α =A, B, C) is found to increase with increasing temperature from 10 to ˜140 K and decreases with a further increase in temperature. This result has been successfully explained by taking into account the effects of thermal expansion and electron-phonon interaction. The spin-orbit and crystal-field splitting parameters of {AgInS}2 are determined to be Δ _{{so}}=38 meV and Δ _{{cr}}=-168 meV at T = 10 K, respectively, and are discussed from an aspect of the electronic energy band structure consequences. The temperature dependence of spin-orbit and crystal-field splitting parameters of {AgInS}2 was also presented.

  8. Conducting behavior of chalcopyrite-type CuGaS₂ crystals under visible light.

    Science.gov (United States)

    Cholula-Díaz, Jorge L; Barzola-Quiquia, José; Kranert, Christian; Michalsky, Tom; Esquinazi, Pablo; Grundmann, Marius; Krautscheid, Harald

    2014-10-21

    Millimeter size high quality crystals of CuGaS2 were grown by chemical vapor transport. The highly ordered chalcopyrite structure is confirmed by X-ray diffraction and Raman spectroscopy. According to energy dispersive X-ray spectroscopy the composition of the crystals is very close to the formula CuGaS2. Room temperature photoluminescence measurements indicate the presence of an emission peak at about 2.36 eV that can be related to a donor-acceptor pair transition. The electrical resistance as a function of temperature is very well described by the Mott variable range hopping mechanism. Room temperature complex impedance spectroscopy measurements were performed in the alternating current frequency range from 40 to 10(7) Hz in the dark and under normal light. According to the impedance spectroscopy data the experimental results can be well described by two circuits in series, corresponding to bulk and grain boundary contributions. An unusual positive photoresistance effect is observed in the frequency range between 3 and 30 kHz, which we suggest to be due to intrinsic defects present in the CuGaS2 crystal.

  9. Experimental indication for band gap widening of chalcopyrite solar cell absorbers after potassium fluoride treatment

    Energy Technology Data Exchange (ETDEWEB)

    Pistor, P., E-mail: paul.pistor@physik.uni-halle.de [Martin-Luther-Universität Halle, Von-Danckelmann-Platz 3, 06120 Halle (Germany); Greiner, D.; Kaufmann, C. A.; Brunken, S.; Gorgoi, M.; Steigert, A.; Calvet, W.; Lauermann, I.; Klenk, R.; Unold, T.; Lux-Steiner, M.-C. [Helmholtz-Zentrum Berlin, Hahn-Meitner-Platz 1, 14109 Berlin (Germany)

    2014-08-11

    The implementation of potassium fluoride treatments as a doping and surface modification procedure in chalcopyrite absorber preparation has recently gained much interest since it led to new record efficiencies for this kind of solar cells. In the present work, Cu(In,Ga)Se{sub 2} absorbers have been evaporated on alkali containing Mo/soda-lime glass substrates. We report on compositional and electronic changes of the Cu(In,Ga)Se{sub 2} absorber surface as a result of a post deposition treatment with KF (KF PDT). In particular, by comparing standard X-ray photoelectron spectroscopy and synchrotron-based hard X-ray photoelectron spectroscopy (HAXPES), we are able to confirm a strong Cu depletion in the absorbers after the KF PDT which is limited to the very near surface region. As a result of the Cu depletion, we find a change of the valence band structure and a shift of the valence band onset by approximately 0.4 eV to lower binding energies which is tentatively explained by a band gap widening as expected for Cu deficient compounds. The KF PDT increased the open circuit voltage by 60–70 mV compared to the untreated absorbers, while the fill factor deteriorated.

  10. A stochastic model of solid state thin film deposition: Application to chalcopyrite growth

    Directory of Open Access Journals (Sweden)

    Robert J. Lovelett

    2016-04-01

    Full Text Available Developing high fidelity quantitative models of solid state reaction systems can be challenging, especially in deposition systems where, in addition to the multiple competing processes occurring simultaneously, the solid interacts with its atmosphere. In this work, we develop a model for the growth of a thin solid film where species from the atmosphere adsorb, diffuse, and react with the film. The model is mesoscale and describes an entire film with thickness on the order of microns. Because it is stochastic, the model allows us to examine inhomogeneities and agglomerations that would be impossible to characterize with deterministic methods. We demonstrate the modeling approach with the example of chalcopyrite Cu(InGa(SeS2 thin film growth via precursor reaction, which is a common industrial method for fabricating thin film photovoltaic modules. The model is used to understand how and why through-film variation in the composition of Cu(InGa(SeS2 thin films arises and persists. We believe that the model will be valuable as an effective quantitative description of many other materials systems used in semiconductors, energy storage, and other fast-growing industries.

  11. Acidithiobacillus thiooxidans secretome containing a newly described lipoprotein Licanantase enhances chalcopyrite bioleaching rate.

    Science.gov (United States)

    Bobadilla Fazzini, Roberto A; Levican, Gloria; Parada, Pilar

    2011-02-01

    The nature of the mineral-bacteria interphase where electron and mass transfer processes occur is a key element of the bioleaching processes of sulfide minerals. This interphase is composed of proteins, metabolites, and other compounds embedded in extracellular polymeric substances mainly consisting of sugars and lipids (Gehrke et al., Appl Environ Microbiol 64(7):2743-2747, 1998). On this respect, despite Acidithiobacilli-a ubiquitous bacterial genera in bioleaching processes (Rawlings, Microb Cell Fact 4(1):13, 2005)-has long been recognized as secreting bacteria (Jones and Starkey, J Bacteriol 82:788-789, 1961; Schaeffer and Umbreit, J Bacteriol 85:492-493, 1963), few studies have been carried out in order to clarify the nature and the role of the secreted protein component: the secretome. This work characterizes for the first time the sulfur (meta)secretome of Acidithiobacillus thiooxidans strain DSM 17318 in pure and mixed cultures with Acidithiobacillus ferrooxidans DSM 16786, identifying the major component of these secreted fractions as a single lipoprotein named here as Licanantase. Bioleaching assays with the addition of Licanantase-enriched concentrated secretome fractions show that this newly found lipoprotein as an active protein additive exerts an increasing effect on chalcopyrite bioleaching rate.

  12. Improved chalcopyrite bioleaching by Acidithiobacillus sp. via direct step-wise regulation of microbial community structure.

    Science.gov (United States)

    Feng, Shoushuai; Yang, Hailin; Wang, Wu

    2015-09-01

    A direct step-wise regulation strategy of microbial community structure was developed for improving chalcopyrite bioleaching by Acidithiobacillus sp. Specially, the initial microbial proportion between Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans was controlled at 3:1 with additional 2 g/L Fe(2+) for faster initiating iron metabolism. A. thiooxidans biomass was fed via a step-wise strategy (8-12th d) with the microbial proportion 1:1 for balancing community structure and promoting sulfur metabolism in the stationary phase. A. thiooxidans proportion was further improved via another step-wise feeding strategy (14-18th d) with the microbial proportion 1:2 for enhancing sulfur metabolism and weakening jarosite passivation in the later phase. With the community structure-shift control strategy, biochemical reaction was directly regulated for creating a better balance in different phases. Moreover, the final copper ion was increased from 57.1 to 93.2 mg/L, with the productivity 2.33 mg/(Ld). The novel strategy may be valuable in optimization of similar bioleaching process.

  13. Structural, electronic, linear, and nonlinear optical properties of ZnCdTe{sub 2} chalcopyrite

    Energy Technology Data Exchange (ETDEWEB)

    Ouahrani, Tarik [Laboratoire de Physique Theorique, Universite de Tlemcen, B.P. 230, Tlemcen 13000 (Algeria); Reshak, Ali H. [Institute of Physical Biology, South Bohemia University, Nove Hrady 37333 (Czech Republic); School of Microelectronic Engineering, University of Malaysia Perlis (UniMAP), Block A, Kompleks Pusat Pengajian, 02600 Arau Jejawi, Perlis (Malaysia); Khenata, R. [Laboratoire de Physique Quantique et de Modelisation Mathematique, Universite de Mascara, Mascara 29000 (Algeria); Department of Physics and Astronomy, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Baltache, H.; Amrani, B. [Laboratoire de Physique Quantique et de Modelisation Mathematique, Universite de Mascara, Mascara 29000 (Algeria); Bouhemadou, A. [Department of Physics and Astronomy, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Faculty of Sciences, Department of Physics, University of Setif, Setif 19000 (Algeria)

    2011-03-15

    We report results of first-principles density functional calculations using the full-potential linearized augmented plane wave method. The generalized gradient approximation (GGA) and the Engel-Vosko-GGA (EV-GGA) formalism were used for the exchange-correlation energy to calculate the structural, electronic, linear, and nonlinear optical properties of the chalcopyrite ZnCdTe{sub 2} compound. The valence band maximum and the conduction band minimum are located at the {gamma}-point, resulting in a direct band gap of about 0.71 eV for GGA and 1.29 eV for EV-GGA. The results of bulk properties, such as lattice parameters (a, c, and u), bulk modulus B, and its pressure derivative B' are evaluated. The optical properties of this compound, namely the real and the imaginary parts of the dielectric function, reflectivity, and refractive index, show a considerable anisotropy as a consequence ZnCdTe{sub 2} posseses a strong birefringence. In addition, the extinction coefficient, the electron energy loss function, and the nonlinear susceptibility are calculated and their spectra are analyzed. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  14. Theoretical investigation on thermoelectric properties of Cu-based chalcopyrite compounds

    Science.gov (United States)

    Wang, Biao; Xiang, Hongjun; Nakayama, Tsuneyoshi; Zhou, Jun; Li, Baowen

    2017-01-01

    Cu-based materials are potential candidates for commercial thermoelectric materials due to their abundance, nontoxicity, and high performance. We incorporate the multiband Boltzmann transport equations with first-principles calculations to theoretically investigate the thermoelectric properties of Cu-based chalcopyrite compounds. As a demonstration of our method, the thermoelectric properties of quaternary compounds Cu2ZnSnX4 (X = S, Se) and ternary compounds CuBTe2 (B = Ga, In) are studied. We systematically calculate the electrical conductivity, the Seebeck coefficient, and the power factor of the four materials above based on parameters obtained from first-principles calculations and using several other fitting parameters. For quaternary compounds, our results reveal that Cu2ZnSnSe4 is better than Cu2ZnSnS4 and its optimal hole concentration is around 5 ×1019cm-3 with the peak power factor 4.7 μ W/cm K 2 at 600 K. For ternary compounds, we find that their optimal hole concentrations are around 1 ×1020cm-3 with the peak power factors over 26 μ W/cm K 2 at 800 K.

  15. Fe and Cu isotope fractionation between chalcopyrite and dissolved metal species during hydrothermal recrystallization: An experimental study at 350°C and 500 bars

    Science.gov (United States)

    Syverson, D. D.; Luhmann, A. J.; Tan, C.; Borrok, D. M.; Ding, K.; Seyfried, W. E., Jr.

    2015-12-01

    The equilibrium Fe and Cu isotope fractionation factor between chalcopyrite and dissolved metal species was determined under hydrothermal conditions at 350°C and 500 bars. The experiments took advantage of gold-cell reaction technology, allowing time-series sampling of solution during the hydrothermal recrystallization of chalcopyrite over 3000 hours. One of the recrystallization experiments utilized an anomalous 57Fe spike in solution to quantify the degree and rate of isotopic exchange towards equilibrium between mineral and fluid reservoirs. The time-series 57Fe spike data suggests that chalcopyrite exchanges rapidly with dissolved Fe and Cu in solution and the isotopic fractionation between each metal-bearing reservoir throughout reaction progress, upon dissolution and recrystallization, represents close to equilibrium conditions. The isotope data indicate that the equilibrium fractionation between chalcopyrite and dissolved Fe and Cu at 350°C, Δ56FeCpy-Fe(aq), is 0.129±0.171‰ and Δ65CuCpy-Fe(aq), is -0.201±0.341‰ (2σ), and are in good agreement with recent theoretical equilibrium predictions. Comparison of the experimental data from this study with conjugate chalcopyrite and dissolved Fe and Cu pairs from a variety of hydrothermal systems along the mid-ocean ridge system indicates that chalcopyrite precipitates and recrystallizes at isotopic equilibrium with the fluid during cooling upon ascent to the seafloor. The rapid exchange between the mineral and fluid metal-reservoirs suggests that chalcopyrite effectively records the isotopic composition of the coexisting hydrothermal fluid during the evolution of hydrothermal systems. In addition, the pyrite-chalcopyrite equilibrium Fe isotope fractionation, Δ56FePyr-Cpy, at 350°C is quantified by combination of pyrite-Fe2+(aq) equilibrium fractionation data from Syverson et al., [2013] with chalcopyrite-Fe2+(aq) from this study, resulting in a fractionation of 0.861±0.337‰ (2σ). The empirical

  16. Fe isotope fractionation between chalcopyrite and dissolved Fe during hydrothermal recrystallization: An experimental study at 350 °C and 500 bars

    Science.gov (United States)

    Syverson, Drew D.; Luhmann, Andrew J.; Tan, Chunyang; Borrok, David M.; Ding, Kang; Seyfried, William E.

    2017-03-01

    Equilibrium Fe isotope fractionation between chalcopyrite and dissolved Fe was determined in acidic chloride-bearing fluid at 350 °C and 500 bars. The study utilized deformable gold-cell technology, which allowed time-series sampling of solution during chalcopyrite recrystallization and isotope exchange. A key element of the experimental design involved the addition of anomalous dissolved 57Fe to an on-going experiment as a means of determining the degree and rate of isotope exchange. Taking explicit account of imposed chemical and isotopic mass balance constraints of Fe in fluid and mineral (chalcopyrite) reservoirs, these data indicate that no more than 1000 h is required for the isotopically anomalous dissolved Fe reservoir to exchange completely with the coexisting chalcopyrite. The experimental calibration of the rate of Fe isotope exchange for the δ57Fe-spiked experiment provides critical insight for the time necessary to achieve Fe isotope exchange in two non-spiked, but otherwise identical experiments. The Fe isotope data indicate that the equilibrium fractionation between chalcopyrite and dissolved Fe, Δ56FeCpy-Fe (aq), at 350 °C is small, 0.09 ± 0.17‰ (2σ), and is in good agreement with recent theoretical equilibrium predictions. Owing to the apparent rate of Fe isotope exchange at 350 °C, it is likely that chalcopyrite formed at high temperature deep-sea vents (black smoker systems) achieves isotopic equilibrium, and effectively records the Fe isotopic composition of the coexisting end-member hydrothermal fluid. Comparison of the experimental mineral-fluid equilibrium fractionation factors with conjugate chalcopyrite and dissolved Fe pairs sampled from high temperature hydrothermal vent systems at Axial Caldera and Main Endeavour Field (Juan de Fuca Ridge) are in agreement with this inference. The experimental data were further used to determine the mineral-mineral equilibrium Fe isotope fractionation between pyrite-chalcopyrite, Δ56Fe

  17. Correlating the Local Defect-Level Density with the Macroscopic Composition and Energetics of Chalcopyrite Thin-Film Surfaces.

    Science.gov (United States)

    Bröker, Sebastian; Kück, Dennis; Timmer, Alexander; Lauermann, Iver; Ümsür, Bünyamin; Greiner, Dieter; Kaufmann, Christian A; Mönig, Harry

    2015-06-17

    The unusual defect chemistry of polycrystalline Cu(In,Ga)Se2 (CIGSe) thin films is a main issue for a profound understanding of recombination losses in chalcopyrite thin-film solar cells. Especially, impurity-driven passivation of electronic levels due to point defects segregating at the surface and at grain boundaries is extensively debated. By combining current imaging tunneling spectroscopy with photoelectron spectroscopy, the local defect-level density and unusual optoelectronic grain-boundary properties of this material are correlated with the macroscopic energy levels and surface composition. Vacuum annealing of different CIGSe materials provides evidence that Na diffusion from the glass substrate does not affect the surface defect passivation or grain-boundary properties of standard Cu-poor materials. Furthermore, we find no major impact on the observed thermally activated dipole compensation or the accompanying change in surface band bending (up to 0.6 eV) due to Na. In contrast, Cu-rich CIGSe shows an opposing surface defect chemistry with only minor heat-induced band bending. Our results lead to a comprehensive picture, where the highly desirable type inversion at the p/n interface in standard chalcopyrite thin-film solar cells is dominated by band bending within the CIGSe absorber rather than the result of Na impurities or an n-type defect phase segregating at the interface. This is in accordance with recent studies suggesting a surface reconstruction as the origin for Cu depletion and band-gap widening at the surface of chalcopyrite thin films.

  18. Density functional calculation for the first and second harmonic generation of the chalcopyrite Ga2AsSb

    OpenAIRE

    Reshak, Ali H.; OUAHRANI, T.; Khenata, R.; A. Otero-de-la-Roza; Luana, V.; Baltache, H.

    2011-01-01

    An ab initio study of the band structure, density of states, topology of the electron density and the spectral features of the linear and non-linear optical properties of the Ga2AsSb chalcopyrite are presented. The lattice parameters (a, c), the internal structure parameter, u, describing the position of Ga atom and the (c/a) ratio are optimized. The covalent bonding character is predicted via analyzing the electron density at the equilibrium geometry. The linear optical properties namely the...

  19. First and second harmonic generation of the XAl2Se4 (X=Zn,Cd,Hg) defect chalcopyrite compounds

    OpenAIRE

    Ouahrani, Tank; Khenata, R.; Lasri, B; Reshak, Ali H.; Bouhemadou, A.; Bin-Omran, S

    2012-01-01

    The chemical bonding of the ZnAl2Se4, CdAl2Se4 and HgAl2Se4 defect chalcopyrites has been studied in the framework of the quantum theory of atoms in molecules (AIM). The GW quasi-particle approximation is used to correct the DFT-underestimation of energy gap, and as a consequence the linear and nonlinear optical properties are significantly enhanced. The second harmonic generation (SHG) displays certain dependence with the ionicity degree decrease through the dependency of the SHG on the band...

  20. Electronic level alignment at the deeply buried absorber/Mo interface in chalcopyrite-based thin film solar cells

    Science.gov (United States)

    Bär, M.; Nishiwaki, S.; Weinhardt, L.; Pookpanratana, S.; Shafarman, W. N.; Heske, C.

    2008-07-01

    We have investigated the electronic structure of the absorber/back contact interface for S-free [Cu(In ,Ga)Se2 ("CIGSe")] and S-containing [Cu(In ,Ga)(S,Se)2 ("CIGSSe")] chalcopyrites with direct and inverse photoemission. Comparison of the electronic levels of the cleavage planes reveals a pronounced cliff in the conduction band at the CIG(S )Se/Mo interface. For the valence band, we find a flat alignment and a small spike for the CIGSe- and CIGSSe-based structures, respectively.

  1. Nanocrystalline Chalcopyrite Materials (CuInS2 and CuInSe2) via Low-Temperature Pyrolysis of Molecular Single-Source Precursors

    Science.gov (United States)

    Castro, Stephanie L.; Bailey, Sheila G.; Raffaelle, Ryne P.; Banger, Kulbinder K.; Hepp, Aloysius F.

    2003-01-01

    Nanometer sized particles of the chalcopyrite compounds CuInS2 and CuInSe2 were synthesized by thermal decomposition of molecular single-source precursors (PPh3)2CuIn(SEt)4 and (PPh3)2CuIn(SePh)4, respectively, in the non-coordinating solvent dioctyl phthalate at temperatures between 200 and 300 C. The nanoparticles range in size from 3 - 30 nm and are aggregated to form roughly spherical clusters of about 500 nm in diameter. X-ray diffraction of the nanoparticle powders shows greatly broadened lines indicative of very small particle sizes, which is confirmed by TEM. Peaks present in the XRD can be indexed to reference patterns for the respective chalcopyrite compounds. Optical spectroscopy and elemental analysis by energy dispersive spectroscopy support the identification of the nanoparticles as chalcopyrites.

  2. Mathematical model of the chemistry of the dump leaching of chalcopyrite

    Energy Technology Data Exchange (ETDEWEB)

    Liddell, K.C.

    1980-03-01

    In a leach dump, chalcopyrite is dissolved by Fe/sup 3 +/ and by O/sub 2/ and H/sup +/. Neither reaction is at equilibrium under operational conditions. The solution contains Fe(III), Fe(II) and Cu(II) in an aqueous sulfate medium with a pH of about 2. The equilibrium concentrations of H/sup +/, OH/sup -/, SO/sub 4//sup 2 -/, HSO/sub 4//sup -/, Fe/sup 3 +/, FeOH/sup 2 +/, Fe(OH)/sub 2//sup +/, Fe/sub 2/(OH)/sub 2//sup 4 +/, FeSO/sub 4//sup +/, Fe(SO/sub 4/)/sub 2//sup -/, FeHSO/sub 4//sup 2 +/, Fe/sup 2 +/, FeSO/sub 4//sup 0/, FeHSO/sub 4//sup +/, Cu/sup 2 +/ and CuSO/sub 4//sup 0/ were calculated for different Fe/sub 2/(SO/sub 4/)/sub 3/, FeSO/sub 4/, CuSO/sub 4/ and H/sub 2/SO/sub 4/ analytical concentrations using both ideal solution and high ionic strength apparent equilibrium constants. Conditions under which Fe/sup 3 +/ precipitates have been investigated by including K/sub Sp/ values as constraints in the computer program. Jarosite, KFe/sub 3/(SO/sub 4/)/sub 2/(OH)/sub 6/, precipitates except when the K/sup +/ concentration is very small. Formation of goethite, ..cap alpha..-FeOOH, occurs through aging of amorphous Fe(OH)/sub 3/; ferric hydroxide precipitation is favored by high Fe/sup 3 +/ concentrations and high pH. With both dissolution reactions occurring, it was found that the H/sup +/ consumed was partially restored by dissociation of HSO/sub 4//sup -/, FEHSO/sub 4//sup 2 +/ and FeHSO/sub 4//sup +/. With no O/sub 2/ reacting, there were only slight changes in the H/sup +/ and HSO/sub 4//sup -/ concentrations and FeHSO/sub 4//sup +/ was a product. The maximum copper concentration was obtained with high starting Fe/sub 2/(SO/sub 4/)/sub 3/ concentrations and little or no O/sub 2/ consumption. Too large an amount of O/sub 2/ reacting led to pH increases that caused precipitation of Fe(OH)/sub 3/.

  3. Photoelectrochemical hydrogen-evolution over p-type chalcopyrite CuInSe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Djellal, L. [Laboratoire des Solutions Solides, Faculte de Physique, (USTHB) BP 32 El Alia 16111, Algiers (Algeria); Omeiri, S.; Bouguelia, A. [Laboratoire de Stockage et de Valorisation des Energies Renouvelables, Faculte de Chimie, (USTHB) BP 32 El Alia 16111, Algiers (Algeria); Trari, M. [Laboratoire de Stockage et de Valorisation des Energies Renouvelables, Faculte de Chimie, (USTHB) BP 32 El Alia 16111, Algiers (Algeria)], E-mail: mtrari@caramail.com

    2009-05-12

    Photocatalytic H{sub 2}-production has been realized over active CuInSe{sub 2}, synthesized by the fusion technique. The material crystallizes in the chalcopyrite structure and exhibits p-type conductivity ascribed to copper deficiency. An optical gap of 0.95 eV was determined from the reflectance diffuse spectrum. The electrical conductivity follows an Arrhenius-type law with activation energy of 23 meV in conformity with polaron hopping. The slope and the intercept of the Mott-Schottky plot gave a holes density N{sub A} of 5.9 x 10{sup 18} cm{sup -3} and a flat band potential of -0.36V{sub SCE}, in perfect agreement with the photo-onset potential V{sub on} (-0.35V{sub SCE}). Hence, the conduction band, located at -1.29V{sub SCE}, allows a spontaneous H{sub 2} liberation upon visible light. In aqueous solutions, the material is stabilized by hole consumption involving X{sup 2-} species (=S{sup 2-} and SO{sub 3}{sup 2-}). H{sub 2} formation would become thermodynamically easy in alkaline media and the best photoactivity was obtained in thiosulfate electrolyte (10{sup -2} M S{sub 2}O{sub 3}{sup 2-}, 0.5 M KOH) with an evolution rate of 0.009 ml mg{sup -1} h{sup -1}. The light induced electron transfer through the interface involves two steps mechanism where S{sub 2}O{sub 3}{sup 2-} is oxidized to SO{sub 3}{sup 2-} and SO{sub 4}{sup 2-} by successive reactions. Such results are corroborated by the semi logarithmic plots and photocurrent-photopotential characteristics. The influence of pH was studied with S{sub 2}O{sub 3}{sup 2-} The tendency towards saturation for prolonged irradiation is attributed to competitive reductions of the end products S{sub n}{sup 2-} and S{sub 2}O{sub 6}{sup 2-} with water and to the yellow color of polysulfide S{sub n}{sup 2-}.

  4. 黄铜矿生物浸出机制研究进展%Research Progress of Chalcopyrite Bioleaching Mechanism

    Institute of Scientific and Technical Information of China (English)

    曾伟民; 邱冠周

    2012-01-01

    ItS necessary to solve the problem of low efficiency of chalcopyrite bioleaching by the bioleaching mechanism. Reviewed the development progress of bioleaching mechanism from "direct and indirect action" theory to "contact action" theory,then "indirect action-direct contact action-indirect contact action" theory and introduced the correlation model and explanation in detail. The chalcopyrite bioleaching mechanism isnt verdict and needs to continue thorough research.%要解决黄铜矿生物浸出效率较低的难题,需要从生物浸出机制人手.回顾了生物浸出机制从“直接作用”和“间接作用”理论到“接触作用”理论,再到“间接作用-直接接触作用-间接接触作用”理论的发展历程,并对这些理论的相关模型和解释进行了详细介绍.最后指出黄铜矿生物浸出机制尚未定论,还有待于继续深入研究.

  5. Chalcopyrite Intergrowths in sphalerite in the Meixian Lead—Zine Deposit,Fujian Province and their Metallogenic Significance

    Institute of Scientific and Technical Information of China (English)

    顾连兴; 周兵; 等

    1998-01-01

    Ore textures and electron microprobe analyses show that in addition to highly scattered blebs in sphalerite grains,intergrown chalcopyrite also occurs as rods,myrmekites and lamellae aligned along cleavages and twin boundaries of the host sphalerite.The majority of the intergrowths could have been formed by replacement of sphalerite by chalcopyrite,albeit part of them may have resulted from exsolution,Not only copper,but also iron were introduced into the sphalerite by replacive fluids.While the front of the replacing fluid was moving forward through a sulphide orebody,Zn and Pb were dissolved and Cu was precipitated,resulting in zonal refining of the sulphide ores,The remobilized zinc and lead were precipitated at favourable sites with changed physico-chemical conditions .This is a possible mechanism for the formation of copper-poor zinc and lead ores above or lateral to the copper orebodies in some of the massive sulphide deposits reworked and overprinted by late-stage granites and their hydrothermal fluids.

  6. Bioleaching of chalcopyrite concentrate using Leptospirillum ferriphilum, Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans in a continuous bubble column reactor.

    Science.gov (United States)

    Xia, Lexian; Yin, Chu; Dai, Songlin; Qiu, Guanzhou; Chen, Xinhua; Liu, Jianshe

    2010-03-01

    To estimate the bioleaching performance of chalcopyrite for various hydraulic residence times (HRTs), laboratory-scale bioleaching of chalcopyrite concentrate was carried out in a continuous bubble column reactor with three different HRTs of 120, 80 and 40 h, respectively. An extraction rate and ratio of 0.578 g Cu l(-1) h(-1) and 39.7%, respectively, were achieved for an HRT of 80 h at a solids concentration of 10% (w/v). Lower bioleaching performances than this were obtained for a longer HRT of 120 h and a shorter HRT of 40 h. In addition, there was obvious competition between Leptospirillum ferriphilum and Acidithiobacillus ferrooxidans to oxidize ferrous iron, causing large compositional differences between the microbial communities obtained for the different HRTs. Leptospirillum ferriphilum and Acidithiobacillus thiooxidans were found to be the dominant microbes for the longer HRT (120 h). Acidithiobacillus ferrooxidans became the dominant species when the HRT was decreased. The proportion of Acidithiobacillus thiooxidans was comparatively constant in the microbial community throughout the three process stages.

  7. Comparison of microbial communities in three different mine drainages and their bioleaching efficiencies to low grade of chalcopyrite

    Institute of Scientific and Technical Information of China (English)

    YIN Hua-qun; QIU Guan-zhou; WANG Dian-zuo; CAO Lin-hui; DAI Zhi-min; WANG Jie-wei; LIU Xue-duan

    2007-01-01

    Microbial community diversities in the drainage from three mines (Dexing Copper Mine, Qibaoshan Copper Mine and Yaogangxian Tungsten Mine, China) were analyzed using 16S rDNA PCR-RFLP approach. The efficiencies of chalcopyrite bioleaching were compared using enrichment of the three cultures. Phylogenetic analysis indicates that the dominant microorganisms are clustered with the Proteobacteria, the remaining is affiliated with Nitrospira, Acidobacteria and Actinobacteria.At the genus level, Acidithiobacillus is the dominant group in both YTW and QBS samples, while Spingomonas is dominant in YGX sample. Moreover, the principal component analysis (PCA) reveals that QBS and YTW have similar geochemical character and microbial communities. The results also show that pH value and tungsten concentration play a key role in microbial community distribution and relative abundance. The bioleaching efficiency of the enrichment cultures from YTW and QBS is similar. After 15 d,the bioleaching rates of low grade chalcopyrite (0.99%) are both up to 99.5% when using 10 g/L pulp density due to the similar microbial composition of YTW and QBS. Moreover, the leaching efficiencies of enrichment cultures containing multiple bioleaching microorganisms are higher than that of pure culture Acidithiobacillus ferrooxidans.

  8. Surface modifications of chalcopyrite CuInS2 thin films for photochatodes in photoelectrochemical water splitting under sunlight irradiation

    Science.gov (United States)

    Gunawan; Haris, A.; Widiyandari, H.; Septina, W.; Ikeda, S.

    2017-02-01

    Copper chalcopyrite semiconductors include a wide range of compounds that are of interest for photoelectrochemical water splitting which enables them to be used as photochatodes for H2 generation. Among them, CuInS2 is one of the most important materials due to its optimum band gap energy for sunlight absorption. In the present study, we investigated the application of CuInS2 fabricated by electrodeposition as photochatodes for water splitting. Thin film of CuInS2 chalcopyrite was formed on Mo-coated glass substrate by stacked electrodeposition of copper and indium followed by sulfurization under H2S flow. The films worked as a H2 liberation electrode under cathodic polarization from a solution containing Na2SO4 after loading Pt deposits on the film. Introduction of an n-type CdS layer by chemical bath deposition on the CuInS2 surface before the Pt loading resulted appreciable improvements of H2 liberation efficiency and a higher photocurrent onset potential. Moreover, the use of In2S3 layer as an alternative n-type layer to the CdS significantly improved the H2 liberation performance: the CuInS2 film modified with In2S3 and Pt deposits worked as an efficient photocathode for photoelectrochemical water splitting.

  9. Spray Chemical Vapor Deposition of Single-Source Precursors for Chalcopyrite I-III-VI2 Thin-Film Materials

    Science.gov (United States)

    Hepp, Aloysius F.; Banger, Kulbinder K.; Jin, Michael H.-C.; Harris, Jerry D.; McNatt, Jeremiah S.; Dickman, John E.

    2008-01-01

    Thin-film solar cells on flexible, lightweight, space-qualified substrates provide an attractive approach to fabricating solar arrays with high mass-specific power. A polycrystalline chalcopyrite absorber layer is among the new generation of photovoltaic device technologies for thin film solar cells. At NASA Glenn Research Center we have focused on the development of new single-source precursors (SSPs) for deposition of semiconducting chalcopyrite materials onto lightweight, flexible substrates. We describe the syntheses and thermal modulation of SSPs via molecular engineering. Copper indium disulfide and related thin-film materials were deposited via aerosol-assisted chemical vapor deposition using SSPs. Processing and post-processing parameters were varied in order to modify morphology, stoichiometry, crystallography, electrical properties, and optical properties to optimize device quality. Growth at atmospheric pressure in a horizontal hotwall reactor at 395 C yielded the best device films. Placing the susceptor closer to the evaporation zone and flowing a more precursor-rich carrier gas through the reactor yielded shinier-, smoother-, and denser-looking films. Growth of (112)-oriented films yielded more Cu-rich films with fewer secondary phases than growth of (204)/(220)-oriented films. Post-deposition sulfur-vapor annealing enhanced stoichiometry and crystallinity of the films. Photoluminescence studies revealed four major emission bands and a broad band associated with deep defects. The highest device efficiency for an aerosol-assisted chemical vapor deposited cell was one percent.

  10. Draft Genome Sequence of "Acidibacillus ferrooxidans" ITV01, a Novel Acidophilic Firmicute Isolated from a Chalcopyrite Mine Drainage Site in Brazil.

    Science.gov (United States)

    Dall'Agnol, Hivana; Ñancucheo, Ivan; Johnson, D Barrie; Oliveira, Renato; Leite, Laura; Pylro, Victor S; Holanda, Roseanne; Grail, Barry; Carvalho, Nelson; Nunes, Gisele Lopes; Tzotzos, George; Fernandes, Gabriel Rocha; Dutra, Julliane; Orellana, Sara Cuadros; Oliveira, Guilherme

    2016-03-17

    Here, we report the draft genome sequence of "Acidibacillus ferrooxidans" strain ITV01, a ferrous iron- and sulfide-mineral-oxidizing, obligate heterotrophic, and acidophilic bacterium affiliated with the phylum Firmicutes. Strain ITV01 was isolated from neutral drainage from a low-grade chalcopyrite from a mine in northern Brazil.

  11. Draft Genome Sequence of “Acidibacillus ferrooxidans” ITV01, a Novel Acidophilic Firmicute Isolated from a Chalcopyrite Mine Drainage Site in Brazil

    Science.gov (United States)

    Dall’Agnol, Hivana; Ñancucheo, Ivan; Johnson, D. Barrie; Oliveira, Renato; Leite, Laura; Holanda, Roseanne; Grail, Barry; Carvalho, Nelson; Nunes, Gisele Lopes; Tzotzos, George; Fernandes, Gabriel Rocha; Dutra, Julliane; Orellana, Sara Cuadros

    2016-01-01

    Here, we report the draft genome sequence of “Acidibacillus ferrooxidans” strain ITV01, a ferrous iron- and sulfide-mineral-oxidizing, obligate heterotrophic, and acidophilic bacterium affiliated with the phylum Firmicutes. Strain ITV01 was isolated from neutral drainage from a low-grade chalcopyrite from a mine in northern Brazil. PMID:26988062

  12. Analysis of the structural, electronic and optic properties of Ni doped MgSiP2 semiconductor chalcopyrite compound

    Science.gov (United States)

    Kocak, Belgin; Ciftci, Yasemin Oztekin

    2016-03-01

    The structural, electronic band structure and optic properties of the Ni doped MgSiP2 chalcopyrite compound have been performed by using first-principles method in the density functional theory (DFT) as implemented in Vienna Ab-initio Simulation Package (VASP). The generalized gradient approximation (GGA) in the scheme of Perdew, Burke and Ernzerhof (PBE) is used for the exchange and correlation functional. The present lattice constant (a) follows generally the Vegard's law. The electronic band structure, total and partial density of states (DOS and PDOS) are calculated. We present data for the frequency dependence of imaginary and real parts of dielectric functions of Ni doped MgSiP2. For further investigation of the optical properties the reflectivity, refractive index, extinction coefficient and electron energy loss function are also predicted. Our obtained results indicate that the lattice constants, electronic band structure and optical properties of this compound are dependent on the substitution concentration of Ni.

  13. Vibrational and thermal properties of ternary semiconductors and their isotopic dependence: chalcopyrite CuGaS{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, Reinhard K.; Cardona, Manuel; Lauck, Rudolf [MPI fuer Festkoerperforschung, Stuttgart (Germany); Romero, Aldo H. [CINVESTAV, Unidad Queretaro, Queretaro (Mexico); Munoz, Alfonso [MALTA Consolider Team, Dept. de Fisica, Universidad de La Laguna, La Laguna, Tenerife (Spain)

    2011-07-01

    The availability of ab initio electronic calculations and the concomitant techniques for deriving the corresponding lattice dynamics have been profusely used in the past decade for calculating thermodynamic and vibrational properties of semiconductors, as well as their dependence on isotopic masses. The latter have been compared with experimental data for elemental and binary semiconductors with different isotopic compositions. Here we present experimental and theoretical data for several vibronic and thermodynamic properties of a canonical ternary semiconductor of the chalcopyrite family: CuGaS{sub 2}. Among these properties are the lattice parameters, the phonon dispersion relations and densities of states (projected on the Cu, Ga, and S constituents), the specific heat and the volume expansion coefficient. The calculations were performed with the ABINIT and VASP codes within the LDA approximation for exchange and correlation.

  14. Band Gap Energy of Chalcopyrite Thin Film Solar Cell Absorbers Determined by Soft X-Ray Emission and Absorption Spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Bar, M.; Weinhardt, L.; Pookpanratana, S.; Heske, C.; Nishiwaki, S.; Shafarman, W.; Fuchs, O.; Blum, M.; Yang, W.; Denlinger, J.D.

    2008-05-11

    The chemical and electronic structure of high efficiency chalcopyrite thin film solar cell absorbers significantly differs between the surface and the bulk. While it is widely accepted that the absorber surface exhibits a Cu-poor surface phase with increased band gap (Eg), a direct access to the crucial information of the depth-dependency of Eg is still missing. In this paper, we demonstrate that a combination of x-ray emission and absorption spectroscopy allows a determination of Eg in the surface-near bulk and thus complements the established surface- and bulk-sensitive techniques of Eg determination. As an example, we discuss the determination of Eg for a Cu(In,Ga)Se2 absorber [(1.52 +- 0.20) eV].

  15. Structural and elastic properties of defect chalcopyrite HgGa{sub 2}S{sub 4} under high pressure

    Energy Technology Data Exchange (ETDEWEB)

    Gomis, O., E-mail: osgohi@fis.upv.es [Centro de Tecnologías Físicas: Acústica, Materiales y Astrofísica, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); Santamaría-Pérez, D. [Departamento de Física Aplicada-ICMUV, MALTA Consolider Team, Universitat de València, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100 València (Spain); Departamento de Química Física I, Universidad Complutense de Madrid, MALTA Consolider Team, Avenida Complutense s/n, 28040 Madrid (Spain); Vilaplana, R.; Luna, R. [Centro de Tecnologías Físicas: Acústica, Materiales y Astrofísica, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); Sans, J.A.; Manjón, F.J. [Instituto de Diseño para la Fabricación y Producción Automatizada, MALTA Consolider Team, Universitat Politècnica de València, 46022 València (Spain); Errandonea, D. [Departamento de Física Aplicada-ICMUV, MALTA Consolider Team, Universitat de València, Edificio de Investigación, C/Dr. Moliner 50, Burjassot, 46100 València (Spain); and others

    2014-01-15

    Highlights: • Single crystals of HgGa{sub 2}S{sub 4} with defect-chalcopyrite (DC) structure were synthesized. • High-pressure X-ray diffraction in DC-HgGa{sub 2}S{sub 4} was performed. • Equation of state of DC-HgGa{sub 2}S{sub 4} determined (bulk modulus of 48.4 GPa). • Calculated elastic constants of DC-HgGa{sub 2}S{sub 4} reported at different pressures. • DC-HgGa{sub 2}S{sub 4} becomes mechanically unstable above 13.8 GPa. -- Abstract: In this work, we focus on the study of the structural and elastic properties of mercury digallium sulfide (HgGa{sub 2}S{sub 4}) at high pressures. This compound belongs to the family of AB{sub 2}X{sub 4} ordered-vacancy compounds and exhibits a tetragonal defect chalcopyrite structure. X-ray diffraction measurements at room temperature have been performed under compression up to 15.1 GPa in a diamond anvil cell. Our measurements have been complemented and compared with ab initio total energy calculations. The axial compressibility and the equation of state of the low-pressure phase of HgGa{sub 2}S{sub 4} have been experimentally and theoretically determined and compared to other related ordered-vacancy compounds. The pressure dependence of the theoretical cation–anion and vacancy-anion distances and compressibilities in HgGa{sub 2}S{sub 4} are reported and discussed in comparison to other related ordered-vacancy compounds. Finally, the pressure dependence of the theoretical elastic constants and elastic moduli of HgGa{sub 2}S{sub 4} has been studied. Our calculations indicate that the low-pressure phase of HgGa{sub 2}S{sub 4} becomes mechanically unstable above 13.8 GPa.

  16. Rapid thermal processing for production of chalcopyrite thin films for solar cells: Design, analysis, and experimental implementation

    Science.gov (United States)

    Lovelett, Robert J.

    The direct conversion of solar energy to electricity, or photovoltaic energy conversion, has a number of environmental, social, and economic advantages over conventional electricity generation from fossil fuels. Currently, the most commonly-used material for photovoltaics is crystalline silicon, which is now produced at large scale and silicon-based devices have achieved power conversion efficiencies over 25% However, alternative materials, such as inorganic thin films, offer a number of advantages including the potential for lower manufacturing costs, higher theoretical efficiencies, and better performance in the field. One of these materials is the chalcopyrite Cu(InGa)(SeS) 2, which has demonstrated module efficiencies over 17% and cell efficiencies over 22%. Cu(InGa)(SeS)2 is now in the early stages of commercialization using a precursor reaction process referred to as a "selenization/sulfization" reaction. The precursor reaction process is promising because it has demonstrated high efficiency along with the large area (approximately 1 m2) uniformity that is required for modules. However, some challenges remain that limit the growth of the chalcopyrite solar cell industry including: slow reactions that limit process throughput, a limited understanding of complex reaction kinetics and transport phenomena that affect the through-film composition, and the use of highly toxic H2Se in the reaction process. In this work, I approach each of these challenges. First, to improve process throughput, I designed and implemented a rapid thermal processing (RTP) reactor, whereby the samples are heated by a 1000 W quartz-halogen lamp that is capable of fast temperature ramps and high temperature dwells. With the reactor in place, however, achieving effective temperature control in the thin film material system is complicated by two intrinsic process characteristics: (i) the temperature of the Cu(InGa)(SeS)2 film cannot be measured directly, which leaves the system without

  17. Electronic structure of epitaxial chalcopyrite surfaces and interfaces for photovoltaics; Elektronische Struktur epitaktischer Chalkopyrite und deren Heterokontakte fuer die Photovoltaik

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, Andreas

    2012-02-14

    This thesis constitutes a comprehensive study of the surface physics of epitaxial CuInSe{sub 2} films. It comprises analyses of the surface morphology and reconstruction, electronic band structure as well as hetero-junctions relevant to photovoltaic applications. Therefore, especially the aspect of stoichiometry variation from the CuInSe{sub 2} to the copper-deficient defect phases was considered. Preparation and analysis was completely performed under ultra-high vacuum conditions in order to ensure the investigation of well-defined samples free of contaminants. For some of the analysis techniques, single-crystalline samples are indispensable: They allow for the determination of surface periodicity by low-energy electron diffraction (LEED). In combination with concentration depth profiling by angle-resolved x-ray photoemission, to types of surface reconstructions could be distinguished for the near-stoichiometric CuInSe{sub 2}(112) surface. In the copper-rich case, it is stabilized by Cu{sub In} anti-site defects and on the indium-rich side by 2 V{sub Cu} defects, as predicted by surface total energy calculations by Jaffe and Zunger. Both configurations correspond to a c(4 x 2) reconstruction of the zinc blende type (111) surface. For the defect compound CuIn{sub 3}Se{sub 5}, a sphalerite order of the surface was found, which points at a weakening or absence of the chalcopyrite order in the bulk of the material. The unusual stability of the (112) surface could also be proven by comparison with the reconstruction and surface order of (001) and (220) surfaces. The results from surface analysis were used to measure the valence band structure of the epitaxial samples by synchrotron-based angle-resolved photoelectron spectroscopy. The CuInSe{sub 2}(001) surface gives access to the high symmetry directions {Gamma}-T and {Gamma}-N of momentum space. By contrasting the data obtained for the stoichiometric surface with the copper-poor defect compound, a reduction of the

  18. Defect chalcopyrite Cu(In{sub 1-x}Ga{sub x}){sub 3}Se{sub 5} (0

    Energy Technology Data Exchange (ETDEWEB)

    Contreras, M.A.; Wiesner, H.; Niles, D.; Ramanathan, K.; Matson, R. [National Renewable Energy Lab., Golden, CO (United States)] [and others

    1996-05-01

    Crystallographic, optical, and electrical properties of defect chalcopyrite Cu(In{sub 1{minus}x}Ga{sub x}){sub 3}Se{sub 5} (0chalcopyrite CuIn{sub 1 {minus}x}Ga{sub x}Se{sub 2} absorber materials is presented. Considering the chalcopyrite/defect chalcopyrite junction model, the authors postulate that the traditionally poor device performance of uniform high-Ga-content absorbers (x>0.3) is due to a relatively inferior character - both structural and electrical - at the very chalcopyrite/defect chalcopyrite interface. They demonstrate that this situation can be circumvented (for absorbers with x>0.3) by properly engineering such an interface by reducing Ga content in the region near the surface of the absorber.

  19. Attachment of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum cultured under varying conditions to pyrite, chalcopyrite, low-grade ore and quartz in a packed column reactor.

    Science.gov (United States)

    Africa, Cindy-Jade; van Hille, Robert P; Harrison, Susan T L

    2013-02-01

    The attachment of Acidithiobacillus ferrooxidans and Leptospirillum ferriphilum spp. grown on ferrous medium or adapted to a pyrite mineral concentrate to four mineral substrata, namely, chalcopyrite and pyrite concentrates, a low-grade chalcopyrite ore (0.5 wt%) and quartzite, was investigated. The quartzite represented a typical gangue mineral and served as a control. The attachment studies were carried out in a novel particle-coated column reactor. The saturated reactor containing glass beads, which were coated with fine mineral concentrates, provided a quantifiable surface area of mineral concentrate and maintained good fluid flow. A. ferrooxidans and Leptospirillum spp. had similar attachment characteristics. Enhanced attachment efficiency occurred with bacteria grown on sulphide minerals relative to those grown on ferrous sulphate in an ore-free environment. Selective attachment to sulphide minerals relative to gangue materials occurred, with mineral adapted cultures attaching to the minerals more efficiently than ferrous grown cultures. Mineral-adapted cultures showed highest levels of attachment to pyrite (74% and 79% attachment for A. ferrooxidans and L. ferriphilum, respectively). This was followed by attachment of mineral-adapted cultures to chalcopyrite (63% and 58% for A. ferrooxidans and L. ferriphilum, respectively). A. ferrooxidans and L. ferriphilum exhibited lower levels of attachment to low-grade ore and quartz relative to the sulphide minerals.

  20. Effect of Na substitution on electronic and optical properties of CuInS{sub 2} chalcopyrite semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, S.; Ganguli, B., E-mail: biplabg@nitrkl.ac.in

    2015-12-15

    Electronic & optical properties of Na substituted CuNaIn{sub 2}S{sub 4} chalcopyrite semiconductors are significantly modified due to Na substitution in the Cu deficient CuInS{sub 2} semiconductor. These properties are obtained form first principle calculation using density functional theory based tight binding Linear muffin tin orbital method. The presence of Na alters the structural distortion and enhances strengths of Cu d and S p hybridization in CuNaIn{sub 2}S{sub 4}. This effect reduces band gap, in agreement with experimental observations and modify other properties significantly. Calculations of optical matrix elements (OME) and joint density of states (JDOS) show that effects of Na substitution on optical properties come through p–d hybridization and structural distortion. OME contribution is prominent near band edge. Both systems show anisotropic optical properties. - Graphical abstract: The figure shows the band structure and total density of states of CuNaIn{sub 2}S{sub 4}. It illustrates energy bands at various symmetry points, band gap and contribution of various orbitals.

  1. 磷灰石在微生物浸铜体系的溶出特性及对浸铜效率的影响%Dissolution characteristics of apatite in chalcopyrite bioleaching system and its influence on chalcopyrite leaching efficiency

    Institute of Scientific and Technical Information of China (English)

    周闪闪; 林海; 董颖博; 许晓芳

    2014-01-01

    To make sure the dissolution characteristics of apatite in the chalcopyrite bioleaching system and the influence on the chalcopyrite leaching efficiency, the apatite with particle size of less than 43 μm, chalcopyrite with 74 μm and Acidithiobacillus ferrooxidans (At.f) were used to prepare a bioleaching system. And the influence of different At.f inoculation amount on the apatite dissolution rate and chalcopyrite leaching effect were studied. The results show that chalcopyrite leaching efficiency can be improved when there exists PO 4 3− with low concentration in the bioleaching system. And PO43− reaches the lowest concentration of 0.62 mg/L in the bioleaching system when the At.f inoculation amount is 5%, and the final chalcopyrite leaching rate reaches the highest of 57.4%, which is 30%higher than that in the bioleaching system with the highest concentration of PO43−. Scanning electron microscope (SEM), energy dispersive spectroscope and X-ray diffraction (XRD) analyses before and after the bioleaching show that, there is not any obvious erosion on the apatite surface after leaching, while obvious erosion exists on the chalcopyrite surface and new compound ammoniojarosite generates in the leaching residue. And the precipitates newly generated can be absorbed by apatite, low concentration PO 4 3−in the bioleaching system can improve the leaching of chalcopyrite.%为了探明磷灰石在微生物浸出黄铜矿体系中的溶出特性及其对黄铜矿浸出的影响,选择粒径小于43μm的磷灰石与粒径小于74μm的黄铜矿以及At.f菌组成矿浆浸出体系,考察不同At.f菌接种量对于磷灰石溶出速率的影响及对黄铜矿浸出效果的影响。结果表明:浸出体系中含低浓度PO 43−可以提高铜的浸出效率;当At.f菌接种量为5%时,微生物浸出体系中磷灰石溶出的PO 43−浓度最小,为0.62 mg/L,此时黄铜矿的最终浸出率最高,达到57.4%,比PO 43−溶液浓度最高时

  2. A Study of the Effect of Djurliete, Bornite and Chalcopyrite during the Dissolution of Gold with a Solution of Ammonia-Cyanide

    Directory of Open Access Journals (Sweden)

    Mike Fulton

    2012-11-01

    Full Text Available The high solubility of copper sulphide minerals is an issue in the cyanidation of gold ores. The objective of this study was to quantify the effect of individual copper sulphide minerals on the Hunt process, which showed advantages over cyanidation. High purity djurleite, bornite and chalcopyrite, with a P70 of 70–74 microns, were mixed with fine quartz and gold powder (3–8 micron to obtain a copper concentration of 0.3%. The ammonia-cyanide leaching of slurry with djurleite proved to be more effective than cyanidation; producing comparable extraction of gold (99%, while reducing the cyanide consumption from 5.8 to 1.2 kg/t NaCN. Lead nitrate improved the Hunt leaching. The lower cyanide consumption is associated to a significant reduction of copper dissolved. XPS surface analysis of djurleite showed that lead nitrate favored the formation of Cu(OH2 species. Lead was also detected on the surface (oxide or hydroxide. Sulphide and copper compounds (cyanide and sulphide were reaction products responsible for inhibiting the dissolution of gold. Lead nitrate added in the Hunt leaching of bornite produced 99% gold extraction. Surface reaction products were similar to djurleite. The cyanide consumption (~4.4 kg/t NaCN was not reduced by the addition of ammonia. Cyanidation of chalcopyrite showed a lower consumption of cyanide 0.33 kg/t NaCN compared to 0.21 kg/t NaCN for Hunt. No significant interferences were observed in gold leaching with a slurry containing chalcopyrite.

  3. FP-LAPW investigation of structural, electronic, linear and nonlinear optical properties of ZnIn2Te4 defect-chalcopyrite

    OpenAIRE

    AYEB, Y.; OUAHRANI, T.; Khenata, R.; Reshak, Ali H.; RACHED, D.; Bouhemadou, A.; ARRAR, R.

    2010-01-01

    A theoretical study of structural, electronic, linear and nonlinear optical properties of ZnIn2Te4 defect-chalcopyrite is presented using the full-potential linearized augmented plane-wave (FP-LAPW) method. The exchange and correlation potential is treated by the generalized-gradient approximation (GGA). Moreover, the Engel and Vosko GGA formalism (EV-GGA) is also used to improve the band gap results. The lattice parameters (a, c) and the atomic positions (x, y and z) are optimized and found ...

  4. Optimization of staged bioleaching of low-grade chalcopyrite ore in the presence and absence of chloride in the irrigating lixiviant: ANFIS simulation.

    Science.gov (United States)

    Vakylabad, Ali Behrad; Schaffie, Mahin; Naseri, Ali; Ranjbar, Mohammad; Manafi, Zahra

    2016-07-01

    In this investigation, copper was bioleached from a low-grade chalcopyrite ore using a chloride-containing lixiviant. In this regard, firstly, the composition of the bacterial culture media was designed to control the cost in commercial application. The bacterial culture used in this process was acclimated to the presence of chloride in the lixiviant. Practically speaking, the modified culture helped the bio-heap-leaching system operate in the chloridic media. Compared to the copper recovery from the low-grade chalcopyrite by bioleaching in the absence of chloride, bioleaching in the presence of chloride resulted in improved copper recovery. The composition of the lixiviant used in this study was a modification with respect to the basal salts in 9 K medium to optimize the leaching process. When leaching the ore in columns, 76.81 % Cu (based on solid residues of bioleaching operation) was recovered by staged leaching with lixiviant containing 34.22 mM NaCl. The quantitative findings were supported by SEM/EDS observations, X-ray elemental mapping, and mineralogical analysis of the ore before and after leaching. Finally, Adaptive neuro-fuzzy inference system (ANFIS) was used to simulate the operational parameters affecting the bioleaching operation in chloride-sulfate system.

  5. Enhanced thermoelectric performance of a chalcopyrite compound CuIn3Se5-xTex (x = 0~0.5) through crystal structure engineering

    Science.gov (United States)

    Lu, Yufu; Chen, Shaoping; Wu, Wenchang; Du, Zhengliang; Chao, Yimin; Cui, Jiaolin

    2017-01-01

    In this work the chalcopyrite CuIn3Se5-xTex (x = 0~0.5) with space group through isoelectronic substitution of Te for Se have been prepared, and the crystal structure dilation has been observed with increasing Te content. This substitution allows the anion position displacement ∆u = 0.25-u to be zero at x ≈ 0.15. However, the material at x = 0.1 (∆u = 0.15 × 10-3), which is the critical Te content, presents the best thermoelectric (TE) performance with dimensionless figure of merit ZT = 0.4 at 930 K. As x value increases from 0.1, the quality factor B, which informs about how large a ZT can be expected for any given material, decreases, and the TE performance degrades gradually due to the reduction in nH and enhancement in κL. Combining with the ZTs from several chalcopyrite compounds, it is believable that the best thermoelectric performance can be achieved at a certain ∆u value (∆u ≠ 0) for a specific space group if their crystal structures can be engineered.

  6. Enhanced thermoelectric performance of a chalcopyrite compound CuIn3Se5−xTex (x = 0~0.5) through crystal structure engineering

    Science.gov (United States)

    Lu, Yufu; Chen, Shaoping; Wu, Wenchang; Du, Zhengliang; Chao, Yimin; Cui, Jiaolin

    2017-01-01

    In this work the chalcopyrite CuIn3Se5−xTex (x = 0~0.5) with space group through isoelectronic substitution of Te for Se have been prepared, and the crystal structure dilation has been observed with increasing Te content. This substitution allows the anion position displacement ∆u = 0.25-u to be zero at x ≈ 0.15. However, the material at x = 0.1 (∆u = 0.15 × 10−3), which is the critical Te content, presents the best thermoelectric (TE) performance with dimensionless figure of merit ZT = 0.4 at 930 K. As x value increases from 0.1, the quality factor B, which informs about how large a ZT can be expected for any given material, decreases, and the TE performance degrades gradually due to the reduction in nH and enhancement in κL. Combining with the ZTs from several chalcopyrite compounds, it is believable that the best thermoelectric performance can be achieved at a certain ∆u value (∆u ≠ 0) for a specific space group if their crystal structures can be engineered. PMID:28057940

  7. Influence factors of pyrite promotion on the bioleaching of chalcopyrite%黄铁矿促进黄铜矿微生物浸出影响因素

    Institute of Scientific and Technical Information of China (English)

    莫晓兰; 林海; 傅开彬; 徐承焱; 汪涵

    2012-01-01

    Chalcopyrite-pyrite bioleaching tests were performed with shaking flasks by Aeidithiobacillusferrooxidans. The research focused on the effects of basic salt mediums, pyrite-to-chalcopyrite mass ratio and mineral size distribution. It is found that chaleopyrite bioleaching can be promoted by pyrite, The leaching rate of copper in the iron-free 9K medium in pyrite-chaleopyrite bioleaching is 1.68 times as large as that in the 9K medium. The leaching of copper is better using a wide size range of minerals and the leaching rate of copper is related to the mass ratio of pyrite to chalcopyrite. When the mass ratio is 2: 2, the highest leaching rate of copper is ob- tained to be 45.58%. The content of pyrite is of the essence in affecting the leaching rate level of copper. At a mass ratio of pyrite to chalcopyrite no more than 5:2 the oxidation of Acidithiobacillus ferrooxidans plays an important role in the bioleaching, but when the mass ratio is 10:2 the galvanic effect between the two sulphide minerals mainly influences the bioleaehing. X-ray diffraction analyses of leaching residues indicate that the generation of jarosite in the iron-free 9K medium is less than that in the 9K medium, FeSO4 in the 9K medium can be replaced by pyrite, the galvanic effect forms with chaleopyrite, and therefore the bioleaehing efficiency of copper is increased.%采用摇瓶实验,以氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,At.f)浸出黄铁矿--黄铜矿,重点研究了基础培养基、矿物配比和粒度组成等因素的影响.黄铁矿能促进黄铜矿的微生物浸出,以采用无Fe 9K培养基效果较好,它对应铜浸出率是9K培养基的1.68倍;采用宽粒级矿物时铜浸出效果较好,且铜浸出率与黄铁矿和黄铜矿的质量比有关,当质量比为2∶2时铜浸出率最高可达45.58%;黄铁矿含量大小是影响铜浸出率高低的实质,当质量比小于等于5∶2时以At.f菌的氧化作用为主,当质量比为10∶2时以硫

  8. First and second harmonic generation of the XAl{sub 2}Se{sub 4} (X=Zn,Cd,Hg) defect chalcopyrite compounds

    Energy Technology Data Exchange (ETDEWEB)

    Ouahrani, Tarik, E-mail: tarik_ouahrani@yahoo.fr [Laboratoire de Physique Theorique, Universite de Tlemcen, B.P.230,13000 Tlemcen (Algeria); Ecole Preparatoire en Sciences et Techniques, Depertement de Physique EPST-T, Tlemcen 13000 (Algeria); Khenata, R. [Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Universite de Mascara, 29000 Mascara (Algeria); Lasri, B. [Laboratoire de Physique Theorique, Universite de Tlemcen, B.P.230,13000 Tlemcen (Algeria); Universite Dr Tahar Moulay de Saida, B.P. 138, Cite el Nasr, Saida 20000 (Algeria); Reshak, Ali H. [School of Complex systems, FFPW- South Bohemia University, Nove Hrady 37333 (Czech Republic); School of Material Engineering, Malaysia University of Perlis, P.O Box 77, d/a Pejabat Pos Besar, 01007 Kangar, Perlis (Malaysia); Bouhemadou, A. [Department of Physics, Faculty of Sciences, University of Setif, 19000 Setif (Algeria); Bin-Omran, S. [Department of Physics and Astronomy, Faculty of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia)

    2012-09-15

    The chemical bonding of the ZnAl{sub 2}Se{sub 4}, CdAl{sub 2}Se{sub 4} and HgAl{sub 2}Se{sub 4} defect chalcopyrites has been studied in the framework of the quantum theory of atoms in molecules (AIM). The GW quasi-particle approximation is used to correct the DFT-underestimation of energy gap, and as a consequence the linear and nonlinear optical properties are significantly enhanced. The second harmonic generation (SHG) displays certain dependence with the ionicity degree decrease through the dependency of the SHG on the band gap. The occurrence of the AIM saddle point is characterized and some clarifying features in relationship with the density topology are exposed, which enable to understand the relation with the second harmonic generation effect.

  9. Surface species of chalcopyrite during bioleaching by moderately thermophilic bacteria%中度嗜热菌浸出黄铜矿过程表面产物解析

    Institute of Scientific and Technical Information of China (English)

    赵红波; 王军; 覃文庆; 郑细华; 陶浪; 甘晓文; 邱冠周

    2015-01-01

    采用X射线衍射(XRD)与X射线光电子能谱(XPS)研究黄铜矿在中度嗜热菌浸出过程中的表面产物变化。结果表明,在A. caldus,S. thermosulfidooxidans与L. ferriphilum浸出过程中,一硫化物(CuS)、二硫化物(S22−)、元素硫(S0)、多硫化物(Sn2−)与硫酸盐(SO42−)是黄铜矿表面的主要产物。在A. caldus浸出黄铜矿过程速率较慢,这主要是由于黄铜矿的不完全溶解产生多硫化物,限制了进一步的溶解。在S. thermosulfidooxidans与L. ferriphilum浸出黄铜矿过程中,多硫化物与黄钾铁矾是钝化膜的主要成分。元素硫不是导致黄铜矿生物冶金过程钝化的主要物质。%X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS) analyses were carried out to investigate the surface species and interfacial reactions during bioleaching of chalcopyrite by different strains of moderately thermophilic bacteria (45 °C). Results show that monosulfide (CuS), disulfide (S22−), polysulfide (Sn2−), elemental sulfur (S0) and sulfate (SO42−) are the main intermediate species on the surface of chalcopyrite during bioleaching byA. caldus,S. thermosulfidooxidans andL. ferriphilum. The low kinetics of dissolution of chalcopyrite inA. caldus can be mainly attributed to the incomplete dissolution of chalcopyrite and the passivation layer of polysulfide. Polysulfide and jarosite should be mainly responsible for the passivation of chalcopyrite in bioleaching byL. ferriphilumorS. thermosulfidooxidans. However, elemental sulfur should not be the main composition of passivation layer of chalcopyrite during bioleaching.

  10. An electrochemical study of the oxidation of chalcopyrite in acidic mediums with ferric iron (Fe3+)%黄铜矿在含铁酸性介质中氧化过程的电化学研究

    Institute of Scientific and Technical Information of China (English)

    赵晋宁; 易筱筠; 党志

    2013-01-01

    以天然黄铜矿为研究对象,运用开路电位,循环伏安曲线,Tafel极化曲线和交流阻抗(EIS)等电化学手段,对在硫酸介质中三价铁离子对黄铜矿的氧化过程的电化学行为进行了研究.结果表明,黄铜矿在酸性介质中的氧化可能通过两步反应完成,第一步中电极表面形成了一层主要成分是含硫中间产物的钝化膜,第二步则是黄铜矿主体的氧化.Fe3+离子有助于黄铁矿的直接氧化,在黄铜矿的溶解过程中起到了重要作用.极化曲线测量的结果显示随着溶液中Fe3+离子浓度的增加,黄铜矿的极化电流也在增加,黄铜矿也更容易进入钝化阶段.同时,交流阻抗对Fe3+离子浓度改变的响应也很敏感.%The electrochemical behavior of the effect of ferric iron ( Fe3+ ) on the solution of chalcopyrite was investigated using electrochemical techniques including measurements of open circuit potential, cyclic voltammetry, Tafel polarization curves and electrochemical impedance spectroscopy (EIS). The results show that the chalcopyrite oxidation process in acidic mediums takes place via a two - step reaction. A passivation film composed of intermediate product mixed with sulfur is formed during the first step, and the bulk of chalcopyrite is oxidized in the second step. Ferric iron plays an important role in the dissolution of chalcopyrite by enhancing the direct oxidation. The Tafel polarization curves indicate that the polarization current of the chalcopyrite electrode increases with an increase of Fe3+ concentration. It has also been shown that the higher concentration of Fe 3+ is, the more easily the chalcopyrite can be transformed into the passivation region. In addition, the EIS response is found to be sensitive to changes in Fe3+ concentration.

  11. Influence of temperature on the fixation and penetration of silver during the chalcopyrite leaching using moderate thermophilic microorganisms; Influencia de la temperatura en la fijacion y penetracion de la plata durante la lixiviacion de calcopirita con microorganismos termofilos moderados

    Energy Technology Data Exchange (ETDEWEB)

    Cancho, L.; Blazquez, M. L.; Munoz, J. A.; Gonzalez, F.; Ballester, A.

    2004-07-01

    Bio leaching of chalcopyrite using mesophilic microorganisms considerable improves in the presence of silver. However, the studies carried out with moderate thermophilic microorganisms do not show a significant improvement with regard to the use of mesophilic bacteria. The main objective of the present work has been to study the silver fixation on chalcopyrite ar 35 and 45 degree centigree and its influence on the microbiological attack. Different observations using SEM, EDS microanalysis and concentration profiles using electron microprobe have been carried out. The study of the different samples showed that silver fixation was more favourable at 35 degree centigree than at 45 degree centigree. In addition, bacterial action improved silver penetration through attack cracks. (Author)

  12. Optimization of Electrochemically Deposited Highly Doped ZnO Bilayers on Ga-Rich Chalcopyrite Selenide for Cost-Effective Photovoltaic Device Technology

    Directory of Open Access Journals (Sweden)

    Dimitra N. Papadimitriou

    2016-11-01

    Full Text Available High quality polycrystalline bilayers of aluminium doped ZnO (Al:ZnO were successively electrodeposited in the form of columnar structures preferentially oriented along the ( 10 1 ¯ 1 crystallographic direction from aqueous solution of zinc nitrate (Zn(NO32 at negative electrochemical potential of EC = (−0.8–(−1.2 V and moderate temperature of 80 °C on gallium rich (30% Ga chalcopyrite selenide Cu(In,GaSe2 (CIGS with chemically deposited ZnSe buffer (ZnSe/Cu(In,GaSe2/Mo/glass. The aluminium doped ZnO layer properties have initially been probed by deposition of Al:ZnO/i-ZnO bilayers directly on Mo/glass substrates. The band-gap energy of the Al:ZnO/i-ZnO reference layers was found to vary from 3.2 to 3.7 eV by varying the AlCl3 solute dopant concentration from 1 to 20 mM. The electrical resistivity of indium-pellet contacted highly doped Al:ZnO sheet of In/Al:ZnO/i-ZnO/Mo/glass reference samples was of the order ρ ~10−5 Ω·cm; the respective carrier concentration of the order 1022 cm−3 is commensurate with that of sputtered Al:ZnO layers. For crystal quality optimization of the bilayers by maintenance of the volatile selenium content of the chalcopyrite, they were subjected to 2-step annealing under successive temperature raise and N2 flux regulation. The hydrostatic compressive strain due to Al3+ incorporation in the ZnO lattice of bilayers processed successively with 5 and 12 mM AlCl3 dopant was εh = −0.046 and the respective stress σh = −20 GPa. The surface reflectivity of maximum 5% over the scanned region of 180–900 nm and the (optical band gap of Eg = 3.67 eV were indicative of the high optical quality of the electrochemically deposited (ECD Al:ZnO bilayers.

  13. X-ray photoelectron spectrum and electronic properties of a noncentrosymmetric chalcopyrite compound HgGa(2)S(4): LDA, GGA, and EV-GGA.

    Science.gov (United States)

    Reshak, Ali Hussain; Khenata, R; Kityk, I V; Plucinski, K J; Auluck, S

    2009-04-30

    An all electron full potential linearized augmented plane wave method has been applied for a theoretical study of the band structure, density of states, and electron charge density of a noncentrosymmetric chalcopyrite compound HgGa(2)S(4) using three different approximations for the exchange correlation potential. Our calculations show that the valence band maximum (VBM) and conduction band minimum (CBM) are located at Gamma resulting in a direct energy gap of about 2.0, 2.2, and 2.8 eV for local density approximation (LDA), generalized gradient approximation (GGA), and Engel-Vosko (EVGGA) compared to the experimental value of 2.84 eV. We notice that EVGGA shows excellent agreement with the experimental data. This agreement is attributed to the fact that the Engel-Vosko GGA formalism optimizes the corresponding potential for band structure calculations. We make a detailed comparison of the density of states deduced from the X-ray photoelectron spectra with our calculations. We find that there is a strong covalent bond between the Hg and S atoms and Ga and S atoms. The Hg-Hg, Ga-Ga, and S-S bonds are found to be weaker than the Hg-S and Ga-S bonds showing that a covalent bond exists between Hg and S atoms and Ga and S atoms.

  14. Lattice defects and thermoelectric properties: the case of p-type CuInTe2 chalcopyrite on introduction of zinc.

    Science.gov (United States)

    Yang, Jiangfeng; Chen, Shaoping; Du, Zhengliang; Liu, Xianglian; Cui, Jiaolin

    2014-10-28

    I-III-VI2 chalcopyrites have unique inherent crystal structure defects, and hence are potential candidates for thermoelectric materials. Here, we identified mixed polyanionic/polycationic site defects (ZnIn(-), VCu(-), InCu(2+) and/or ZnCu(+)) upon Zn substitution for either Cu or In or both in CuInTe2, with the ZnIn(-) species originating from the preference of Zn for the cation 4b site. Because of the mutual reactions among these charged defects, Zn substitution in CuInTe2 alters the basic conducting mechanism, and simultaneously changes the lattice structure. The alteration of the lattice structure can be embodied in an increased anion position displacement (u) or a reduced bond length difference (Δd) between d(Cu-Te)4a and d(In-Te)4b with increasing Zn content. Because of this, the lattice distortion is diminished and the lattice thermal conductivity (κL) is enhanced. The material with simultaneous Zn substitution for both Cu and In had a low κL, thereby we attained the highest ZT value of 0.69 at 737 K, which is 1.65 times that of Zn-free CuInTe2.

  15. Structural, elastic, electronic, bonding, and optical properties of BeAZ{sub 2} (A = Si, Ge, Sn; Z = P, As) chalcopyrites

    Energy Technology Data Exchange (ETDEWEB)

    Fahad, Shah [Department of Physics, Hazara University Mansehra, KPK, Mansehra (Pakistan); Murtaza, G., E-mail: murtaza@icp.edu.pk [Materials Modeling Laboratory, Department of Physics, Islamia College University, Peshawar (Pakistan); Ouahrani, T. [Laboratoire de Physique Théorique, B.P. 230, Université de Tlemcen, Tlemcen 13000 (Algeria); Ecole Préparatoire en Sciences et Techniques, BP 165 R.P., 13000 Tlemcen (Algeria); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique et de Modélisation Mathématique, Université de Mascara, 29000 (Algeria); Yousaf, Masood [Center for Multidimensional Carbon Materials, Institute for Basic Science, Department of Physics, Ulsan National Institute of Science and Technology, Ulsan 689-798 (Korea, Republic of); Omran, S.Bin [Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia); Mohammad, Saleh [Department of Physics, Hazara University Mansehra, KPK, Mansehra (Pakistan)

    2015-10-15

    A first principles density functional theory (DFT) technique is used to study the structural, chemical bonding, electronic and optical properties of BeAZ{sub 2} (A = Si, Ge, Sn; Z = P, As) chalcopyrite materials. The calculated parameters are in good agreement with the available experimental results. The lattice constants and the equilibrium volume increased as we moved from Si to Ge to Sn, whereas the c/a and internal parameters u decreased by shifting the cation from P to As. These compounds are elastically stable. An investigation of the band gap using the WC-GGA, EV-GGA, PBE-GGA and mBJ-metaGGA potentials suggested that BeSiP{sub 2} and BeSiAs{sub 2} are direct band gap compounds, whereas BeGeP{sub 2,} BeGeAs{sub 2,} BeSnP{sub 2,} BeSnAs{sub 2} are indirect band gap compounds. The energy band gaps decreased by changing B from Si to Sn and increased by changing the anion C from P to As. The bonding among the cations and anions is primarily ionic. In the optical properties, the real and imaginary parts of the dielectric functions, reflectivity and optical conductivity have been studied over a wide energy range. - Highlights: • The compounds are studied by FP-LAPW method within mBJ approximation. • All of the studied materials show isotropic behaviour. • All the compounds show direct band gap nature. • Bonding nature is mostly covalent among the studied compounds. • High absorption peaks and reflectivity ensures there utility in optoelectronic devices.

  16. Electronic structure of semiconductor thin films (chalcopyrites) as absorbermaterials for thin film solar cells; Elektronische Struktur duenner Halbleiterfilme (Chalkopyrite) als Absorbermaterialien fuer Duennschichtsolarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, Carsten

    2007-12-11

    The objective of this work was to determine for the first time the band structure of CuInS{sub 2}. For this purpose a new GSMBE process with TBDS as sulphur precursor was established to prevent the use of elemental sulphur in an UHV system. Additionally to the deposited films a cleave surface was prepared. The samples were characterized in situ by XPS/UPS and LEED. XRD and SEM were used for further ex situ investigations. The band structure was determined by ARUPS using synchrotron light. CuInS(001) and CuInS{sub 2}(112) were deposited on Si and GaAs. The deposition of CuInS{sub 2} on GaAs showed a strong dependence on the existing surface reconstruction. A 2 x 1 reconstruction of GaAs(001) yielded CuInS{sub 2}(001) films featuring terraces. A deposition on 2 x 2 reconstructed GaAs(111)A surfaces led to a facetted CuInS{sub 2} surface. On sulphur-passivated non-reconstructed GaAs(111)B a deposition of chalcopyrite ordered CuInS{sub 2} free of facets was possible. On the surface of Cu-rich CuInS{sub 2} films CuS crystallites formed. This yields ARUPS spectra showing the electronic stucture of CuInS{sub 2} superimposed by non-dispergative states of the polycrystalline CuS segregations. The effective hole masses were derived from the k {sub vertical} {sub stroke} {sub vertical} {sub stroke} measurements. Finally the results of this work showed that the use of a (111) substrate leads to domain formation of the deposited CuInS{sub 2}(112) films. Thus ARUPS spectra of such films show a superposition of the band structures along different directions. (orig.)

  17. Effect of p–d hybridization, structural distortion and cation electronegativity on electronic properties of ZnSnX{sub 2} (X=P, As, Sb) chalcopyrite semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Mishra, S. [National Institute of Technology, Rourkela 769008, Odisha (India); Ganguli, B., E-mail: biplabg@nitrkl.ac.in [National Institute of Technology, Rourkela 769008, Odisha (India)

    2013-04-15

    Significant effects of p–d hybridization, structural distortion and cation-electro-negativity are found on band gap in ZnSnX{sub 2} (X=P, As, Sb). Our study suggests these compounds to be direct band gap semiconductors with band gaps of 1.23, 0.68 and 0.19 eV respectively. Lattice constants, tetragonal distortion (η), anion displacement, bond lengths and bulk moduli are calculated by Density Functional Theory based on Tight binding Linear Muffin-Tin orbital method. Our result of structural properties is in good agreement with the available experimental and other theoretical results. Calculated band gaps also agree well with the experimental works within LDA limitation. Unlike other semiconductors in the group II–IV–V{sub 2}, there is a reduction in the band gap of 0.22, 0.20 and 0.24 eV respectively in ZnSnX{sub 2} (X=P, As, Sb) due to p–d hybridization. Structural distortion decreases band gap by 0.20, 0.12 and 0.10 eV respectively. We find that cation electronegativity effect is responsible for increasing the band gap relative to their binary analogs GaInP{sub 2}, InGaAs{sub 2} and GaInSb{sub 2} respectively and increment are 0.13, 0.04 and 0.13 eV respectively. - Graphical abstract: One unit cell of ZnSnX{sub 2} (X=P, As, Sb) chalcopyrite semiconductor. Semiconductors ZnSnX{sub 2} (X=P, As, Sb) are found to be direct band gap semiconductors with band gaps 1.23, 0.68 and 0.19 eV respectively. The quantitative estimate of effects of p–d hybridization, structural distortion and cation electronegativity shows band gaps change significantly due to these effects. Highlights: ► ZnSnX{sub 2} (X=P, As, Sb) are direct band gap semiconductors. ► These have band gaps of 1.23 eV, 0.68 eV and 0.19 eV respectively. ► The band gap reduction due to p–d hybridization is 13.41%, 18.51% and 40% respectively. ► Band gap reduction due to structural distortion is 12.12%, 11.11% and 16.66% respectively. ► Band gap increases 8.38%, 3.70% and 21.31% respectively

  18. Study of the Al-grading effect in the crystallisation of chalcopyrite CuIn{sub 1−x}Al{sub x}Se{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Martín, S., E-mail: sofia.martin@ciemat.es [CIEMAT, Departamento de Energía, Avda. Complutense, 40, E-28040 Madrid (Spain); Zoppi, G.; Aninat, R.; Forbes, I. [Northumbria Photovoltaics Applications Centre, Northumbria University, Ellison Building, Newcastle upon Tyne NE1 8ST (United Kingdom); Guillén, C. [CIEMAT, Departamento de Energía, Avda. Complutense, 40, E-28040 Madrid (Spain)

    2013-06-15

    Chalcopyrite CuIn{sub 1−x}Al{sub x}Se{sub 2} (CIAS) thin films with an atomic ratio of Al/(In + Al) = 0.4 were grown by a two-stage process onto soda-lime glass substrates. The selenisation was carried out at different temperatures, ranging from 400 °C to 550 °C, for metallic precursors layers evaporated with two different sequences. The first sequence, C1, was evaporated with the Al as the last layer, while in the second one, C2, the In was the last evaporated element. The optical, structural and morphological characterisations led to the conclusion that the precursors sequence determines the crystallisation pathway, resulting in C1 the best option due to the homogeneity of the depth distribution of the elements. The influence of the selenisation temperature was also studied, finding 540 °C as the optimum one, since it allows to achieve the highest band gap value for the C1 sequence and for the given composition. - Highlights: • CIAS chalcopyrite thin films were prepared by a two-stage process. • Different metallic precursors sequences have been evaporated. • The samples have been converted at different selenisation temperatures. • Optical, morphological and structural properties have been studied. • The sequence and the temperatures determine the way towards CIAS formation and crystallization.

  19. Comparative Study of the Defect Point Physics and Luminescence of the Kesterites Cu2ZnSnS4 and Cu2ZnSnSe4 and Chalcopyrite Cu(In,Ga)Se2: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Romero, M. J.; Repins, I.; Teeter, G.; Contreras, M.; Al-Jassim, M.; Noufi, R.

    2012-08-01

    In this contribution, we present a comparative study of the luminescence of the kesterites Cu2ZnSnS4 (CZTS) and Cu2ZnSnSe4 (CZTSe) and their related chalcopyrite Cu(In,Ga)Se2 (CIGSe). Luminescence spectroscopy suggests that the electronic properties of Zn-rich, Cu-poor kesterites (both CZTS and CZTSe) and Cu-poor CIGSe are dictated by fluctuations of the electrostatic and chemical potentials. The large redshift in the luminescence of grain boundaries in CIGSe, associated with the formation of a neutral barrier is clearly observed in CZTSe, and, to some extent, in CZTS. Kesterites can therefore replicate the fundamental electronic properties of CIGSe.

  20. 三株氧化硫硫杆菌的分离与鉴定%Isolation and Characterization of three strains of Acidithiobacillus thiooxidans and its bioleaching of chalcopyrite

    Institute of Scientific and Technical Information of China (English)

    符波; 周洪波; 张倩; 邱冠周

    2008-01-01

    Three strains of mesophilic and acidophilic sulfur-oxidizing bacteria were isolated from coal heap drainage. The bacteria are motile, Gram-negative, rod-shaped, and measures 0.4 to 0.7 by 1 to 2 μm. They grow optimally at 30 ℃ and initial pH 2.0~2.5. The strains grow autotrophically by using elemental sulfur, sodium thiosulfate and potassium tetrathionate as energy sources. The strains can not use organic matter and inorganic minerals including ferrous sulfate, pyrite and chalcopyrite as energy sources. The morphological, biochemical and physiological characterization and analysis based on 16S rRNA gene sequence indicated that the strains are most closely related to Acidithiobacillus thiooxidans (>99% similarity in gene sequence). The presence of sulfur-oxidizing bacteria positively increased the dissolution rate and the percentage recovery of copper from chalcopyrite by producing acid.%从煤堆废水中分离得到3株嗜温嗜酸硫氧化细菌.这3株菌株为革兰氏阴性、菌体大小0.4~0.7 μm×1~2 μm、短杆状运动细菌,其最适生长温度为 30 ℃和最适生长pH 2.0~2.5.它们能够利用元素硫,硫代硫酸钠和连四硫酸钾为能源进行自养生长,不能利用有机物质以及硫酸亚铁、黄铁矿和黄铜矿等无机物质作为能源生长.细菌的形态、生理生化特性研究以及基于16S rRNA序列同源性构建的系统发育树结果表明,这3株细菌初步鉴定为氧化硫硫杆菌.氧化硫硫杆菌能够通过产酸有效促进黄铜矿的浸出速率和浸出率.

  1. Effect of potential on characteristics of surface film on natural chalcopyrite%电位对天然黄铜矿表面膜层性质的影响

    Institute of Scientific and Technical Information of China (English)

    俞娟; 杨洪英; 范有静

    2011-01-01

    Electrochemical behavior of natural chalcopyrite in electrolyte solution containing 5× 10-4 mol/L ethyl xanthate,and the effect of potential on the composition and characteristics of surface film were studied by cyclic voltammetry (CV),scanning electron microscopy (SEM) and electrochemical impedance spectroscopy (EIS).The adsorption of xanthate (X-) occurred on the mineral surface at open-circuit potential (OCP).In the potential range from -0.11 to 0.2 V,the electrochemical reaction related to the formation of the hydrophobic film of dixanthogen (X2) occurred on natural chalcopyrite surface.This surface film had high coverage and large thickness at the potential of 0 V,but it had low coverage and small thickness at the potentials of 0.1 V and 0.2 V.Electrochemical activation started to occur when the potential was higher than 0.2 V,and the film of X2 transformed to plenty of Cu(Ⅱ) and Fe(Ⅲ) oxygen-containing species which had the porous and loose characteristics.%采用循环伏安(CV)、扫描电子显微镜(SEM)和电化学阻抗谱(EIS)研究黄铜矿在含有5×10-4 mol/L乙黄药溶液中的电化学行为以及电位对黄铜矿表面膜层成分和性质的影响.结果表明:在开路电位(OCP)下,天然黄铜矿表面发生黄药阴离子的吸附过程;在阳极电位范围-0.11~0.2 V内,主要发生黄药阴离子氧化形成疏水双黄药膜层的电化学过程.形成的双黄药膜层在电位为0V时具有较高覆盖度和较大的厚度,随着电位的增加表面双黄药膜层的覆盖度和厚度减小.当电位高于0.2 V时,黄铜矿表面发生以自身活化溶解为主的电化学过程,黄铜矿表面由双黄药膜层转化成为大量具有多孔和疏松结构的含有Cu(Ⅱ)和Fe(Ⅲ)的氧化物.

  2. 吉林某难处理含铜金精矿硫脲浸金试验研究%Extraction of Gold from a Refractory Gold Concentrate Containing Chalcopyrite by Thiourea Leaching in Jilin

    Institute of Scientific and Technical Information of China (English)

    马龙

    2011-01-01

    Experimental research on thiourea leaching of gold was carried out on a refractory gold concentrate which contains chalcopyrite, investigating the effects of dosage and concentrate of thiourea, ferric ion and leaching time on gold leaching. When the ration of liquid to solid is 4:1, pH value is 1 and leaching time is 8h under the usual temperature , the leaching rate of gold is improved from 57.14% to 91 %. During the course the leaching rate of copper is less than 2.5% .which has little influence on gold recovery and the following copper recovery.%针对吉林某难处理含铜金精矿进行了硫脲浸金试验研究,考察了硫脲用量、硫脲浓度、三价铁离子浓度和浸出时间等因素对浸金效果的影响.试验结果表明,在矿浆液固比为4:1,矿浆pH值为1,硫脲用量160kg/t时,常温浸出8h,金的浸出率可由全泥氰化浸出的57.14%提升至91%以上.浸金过程中铜的浸出率保持在2.5%以下,铜浸出较少.

  3. Chalcopyrite Nanoparticles as a Sustainable Thermoelectric Material

    Directory of Open Access Journals (Sweden)

    Maninder Singh

    2015-10-01

    Full Text Available In this report, copper iron sulfide nanoparticles with various composition were synthesized by a thermolysis based wet chemical method. These inherently sustainable nanoparticles were then fully characterized in terms of composition, structure, and morphology, as well as for suitability as a thermoelectric material. The merits of the material preparation include a straightforward bulk material formation where particles do not require any specialized treatment, such as spark plasma sintering or thermal heating. The Seebeck coefficient of the materials reveals P-type conductivity with a maximum value of 203 µV/K. The results give insight into how to design and create a new class of sustainable nanoparticle material for thermoelectric applications.

  4. 元素硫对黄铜矿生物浸出行为及群落结构的影响%Relationships among bioleaching performance, additional elemental sulfur,microbial population dynamics and its energy metabolism in bioleaching of chalcopyrite

    Institute of Scientific and Technical Information of China (English)

    夏乐先; 汤露; 夏金兰; 尹礎; 柴立元; 赵小娟; 聂珍媛; 柳建设; 邱冠周

    2012-01-01

    To estimate the relationships among bioleaching performance,additional elemental sulfur (S0),microbial population dynamics and its energy metabolism,bioleaching of chalcopyrite by three typical sulfur- and/or iron-oxidizing bacteria,Acidithiobacillus ferrooxidans,Leptospirillum ferriphilum and Acidithiobacillus thiooxidans with different levels of sulfur were studied in batch shake flask cultures incubated at 30 ℃.Copper dissolution capability (71%) was increased with the addition of 3.193 g/L S0,compared to that (67%) without S0.However,lower copper extraction was obtained in bioleaching with excessive sulfur.Microbial population dynamics during chalcopyrite bioleaching process was monitored by using PCR-restrietion fragment length polymorphism (PCR-RFLP).Additional S0 accelerated the growth of sulfur-oxidizing bacteria,inhibited the iron-oxidizing metabolism and led to the decrease of iron-oxidizing microorganisms,finally affected iron concentration,redox potential and bioleaching performance.It is suggested that mixed iron and sulfur-oxidizing microorganisms with further optimized additional S0 concentration could improve copper recovery from chalcopyrite.%研究3种典型铁/硫代谢菌-Acidithiobacillus ferrooxidans,Leptospirillum ferriphilum及Acidithiobacillus thiooxidans混合浸出黄铜矿过程中铁/硫氧化活性、群落结构(PCR-RFLP)的变化,以及不同浓度的元素硫对其影响.结果发现,加入3.193 g/L元素硫能促进细菌的表观硫氧化活性,改变浸矿体系的群落结构,并进一步影响钝化层的形成、金属离子的溶出,其浸出率(71%)较未添加硫的(67%)有一定程度的提高.而过量的元素硫会抑制铜的浸出(浸出率44%).

  5. Mn掺杂后三元黄铜矿结构半导体CuInTe2的缺陷特征与热电性能∗%Defects and thermo electric p erformance of ternary chalcopyrite CuInTe2-based semiconductors dop ed with Mn

    Institute of Scientific and Technical Information of China (English)

    王鸿翔; 应鹏展; 杨江锋; 陈少平; 崔教林

    2016-01-01

    In thermoelectric (TE) semiconductors, there are three physical parameters that govern the TE performance (i.e. Seebeck coefficient (α), electrical conductivity (σ), and thermal conductivity (κ));they are interrelated, hence it is hard to optimize them simultaneously. In order to improve the TE performance, we need to further explore new materials. Ternary chalcopyrite (diamond-like) I-III-VI2 semiconductors (Eg =1.02 eV) are new materials of the TE family, which have potential in conversion between heat and electricity. Since in the ternary chalcopyrite structure, such as Cu(Ag) MTe2, there is an inherent Coulomb attraction between charged defects M2+Cu(Ag) and 2V−Cu(Ag) (a native defect pair, i.e. , metal M-on-Cu or Ag antisites and two Cu or Ag vacancies), hence the electronic and structural properties can easily be tailored if these two defects, along with the creation of other defects, are modified through the introduciton of foreign elements. Besides, the ternary I-III-VI2 compounds often show tetragonal distortion because u ̸= 0.25,η = c/2a ̸= 1 (here u and η are the anion position displacement parameters, and a and c are the lattice parameters), and the cation–anion distances are not equal (dCu—Te=dIn—Te). Any occupation by foreign elements in the cation sites of I-III-VI2 will cause the redistribution of bond charges between I-VI and III-VI, thus leading to a tiny adjustment of the crystal structure and altering the phonon scattering behavior. In this work, we substitute Mn for Cu in the chalcopyrite CuInTe2 and prepare the Cu-poor Cu1−xInMnxTe2 semiconductors. Investigations of Z-ray patterns after Rietveld refinement reveal that Mn prefers In to Cu lattice sites for low Mn content (x 0.1, and generate both the donor defect Mn+Cu and the acceptor defect Mn−In. In this case, annihilation may occur between these two defects, allowing the reduction in both the defect and carrier concentrations. Because of the annihilation between the two

  6. Re-Os isotopic dating of chalcopyrite from the Abalieke copper-lead deposits in West Kunlun, China%西昆仑阿巴列克铜铅矿床黄铜矿Re-Os定年及地质意义

    Institute of Scientific and Technical Information of China (English)

    张正伟; 漆亮; 沈能平; 游富华; 张中山; 周灵洁

    2011-01-01

    It is a very important and effective method of analyzing the ore-forming processes by taking advantage of geochemistry analytical approaches as well as traditional ways, such as testing the Re-Os, discriminating the paragenetic association of the minerals and the tectonic settings. Seven chalcopyrite and one pyrite samples from the main orebody of Abalieke Cu-Pb deposit are used for Re-Os dating. The chalcopyrite is associated with galenite and dolomite which contain 626 x 10 " ~ 14533 x 10 ~ of Re and 0. 026 x 10 ~0. 36 x 10 "9 of Os respectively, and yield a Hercynina isochron age of 331. 3 ±5. 2Ma. High Re/Os ratio, low Os concentration and highly radiogenic Os isotopic ratios of these samples suggest that they are of crustal origin. The tectonic evolving shows that the southwestern margin of the Tarim block was a passive continental margin in the Late Paleozoic era. Because of the Paleo-Tethys ocean movement during Carboniferous, the depression basin are formed in margin of Tarim craton, comprised lead-zinc deposits in clastic rock-carbonate host stratum that cover up the Devonian. This Re-Os isotopic dating age of chalcopyrite is nearly closed with ore-hosted stratum. Our Re-Os result provides new evidences, showing that Abalieke Cu-Pb deposit experienced the syngenetic ore-forming process in Hercynina Also this study gives important geochemical evidence on such issues; the lead-zinc deposits are mainly sedimentary formation-controlled type; the ore-forming elements mainly came from stratum; mineralization occurred in the joint position between Upper Devonian and Lower Carboniferous, while the rock in which mainly consist of sandstone and carbonatite formation. It can be seen that the metallogenic system of the copper-lead-zinc strata-bound deposits in carbonate rock has a certain complexity and provides wider space for further researches.%除了传统的测试Rb-Sr、Sm-Nd、U-Th-Pb、K-Ar或Ar-Ar等方法来讨论碳酸盐岩层控型铅锌矿的成矿年

  7. Defect-related electronic metastabilities in chalcopyrite compounds

    Energy Technology Data Exchange (ETDEWEB)

    Hammer, Maria S., E-mail: maria.hammer@uni-oldenburg.de [Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg, 26111 Oldenburg (Germany); Neugebohrn, Nils; Riediger, Julia; Neerken, Janet; Ohland, Jörg; Riedel, Ingo [Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg, 26111 Oldenburg (Germany); Kiowski, Oliver; Wischmann, Wiltraud [Zentrum für Sonnenenergie- und Wasserstoff-Forschung Baden-Württemberg (ZSW), Industriestr. 6, 70565 Stuttgart (Germany)

    2014-04-15

    So far, in Cu(In,Ga)Se{sub 2} solar cells the metastable behavior of the key parameters, i.e. open circuit voltage, short circuit current and fill factor, and the corresponding defect physics were typically investigated independently. In order to contribute to this issue, we systematically varied between annealed and light soaked state and investigated the influence of these processes on the solar cell parameters as well as on the defect physics. In this work, we attempt to correlate the key parameters of the solar cells and the defect physics by discussing experimental results obtained from temperature dependent current–voltage measurements (IVT) as well as from capacitance voltage (CV), admittance (AS) and deep-level transient spectroscopy (DLTS). A commonly observed defect contribution in Cu(In,Ga)Se{sub 2} solar cells is the so-called N1 signature. The activation energy of this signature was found to increase upon air-annealing in the dark which goes along with a decrease in the open circuit voltage and the effective doping density. In this paper we will discuss the correlation between annealing-induced shifting of defect energies and the variation of the key parameters.

  8. Structural trends in off stoichiometric chalcopyrite type compound semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Stephan, Christiane

    2011-03-15

    Energy supply is one of the most controversial topics that are currently discussed in our global community. Most of the energy delivered to the customer today has its origin in fossil and nuclear power plants. Indefinable risks and the radioactive waste repository problem of the latter as well as the global scarcity of fossil resources cause the renewable energies to grow more and more important for achieving sustainability. The main renewable energy sources are wind power, hydroelectric power and solar energy. On the photovoltaic (PV) market different materials are competing as part of different kinds of technologies, with the largest contribution still coming from wafer based crystalline silicon solar cells (95 %). Until now thin film solar cells only contribute a small portion to the whole PV market, but large capacities are under construction. Thin film photovoltaic shows a number of advantages in comparison to wafer based crystalline silicon PV. Among these material usage and production cost reduction are two prominent examples. The type of PV materials, which are analyzed in this work, are high potential compounds that are widely used as absorber layer in thin film solar cells. These are compound semiconductors of the type CuB{sup III}C{sup VI}{sub 2} (B{sup III} = In, Ga and C{sup VI} = Se, S). Several years of research have already gone into understanding the efficiency limiting factors for solar cell devices fabricated from this compound. Most of the studies concerning electronic defects are done by spectroscopic methods mostly performed using thin films from different kinds of synthesis, without any real knowledge regarding the structural origin of these defects. This work shows a systematic fundamental structural study of intrinsic point defects that are present within the material at various compositions in CuB{sup III}C{sup VI}{sub 2} compound semiconductors. The study is done on reference powder samples with well determined chemical composition and using advanced diffraction techniques, such as neutron and synchrotron X-ray diffraction. The results show that the main existing defects are found to be copper vacancies and B{sup III}{sub Cu} anti-site defects. Type and concentrations vary with the composition. It is demonstrated that, when assuming spontaneous formation of electrically neutral defect complexes made of these isolated point defects, the density of cationic point defects is reduced by an order of magnitude. This explains why the existence of native cationic point defects may not be the main efficiency limiting factor in thin film solar cells built with a CuB{sup III}C{sup VI}{sub 2} absorber. This pinpoints why the mere presence of native cationic point defects does probably not suffice as main efficiency limiting factor in thin film solar cells based on CuB{sup III}C{sup VI}{sub 2}-type absorbers.

  9. Electrodeposition of chalcopyrite films from ionic liquid electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Shivagan, D.D. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom)]. E-mail: d.shivagan@bath.ac.uk; Dale, P.J. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom); Samantilleke, A.P. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom); Peter, L.M. [Department of Chemistry, University of Bath, BATH BA2 7AY (United Kingdom)]. E-mail: l.m.peter@bath.ac.uk

    2007-05-31

    An air and water stable room-temperature ionic liquid based on choline chloride/urea eutectic mixture has been investigated as a system for the electrodeposition of CuInSe{sub 2} (CIS) and Cu(In,Ga)Se{sub 2} (CIGS) films for photovoltaic applications. Deposition potentials and bath compositions were optimized to obtain Cu-In, Cu-In-Se and Cu-In-Ga-Se precursor films, which were selenized in a tube furnace at 500 deg. C for 30 min to form CIS and CI(G)S films. Photo-electrochemical measurements on these selenized films showed p-type photoconductivity with band gaps of 1.0 eV and 1.09 eV, respectively, for CIS and CIGS. The films were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), photocurrent spectroscopy and electrolyte electro-reflectance spectroscopy (EER)

  10. Photoluminescence spectra of some ternary and quaternary chalcopyrite semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Abou-Elfotouh, F.; Dunlavy, D.J.; Kazmerski, L.L.; Albin, D.; Bachman, K.J.; Menner, R.

    1988-05-01

    Photoluminescence (PL) emission spectra of single crystals and thin films of CuGa/sub x/In/sub 1/..sqrt../sub x/Se/sub 2/ compounds have been investigated at various measuring temperatures, and compared with the emission from CuGaSe/sub 2/ and CuInSe/sub 2/. The observed PL spectra consisted of two groups of emission lines: the near-band-gap group (A) and the lower energy group (B). It was found that the type of emission obtained is determined by the amount of stoichiometry and molecularity deviations. The PL data also showed a correspondence between the defect related transitions from the CuGa/sub x/In/sub 1/..sqrt../sub x/Se/sub 2/ solid solution and CuGaSe/sub 2/ for x<0.5. Based on the intrinsic defect states in the two components CuInSe/sub 2/ and CuGaSe/sub 2/, the predominant defect states transitions in the solid solution are defined for the m<1 and ..delta..S>0. Interpretation of the PL spectra of Se-deficient compounds with m>1 are rather complicated, and much work remains to be done before the defect chemistry of CuGa/sub x/In/sub 1/..sqrt../sub x/Se/sub 2/ could be fully understood.

  11. Theoretical modelling of intermediate band solar cell materials based on metal-doped chalcopyrite compounds

    Energy Technology Data Exchange (ETDEWEB)

    Palacios, P. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM, Ciudad Universitaria s/n, 28040 Madrid (Spain)]. E-mail: pablop@etsit.upm.es; Sanchez, K. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM, Ciudad Universitaria s/n, 28040 Madrid (Spain); Conesa, J.C. [Instituto de Catalisis y Petroleoquimica, CSIC, Marie Curie 2, Cantoblanco, 28049 Madrid (Spain); Fernandez, J.J. [Dpt. de Fisica Fundamental, Universidad Nacional de Educacion a Distancia, 28080, Madrid (Spain); Wahnon, P. [Instituto de Energia Solar and Dpt. de Tecnologias Especiales, ETSI de Telecomunicacion, UPM, Ciudad Universitaria s/n, 28040 Madrid (Spain)

    2007-05-31

    Electronic structure calculations are carried out for CuGaS{sub 2} partially substituted with Ti, V, Cr or Mn to ascertain if some of these systems could provide an intermediate band material able to give a high efficiency photovoltaic cell. Trends in electronic level positions are analyzed and more accurate advanced theory levels (exact exchange or Hubbard-type methods) are used in some cases. The Ti-substituted system seems more likely to yield an intermediate band material with the desired properties, and furthermore seems realizable from the thermodynamic point of view, while those with Cr and Mn might give half-metal structures with applications in spintronics.

  12. Flotation of Chalcopyrite and Molybdenite in the Presence of Organics in Water

    Directory of Open Access Journals (Sweden)

    Maria Sinche-Gonzalez

    2016-10-01

    Full Text Available One of the water constituents that has not been investigated in great detail for potential detrimental effect on mineral flotation is organic matter. This study investigates the effect of natural organic materials contained in water, such as humic, fulvic and tannic acids, on the flotation of copper and molybdenum sulphides in alkaline conditions and in concentrations similar to those found in natural waters. Results show that copper and molybdenum grades decreased with the addition of humic, tannic and fulvic acid in that order, with a larger depression of molybdenite grade and recovery. Adsorption studies using ultraviolet (UV-visible spectroscopy and X-ray photoelectron spectrometer (XPS surface analysis confirmed that these organic materials were adsorbed on the minerals surface. Complimentary analyses of froth characteristics, particle size distribution and fine particles entrainment were also conducted to explain the cause of the negative effect of these organic materials on flotation. The flotation results were explained in terms of the decrease in the hydrophobicity of the mineral surfaces due to the adsorption of hydrophilic groups in these organic materials which then prevent bubble-particle adhesion. The larger detrimental effect of humic acid is due to its higher adsorption on the minerals, high molecular weight and carbon content compared with the other organic acids used.

  13. Experimental verification of optically optimized CuGaSe2 top cell for improving chalcopyrite tandems

    Science.gov (United States)

    Schmid, M.; Caballero, R.; Klenk, R.; Krč, J.; Rissom, T.; Topi, M.; Lux-Steiner, M. Ch.

    2010-07-01

    An efficient tandem solar cell requires a top cell which is highly transparent below the energy gap of its absorber. Previously we had reported on a theoretically optimized CuGaSe2top cell stack based on realistic material properties. It promised a significant increase in optical transparency and, consequently, enhanced CuGaSe2/Cu(In,Ga)Se2tandem efficiency. Here we present the first steps taken towards the experimental realization of this optimized tandem. We started with a mechanically stacked device which achieved 8.5% efficiency. Optical measurements of the improved top cells and corresponding photo current densities of the filtered bottom cell are reported. The experimental findings are in agreement with the optical modeling. These data are used to assess the level of tandem performance that could be accomplished in the near future and to discuss the priorities of further research. This article has been previously published in PV Direct, the former name of EPJ Photovoltaics.

  14. Hard x-ray photoelectron spectroscopy of chalcopyrite solar cell components

    Science.gov (United States)

    Gloskovskii, A.; Jenkins, C. A.; Ouardi, S.; Balke, B.; Fecher, G. H.; Dai, X.-F.; Gruhn, T.; Johnson, B.; Lauermann, I.; Caballero, R.; Kaufmann, C. A.; Felser, C.

    2012-02-01

    Hard x-ray photoelectron spectroscopy is used to examine the partial density of states of Cu(In,Ga)Se2 (CIGSe), a semiconducting component of solar cells. The investigated, thin Cu(In,Ga)Se2 films were produced by multi-stage co-evaporation. Details of the measured core level and valence band spectra are compared to the calculated density of states. The semiconducting type electronic structure of Cu(In,Ga)Se2 is clearly resolved in the hard x-ray photoelectron spectra.

  15. Microbial community succession mechanism coupling with adaptive evolution of adsorption performance in chalcopyrite bioleaching.

    Science.gov (United States)

    Feng, Shoushuai; Yang, Hailin; Wang, Wu

    2015-09-01

    The community succession mechanism of Acidithiobacillus sp. coupling with adaptive evolution of adsorption performance were systematically investigated. Specifically, the μmax of attached and free cells was increased and peak time was moved ahead, indicating both cell growth of Acidithiobacillus ferrooxidans and Acidithiobacillus thiooxidans was promoted. In the mixed strains system, the domination courses of A. thiooxidans was dramatically shortened from 22th day to 15th day, although community structure finally approached to the normal system. Compared to A. ferrooxidans, more positive effects of adaptive evolution on cell growth of A. thiooxidans were shown in either single or mixed strains system. Moreover, higher concentrations of sulfate and ferric ions indicated that both sulfur and iron metabolism was enhanced, especially of A. thiooxidans. Consistently, copper ion production was improved from 65.5 to 88.5 mg/L. This new adaptive evolution and community succession mechanism may be useful for guiding similar bioleaching processes.

  16. Experimental verification of optically optimized CuGaSe2 top cell for improving chalcopyrite tandems*

    Directory of Open Access Journals (Sweden)

    Lux-Steiner M. Ch.

    2010-10-01

    Full Text Available An efficient tandem solar cell requires a top cell which is highly transparent below the energy gap of its absorber. Previously we had reported on a theoretically optimized CuGaSe2 top cell stack based on realistic material properties. It promised a significant increase in optical transparency and, consequently, enhanced CuGaSe2/Cu(In,GaSe2 tandem efficiency. Here we present the first steps taken towards the experimental realization of this optimized tandem. We started with a mechanically stacked device which achieved 8.5% efficiency. Optical measurements of the improved top cells and corresponding photo current densities of the filtered bottom cell are reported. The experimental findings are in agreement with the optical modeling. These data are used to assess the level of tandem performance that could be accomplished in the near future and to discuss the priorities of further research.

  17. Cd-free heterojunctions in chalcopyrite based thin film solar cells; Cd-freie Heterokontakte in Chalkopyrit-basierten Duennschichtsolarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Kieven, David

    2012-02-06

    This thesis took care of the problem to replace the buffer layers Cds and i-ZnO in thin-film solar cells of the layer system p-Cu(In,Ga)(Se,S){sub 2}/CdS/i-ZnO/n{sup +} by a Cd-free buffer layer. The synthesis of the material layers. The synthesis was carried out by the method of cathode sputtering established in the deposition of the n{sup +}-ZnO window layer. Aim was to modify the electronic properties of the studied materials either by the choice of the applied bonding elements or by the choice of the composition in such a way that the basic conditions for buffer layers are fulfilled: Optical transparency and suited band fitting to the absorber material. The analysis of the interfaces between the potential buffer materials and the Cu(In,Ga)(Se,S){sub 2} absorber material considering the conduction-band fitting important for solar cells formed a main topic. Finally suited materials came into application as buffer layers in Cu(In,Ga)(Se,S){sub 2}-based thin-film solar cells. Thereby was of interest, whether efficient solar cells can be fabricated, and whether the photovoltaic parameters open-circuit voltage and short-circuit current density are dominantly influenced by possible interface defects, as they are especially discussed in connection with the sputtering deposition.

  18. Methods for synthesizing semiconductor quality chalcopyrite crystals for nonlinear optical and radiation detection applications and the like

    Energy Technology Data Exchange (ETDEWEB)

    Stowe, Ashley; Burger, Arnold

    2016-05-10

    A method for synthesizing I-III-VI.sub.2 compounds, including: melting a Group III element; adding a Group I element to the melted Group III element at a rate that allows the Group I and Group III elements to react thereby providing a single phase I-III compound; and adding a Group VI element to the single phase I-III compound under heat, with mixing, and/or via vapor transport. The Group III element is melted at a temperature of between about 200 degrees C. and about 700 degrees C. Preferably, the Group I element consists of a neutron absorber and the group III element consists of In or Ga. The Group VI element and the single phase I-III compound are heated to a temperature of between about 700 degrees C. and about 1000 degrees C. Preferably, the Group VI element consists of S, Se, or Te. Optionally, the method also includes doping with a Group IV element activator.

  19. Dispersion of the second harmonic generation from CdGa{sub 2}X{sub 4} (X = S, Se) defect chalcopyrite: DFT calculations

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A.H. [New Technologies – Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Khan, Saleem Ayaz, E-mail: sayaz_usb@yahoo.com [New Technologies – Research Center, University of West Bohemia, Univerzitni 8, 306 14 Pilsen (Czech Republic)

    2014-05-15

    Highlights: • Nonlinear optical properties of CdGa{sub 2}X{sub 4} (X = S, Se) were investigated. • The compounds have large uniaxial anisotropy and large negative birefringence. • The second order susceptibility and the first hyperpolarizability were calculated. • CdGa{sub 2}Se{sub 4} posses huge second harmonic generation. - Abstract: All electron full potential linear augmented plane wave method was used for calculating the nonlinear optical susceptibilities of CdGa{sub 2}X{sub 4} (X = S, Se) within the framework of density functional theory. The exchange correlation potential was solved by recently developed modified Becke and Johnson (mBJ) approximation. The crystal structure of CdGa{sub 2}S{sub 4} and CdGa{sub 2}Se{sub 4} reveals a large uniaxial dielectric anisotropy ensuing the birefringence of −0.036 and −0.066 which make it suitable for second harmonic generation. The second order susceptibility |χ{sub ijk}{sup (2)}(ω)| and microscopic first hyperpolarizability β{sub ijk}(ω) were calculated. The calculated |χ{sub 123}{sup (2)}(ω)| and |χ{sub 312}{sup (2)}(ω)| static values for the dominant components found to be 18.36 pm/V and 22.23 pm/V for CdGa{sub 2}S{sub 4} and CdGa{sub 2}Se{sub 4}. Both values shifted to be 60.12 pm/V and 108.86 pm/V at λ = 1064 nm. The calculated values of β{sub 123}(ω) is 6.47 × 10{sup −30} esu at static limit and 12.42 × 10{sup −30} esu at λ = 1064 nm for CdGa{sub 2}S{sub 4}, whereas it is 8.82 × 10{sup −30} esu at static limit and 20.51 × 10{sup −30} esu at λ = 1064 nm for CdGa{sub 2}Se{sub 4}. The evaluation of second order susceptibilities and first hyperpolarizabilties suggest that CdGa{sub 2}X{sub 4} possess huge second harmonic generation.

  20. Density of electronic states and dispersion of optical functions of defect chalcopyrite CdGa{sub 2}X{sub 4} (X = S, Se): DFT study

    Energy Technology Data Exchange (ETDEWEB)

    Reshak, A.H. [Institute of Complex Systems, FFPW, CENAKVA, University of South Bohemia in CB, Nove Hrady 37333 (Czech Republic); Center of Excellence Geopolymer and Green Technology, School of Material Engineering, University Malaysia Perlis, 01007 Kangar, Perlis (Malaysia); Khan, Saleem Ayaz, E-mail: sayaz_usb@yahoo.com [Institute of Complex Systems, FFPW, CENAKVA, University of South Bohemia in CB, Nove Hrady 37333 (Czech Republic)

    2013-11-15

    Graphical abstract: - Highlights: • FPLAPW method is used for calculating the electronic and optical properties of CdGa{sub 2}X{sub 4}. • Electronic and optical properties were calculated using LDA, GGA, EVGGA and mBJ. • Band gap conformed that CdGa{sub 2}X{sub 4} are semiconductors fit for UV and visible light. • The ECD shows that change in the bond length and bond nature affect the band gap. • The dielectric tensor components and its derivatives show considerable anisotropy. - Abstract: A density functional theory (DFT) based on full potential linear augmented plane wave (FPLAPW) was used for calculating the electronic structure, charge density and optical properties of CdGa{sub 2}X{sub 4} (X = S, Se) compounds. Local density approximation (LDA), generalized gradient approximation (GGA), Engle Vasko generalized gradient approximation (EVGGA) and recently modified Becke–Johnson (mBJ) were applied to calculate the band structure, total and partial density of states. The investigation of band structures and density of states of CdGa{sub 2}X{sub 4} (X = S, Se) elucidate that mBJ potential show close agreement to the experimental results. The mBJ potential was selected for further explanation of optical properties of CdGa{sub 2}X{sub 4} (X = S, Se). The study of electronic charge density contours shows that change in the bond lengths and bond nature affect the band gap of the compounds. The two non-zero dielectric tensor components and its derivatives show considerable anisotropy between the perpendicular and parallel components. The present work provide accurate information about the combination (hybridization) of orbital, formation of bands and dispersion of non-zero tensor components of CdGa{sub 2}X{sub 4} (X = S, Se)

  1. Clean thermal decomposition of tertiary-alkyl metal thiolates to metal sulfides: environmentally-benign, non-polar inks for solution-processed chalcopyrite solar cells

    Science.gov (United States)

    Heo, Jungwoo; Kim, Gi-Hwan; Jeong, Jaeki; Yoon, Yung Jin; Seo, Jung Hwa; Walker, Bright; Kim, Jin Young

    2016-11-01

    We report the preparation of Cu2S, In2S3, CuInS2 and Cu(In,Ga)S2 semiconducting films via the spin coating and annealing of soluble tertiary-alkyl thiolate complexes. The thiolate compounds are readily prepared via the reaction of metal bases and tertiary-alkyl thiols. The thiolate complexes are soluble in common organic solvents and can be solution processed by spin coating to yield thin films. Upon thermal annealing in the range of 200–400 °C, the tertiary-alkyl thiolates decompose cleanly to yield volatile dialkyl sulfides and metal sulfide films which are free of organic residue. Analysis of the reaction byproducts strongly suggests that the decomposition proceeds via an SN1 mechanism. The composition of the films can be controlled by adjusting the amount of each metal thiolate used in the precursor solution yielding bandgaps in the range of 1.2 to 3.3 eV. The films form functioning p-n junctions when deposited in contact with CdS films prepared by the same method. Functioning solar cells are observed when such p-n junctions are prepared on transparent conducting substrates and finished by depositing electrodes with appropriate work functions. This method enables the fabrication of metal chalcogenide films on a large scale via a simple and chemically clear process.

  2. Study on Several Complicated Factors Effect in Bacterial Leaching of Chalcopyrite%黄铜矿细菌浸出过程中的多因素影响

    Institute of Scientific and Technical Information of China (English)

    任浏祎; 覃文庆; 王军; 张雁生; 何小娟

    2008-01-01

    运用取自大宝山(简称DB)的嗜酸氧化亚铁硫杆菌(Acidithiobacillus ferrooxidans,简称A.f)和嗜酸氧化硫硫杆菌(Acidi-thiobacillus thiooxidans,简称A.t)的混合菌对广东某硫化铜矿的黄铜矿进行摇瓶浸出试验研究.结果表明,黄铜矿摇瓶细菌浸出率受菌种、矿浆浓度、pH值、接种量多种因素的影响.细菌浸出黄铜矿的适宜条件为温度30℃,矿浆浓度5%,pH值为2.0,接种量为3×107个/mL.

  3. Research and development of photovoltaic power system. Optimization of bandgap of chalcopyrite semiconductors; Taiyoko hatsuden system no kenkyu kaihatsu. Kinseitaihaba no saitekika no kenkyu

    Energy Technology Data Exchange (ETDEWEB)

    Konagai, M. [Tokyo Institute of Technology, Tokyo (Japan). Faculty of Engineering

    1994-12-01

    This paper reports the result obtained during fiscal 1994 on research on research on optimization of bandgap in thin film compound solar cells. In research on Cu(InGa)Se2 thin film solar cells by using a gas phase selenide making process, discussions were given on optimizing the following three processes: a process to raise temperature of a precursor film formed at a substrate temperature of about 150{degree}C, a selenide making process to perform annealing at about 500{degree}C, and a temperature reducing process. Good characteristics were obtained when selenium amount in the precursor is about 50%. In a bandgap control viewpoint, it was found that the conversion efficiency decreases rapidly when Ga composition is higher than 50%. A conversion efficiency of 14.9% was obtained to date at the Ga/(In+Ga) ratio of 0.4. In research on Cu(InGa)Se2 thin film solar cells by using a simultaneous deposition method, a conversion efficiency of 13.5% was obtained at a bandgap width of about 1.3 eV during research on manufacturing ZnO/CdS/Cu(InGa)Se2 thin film solar cells by using the simultaneous deposition method. Research has been carried out on manufacturing Cu(InGa)Se2 thin film solar cells using ZnSe interface layers. 8 figs.

  4. Hybrid particles and associated methods

    Science.gov (United States)

    Fox, Robert V; Rodriguez, Rene; Pak, Joshua J; Sun, Chivin

    2015-02-10

    Hybrid particles that comprise a coating surrounding a chalcopyrite material, the coating comprising a metal, a semiconductive material, or a polymer; a core comprising a chalcopyrite material and a shell comprising a functionalized chalcopyrite material, the shell enveloping the core; or a reaction product of a chalcopyrite material and at least one of a reagent, heat, and radiation. Methods of forming the hybrid particles are also disclosed.

  5. Identifying the Electronic Properties Relevant to Improving the Performance of High Band-Gap Copper Based I-III-VI2 Chalcopyrite Thin Film Photovoltaic Devices: Final Subcontract Report, 27 April 2004-15 September 2007

    Energy Technology Data Exchange (ETDEWEB)

    Cohen, J. D.

    2008-08-01

    This report summarizes the development and evaluation of higher-bandgap absorbers in the CIS alloy system. The major effort focused on exploring suitable absorbers with significant sulfur alloying in collaboration with Shafarman's group at the Institute of Energy Conversion. Three series of samples were examined; first, a series of quaternary CuIn(SeS)2-based devices without Ga; second, a series of devices with pentenary Cu(InGa)(SeS)2 absorbers in which the Se-to-S and In-to-Ga ratios were chosen to keep the bandgap nearly constant, near 1.52 eV. Third, based on the most-promising samples in those two series, we examined a series of devices with pentenary Cu(InGa)(SeS)2 absorbers with roughly 25 at.% S/(Se+S) ratios and varying Ga fractions. We also characterized electronic properties of several wide-bandgap CuGaSe2 devices from both IEC and NREL. The electronic properties of these absorbers were examined using admittance spectroscopy, drive-level capacitance profiling, transient photocapacitance, and transient photocurrent optical spectroscopies. The sample devices whose absorbers had Ga fraction below 40 at.% and S fractions above 20 at.% but below 40% exhibited the best electronic properties and device performance.

  6. Screened-exchange density functional theory description of the electronic structure and phase stability of the chalcopyrite materials AgInSe2 and AuInSe2

    Science.gov (United States)

    Kim, Namhoon; Martin, Pamela Peña; Rockett, Angus A.; Ertekin, Elif

    2016-04-01

    We present a systematic assessment of the structural properties, the electronic density of states, the charge densities, and the phase stabilities of AgInSe2 and AuInSe2 using screened-exchange hybrid density functional theory, and compare their properties to those of CuInSe2. For AgInSe2, hybrid density functional theory properly captures several experimentally measured properties, including the increase in the band gap and the change in the direction of the lattice distortion parameter u in comparison to CuInSe2. While the electronic properties of AuInSe2 have not yet been experimentally characterized, we predict it to be a small gap (≈0.15 eV) semiconductor. We also present the phase stability of AgInSe2 and AuInSe2 according to screened-exchange density functional theory, and compare the results to predictions from conventional density functional theory, results tabulated from several online materials data repositories, and experiment (when available). In comparison to conventional density functional theory, the hybrid functional predicts phase stabilities of AgInSe2 in better agreement with experiment: discrepancies in the calculated formation enthalpies are reduced by approximately a factor of 3, from ≈0.20 eV/atom to ≈0.07 eV/atom, similar to the improvement observed for CuInSe2. We further predict that AuInSe2 is not a stable phase, and can only be present under nonequilibrium conditions.

  7. Effects of Post-heat Treatment on Performance of Chalcopyrite CuInSe2 Film Prepared by SILAR Method%热处理对SILAR法制备CulnSe2薄膜性能的影响

    Institute of Scientific and Technical Information of China (English)

    杨建立; 靳正国; 石勇; 李春艳; 安贺松

    2005-01-01

    @@ 0引言 铜铟硒(CIS)具有合适的带隙、高光吸收系数、适当的电荷密度和迁移率,是一种用于薄膜太阳能电池的备受关注的吸收材料[1].目前CuInSe2薄膜已采用多种方法进行制备,如金属前驱体硒化法[2]、共沉积法[3]、溅射法[4]、电沉积法[5]和化学气相沉积法[6]等.

  8. 磁控溅射法制备CIGSe吸收层的工艺与性能研究%PROCESS AND PERFORMANCE OF CHALCOPYRITE CIGSe ABSORBERS FABRICATED BY MAGNETRON SPUTTERING

    Institute of Scientific and Technical Information of China (English)

    栾和新; 庄大明; 张弓; 刘江

    2013-01-01

    采用中频交流磁控溅射方法直接溅射CIGSe靶材,制备得到用于太阳电池吸收层的CIGSe薄膜.采用SEM、XRD、Raman、XRF、Hall等方法观察和分析主要工艺参数基底温度和溅射气压对薄膜表面形貌、组织结构、成分、电阻率以及载流子浓度的影响.结果表明,基底温度在250℃以上时,薄膜的黄铜矿相特征明显;当基底温度在250 ~ 300℃时,薄膜的电阻率和载流子浓度在理想范围之内.提高溅射气压,薄膜的沉积速率降低,当溅射气压达到0.7 ~0.9Pa时,溅射速率趋于稳定;溅射气压增大,薄膜的结晶性增强,溅射气压达到0.7Pa时,薄膜的XRD特征峰较明显;提高溅射气压,薄膜的电阻率降低,载流子浓度升高,当溅射气压达到0.7Pa时,薄膜电阻率和载流子浓度在理想范围之内.基底温度和溅射气压对薄膜成分无影响,薄膜成分主要由靶材成分决定.

  9. Sulfur/iron oxidation activity of three typical bioleaching bacteria and sulfur speciation in bioleaching of chalcopyrite%3种典型能量代谢菌浸出黄铜矿及其硫形态的转化

    Institute of Scientific and Technical Information of China (English)

    彭安安; 汤露; 夏金兰; 夏乐先; 赵小娟; 聂珍媛; 朱薇

    2012-01-01

      比较了3种典型嗜中温铁/硫代谢菌——Acidithiobacillus ferrooxidans、Leptospirillum ferriphilum 及Acidithiobacillus thiooxidans单独及混合浸出黄铜矿过程中细菌硫氧化、铁氧化情况。同时利用XRD、硫的K边X射线吸收近边结构光谱(XANES)等分析手段研究3种细菌单独/混合浸出黄铜矿过程中矿物组成成分和矿物表面硫的形态变化。结果表明:在浸出初期电位低于400 mV (vs SCE)时,黄铜矿的浸出速率较快,此后电位迅速升高至540 mV,黄铜矿浸出速率明显变慢。混合菌浸出时体系的硫/铁氧化活性较单一菌高,根据XANES拟合分析发现,混合菌浸出时矿物表面元素硫及黄钾铁矾积累量明显减少,浸出初期辉铜矿产量明显高于单一细菌浸出的。

  10. Synthesis and crystal structure of three new quaternary compounds in the system (Cu-III-Se{sub 2}){sub 1-x}ZnSe{sub x} (III = Al, Ga, In), formed by Zn incorporation in Cu-III-Se{sub 2} chalcopyrite s

    Energy Technology Data Exchange (ETDEWEB)

    Delgado, G. E. [Universidad de Los Andes, Facultad de Ciencias, Departamento de Quimica, Laboratorio de Cristalografia, 5101 Merida (Venezuela, Bolivarian Republic of); Grima G, P.; Quintero, M., E-mail: gerzon@ula.ve [Universidad de Los Andes, Facultad de Ciencias, Departamento de Fisica, Centro de Estudios de Semiconductores, 5101 Merida (Venezuela, Bolivarian Republic of)

    2016-11-01

    The crystal structure of the chalcogenide alloys CuZnAlSe{sub 3}, CuZnCaSe{sub 3} and CuZnInSe{sub 3}, new members of the system I-II-III-VI{sub 3}, were characterized using X-ray powder diffraction data. All materials crystallize in the tetragonal space group P{sub -4} 2{sub c} (N 112) with a CuFeInSe{sub 3}- type structure. (Author)

  11. Characterization of iron- and sulphide mineral-oxidizing moderately thermophilic acidophilic bacteria from an Indonesian auto-heating copper mine waste heap and a deep South African gold mine.

    Science.gov (United States)

    Kinnunen, Päivi H-M; Puhakka, Jaakko A

    2004-10-01

    Iron- and chalcopyrite-oxidizing enrichment cultures were obtained at 50 degrees C from acidic, high-temperature, copper/gold mine environments in Indonesia and South Africa. Over 90% copper yield was obtained from chalcopyrite concentrate with the Indonesian enrichment in 3 months with 2% solids concentration, when pH was maintained at around 2. Neither addition of silver cations nor an enhanced nutrient concentration influenced chalcopyrite leaching. Excision and sequencing of bands from denaturing gradient gel electrophoresis of the amplified partial 16S rRNA gene showed that the enrichment cultures from different environments in South Africa and Indonesia were very simple, and similar. Chalcopyrite concentrate supported a simpler and different community than Fe2+. The members of the enrichment cultures were closely related to Sulfobacillus yellowstonensis and Sulfobacillus acidophilus.

  12. Modelling Defects Acceptors And Determination Of Electric Model From The Nyquist Plot And Bode In Thin Film CIGS

    Directory of Open Access Journals (Sweden)

    Demba Diallo

    2015-08-01

    Full Text Available Abstract The performance of the chalcopyrite material CuInGaSe2 CIGS used as an absorber layer in thin-film photovoltaic devices is significantly affected by the presence of native defects. Multivalent defects e.g. double acceptors or simple acceptor are important immaterial used in solar cell production in general and in chalcopyrite materials in particular. We used the thin film solar cell simulation software SCAPS to enable the simulation of multivalent defects with up to five different charge states.Algorithms enabled us to simulate an arbitrary number of possible states of load. The presented solution method avoids numerical inaccuracies caused by the subtraction of two almost equal numbers. This new modelling facility is afterwards used to investigate the consequences of the multivalent character of defects for the simulation of chalcopyrite based CIGS. The capacitance increase with the evolution of the number of defects C- f curves have found to have defect dependence.

  13. Methods for forming particles

    Energy Technology Data Exchange (ETDEWEB)

    Fox, Robert V.; Zhang, Fengyan; Rodriguez, Rene G.; Pak, Joshua J.; Sun, Chivin

    2016-06-21

    Single source precursors or pre-copolymers of single source precursors are subjected to microwave radiation to form particles of a I-III-VI.sub.2 material. Such particles may be formed in a wurtzite phase and may be converted to a chalcopyrite phase by, for example, exposure to heat. The particles in the wurtzite phase may have a substantially hexagonal shape that enables stacking into ordered layers. The particles in the wurtzite phase may be mixed with particles in the chalcopyrite phase (i.e., chalcopyrite nanoparticles) that may fill voids within the ordered layers of the particles in the wurtzite phase thus produce films with good coverage. In some embodiments, the methods are used to form layers of semiconductor materials comprising a I-III-VI.sub.2 material. Devices such as, for example, thin-film solar cells may be fabricated using such methods.

  14. Copper hydrometallurgy-current status,preliminary economics,future direction and positioning versus smelting

    Institute of Scientific and Technical Information of China (English)

    J.Peacey; GUO Xian-jian; E.Robles

    2004-01-01

    The heap leaching of oxide copper ores with copper cathode recovery by solvent extraction and electrowinning is now well established as a low-cost method of copper recovery. This technology has recently been applied successfully to mixed oxide and chalcocite ores, notably in Chile at Cerro Colorado, Quebrada Blanca and Zaldivar.Currently, there are significant development efforts underway to try to extend heap leaching to chalcopyrite ores.The success of heap leaching/SX/EW has also led to a revival in the development of hydrometallurgical processes to recover copper from chalcopyrite and other copper concentrates. The current status of copper hydrometallurgy is reviewed and the most commercially attractive potential applications are explored. The advantages and disadvantages of the hydrometallurgical treatment of chalcopyrite concentrates and its preliminary economics are compared with those for the current best practices in copper smelting and refining.

  15. Leptosririllum ferrooxidans-sulfide mineral interactions with reference to bioflotation nad bioflocculation

    Institute of Scientific and Technical Information of China (English)

    A.VILINSKA; K.HANUMANTHA RAO

    2008-01-01

    The adhesion of ferrous ions grown Leptospirillum ferrooxidans cells on pyrite and chalcopyrite minerals was investigated through adsorption,Zeta-potential and diffuse reflectance FT-IR measurements.The influence of bacterial species on minerals floatability was determined by Hallimond flotation tests while the flocculation behaviour was examined by Turbiscan measurements.The minerals iso-electric point (pH 6.5-7.5) after interaction with bacterial cells shifted towards cells iso-electric point (pH 3.3),indicating the chemical nature of cells adsorption on mineral surfaces.The FT-IR spectra of minerals treated with bacterial cells showed the presence of all the cell functional groups signifying cells adsorption.The bacterial cells adsorption on chalcopyrite was higher compared with pyrite,which agreed with cells greater depression effect on chalcopyrite flotation and pronounced flocculation behaviour in comparison with pyrite.

  16. Effect of Flotation Reagents on the Cake Moisture of Copper Concentrate

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    The effect of reagents used in separating chalcopyrite from pyrite on the cake moisture of the copper concentrate at Daye Iron Mine Mineral Processing Plant was investigated. The results showed that the dosage of lime used for depressing pyrite was the main factor that increased the filter cake moisture of copper concentrate. With increasing the dosage of lime, the cake moisture of copper concentrate increased sharply. The cause was concluded to be the addition of lime to the pulp, which resulted in the formation of floc and a high pH value. The collector Z-200#, used for collecting chalcopyrite, had, as well, an adverse effect on the cake moisture of copper concentrate, but its effect was inferior in respect to that of lime. The cake moisture of copper concentrate can be decreased by changing the method with which lime is added and the pH value of pulp is regulated. The experiment results showed that the sulfuric acid was the best regulator. When the clarified liquor of lime was used as a depressant and the pH value of the pulp was regulated to 6.5€?7.0 by adding sulfuric acid, the cake moisture of copper concentrate was reduced from 15.49% to 13.13%. The examination of chalcopyrite surface by using ESCA (Electron Spectroscopy for Chemical Analysis) showed that calcium sulfate and iron hydroxide had formed on the surface of chalcopyrite when lime was added to the pulp. The formation of calcium sulfate and iron hydroxide on its surface increased the hydrophilicity of chalcopyrite so that its cake moisture increased. The addition of sulfuric acid to the pulp not only removed the calcium sulfate, but also reduced the concentration of iron hydroxide on the surface of chalcopyrite so that the cake moisture of copper concentrate was decreased.

  17. Synthesis and structures of metal chalcogenide precursors

    Science.gov (United States)

    Hepp, Aloysius F.; Duraj, Stan A.; Eckles, William E.; Andras, Maria T.

    1990-01-01

    The reactivity of early transition metal sandwich complexes with sulfur-rich molecules such as dithiocarboxylic acids was studied. Researchers recently initiated work on precursors to CuInSe2 and related chalcopyrite semiconductors. Th every high radiation tolerance and the high absorption coefficient of CuInSe2 makes this material extremely attractive for lightweight space solar cells. Their general approach in early transition metal chemistry, the reaction of low-valent metal complexes or metal powders with sulfur and selenium rich compounds, was extended to the synthesis of chalcopyrite precursors. Here, the researchers describe synthesis, structures, and and routes to single molecule precursors to metal chalcogenides.

  18. Reliable wet-chemical cleaning of natively oxidized high-efficiency Cu(In,Ga)Se2 thin-film solar cell absorbers

    Science.gov (United States)

    Lehmann, Jascha; Lehmann, Sebastian; Lauermann, Iver; Rissom, Thorsten; Kaufmann, Christian A.; Lux-Steiner, Martha Ch.; Bär, Marcus; Sadewasser, Sascha

    2014-12-01

    Currently, Cu-containing chalcopyrite-based solar cells provide the highest conversion efficiencies among all thin-film photovoltaic (PV) technologies. They have reached efficiency values above 20%, the same performance level as multi-crystalline silicon-wafer technology that dominates the commercial PV market. Chalcopyrite thin-film heterostructures consist of a layer stack with a variety of interfaces between different materials. It is the chalcopyrite/buffer region (forming the p-n junction), which is of crucial importance and therefore frequently investigated using surface and interface science tools, such as photoelectron spectroscopy and scanning probe microscopy. To ensure comparability and validity of the results, a general preparation guide for "realistic" surfaces of polycrystalline chalcopyrite thin films is highly desirable. We present results on wet-chemical cleaning procedures of polycrystalline Cu(In1-xGax)Se2 thin films with an average x = [Ga]/([In] + [Ga]) = 0.29, which were exposed to ambient conditions for different times. The hence natively oxidized sample surfaces were etched in KCN- or NH3-based aqueous solutions. By x-ray photoelectron spectroscopy, we find that the KCN treatment results in a chemical surface structure which is - apart from a slight change in surface composition - identical to a pristine as-received sample surface. Additionally, we discover a different oxidation behavior of In and Ga, in agreement with thermodynamic reference data, and we find indications for the segregation and removal of copper selenide surface phases from the polycrystalline material.

  19. 我国赣中XS铜钨矿床金属矿物标型特征研究及其实际意义

    Institute of Scientific and Technical Information of China (English)

    徐国风

    1981-01-01

    Typomorphic characteristics of ore minerals are discussed from a theoretical approach,examplified by studies on wolframite,chalcopyrite,pyrite,pyrrhotite,marmatite,molybdenite,arsenopyrite,and cassiterite from XS coppertungsten deposit Valuable information can be obtained on ore genesis from studies on typomorphic characteristics in terms of chemical composition,physical property,morphology and crystal structure.

  20. Cu isotope geochemistry of volcanogenic massive sulphide deposits of the eastern Pontides, Turkey

    Energy Technology Data Exchange (ETDEWEB)

    Housh, T B [Department of Geological Sciences, University of Texas at Austin, 1 University Station C1100, Austin, TX 78712 (United States); Ciftci, E [Department of Geological Engineering, Nigde University, 51245 Nigde (Turkey)], E-mail: housh@mail.utexas.edu

    2008-07-01

    A large number of volcanogenic massive sulfide (VMS) deposits are associated with Late Cretaceous to Eocene arc-like volcanic rocks in the eastern Pontides of NE Turkey. Cu isotope studies on thirteen VMS and two vein deposits were undertaken to examine the nature of copper isotope variations and to compare these with other VMS and black smoker deposits. {phi}{sup 65}Cu of chalcopyrite from these deposits range between +0.34 and -0.62 per mille . Chalcopyrite from the VMS deposits of the eastern Pontides have a mean {phi}{sup 65}Cu = -0.13 per mille . {phi}{sup 65}Cu of chalcopyrite is generally heavier than that of corresponding bornite. The range of {phi}{sup 65}Cu for chalcopyrite from VMS deposits in the eastern Pontides is larger than that observed from Alexandrinka, a Devonian VMS deposit in the southern Urals, but is significantly smaller than the up to 3 per mille variations observed from individual modern sea-floor hydrothermal fields along modern mid-ocean ridges. The range of Cu isotope variation in VMS deposits from the eastern Pontides is interpreted to result from processes related to both oxidation and leaching of previously deposited copper by seawater and to its subsequent deposition elsewhere in the hydrothermal system.

  1. Geology, petrography, geochemistry, and genesis of sulfide-rich pods in the Lac des Iles palladium deposits, western Ontario, Canada

    Science.gov (United States)

    Duran, Charley J.; Barnes, Sarah-Jane; Corkery, John T.

    2016-04-01

    The Lac des Iles Pd deposits are known for their Pd-rich sulfide-poor mineralization. However, previously undocumented sulfide-rich pods also occur within the intrusion that hosts the deposits. Given the complex magmatic and hydrothermal history of the mineralization at Lac des Iles, the sulfide-rich pods could have crystallized from magmatic sulfide liquids or precipitated from hydrothermal fluids. Sulfide-rich pods occur throughout the stratigraphy, in all rock types, and along comagmatic shear zones, and contain net-textured to massive sulfides. They can be divided into four main groups based on the variation in mineral assemblages: (1) pyrrhotite-pentlandite ± pyrite-chalcopyrite-magnetite-ilmenite; (2) chalcopyrite ± pyrrhotite-pentlandite-pyrite-magnetite-ilmenite; (3) pyrite ± pentlandite-chalcopyrite-pyrrhotite-magnetite-ilmenite; and (4) magnetite ± ilmenite-pyrrhotite-pentlandite-pyrite-chalcopyrite. Whole rock metal contents and S isotopic compositions do not change with the amount of pyrite present, except for slight enrichments in As and Bi. The presence of an essentially magmatic sulfide mineral assemblage (pyrrhotite-pentlandite ± chalcopyrite) with pentlandite exsolution flames in pyrrhotite in some pods suggests that the pods crystallized from magmatic sulfide liquids. The very low Cu contents of the pods suggests that they are mainly cumulates of monosulfide solid solution (MSS). We propose a model whereby sulfide liquids were concentrated into dilation zones prior to crystallizing cumulus MSS. Intermediate solid solution crystallized from the fractionated liquids at the edges of some pods leaving residual liquids enriched in Pt, Pd, Au, As, Bi, Sb, and Te. These residual liquids are no longer associated with the pods. During subsequent alteration, pyrite replaced MSS/pyrrhotite, but this did not affect the platinum-group element contents of the pods.

  2. Lixiviación de la calcopirita en medios clorurados

    Directory of Open Access Journals (Sweden)

    Ibáñez, T.

    2013-04-01

    Full Text Available The aim of this investigation is to determinate the effects of parameters and additives on the kinetics of dissolution of chalcopyrite on moderated conditions by means of dissolutions test with chalcopyrite concentrate and pure chalcopyrite in shake flasks and instrumented stirred reactors. A study of the dissolution of chalcopyrite in chloride solutions has demonstrated that the rate of dissolution of chalcopyrite is strongly dependent on the potential of the solution within a range of 540 to 630 mV (versus SHE. Leaching at pH around 2.5 results in increased rates of copper dissolution suggesting the possibility to keep the solution potential within the range. Both pyrite and silver ions enhance the dissolution of chalcopyrite and this effect increases when both species are present. The MnO2 has a negative effect on the dissolution increasing the solution potential to values where the rate decreases considerably.El objetivo de esta investigación es determinar el efecto de parámetros y aditivos (MnO2 - iones de plata - pirita en la cinética de disolución de la calcopirita mediante pruebas de disolución con concentrado de calcopirita y calcopirita natural en matraces y reactores agitados mecánicamente bajo condiciones moderadas. La disolución de la calcopirita en medios clorurados es dependiente del potencial de la solución, obteniéndose valores de velocidad aceptables dentro de los 540 y 630 mV (SHE. El pH alrededor de los 2,5 permite mantener los potenciales de solución en valores donde la calcopirita lixivia a velocidades aceptables debido a que ocurre la precipitación de hierro. Tanto la pirita como los iones de plata catalizan la disolución y el efecto es mayor con ambas especies presentes. El MnO2 posee un efecto negativo en la disolución debido a que aumenta el potencial de la solución a valores donde la velocidad disminuye considerablemente.

  3. Synthesis of CulnS_2 nanocrystals and their structural transformation triggered by lisand exchange

    Institute of Scientific and Technical Information of China (English)

    KATSUHIRO Nose; YUKI Soma; TAKAHISA Omata; SHINYA Otsuka-Yao-Matsuo

    2009-01-01

    Chalcopyrite-type CulnS_2 NCs was synthesized by the hot-soap method.Mixed solutions,Cul and InCI_3 dissolved in the mixture of the tri-octylphosphite and 1-octadecene and the sulfur dissolved in tri-phenylphosphite,were used as source solutions;the hexadecylamine was additionally mixed as a surfactant before the reaction.It was observed that the product CulnS_2 NCs structurally transformed from the chalcopyrite(CP)-or zincblende(ZB)-to the wurtzite(WZ)-type depending on the amount of the surfactant and a storage time after the surfactant addition.Very weak photoluminescence in the nearinfrared region was observed for the CP-or ZB-type NCs.This band was attributable to the electronhole recombination via defect levels.No photoluminescence was detected for the wurtzite-type NCs.

  4. The (CuGaSe{sub 2}){sub 1-x}(MgSe){sub x} alloy system (0{<=}x{<=}0.5): X-ray diffraction, energy dispersive spectrometry and differential thermal analysis

    Energy Technology Data Exchange (ETDEWEB)

    Grima Gallardo, P.; Munoz, M.; Ruiz, J. [Centro de Estudios en Semiconductores (C.E.S.), Dpto. Fisica, Fac. Ciencias, La Hechicera, Merida (Venezuela); Delgado, G.E. [Laboratorio de Cristalografia, Dpto. Quimica, Fac. Ciencias, Universidad de Los Andes, Merida 5101 (Venezuela); Briceno, J.M. [Laboratorio de Analisis Quimico y Estructural (LAQUEM), Dpto. Fisica, Fac. Ciencias, La Hechicera, Merida (Venezuela)

    2004-07-01

    The (CuGaSe{sub 2}){sub 1-x}(MgSe){sub x} alloy system (0=}0.15. All the alloys showed the chalcopyrite structure and the lattice parameters of the unit cell do not follow a linear behavior but showed a soft local maximum at x {proportional_to} 0.15. In the single-phase field, the increasing behavior of the lattice parameters can be reproduced using an extension for quaternary alloys of Jaffe and Zunger's model for chalcopyrites. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Extraction of Copper from Malanjkhand Low-Grade Ore by Bacillus stearothermophilus.

    Science.gov (United States)

    Singh, Sradhanjali; Sukla, Lala Behari; Mishra, Baroda Kanta

    2011-10-01

    Thermophilic bacteria are actively prevalent in hot water springs. Their potential to grow and sustain at higher temperatures makes them exceptional compare to other microorganism. The present study was initiated to isolate, identify and determine the feasibility of extraction of copper using thermophilic heterotrophic bacterial strain. Bacillus stearothermophilus is a thermophilic heterotrophic bacterium isolated from hot water spring, Atri, Orissa, India. This bacterium was adapted to low-grade chalcopyrite ore and its efficiency to solubilize copper from Malanjkhand low-grade ore was determined. The low-grade copper ore contains 0.27% Cu, in which the major copper-bearing mineral is chalcopyrite associated with other minerals present as minor phase. Variation in parameters such as pulp-density and temperatures were studied. After 30 days of incubation, it was found that Bacillus stearothermophilus solubilize copper up to 81.25% at pH 6.8 at 60°C.

  6. Isotopic tracing of ore-forming source materials for Dexing porphyry copper deposit of Jiangxi, China

    Institute of Scientific and Technical Information of China (English)

    Peng QIAN; Jianjun LU

    2008-01-01

    Dexing copper deposit is the biggest porphyry copper deposit in China. By researching isotopes of C,Si and Cu from the samples of Tongchang and Fujiawu ore-field, the authors found that δ13CPDB values of siderite were close to the δ13CPDB value of original magma; δ30Si values of the samples at the ore-forming stage were close to the δ30Si value range of magma, δ30Si values of partial samples were far away from it; Cu isotopic compositions of massive chalcopyrite formed at the early ore-forming stage are higher than that of veinal chalcopyrite formed at the later ore-forming stage. The results show that ore-forming materials were mainly derived from the porphyry body, and part of them were from wall rock materials.

  7. Process mineralogy of copper-nickel sulphide flotation by cyclonic-static micro-bubble flotation column

    Institute of Scientific and Technical Information of China (English)

    CAO Yi-jun; GUI Xia-hui; MA Zi-long; YU Xiao-xia; CHEN Xiao-dong; ZHANG Xiu-pin

    2009-01-01

    In our study we investigated a refractory copper-nickel sulfide ore separation by using a cyclonic-static micro-bubble flotation column (FCSMC). The process mineralogy of the main products was studied. Using a scanning electron micro-scope-energy dispersive system (SEM-EDS) and an X-ray spectrometer the mineral category and content of samples were analyzed. By using a mineral liberation analyzer (MLA) the mineral liberation characteristics were revealed. It is shown that in roughing feed the monomers liberation degree of nickel pyrite and chalcopyrite take up 84.11% and 88.82%, respectively. In tailings, the lost nickel pyrite and chalcopyrite are mainly monomers. Therefore, strengthening the micro-fine particle recovery capacity is the key to increase recovery.

  8. Structural and optical properties of homogeneous Cu(In,Ga)Se2 thin films prepared by thermal reaction of InSe/Cu/GaSe alloys with elemental Se vapour

    Science.gov (United States)

    Dejene, F. B.; Alberts, V.

    2005-01-01

    In this study, thin films of Cu(In,Ga)Se2 were prepared by the controlled reaction of thermally evaporated InSe/Cu/GaSe precursors with elemental Se vapour in vacuum. We indicate that this classical two-step growth process can be utilized to produce homogeneous single-phase chalcopyrite absorber films with superior structural properties. X-ray diffraction studies indicated that the interplanar spacing d(112) decreases linearly with an increase in the Ga/[In + Ga] atomic ratio due to homogeneous incorporation of gallium into the chalcopyrite lattice. Optical studies revealed the expected systematic increase in the band gap with increasing gallium concentration, once again confirming the monophasic nature of the alloys.

  9. Structural and optical properties of homogeneous Cu(In,Ga)Se{sub 2} thin films prepared by thermal reaction of InSe/Cu/GaSe alloys with elemental Se vapour

    Energy Technology Data Exchange (ETDEWEB)

    Dejene, F B; Alberts, V [Department of Physics, Rand Afrikaans University, PO Box 524, Johannesburg (South Africa)

    2005-01-07

    In this study, thin films of Cu(In,Ga)Se{sub 2} were prepared by the controlled reaction of thermally evaporated InSe/Cu/GaSe precursors with elemental Se vapour in vacuum. We indicate that this classical two-step growth process can be utilized to produce homogeneous single-phase chalcopyrite absorber films with superior structural properties. X-ray diffraction studies indicated that the interplanar spacing d{sub (112)} decreases linearly with an increase in the Ga/[In + Ga] atomic ratio due to homogeneous incorporation of gallium into the chalcopyrite lattice. Optical studies revealed the expected systematic increase in the band gap with increasing gallium concentration, once again confirming the monophasic nature of the alloys.

  10. Reliable wet-chemical cleaning of natively oxidized high-efficiency Cu(In,Ga)Se{sub 2} thin-film solar cell absorbers

    Energy Technology Data Exchange (ETDEWEB)

    Lehmann, Jascha [Renewable Energies, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Potsdam Institute for Climate Impact Research (PIK), 14473 Potsdam (Germany); Lehmann, Sebastian, E-mail: sebastian.lehmann@ftf.lth.se [Renewable Energies, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Solid State Physics, Lund University, Box 118, S-22100 Lund (Sweden); Lauermann, Iver; Rissom, Thorsten; Kaufmann, Christian A.; Lux-Steiner, Martha Ch. [Renewable Energies, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Bär, Marcus, E-mail: marcus.baer@helmholtz-berlin.de [Renewable Energies, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus-Senftenberg, Platz der Deutschen Einheit 1, 03046 Cottbus (Germany); Sadewasser, Sascha, E-mail: sascha.sadewasser@inl.int [Renewable Energies, Helmholtz-Zentrum Berlin für Materialien und Energie, Hahn-Meitner-Platz 1, 14109 Berlin (Germany); International Iberian Nanotechnology Laboratory, Av. Mestre José Veiga s/n, 4715-330 Braga (Portugal)

    2014-12-21

    Currently, Cu-containing chalcopyrite-based solar cells provide the highest conversion efficiencies among all thin-film photovoltaic (PV) technologies. They have reached efficiency values above 20%, the same performance level as multi-crystalline silicon-wafer technology that dominates the commercial PV market. Chalcopyrite thin-film heterostructures consist of a layer stack with a variety of interfaces between different materials. It is the chalcopyrite/buffer region (forming the p-n junction), which is of crucial importance and therefore frequently investigated using surface and interface science tools, such as photoelectron spectroscopy and scanning probe microscopy. To ensure comparability and validity of the results, a general preparation guide for “realistic” surfaces of polycrystalline chalcopyrite thin films is highly desirable. We present results on wet-chemical cleaning procedures of polycrystalline Cu(In{sub 1-x}Ga{sub x})Se{sub 2} thin films with an average x = [Ga]/([In] + [Ga]) = 0.29, which were exposed to ambient conditions for different times. The hence natively oxidized sample surfaces were etched in KCN- or NH{sub 3}-based aqueous solutions. By x-ray photoelectron spectroscopy, we find that the KCN treatment results in a chemical surface structure which is – apart from a slight change in surface composition – identical to a pristine as-received sample surface. Additionally, we discover a different oxidation behavior of In and Ga, in agreement with thermodynamic reference data, and we find indications for the segregation and removal of copper selenide surface phases from the polycrystalline material.

  11. Bioprocessing low grade copper ores - a promising alternative

    OpenAIRE

    Guezennec, Anne-Gwenaëlle; d'Hugues, Patrick

    2015-01-01

    International audience; This paper presents an overview of the work performed by the BRGM team in the last 10 years on the development of bio-hydrometallurgy dedicated to the processing of low-grade copper ores from the Kupferschiefer deposits. It covers selection and adaptation of microbial consortia, optimization of process operating parameters such as solid contents, the relationship between bioleaching performance and mineralogy, testing operating parameters to overcome chalcopyrite recal...

  12. Application of Raman Spectroscopy to the Biooxidation Analysis of Sulfide Minerals

    OpenAIRE

    J. V. García-Meza; R. H. Lara; Navarro-Contreras, H. R.

    2012-01-01

    We report the application of confocal laser scanning microscopy CLSM and Raman spectroscopy on the (bio)chemical oxidation of pyrite and chalcopyrite, in order to understand how surface sulfur species ( S 2 − / S 0 ) affects biofilm evolution during mineral colonization by Acidithiobacillus thiooxidans. We found that cells attachment occurs as cells clusters and monolayered biofilms within the first 12 h. Longer times resulted in the formation of micro- and macrocolonies with variable cell ...

  13. Structural and optical properties of electrodeposited culnSe{sub 2} thin films for photovoltaic solar cells; Propiedades estructurales y opticas de laminas delgadas de CulnSe2 electrodepositadas para su aplicacion en celulas solares fotovoltaicas

    Energy Technology Data Exchange (ETDEWEB)

    Guillen, C.; Herrero, J.; Galiano, F.

    1990-07-01

    Optical an structural properties of electrodeposited copper indium diselenide, CulnSe2, thin films were studied for its application in photovoltaic devices. X-ray diffraction patterns showed that thin films were grown in chalcopyrite phase after suitable treatments. Values of Eg for the CulnSe2 thin films showed a dependence on the deposition potential as determined by optical measurements. (Author) 47 refs.

  14. Density functional study of the structure, thermodynamics and electronic properties of CdGeAs{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Zapol, Peter; Pandey, Ravindra; Seel, Max [Department of Physics, Michigan Technological University, Houghton, MI 49931 (United States); Recio, J. Manuel [Departamento de Quimica Fisica y Analitica, Universidad de Oviedo, 33006-Oviedo (Spain); Ohmer, Melvin C. [Air Force Research Laboratory, Dayton, OH 45433 (United States)

    1999-06-14

    Structural, thermodynamic and electronic properties of CdGeAs{sub 2} with chalcopyrite structure are investigated in the framework of density functional theory. We employ the linear combination of atomic orbitals method with the Gaussian basis sets and present the results for the equation of state, the Grueneisen constant, the electronic band structure and the pressure coefficients of the valence and conduction levels in CdGeAs{sub 2}. (author)

  15. Mineralogical-Geochemical Peculiarities of Ores in Pyritaceous Fields of Filizchai Type in the Greater Caucasus

    Directory of Open Access Journals (Sweden)

    NOVRUZ A. NOVRUZOV

    2010-12-01

    Full Text Available Pyritaceous fields of the south slope of the Greater Caucasus confined to the Lower-Middle Jurassic sandy clayey deposits are: polygenic polychrone formations which were formed by a complex of hydrothermal sedimentary, hydrothermal metasomatic and hydrothermal metamorphogenic processes of ore formation. Filizchai pyritaceous polymetallic field is the largest in the region and can be characterized by diversity of texture-mineralogical types of ores, rich mineral composition and with geochemical spectrum. Some of the admixture components (Cd, In, Tl, Ga, Ge, Se, Hg are only in isomorphic forms in ores, others (Te, Bi, Au, Ag, Co, Sn, As along with it characterize in their own minerals. The Co is mainly concentrated in pyrite, pyrrhotine; Ag, Bi and also Te – in galenite and chalcopyrite; Se – in pyrite, pyrrhotine and galenite; in sphalerite (mainly in marmatite and chalcopyrite; Cd, Ga, Ge – in sphalerite, mainly in cleiophane; Au – in pyrite and chalcopyrite; Tl – in galenite and colloform pyrite. In all sulphides selenium prevails over tellurium (excepting the late chalcopyrite and cobalt over nickel. Maximum amount of cobalt is confined to pyrite from pyritaceous polymetallic ores and late generation of pyrrhotine. The nature of the connection between chemical elements in ores coordinates with determined stages of minerals formation. The main productive stage of ore formation bringing the main mass of gold, silver, rare and other precious components of ores are sulphosalt polymetallic stage of sulphur ploymetallic stage. Comparative analysis of absolute content of gold, silver and values of gold-silver relation in pyrite fields ores of region with appropriate values in meteorite standard indirectly indicates the relationship between gold-silver mineralization and assimilation crust source.

  16. Phase, morphology, and dimension control of CIS powders prepared using a solvothermal process

    Energy Technology Data Exchange (ETDEWEB)

    Chang, Chih-Hui [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China); Ting, Jyh-Ming, E-mail: jting@mail.ncku.edu.t [Department of Materials Science and Engineering, National Cheng Kung University, Tainan, Taiwan (China)

    2009-05-29

    Crystalline chalcopyrite semiconductor CuInSe{sub 2} nanostructures were prepared using a solvothermal route. Various amine organic agents were used as the solvents. Cupric chloride, indium chloride, and selenium powders were mixed in a solvent of ethylenediamine or diethylamine. Effects of reaction time, reaction temperature, solvent type, and reactant concentration were studied. The results show that through selective processing conditions, the phase, morphology, and dimensions of the obtained CIS nanostructures can be controlled.

  17. Métallurgie extractive protohistorique du cuivre :
    Etude thermodynamique et cinétique des réactions chimiques de transformation de minerais de cuivre sulfurés en métal et caractérisation des procédés

    OpenAIRE

    2008-01-01

    This PhD thesis is aimed at studying the two main steps of the copper extractive metallurgy processes starting from chalcopyrite (CuFeS2) : roasting and smelting for sheding light on an archeollogical problem. For each step, experimental simulations are performed at laboratory scale by modelizing the conditions of protohistoric furnaces. On one hand, kinetic of roasting is studied by thermogravimetry combined with the analysis of synthetic products. On the other hand, smelting simulations are...

  18. Investigation of the initial interface formation between CuInSe2 (112) and ZnO grown by ALD

    Energy Technology Data Exchange (ETDEWEB)

    Janocha, Eike; Pettenkofer, Christian [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany)

    2011-07-01

    The interface between a solar cell absorber and its transparent conductive oxide (TCO) defines the electrical properties and thus the efficiency of chalcopyrite solar cells. Since large conduction band offsets lower the solar cell photocurrent usually a CdS buffer layer is deposited by chemical bath deposition (CBD) between chalcopyrite absorber and TCO. Due to its toxicity and the interruption of the in-line production process by CBD an alternative buffer layer material would be advantageous. To improve the efficiencies of chalcopyrite solar cells a detailed understanding of the electronic band structure between absorber and TCO is necessary. Therefore, we investigated a model system of a single crystalline CuInSe2 absorber material grown in the technological important (112) orientation by molecular beam epitaxy and an epitaxial ZnO TCO grown layer-by-layer via atomic layer deposition (ALD). ALD is known for being a deposition technique allowing the growth of a single monolayer due to its self-limiting growth characteristics. In situ characterization of the initial growth has been performed after each ZnO deposition step by photoelectron spectroscopies (XPS/UPS/SR-PES) in an UHV growth and analysis system resulting in a detailed view of the interface formation and binding characteristics of the involved elements.

  19. First insights on the molybdenum-copper Bled M'Dena complex (Eglab massif, Algeria)

    Science.gov (United States)

    Lagraa, Karima; Salvi, Stefano; Béziat, Didier; Debat, Pierre; Kolli, Omar

    2017-03-01

    Molybdenum-Copper showings in the Eglab massif (eastern part of the Reguibat rise of Algeria), are found in quartz-monzodiorite and granodiorite of the Bled M'Dena complex, a Paleoproterozoic circular structure of ∼5 km in diameter, comprising volcanic and intrusive suites. The latter consist of quartz-diorite, quartz-monzodiorite and granodiorite with a metaluminous normative composition. They display an "adakitic character" with moderate light rare-earth element (LREE) enrichment, minor Eu anomalies, high Sr/Y ratio and low Yb concentration, suggestive of a hydrous, arc magma of volcanic-arc affinity. The mineralization occurs mostly in quartz + molybdenite + chalcopyrite stockwork veins marked by widespread propylitic alteration along the selvages. Molybdenite and chalcopyrite are commonly associated with calcite, which precipitated at relatively late stages of the hydrothermal alteration. Fluid inclusions related to the mineralization stage, range from aqueous to aqueous-carbonic to solid bearing. The latter inclusions have the highest homogenization temperature (up to ∼400 °C), are salt saturated, and commonly contain molybdenite and/or chalcopyrite crystals. The petrology and geochemistry of the host rocks, the style of the hydrothermal alteration, the ore mineral associations, and the characteristics of the fluid inclusions, are all coherent in indicating that the Bled M'Dena represents a Paleoproterozoic porphyry style Mo mineralization, which is far unreported in the African continent.

  20. Production method of thin film solar cell; Hakumaku taiyo denchi no seizo hoho

    Energy Technology Data Exchange (ETDEWEB)

    Oki, K.; Watanabe, T.; Matsui, M.

    1996-01-23

    This invention relates to the film formation of chalcopyrite type compound semiconductor used for thin film solar cell. In the case of CuInS2 thin film, heteromorphic phases such as CuIn5S8, Cu2S, and In2S3 are formed on the top surface together with the CuInS2 phase, resulting in the decrease in junction property when n-type semiconductor layer such as CdS layer is formed on it. According to the invention, p-type semiconductor layer made of chalcopyrite type compound semiconductor is dipped into an ammonia water before being laminated with n-type semiconductor layer. Although higher concentration and higher temperature of the ammonia water accelerates the heteromorphic phase film removal velocity, it also gives rise to higher evaporation rate of ammonia. The preferable concentration and temperature are, therefore, 0.01 - 50% and 5 - 80{degree}C, respectively. In this way, the chalcopyrite type compound semiconductor thin film free from heteromorphic phases on its surface can be produced. The thin film solar cell produced by using such thin film has a high conversion efficiency because of a good junction property with n-type semiconductor. 1 fig.

  1. Electrodeposition of Mg doped ZnO thin film for the window layer of CIGS solar cell

    Science.gov (United States)

    Wang, Mang; Yi, Jie; Yang, Sui; Cao, Zhou; Huang, Xiaopan; Li, Yuanhong; Li, Hongxing; Zhong, Jianxin

    2016-09-01

    Mg doped ZnO (ZMO) film with the tunable bandgap can adjust the conduction band offset of the window/chalcopyrite absorber heterointerface to positive to reduce the interface recombination and resulting in an increasement of chalcopyrite based solar cell efficiency. A systematic study of the effect of the electrodeposition potential on morphology, crystalline structure, crystallographic orientation and optical properties of ZMO films was investigated. It is interestingly found that the prepared doped samples undergo a significant morphological change induced by the deposition potential. With negative shift of deposition potential, an obvious morphology evolution from nanorod structrue to particle covered films was observed. A possible growth mechanism for explaining the morphological change is proposed and briefly discussed. The combined optical techniques including absorption, transmission and photoluminescence were used to study the obtained ZMO films deposited at different potential. The sample deposited at -0.9 V with the hexagonal nanorods morphology shows the highest optical transparency of 92%. The photoluminescence spectra reveal that the crystallization of the hexagonal nanorod ZMO thin film deoposited at -0.9 V is much better than the particles covered ZMO thin film. Combining the structural and optical properties analysis, the obtained normal hexagonal nanorod ZMO thin film could potentially be useful in nanostructured chalcopyrite solar cells to improve the device performance.

  2. The role of the spray pyrolysed Al2O3 barrier layer in achieving high efficiency solar cells on flexible steel substrates

    Science.gov (United States)

    Gledhill, Sophie E.; Zykov, Anton; Rissom, Thorsten; Caballero, Raquel; Kaufmann, Christian A.; Fischer, Christian-Herbert; Lux-Steiner, Martha; Efimova, Varvara; Hoffmann, Volker; Oswald, Steffen

    2011-07-01

    Thin film chalcopyrite solar cells grown on light-weight, flexible steel substrates are poised to enter the photovoltaic market. To guarantee good solar cell performance, the diffusion of iron from the steel into the CIGSe absorber material must be hindered during layer deposition. A barrier layer is thus required to isolate the solar module from the metal substrate, both electronically and chemically. Ideally the barrier layer would be deposited by a cheap roll-to-roll process suitable to coat flexible steel substrates. Aluminium oxide deposited by spray pyrolysis matches the criteria. The coating is homogeneous over rough substrates allowing comparatively thin barrier layers to be utilized. In this article, solar cell results are presented contrasting the device performance made with a barrier layer to that without a barrier layer. Secondary Ion Mass spectrometry (SIMS) measurements show that the spray pyrolysed barrier layer diminishes iron diffusion to the chalcopyrite absorber layer. The role of sodium, imperative for the growth of high efficiency chalcopyrite solar cells, and how it interacts with Al2O3 is discussed.

  3. Structure and composition of Zn(x)Cd(1-xS) films synthesized through chemical bath deposition.

    Science.gov (United States)

    Tosun, B Selin; Pettit, Chelsea; Campbell, Stephen A; Aydil, Eray S

    2012-07-25

    Zinc cadmium sulfide (ZnxCd1-xS) thin films grown through chemical bath deposition are used in chalcopyrite solar cells as the buffer layer between the n-type zinc oxide and the p-type light absorbing chalcopyrite film. To optimize energetic band alignment and optical absorption, advanced solar cell architectures require the ability to manipulate x as a function of distance from the absorber-ZnCdS interface. Herein, we investigate the fundamental factors that govern the evolution of the composition as a function of depth in the film. By changing the initial concentrations of Zn and Cd salts in the bath, the entire range of overall compositions ranging from primarily cubic ZnS to primarily hexagonal CdS could be deposited. However, films are inhomogeneous and x varies significantly as function of distance from the film-substrate interface. Films with high overall Zn concentration (x > 0.5) exhibit a Cd-rich layer near the film-substrate interface because Cd is more reactive than Zn. This layer is typically beneath a nearly pure ZnS film that forms after the Cd-rich layers are deposited and Cd is depleted in the bath. In films with high overall Cd concentration (x < 0.5) the Zn concentration rises towards the film's surface. Fortunately, these gradients are favorable for solar cells based on low band gap chalcopyrite films.

  4. Platinum-group element concentrations in pyrite from the Main Sulfide Zone of the Great Dyke of Zimbabwe

    Science.gov (United States)

    Piña, R.; Gervilla, F.; Barnes, S.-J.; Oberthür, T.; Lunar, R.

    2016-10-01

    The Main Sulfide Zone (MSZ) of the Great Dyke of Zimbabwe hosts the world's second largest resource of platinum-group elements (PGE) after the Bushveld Complex in South Africa. The sulfide assemblage of the MSZ comprises pyrrhotite, pentlandite, chalcopyrite, and minor pyrite. Recently, several studies have observed in a number of Ni-Cu-PGE ore deposits that pyrite may host significant amounts of PGE, particularly Pt and Rh. In this study, we have determined PGE and other trace element contents in pyrite from the Hartley, Ngezi, Unki, and Mimosa mines of the Great Dyke by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS). Based on the textures and PGE contents, two types of pyrite can be differentiated. Py1 occurs as individual euhedral or subhedral grains or clusters of crystals mostly within chalcopyrite and pentlandite, in some cases in the form of symplectitic intergrowths, and is PGE rich (up to 99 ppm Pt and 61 ppm Rh; 1.7 to 47.1 ppm Ru, 0.1 to 7.8 ppm Os, and 1.2 to 20.2 ppm Ir). Py2 occurs as small individual euhedral or subhedral crystals within pyrrhotite, pentlandite, and less frequently within chalcopyrite and silicates and has low PGE contents (<0.11 ppm Pt, <0.34 ppm Rh, <2.5 ppm Ru, <0.37 ppm Ir, and <0.40 ppm Os). Py1 contains higher Os, Ir, Ru, Rh, and Pt contents than the associated pyrrhotite, pentlandite, and chalcopyrite, whereas Py2 has similar PGE contents as coexisting pyrrhotite and pentlandite. Based on the textural relationships, two different origins are attributed for each pyrite type. Py1 intergrowth with pentlandite and chalcopyrite is inferred to have formed by late, low temperature (<300 °C) decomposition of residual Ni-rich monosulfide solid solution, whereas Py2 is suggested to have formed by replacement of pyrrhotite and pentlandite caused by late magmatic/hydrothermal fluids.

  5. Petrography, sulfide mineral chemistry, and sulfur isotope evidence for a hydrothermal imprint on Musina copper deposits, Limpopo Province, South Africa: Evidence for a breccia pipe origin?

    Science.gov (United States)

    Chaumba, Jeff B.; Mundalamo, Humbulani R.; Ogola, Jason S.; Cox, J. A.; Fleisher, C. J.

    2016-08-01

    The Musina copper deposits are located in the Central Zone of the Limpopo orogenic belt in Limpopo Province, South Africa. We carried out a petrographic, sulfide composition, and δ34S study on samples from Artonvilla and Campbell copper deposits and a country rock granitic gneiss to Artonvilla Mine to place some constrains on the origin of these deposits. The assemblages at both Artonvilla and Campbell Mines of brecciated quartz, potassium feldspar, muscovite, chlorite, calcite, and amphibole are consistent with sericitic alteration. Quartz, amphibole, feldspars, and micas often display angular textures which are consistent with breccias. Sulfur concentrations in pyrite from Artonvilla Mine plot in a narrow range, from 50.2 wt. % to 55.7 wt. %. With the exception of a positive correlation between Fe and Cu, no well defined correlations are shown by data from the Musina copper deposits. The occurrence of sulfides both as inclusions in, or as interstitial phases in silicates, suggests that hydrothermal alteration that affected these deposits most likely helped concentrate the mineralization at the Musina copper deposits. Sulfur concentrations in chalcopyrite samples investigated vary widely whereas the copper concentrations in chalcopyrite are not unusually higher compared to those from chalcopyrite from other tectonic settings, probably indicating that either the Cu in the Musina copper deposits occurs in native form, and/or that it is hosted by other phases. This observation lends support to the Cu having been concentrated during a later hydrothermal event. One sample from Artonvilla Mine (AtCal01) yielded pyrite δ34S values of 3.1and 3.6‰ and chalcopyrite from the same sample yielded a value of 3.9‰. A country rock granitic gneiss to Artonvilla Mine yielded a δ34Spyrite value of 8.2‰. For Campbell Mine samples, one quartz vein sample has a δ34Spyrite value of 0.5‰ whereas chalcopyrite samples drilled from different areas within the same sample yielded

  6. Control of gallium incorporation in sol–gel derived CuIn{sub (1−x)}Ga{sub x}S{sub 2} thin films for photovoltaic applications

    Energy Technology Data Exchange (ETDEWEB)

    Bourlier, Yoan [Institut de Recherche sur les Composants logiciels et matériels pour l’Information et la Communication Avancée (IRCICA), CNRS USR 3380, Université Lille 1, 50 avenue Halley, 59655 Villeneuve d’Ascq CEDEX (France); Cristini Robbe, Odile [Institut de Recherche sur les Composants logiciels et matériels pour l’Information et la Communication Avancée (IRCICA), CNRS USR 3380, Université Lille 1, 50 avenue Halley, 59655 Villeneuve d’Ascq CEDEX (France); Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS UMR 8523, Université Lille, 59655 Villeneuve d’Ascq CEDEX (France); Lethien, Christophe [Institut de Recherche sur les Composants logiciels et matériels pour l’Information et la Communication Avancée (IRCICA), CNRS USR 3380, Université Lille 1, 50 avenue Halley, 59655 Villeneuve d’Ascq CEDEX (France); Laboratoire de Physique des Lasers, Atomes et Molécules (PhLAM), CNRS UMR 8523, Université Lille, 59655 Villeneuve d’Ascq CEDEX (France); Institut d’Electronique, de Microélectronique et de Nanotechnologie (IEMN), CNRS UMR 8520, Avenue Poincaré, 59652 Villeneuve d’Ascq CEDEX (France); and others

    2015-10-15

    Highlights: • CuIn{sub (1−x)}Ga{sub x}S{sub 2} thin films were prepared by sol–gel process. • Evolution of lattice parameters is characteristic of a solid solution. • Optical band gap was found to be linearly dependent on the gallium rate. - Abstract: In this paper, we report the elaboration of Cu(In,Ga)S{sub 2} chalcopyrite thin films via a sol–gel process. To reach this aim, solutions containing copper, indium and gallium complexes were prepared. These solutions were thereafter spin-coated onto the soda lime glass substrates and calcined, leading to metallic oxides thin films. Expected chalcopyrite films were finally obtained by sulfurization of oxides layers using a sulfur atmosphere at 500 °C. The rate of gallium incorporation was studied both at the solutions synthesis step and at the thin films sulfurization process. Elemental and X-ray diffraction (XRD) analyses have shown the efficiency of monoethanolamine used as a complexing agent for the preparation of CuIn{sub (1−x)}Ga{sub x}S{sub 2} thin layers. Moreover, the replacement of diethanolamine by monoethanolamine has permitted the substitution of indium by isovalent gallium from x = 0 to x = 0.4 and prevented the precipitation of copper derivatives. XRD analyses of sulfurized thin films CuIn{sub (1−x)}Ga{sub x}S{sub 2,} clearly indicated that the increasing rate of gallium induced a shift of XRD peaks, revealing an evolution of the lattice parameter in the chalcopyrite structure. These results were confirmed by Raman analyses. Moreover, the optical band gap was also found to be linearly dependent upon the gallium rate incorporated within the thin films: it varies from 1.47 eV for x = 0 to 1.63 eV for x = 0.4.

  7. Soft X-rays shedding light on thin-film solar cell surfaces and interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Bär, M., E-mail: marcus.baer@helmholtz-berlin.de [Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin (Germany); Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus, D-03046 Cottbus (Germany); Department of Chemistry, University of Nevada, Las Vegas (UNLV), Las Vegas, NV 89154 (United States); Pookpanratana, S. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), Las Vegas, NV 89154 (United States); Weinhardt, L. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), Las Vegas, NV 89154 (United States); Institute for Photon Science and Synchrotron Radiation, Karlsruhe Institute of Technology (KIT), D-76344 Eggenstein-Leopoldshafen (Germany); ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology, D-76344 Eggenstein-Leopoldshafen (Germany); Wilks, R.G.; Schubert, B.A.; Marsen, B.; Unold, T. [Solar Energy Research, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH (HZB), D-14109 Berlin (Germany); Blum, M.; Krause, S. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), Las Vegas, NV 89154 (United States); Zhang, Y. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), Las Vegas, NV 89154 (United States); Department of Physics, Xiamen University, Xiamen, Fujian 361005 (China); Ranasinghe, A. [Department of Chemistry, University of Nevada, Las Vegas (UNLV), Las Vegas, NV 89154 (United States); Ramanathan, K.; Repins, I.; Contreras, M.A. [National Renewable Energy Laboratory (NREL), Golden, CO 80401 (United States); Nishiwaki, S. [Institute for Energy Conversion (IEC), University of Delaware, Newark, DE 19716 (United States); and others

    2013-10-15

    Highlights: ► S/Se gradient-driven chemical interaction at the CdS/CIG(S)Se interface. ► Depth-dependent band gap in chalcopyrites. ► Band alignment at the CdS/Cu{sub 2}ZnSnS{sub 4} solar cell heterojunction. ► Post-deposition treatment induces intermixing in the CdTe/CdS solar cell structure. -- Abstract: Thin-film solar cells based on compound semiconductors consist of a multilayer structure with various interfaces and contain a multitude of elements and impurities, etc. A rapid progress of these photovoltaic technologies can only be achieved by an insight-driven optimization/development. Hence it is crucial to characterize and understand the relationship between the chemical and electronic properties of these components. This paper reviews some examples of our recent work characterizing compound semiconductor thin films using laboratory- and synchrotron-based electron and soft X-ray spectroscopic characterization methods. It is demonstrated how these different analytical techniques are extraordinarily powerful to reveal the material characteristics from many different perspectives, ultimately resulting in a comprehensive picture of the related electronic and chemical properties. As examples, the paper will discuss the electronic surface structure of chalcopyrite thin-film solar cell absorbers, the chemical structure of the CdS/chalcopyrite interface, present the band alignment at the CdS/kesterite interface, and report on how post-deposition treatments cause chemical interaction/interdiffusion processes in CdTe/CdS thin-film solar cell structures.

  8. Geological and geochemical studies of the Shujiadian porphyry Cu deposit, Anhui Province, Eastern China: Implications for ore genesis

    Science.gov (United States)

    Wang, Shiwei; Zhou, Taofa; Yuan, Feng; Fan, Yu; White, Noel C.; Lin, Fengjie

    2015-05-01

    Most porphyry deposits in the world occur in magmatic arc settings and are related to subduction of oceanic plates. A small proportion of porphyry deposits occur in intracontinental settings, however they are still poorly understood. Shujiadian, a newly-discovered porphyry Cu deposit, is located in the Middle-Lower Yangtze River Valley metallogenic belt and belongs to the intracontinental class. The deposit has classic alteration zones defined by a core of potassic alteration and local Ca-silicate alteration, which is overprinted by a feldspar-destructive alteration zone and cut by veins containing epidote and chlorite. Wallrocks of the deposit are unreactive quartz-rich sedimentary rocks. Three main paragenetic stages have been recognized based on petrographic observations; silicate stage, quartz-sulfide stage, and sulfide-carbonate stage. Quartz + pyrite + chalcopyrite ± molybdenite veins, and quartz + chalcopyrite + pyrite veins of the quartz-sulfide stage contribute most of the copper, and chalcopyrite + chlorite ± pyrite ± pyrrhotite ± quartz ± illite veins of the sulfide-carbonate stage also contribute part of the copper; all the mineralized veins are associated with feldspar-destructive alteration. Investigations on the fluid inclusions in Shujiadian indicate that the ore-forming fluids had four evolutionary episodes: immiscibility and overpressure in the silicate stage, boiling in the quartz-sulfide stage and mixing with meteoric water in the sulfide-carbonate stage. Sulfur and strontium isotope studies suggest that ore metals were mainly derived from magmatic-hydrothermal fluids, and combined with our study of fluid inclusions, we infer that decompression, changes in oxygen fugacity and sulfur content were the main factors that caused Cu precipitation. Compared with porphyry deposits in magmatic arc settings, there are some differences in the ore-bearing rock, alteration, and the composition of ore-forming fluids.

  9. Petrogeochemistry of listvenite association in metaophiolites of Sahlabad region, eastern Iran: Implications for possible epigenetic Cu-Au ore exploration in metaophiolites

    Science.gov (United States)

    Aftabi, Alijan; Zarrinkoub, Mohammad Hossien

    2013-01-01

    Petrogeochemical investigations at the Sahlabad region have revealed that epigenetic listvenite veins occur in sheared zones of metaophiolitic suites of Cretaceous age. The listvenite mineralization developed in three forms, namely (1) the silica-listvenite veins which are chiefly composed of chalcedony, opal, quartz, pyrite, chalcopyrite, serpentine and relicts of chrome spinels, magnetite and fuchsite; (2) the carbonate listvenite veins which are comprised principally of magnesite, dolomite, calcite, siderite, pyrite, chalcopyrite, serpentine and relicts of fuchsite, chrome spinels and magnetite; and (3) the silica-carbonate listvenite veins which include opal, quartz, dolomite, magnesite, pyrite, chalcopyrite, serpentine and relicts of chrome spinels and magnetite. The absence of mineralized granitoids and the frequent occurrences of clearcut non-metamorphosed veins indicate that the mineralizing fluids were rich in CO2, H2O, H2S and H4SiO4 and possibly formed as a result of metamorphic dehydration and decarbonation reactions of the oceanic crust at the amphibolite-greenschist facies. Geochemically, the listvenites are enriched in SiO2, MgO, CaO, CO2, LOI, Cr, Ni, Co, Au, Cu, Ag, Hg, and Pt. Also, the veins contain high values of LOI, indicating the H2O-CO2-rich metamorphogenic fluids. The high Cr content and detectable values of K2O, Al2O3 and Na2O in the listvenite veins possibly indicate the presence of fuchsite and chrome spinels. The geochemical signatures attest that the hydrothermal fluids probably derived from a metamorphosed ultramafic protolith. The maximum values for gold, copper, mercury and silver in the listvenites are about 1.9 ppm, 5.4 %, 8 ppm and 6.5 ppm, respectively and provide a unique exploration guide for further gossan sampling, remote sensing mapping, isotopic and fluid inclusion studies in the Iranian metaophiolites.

  10. One-step electrodeposition process of CuInSe2: Deposition time effect

    Indian Academy of Sciences (India)

    O Meglali; N Attaf; A Bouraiou; M S Aida; S Lakehal

    2014-10-01

    CuInSe2 thin films were prepared by one-step electrodeposition process using a simplified twoelectrodes system. The films were deposited, during 5, 10, 15 and 20 min, from the deionized water solution consisting of CuCl2, InCl3 and SeO2 onto ITO-coated glass substrates. As-deposited films have been annealed under vacuum at 300 °C during 30 min. The structural, optical band gap and electrical resistivity of elaborated films were studied, respectively, using X-ray diffraction (XRD), Raman spectroscopy, UV spectrophotometer and four-point probe method. The micro structural parameters like lattice constants, crystallite size, dislocation density and strain have been evaluated. The XRD investigation proved that the film deposited at 20 min present CuInSe2 single phase in its chalcopyrite structure and with preferred orientation along (1 1 2) direction, whereas the films deposited at 5, 10 and 15 min show the CuInSe2 chalcopyrite structure with the In2Se3 as secondary phase. We have found that the formation mechanism of CuInSe2 depends on the In2Se3 phase. The optical band gap of the films is found to decrease from 1.17 to 1.04 eV with increase in deposition time. All films show Raman spectra with a dominant A1 mode at 174 cm-1, confirming the chalcopyrite crystalline quality of these films. The films exhibited a range of resistivity varying from 2.3 × 10-3 to 4.4 × 10-1 cm.

  11. Proton microprobe study of tin-polymetallic deposits

    Energy Technology Data Exchange (ETDEWEB)

    Murao, S. [Geological Survey of Japan, Tsukuba, Ibaraki (Japan); Sie, S.H.; Suter, G.F. [Commonwealth Scientific and Industrial Research Organisation (CSIRO), North Ryde, NSW (Australia). Div. of Exploration Geoscience

    1996-12-31

    Tin-polymetallic vein type deposits are a complex mixture of cassiterite and sulfides and they are the main source of technologically important rare metals such as indium and bismuth. Constituent minerals are usually fine grained having wide range of chemical composition and often the elements of interest occur as trace elements not amenable to electron microprobe analysis. PIXE with a proton microprobe can be an effective tool to study such deposits by delineating the distribution of trace elements among carrier minerals. Two representative indium-bearing deposits of tin- polymetallic type, Tosham of India (Cu-ln-Bi-Sn-W-Ag), and Mount Pleasant of Canada (Zn-Cu-In-Bi-Sn-W), were studied to delineate the distribution of medical/high-tech rare metals and to examine the effectiveness of the proton probe analysis of such ore. One of the results of the study indicated that indium and bismuth are present in chalcopyrite in the deposits. In addition to these important rare metals, zinc, copper, arsenic, antimony, selenium, and tin are common in chalcopyrite and pyrite. Arsenopyrite contains nickel, copper, zinc, silver, tin, antimony and bismuth. In chalcopyrite and pyrite, zinc, arsenic, indium, bismuth and lead are richer in Mount Pleasant ore, but silver is higher at Tosham. Also thallium and gold were found only in Tosham pyrite. The Tosham deposit is related to S-type granite, while Mount Pleasant to A-type. It appears that petrographic character of the source magma is one of the factors to determine the trace element distribution in tin-polymetallic deposit. 6 refs., 2 figs.

  12. Composition at the CuInSe{sub 2}/ZnO interface: Copper depletion induced by diethyl-zinc

    Energy Technology Data Exchange (ETDEWEB)

    Hofmann, A.; Janocha, E.; Kelleter, F.; Pettenkofer, C. [Helmholtz-Zentrum-Berlin, Institute for Silicon Photovoltaics, Albert-Einstein-Str. 15, 12489, Berlin (Germany)

    2014-09-15

    The interface formation between epitaxial CuInSe{sub 2}(112) films and ZnO deposited by metal-organic MBE is investigated by photoelectron spectroscopy. Reaction of diethyl-zinc with CuInSe{sub 2} leads to the formation of an intrinsic ZnSe layer and copper depletion of the interface. This is associated with Zn doping of the chalcopyrite surface and a Fermi-level shift toward the conduction band. The implications on the band alignment are discussed. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  13. Photoconductive Properties of Brush Plated Copper Indium Gallium Selenide Films

    OpenAIRE

    Subiramaniyam, N. P.; P. Thirunavukkarasu; Murali, K. R.

    2013-01-01

    Copper indium gallium selenide (CIGS) films were deposited for the first time by the brush electrodeposition technique. X-ray diffraction studies indicated the formation of single phase chalcopyrite CIGS. Lattice parameters, dislocation density, and strain were calculated. Band gap of the films increased from 1.12 eV to 1.63 eV as the gallium concentration increased. Room temperature transport parameters of the films, namely, resistivity increased from 0.10 ohm cm to 12 ohm cm, mobility decre...

  14. Disseminated sulphides in basalts from the northern central Indian ridge: Implications on late-stage hydrothermal activity

    Digital Repository Service at National Institute of Oceanography (India)

    Banerjee, R.; Ray, D.

    °N; Beltenev et al. 2003), 13°30′N MAR (Beltenev et al. 2007), Nibelzen (8°18′S; Melchert et al. 2008), 14°45′N Logatchev (Batuev et al. 1994), Saldanha (36°34′N) and Menez Hom (37°8′N; Marques et al. 2007). Compared to substantial investigations... (range 45.21–47.26 wt%). Skeletal amorphous-type pyrite grains have moderate Co contents (avg. up to 0.66 wt%), whereas euhedral pyrites have the lowest Co contents (avg. up to 0.14 wt%). Chalcopyrite mainly shows bimodal associations: (1) sep- arate...

  15. The Effect of Sulfur Fugacity on Pt, Pd and Au in Magmatic-Hydrothermal Systems

    Science.gov (United States)

    Bell, A.; Simon, A.

    2009-05-01

    We have constrained experimentally the effect of sulfur fugacity (fS2) and sulfide saturation on the fractionation and partitioning behavior of Pt, Pd and Au in a felsic silicate melt + sulfide crystal/melt + oxide + supercritical aqueous fluid phase + Pt + Pd + Au system. Experiments were performed at 800°C, 150 MPa, with oxygen fugacity (fO2) fixed at approximately the nickel + nickel oxide buffer (NNO). Sulfur fugacity in the experiments was varied five orders of magnitude from approximately logfS2 = 0 to logfS2 = -5 by using two different sulfide phase assemblages. Sulfide assemblage one consisted initially of chalcopyrite plus pyrrhotite and assemblage two consisted of chalcopyrite plus bornite. At run conditions, in both assemblages, pyrrhotite transformed compositionally to monosulfide solid solution (mss), chalcopyrite to intermediate solid solution (Iss), and in assemblage two chalcopyrite and bornite formed a sulfide melt. Run- product silicate glass (i.e., quenched silicate melt) and crystalline materials were analyzed by using both electron probe microanalysis (EPMA) for major elements and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) for major and trace elements. The measured concentrations of Pt, Pd, and Au in quenched silicate melt in runs with logfS2 values ranging from approximately 0 to -5, do not exhibit any apparent dependence on the dissolved sulfur content of the melt. The measured Pt, Pd and Au concentrations in mss vary as a function of fS2. The measured Pt, Pd and Au concentrations in Iss do not appear to be dependent on fS2. The system variables fS2 and fO2, working in concert with each other, control the stable magmatic sulfide phase assemblage. Additionally, the system fS2 strongly influences the solubility of Pt, Pd, and Au as lattice bound components in some common crystalline magmatic sulfide phases. Both the stable magmatic sulfide phase assemblage and the solubility of Pt, Pd, and Au as constituents in

  16. 东川落雪铜矿床地质特征及成因研究%Geological characteristics and prospecting direction of copper deposit in Luoxue, Dongchuan, China

    Institute of Scientific and Technical Information of China (English)

    卢桂梅; 金廷福; 胡永亮

    2016-01-01

    矿床中,铁、铜矿体主要赋存于落雪组碳酸盐岩地层,矿石矿物主要为黄铜矿、赤铁矿,它形-半自形结构,块状、浸染状、角砾状等构造。沿构造和地层薄弱带贯入形成。%Iron, copper orebodies mainly occur in carbonate rocks of Luoxue formation. Ore minerals are mainly chalcopyrite, he-matite, which has forms-semi-shaped structure, massive, disseminated, brecciated, vein-like structure and so on.

  17. Wood textures in Jinman copper deposit in western Yunnan and their genetic implications

    Institute of Scientific and Technical Information of China (English)

    刘家军; 李朝阳; 张乾; 潘家永; 刘玉平; 刘显凡; 刘世荣; 杨伟光

    2001-01-01

    Jinman vein copper deposit in western Yunnan occurs in a salt-bearing red clastic rock formation composed of sandstone, siltstone and shale. Wood texture is considerably developed in the ores. The metallic minerals making up the wood textures mainly include pyrite, chalcopyrite and bornite. Studies on the samples and examination of their micrographs and electron micrographs have confirmed that they belong to xenoxylon, reflecting that the ore-hosting rock series is the product of sedimentation in the terrestrial environment. Organic geochemistry and sulfur and carbon isotopic composition data indicate that the formation of the deposit is substantially related with underground hot brines and biological processes.

  18. Thermal Decomposition Based Synthesis of Ag-In-S/ZnS Quantum Dots and Their Chlorotoxin-Modified Micelles for Brain Tumor Cell Targeting

    OpenAIRE

    Chen, Siqi; Ahmadiantehrani, Mojtaba; Publicover, Nelson G.; Hunter, Kenneth W.; Zhu, Xiaoshan

    2015-01-01

    Cadmium-free silver-indium-sulfide (Ag-In-S or AIS) chalcopyrite quantum dots (QDs) as well as their core-shell structures (AIS/ZnS QDs) are being paid significant attention in biomedical applications because of their low toxicity and excellent optical properties. Here we report a simple and safe synthetic system to prepare high quality AIS and AIS/ZnS QDs using thermal decomposition. The synthetic system simply involves heating a mixture of silver acetate, indium acetate, and oleic acid in d...

  19. Selenium, tellurium and precious metal mineralogy in Uchalinsk copper-zinc-pyritic district, the Urals

    Science.gov (United States)

    Vikentev, I.

    2016-04-01

    During processing the most of Au, Ag, Se, Te, Pb, Bi, Sb, Hg as well as notable part of Cu, Zn and Cd fail for tailings and became heavy metal pollutants. Modes of occurrence of Au, Ag, Te and Se covers two giant VMS deposits: Uchaly (intensively deformed) and Uzelginsk (altered by late hydrothermal processes) as well as middle-sized Molodezn and West Ozern deposits (nondeformed) have been studied. Mineral forms of these elements as well as their presence in disperse mode in common ore minerals (pyrite, chalcopyrite, sphalerite) have been studied using SEM, EPMA, INAA, ICP-MS and LA-ICP-MS.

  20. Preparation and characterization of Zn Se thin films

    CERN Document Server

    Ganchev, M; Stratieva, N; Gremenok, V; Zaretskaya, E; Goncharova, O

    2003-01-01

    Chemical bath deposition technique for preparation of ZnSe thin films is presented. The influence of bath temperature and duration of deposition on film growth and quality has been studied. The effect of post-deposition annealing in different ambient is also discussed. It has been determined that heat treatment removes the oxygen-containing phase from the as-deposited films and improves crystallinity. The optical and electric properties of the deposits show their potential for an alternative buffer layer in chalcopyrite-based solar cells.

  1. Growth and characterization of CuIn{sub x}Ga{sub 1-x}Te{sub 2} used for photovoltaic conversion

    Energy Technology Data Exchange (ETDEWEB)

    Benabdeslem, M.; Bechiri, L.; Benslim, N.; Mahdjoubi, L.; Hannech, E.B.; Zouiti, M. [Laboratoire des Surfaces et Interfaces (LSIMS), Universite d' Annaba (Algerie) (France); Nouet, G. [CRISMAT-ISMRA, Universite, 6-Boulevard du Marechal Juin, 14050 Caen (France)

    2006-02-15

    Bulk and thin films of CuIn{sub 0.75}Ga{sub 0.25}Te{sub 2} have been grown using respectively the sealed quartz ampoule and the flash evaporation techniques. X-ray diffraction results showed that the semiconductor has the chalcopyrite structure. The gaps of the materials were determined from optical measurements and found to be 0.99 and 1.14eV, respectively for bulk and annealed films. Photoluminescence data showed a broad emission localised at 1.05eV. (author)

  2. ホットプレス法により作製したCuInTe2の成長温度依存性

    OpenAIRE

    田代, 龍一; 吉野, 賢二; 碇, 哲雄

    2011-01-01

    Undoped CuInTe2 crystals were grown by hot-press (HP) method at 400 ~ 700℃ for 1 h under high pressure (10 ~ 40 MPa). One of the advantages of the HP method is that a crystal growth is easy at low temperature. The sizes of the samples were 20 mm in diameter. All samples indicated chalcopyrite structures, nearly stoichiometry and p-type by means of X-ray diffraction, electron probe microanalysis and thermoprobe analysis, respectively. However, the sample grown at 400℃ had a secondary phase. Ac...

  3. Electronic and optical properties of CuInTe2

    Science.gov (United States)

    Shankar, A.; Thapa, R. K.; Mandal, P. K.

    2016-10-01

    The electronic and optical properties of a ternary chalcopyrite compound CuInTe2 with diamond like structure have been studied. The calculations are carried out using the density functional theory (DFT) based full potential-linearized augmented plane wave (FP- LAPW) method within the framework of GGA and modified Becke Johnson (mBJ) potential approach. The presence of direct energy band gap of 0.8 eV suggests the sample material can be a good material for solar cell application. The study of the optical response of the material against the incident photon energy radiation indicates the material can be an effective candidate for the optoelectronic devices.

  4. Studies on Environmentally Friendly Leaching Processes in China

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The newly developed green leaching processes for chromium, lead and gold extraction from ores or concentrates are described. The chromium is extracted from the iron chromite ore with fused sodium hydroxide at 500-550°C as sodium chromate. The galena in lead sulfide concentrate is converted into lead carbonate in ammonium or sodium carbonate solution at 50-80°C followed by the separation of lead carbonate formed from the unconverted sulfide ores by flotation. Gold associated with sulfide ore (such as pyrite and chalcopyrite) can be extracted into sodium thiosulfate solution without any pretreatment such as roasting, high pressure aqueous oxidation or bacteria pre-leaching.

  5. Chemically deposited In2S3-Ag2S layers to obtain AgInS2 thin films by thermal annealing

    Science.gov (United States)

    Lugo, S.; Peña, Y.; Calixto-Rodriguez, M.; López-Mata, C.; Ramón, M. L.; Gómez, I.; Acosta, A.

    2012-12-01

    AgInS2 thin films were obtained by the annealing of chemical bath deposited In2S3-Ag2S layers at 400 °C in N2 for 1 h. According to the XRD and EDX results the chalcopyrite structure of AgInS2 has been obtained. These films have an optical band gap, Eg, of 1.86 eV and an electrical conductivity value of 1.2 × 10-3 (Ω cm)-1.

  6. Mineralogy and fluid inclusion studies in kalchoye Copper- gold deposit, East of Esfahan

    Directory of Open Access Journals (Sweden)

    Rezvan Mehvary

    2009-09-01

    Full Text Available Kalchoye Copper-gold deposit is located about 110 kilometers east of Esfahan province and within the Eocene volcano sedimentary rocks. Sandy tuff and andesite lava are important members of this complex.The form of mineralization in area is vein and veinlet and quartz as the main gangue phase. The main ore minerals are chalcopyrite, chalcocite, galena and weathered minerals such as goethite, iron oxides, malachite and azurite. Studies in area indicate that ore mineralization Kalchoye is low sulfide, quartz type of hydrothermal ore deposits and results of thermometry studies on quartz minerals low- medium fluid with low potential mineralization is responsible for mineralization in this area.

  7. Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure

    OpenAIRE

    Song, X.; Caballero, R.; Félix, R.; Gerlach, D.; Kaufmann, C.A.; H. W. Schock; Wilks, R. G.; Bär, M.

    2012-01-01

    The following article appeared in Journal of Applied Physics 111.3 (2012): 034903 and may be found at http://scitation.aip.org/content/aip/journal/jap/111/3/10.1063/1.3679604 Na has deliberately been incorporated into Cu(In,Ga)Se2 (CIGSe) chalcopyrite thin-film solar cell absorbers deposited on Mo-coated polyimide flexible substrates by adding differently thick layers of NaF in-between CIGSe absorber and Mo back contact. The impact of Na on the chemical and electronic surface structure of ...

  8. The German Joint Project "Flexible CIGSe Thin Film Solar Cells for Space Flight

    Science.gov (United States)

    Zajac, Kai; Brunner, Sebastian; John, Ralf; Kaufmann, Christian A.; Otte, Karsten; Rahm, Andreas; Kessler, Friedrich

    2008-09-01

    The purpose of the presented joint project is the development and verification of a flexible, lightweight and highly efficient Cu(In,Ga)Se2 (CIGSe) thin film solar cell technology on polyimide foil substrate for use in space. Due to the worldwide leading present German activities on the field of chalcopyrite based thin film solar cells a harmonisation of resources shall push this development. Furthermore, this project supports the European Space Agency (ESA) program for the development of thin film solar cell technology for space applications. Recent results of substrate evaluation and CIGSe solar cell and module manufacturing on polyimide foil substrate are presented.

  9. Synthesis of Cu-Poor Copper-Indium-Gallium-Diselenide Nanoparticles by Solvothermal Route for Solar Cell Applications

    OpenAIRE

    Chung Ping Liu; Ming Wei Chang; Chuan Lung Chuang; Nien Po Chen

    2014-01-01

    Copper-indium-gallium-diselenide (CIGS) thin films were fabricated using precursor nanoparticle ink and sintering technology. The precursor was a Cu-poor quaternary compound with constituent ratios of Cu/(In+Ga)=0.603, Ga/(In+Ga)=0.674, and Se/(Cu+In+Ga)=1.036. Cu-poor CIGS nanoparticles of chalcopyrite for solar cells were successfully synthesized using a relatively simple and convenient elemental solvothermal route. After a fixed reaction time of 36 h at 180°C, CIGS nanocrystals with diamet...

  10. Fabrication and Characterization of Thin Film Solar Cell Made from CuIn0.75Ga0.25S2 Wurtzite Nanoparticles

    OpenAIRE

    Fengyan Zhang; Chivin Sun; Cyril Bajracharya; Rodriguez, Rene G.; Joshua J. Pak

    2013-01-01

    CuIn0.75Ga0.25S2 (CIGS) thin film solar cells have been successfully fabricated using CIGS Wurtzite phase nanoparticles for the first time. The structure of the cell is Glass/Mo/CIGS/CdS/ZnO/ZnO:Al/Ag. The light absorption layer is made from CIGS Wurtzite phase nanoparticles that are formed from single-source precursors through a microwave irradiation. The Wurtzite phase nanoparticles were converted to Chalcopyrite phase film through a single-step annealing process in the presence of argon an...

  11. The formation of CuInSe{sub 2}-based thin-film solar cell absorbers from alternative low-cost precursors

    Energy Technology Data Exchange (ETDEWEB)

    Jost, S.

    2008-01-18

    This work deals with real-time investigations concerning the crystallisation process of CuInSe{sub 2}-based thin-film solar cell absorbers while annealing differently produced and composed ''low-cost'' precursors. Various types of precursors have been investigated concerning their crystallisation behaviour. Three groups of experiments have been performed: (i) Investigations concerning the crystallisation process of the quaternary chalcopyrite Cu(In,Al)Se{sub 2} and Cu(In,Al)S{sub 2}, (ii) investigations concerning the formation process of the compound semiconductor CuInSe{sub 2} from electroplated precursors, and (iii) investigations concerning the crystallisation of Cu(In,Ga)Se{sub 2} using precursors with thermally evaporated indium. A specific sample surrounding has been constructed, which enables to perform time-resolved angle-dispersive X-ray powder diffraction experiments during the annealing process of precursor samples. A thorough analysis of subsequently recorded diffraction patterns using the Rietveld method provides a detailed knowledge about the semiconductor crystallisation process while annealing. Based on these fundamental investigations, conclusions have been drawn concerning an adaptation of the precursor deposition process in order to optimise the final solar cell results. The investigations have shown, that one class of electroplated precursors shows a crystallisation behaviour identical to the one known for vacuum-deposited precursors. The investigations concerning the crystallisation process of the quaternary chalcopyrite Cu(In,Al)Se{sub 2} revealed, that the chalcopyrite forms from the ternary selenide (Al,In){sub 2}Se{sub 3} and Cu{sub 2}Se at elevated process temperatures. This result is used to explain the separation of the absorber layer into an aluminum-rich and an indium-rich chalcopyrite phase, which has been observed at processed Cu(In,Al)Se{sub 2} absorbers from several research groups. In addition, differences

  12. Geochemical Characteristics of the Jinjiazhuang Ultrabasic Rock—Type Gold Deposit in Chicheng County,Hebei Province

    Institute of Scientific and Technical Information of China (English)

    李红阳; 杨竹森; 等

    2000-01-01

    The Jinjiazhuang gold deposit occurs in the Zhangjiakou gold field,Northwest Hebei.The ore bodies are mostly hosted in Xiaozhangjiakou ultrabasic rocks dominated by diopsidite.Electron microprobe analyses indicate that the deposit is characterized by the enrichment of some platinum group elements in principal metallic minerals such as chalcopyrite,galena,sphalerite and pyrite,and the presence of millerite,Stable isotope studies show that carbon,sulfur and most of the metallogenic elements were probably derived largely from the host Xiaozhangjiakou ultrabasic rocks and that it is possible that the ore-forming fluid was predominted by meteoric water.

  13. Bulk Modulus and Electronic Band Structure of ZnGa2X4 (X=S,Se): a First-Principles Study

    Institute of Scientific and Technical Information of China (English)

    JIANG Xiao-Shu; MI Shu; SUN eeng-Jun; LU Yuan; LIANG Jiu-Qing

    2009-01-01

    First-principles local density functional calculations are presented for the compounds ZnGa2X4 (X = S, Se). We investigate the bulk moduli and electronic band structures in a defect chalcopyrite structure. The lattice constants and internal parameters axe optimized. The electronic structures are analysed with the help of total and partial density of states. The relation between the cohesive energy and the unit cell volume is obtained by fully relaxed structures. We derive the bulk modulus of ZnGa2X4 by fitting the Birch-Murnaghan's equation of state. The extended Cohen's empirical formula agrees well with our ab initio results.

  14. Effect of radiation on wettability and floatability of sulfide minerals

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    The feasibility for modifying the wettability and floatability of sulfide minerals by electron beam irradiation has been studied experimentally. The wettability of crystalline pyrite and floatability of some sulfide as pyrite, arsenopyrite, chalcopyrite and marmatite after irradiation were examined by flotation in a modified Hallimond tube. Experimental results show that the hydrophobicity of crystalline pyrite enhances with the increase of irradiation dose in a low dose range. And the flotation responses of sulfide minerals on irradiation dosevary with the mineral species and particle size. The floatability of minerals can be regulated by altering irradiation dose. An explanationfor the mechanism has been suggested based on the principle of radiation chemistry.

  15. High intensity polarized electron sources

    Energy Technology Data Exchange (ETDEWEB)

    Sinclair, C.K.

    1980-10-01

    The status of the polarized electron source development program at SLAC will be reviewed. Emission currents of 60 A, corresponding to a space charge limited current density of 180 A/cm/sup 2/, have been obtained from GaAs photocathodes. Electron beam polarization 20% greater than that obtainable from GaAs cathodes has been observed from multilayer GaAs-GaAlAs structures. Work in progress to produce high beam polarization from II-IV-V/sub 2/ chalcopyrite photocathodes will also be described.

  16. Laser annealing and defect study of chalcogenide photovoltaic materials

    Science.gov (United States)

    Bhatia, Ashish

    Cu(In,Ga)Se2 (CIGSe), CuZnSn(S,Se)4(CZTSSe), etc., are the potential chalcogenide semiconductors being investigated for next-generation thin film photovoltaics (TFPV). While the champion cell efficiency of CIGSe has exceeded 20%, CZTSSe has crossed the 10% mark. This work investigates the effect of laser annealing on CISe films, and compares the electrical characteristics of CIGSe (chalcopyrite) and CZTSe (kesterite) solar cells. Chapter 1 through 3 provide a background on semiconductors and TFPV, properties of chalcopyrite and kesterite materials, and their characterization using deep level transient spectroscopy (DLTS) and thermal admittance spectroscopy (TAS). Chapter 4 investigates electrochemical deposition (nonvacuum synthesis) of CISe followed by continuous wave laser annealing (CWLA) using a 1064 nm laser. It is found that CWLA at ≈ 50 W/cm2 results in structural changes without melting and dewetting of the films. While Cu-poor samples show about 40% reduction in the full width at half maximum of the respective x-ray diffraction peaks, identically treated Cu-rich samples register more than 80% reduction. This study demonstrates that an entirely solid-phase laser annealing path exists for chalcopyrite phase formation and crystallization. Chapter 5 investigates the changes in defect populations after pulse laser annealing in submelting regime of electrochemically deposited and furnace annealed CISe films. DLTS on Schottky diodes reveal that the ionization energy of the dominant majority carrier defect state changes nonmonotonically from 215+/-10 meV for the reference sample, to 330+/-10 meV for samples irradiated at 20 and 30 mJ/cm2, and then back to 215+/-10 meV for samples irradiated at 40 mJ/cm2. A hypothesis involving competing processes of diffusion of Cu and laser-induced generation of In vacancies may explain this behavior. Chapter 6 compares the electrical characteristics of chalcopyrite and kesterite materials. Experiments reveal CZTSe cell has an

  17. The Chahe Copper Deposit—Its Age and Genesis

    Institute of Scientific and Technical Information of China (English)

    张玉学; 邵树勋; 等

    1995-01-01

    The Chahe copper deposit occurs in the Early Proterozoic metamorphic series in the area of Chahe and its chalcopyrite yielded a Pb-Pb isochron age of 951±36 Ma ,providing evidence for copper mineralization at the early stage of the Jinning movement. The ore -forming material came from terrestrial clastic sediments and marine volcamic eruption and the ores were deposited in a relatively open beach environment. The Jinning movement led to folding and metamorphism of country strata, as well as to the rebomilization and transport of copper ,resulting in ore deposition in structurally weak locations. This deposit is a volcano-sedimentary metamorphic deposit.

  18. Emilite,  Cu10.72Pb10.72Bi21.28S48, the last missing link of the bismuthinite-aikinite series?

    DEFF Research Database (Denmark)

    Topa, Dan; H. Paar, Werner; Balic Zunic, Tonci

    2006-01-01

    and 0.1 mm in diameter. The associated minerals are: bismuthinite derivatives in the range krupkaite-hammarite, Ag-bearing lillianite, makovickyite, pavonite, cosalite, galenobismutite, cannizzarite, tetradymite, native bismuth, chalcopyrite, pyrite and quartz. Emilite is opaque, with a metallic luster...... and a greyish black streak. In refl ected light, it has a greyish white color with a distinct anisotropy and perceptible birefl ectance in air and oil, without internal refl ections. The measured values of refl ectance in air are: 39.4-46.95 (470 nm), 39.21-48.25 (546 nm), 38.98-48.35 (589 nm), 38.30-46.94 (650...

  19. Research Update: Cu-S based synthetic minerals as efficient thermoelectric materials at medium temperatures

    Science.gov (United States)

    Suekuni, Koichiro; Takabatake, Toshiro

    2016-10-01

    Synthetic minerals and related systems based on Cu-S are attractive thermoelectric (TE) materials because of their environmentally benign characters and high figures of merit at around 700 K. This overview features the current examples including kesterite, binary copper sulfides, tetrahedrite, colusite, and chalcopyrite, with emphasis on their crystal structures and TE properties. This survey highlights the superior electronic properties in the p-type materials as well as the close relationship between crystal structures and thermophysical properties. We discuss the mechanisms of high power factor and low lattice thermal conductivity, approaching higher TE performances for the Cu-S based materials.

  20. Formation of CuInSe{sub 2} from Cu{sub 2}Se and In{sub 2}Se{sub 3} compounds

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Daigao [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui (China); Wang, Deliang [Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui (China); CAS Key Laboratory of Materials for Energy Conversion, University of Science and Technology of China, Hefei, Anhui (China)

    2011-10-15

    Chalcopyrite {alpha}-CuInSe{sub 2} ({alpha}-CIS) was prepared from mixed powders of Cu{sub 2}Se and In{sub 2}Se{sub 3} by annealing in the Se- and the non-Se environments. The mechanically ground powders were in an overall amorphous state. The mechanical alloying produced Cu{sub 3}Se{sub 2} and CuSe compounds. At relatively low temperature, Cu{sub 3}Se{sub 2} decomposed, Cu{sub 2-x}Se and CuSe formed. The reaction for the formation of {alpha}-CuInSe{sub 2} occurred essentially at a temperature at {proportional_to}350 C in both the Se- and the non-Se environments. In the non-Se environment, reactions occurred by a solid-solid reaction and a certain amount of Se were released from the mixed powder, resulting in poor crystalline {alpha}-CuInSe{sub 2} powders. When annealed in the Se environment, low-melting Se-rich Cu-Se compounds were produced during reaction. The reactions occurred by a liquid-solid reaction above 450 C. Large-grained and good crystalline quality of chalcopyrite CIS with near stoichiometric atomic ratio was obtained above 450 C. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  1. Effect of ph on the Electrodeposition of Cu(In, Al)Se2 from Aqueous Solution in Presence of Citric Acid as Complexing Agent

    Science.gov (United States)

    Ganjkhanlou, Yadolah; Ebadzadeh, Touradj; Kazemzad, Mahmood; Maghsoudipour, Amir; Kianpour-Rad, Mansoor

    2015-05-01

    Effect of pH on the one-step electrodeposition of Cu(In, Al)Se2 chalcopyrite layer in the presence of citric acid has been investigated by applying different electrochemical and characterization techniques. It has been observed that at pH of 1.5, nanocrystalline phase of chalcopyrite and small amount of binary phase of Cu2Se with overall composition of Cu0.91In0.32Al0.39Se2 have been deposited. On the other hand, at pH of 4, the film composition changed to Cu1.9In0.05Al0.21Se2 and an additional binary phase of copper selenide (CuSe) has also been formed. Morphological investigation illustrated that smooth and compact layer with fine spherical particles having the size of 20 nm has been obtained at pH of 1.5 whereas mixture of planar and spherical particles with size of 450-550 nm have been formed at pH of 4. In alkaline environment (pH 9), the deposition current has been noticeably decreased and no deposition occurred due to the formation of a stable complex of citric acid with metal ions. The mechanism of citric acid interaction with metal ions at different pH has also been studied by cyclic voltammetry measurement.

  2. Application of Raman Spectroscopy to the Biooxidation Analysis of Sulfide Minerals

    Directory of Open Access Journals (Sweden)

    J. V. García-Meza

    2012-01-01

    Full Text Available We report the application of confocal laser scanning microscopy CLSM and Raman spectroscopy on the (biochemical oxidation of pyrite and chalcopyrite, in order to understand how surface sulfur species (S2−/S0 affects biofilm evolution during mineral colonization by Acidithiobacillus thiooxidans. We found that cells attachment occurs as cells clusters and monolayered biofilms within the first 12 h. Longer times resulted in the formation of micro- and macrocolonies with variable cell density and higher epifluorescence signal of the extracellular polymeric substances (EPS, indicating double dynamic activity of A. thiooxidans: sulfur biooxidation and biofilm formation. Raman spectra indicated S2−/S0 consumption modification during biofilm evolution. Hence, cell density increase was primarily associated with the presence of S0; the presence of refractory sulfur species on the mineral surfaces does not to affect biofilm evolution. The EPS of the biofilms was mainly composed of extracellular hydrophobic compounds (vr. gr. lipids and a minor content of hydrophilic exopolysaccharides, suggesting a hydrophobic interaction between attached cells and the altered pyrite and chalcopyrite.

  3. High temperature bacterial leaching: HIOX project

    Energy Technology Data Exchange (ETDEWEB)

    Morin, D.; D' Hugues, P.; Bonney, C. F.; Norris, P.; Shwab, W.; Sundkvist, J-E.; Bridges, P. [Bureau de Recherhes Geologiques et Minieres, Orleans (France)

    2001-07-01

    The HIOX project was designed to investigate the use of thermophilic bacterial cultures for the leaching of chalcopyrite (CuFeS{sub 2}, the natural source of copper). Beyond bacterial leaching, the study also encompassed the downstream processing steps in an effort to develop a new method for the recovery of copper in an economical and environmentally-friendly process. Using the HIOX process copper recovery was increased to better than 90 per cent within 5 days with a 12 per cent solids culture, although some potentially limiting factors such as foam generation, nutrient concentrations and mixing/aeration efficiency were also identified. The study resulted in the establishment of a mass balance based on a simplified flowsheet of the process. Techno-economic evaluation carried out at three sites indicated technical feasibility using relatively conventional equipment and capital and operating costs in ranges that suggest that bioleaching with high temperature bacteria is an attractive alternative for the treatment of chalcopyrite concentrate. 5 tabs.

  4. Preparation and characterization of (CuInSe{sub 2}){sub 1-x}(CoSe){sub x} alloys in the composition range 0{<=}x{<=}2/3

    Energy Technology Data Exchange (ETDEWEB)

    Grima-Gallardo, P.; Munoz, M.; Ruiz, J.; Power, C.; Gonzalez, J. [Centro de Estudios en Semiconductores (C.E.S.), Dpto. Fisica, Fac. Ciencias, Universidad de Los Andes, La Hechicera, Merida (Venezuela); LeGodec, Y.; Munsch, P.; Itie, J.P. [Laboratoire de Physique des Milieux Condenses, Universite Pierre et Marie Curie, Paris VI, Paris (France); Briceno, V. [Facultad Experimental de Ciencias y Tecnologia (FACYT), Dpto. Fisica, Universidad de Carabobo, Valencia (Venezuela); Briceno, J.M. [Laboratorio de Analisis Quimico y Estructural (LAQUEM), Dpto. Fisica, Fac. Ciencias, La Hechicera, Merida (Venezuela)

    2004-07-01

    Polycrystalline samples of (CuInSe{sub 2}){sub 1-x}(CoSe){sub x} alloys were prepared by the normal melt and anneal technique in the composition range 0chalcopyrite structure exists in a narrow interval 0chalcopyrite-like phase ({alpha}{sup ''}) was observed together with traces of the {gamma} phase. The sequence of phase transformations in the studied composition range seems to be {alpha} {yields} {alpha}' {yields} {alpha}'+{gamma} {yields} {alpha}{sup ''}+{gamma}. (copyright 2004 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  5. Leaching of complex sulphide concentrate in acidic cupric chloride solutions

    Institute of Scientific and Technical Information of China (English)

    M. TCHOUMOU; M. ROYNETTE

    2007-01-01

    The chemical analysis of a complex sulphide concentrate by emission spectrometry and X-ray diffraction shows that it contains essentially copper, lead, zinc and iron in the form of chalcopyrite, sphalerite and galena. A small amount of pyrite is also present in the ore but does not be detected with X-ray diffraction. The cupric chloride leaching of the sulphide concentrate at various durations and solid/liquid ratios at 100 ℃ shows that the rate of dissolution of the ore is the fastest in the first several hours, and after 12 h it does not evolve significantly. If oxygen is excluded from the aqueous cupric chloride solution during the leaching experiment at 100 ℃, the pyrite in the ore will not be leached. The determination of principal dissolved metals in the leaching liquor by flame atomic absorption spectrometry, and the chemical analysis of solid residues by emission spectrometry and X-ray diffraction allow to conclude that the rate of dissolution of the minerals contained in the complex sulphide concentrate are in the order of galena>sphalerite>chalcopyrite.

  6. Isolation of Leptospirillum ferriphilum by single-layered solid medium

    Institute of Scientific and Technical Information of China (English)

    LIU Jian-she; XIE Xue-hui; XIAO Sheng-mu; WANG Xiu-mei; ZHAO Wen-jie; TIAN Zhuo-li

    2007-01-01

    According to physiological and biochemical characteristics of Leptospirillum ferriphilum, a strain of object bacteria was isolated successfully. Bacteria were enriched by selective liquid medium and plated on designed single-layered agar solid medium.Colony was cultured and bacteria were collected. The morphologies of the object bacteria were observed using crystal violet staining,scanning electron microscope(SEM) and transmission electron microscope (TEM). The result of 16S rDNA identification shows that this bacterium belongs to Leptospirillum ferriphilum and it is named as Leptospirillum ferriphilum strain D1. These results indicate that this new single-layered agar solid medium is efficient and simple for isolation of Leptospirillum ferriphilum. Additionally,physiological-biochemical characteristics show that the optimum initial pH value and its growth temperature are 1.68 and 40 ℃,respectively. The culture of it is used to leach a complex concentrate chalcopyrite, the leaching efficiencies of copper and iron are 1.93% and 13.74%, respectively, and it is more effective than the A.ferrooxidans culture in the leaching of the complex concentrate chalcopyrite.

  7. Synthesis of CuIn{sub x}Ga{sub 1−x}Se{sub 2} nanoparticles in organic solvent for thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Hahn, Jae-Sub [Department of Nano and Chemical Engineering, Kunsan National University, Jeonbuk, 573–701 (Korea, Republic of); Lee, Soo-Ho; Seo, Moon-Soo [School of Information and Communication Engineering, Sungkyunkwan University, Suwon, 440–746 (Korea, Republic of); Choi, Dae-Kyu [School of New Material Science, Chonbuk National University, Jeonbuk, 561, 756 (Korea, Republic of); Lee, Jaehyeong [School of Information and Communication Engineering, Sungkyunkwan University, Suwon, 440–746 (Korea, Republic of); Shim, Joongpyo, E-mail: jpshim@kunsan.ac.kr [Department of Nano and Chemical Engineering, Kunsan National University, Jeonbuk, 573–701 (Korea, Republic of)

    2013-11-01

    Chalcopyrite CuIn{sub 1−x}Ga{sub x}Se{sub 2} (CIGS; x < 0.3) nanoparticles were synthesized by reacting CuCl, InCl{sub 3}, GaCl{sub 3} and Se in oleyl amine over 250 °C. Depending on the reaction temperature and duration, the obtained nanoparticles had sizes of less than 100 nm and different chemical compositions. Because the atomic percentage of Se decreased with increasing reaction time, the proportion of Se and Ga content also changed. Furthermore, the lattice parameters, a and c, changed with increasing reaction temperature and time. Lastly, the bandgap energies of the CIGS films coated on glass plates were ∼ 0.98 eV and did not significantly change with increasing heat-treatment temperature. - Highlights: • CuIn{sub 1−x}Ga{sub x}Se{sub 2} (x < 0.3) nanoparticles synthesized by solution process in oleyl amine. • Se an Ga content in chalcopyrite particles increased with reaction time. • The nanoparticle lattice parameters changed with reaction temperature and time. • Band gaps remained fairly stable upon change of reaction temperature and time.

  8. Flotation separation of arsenopyrite from several sulphide minerals with organic depressants

    Institute of Scientific and Technical Information of China (English)

    Wang Fuliang; Wang Ligang; Sun Chuanyao

    2008-01-01

    In this paper,the separation of arsenopyrite from chalcopyrite,pyrite,galena with organic depressants (guergum and sodium humic)was discussed,and the functioning mechanism of those organic depressants was dis-cussed.The experimental results of monomineral flotation indicated that both guergum and sodium humic have depress-ing effect on arsenopyrite in the presence of ethyl xanthate.Guergum and sodium humic showed different depressing a-bility to pyrite,chalcopyrite and galena,and the higher the pH value in pulp,the stronger the depressing ability.Ultra-violet-Visible Spectrophotometric study showed that the adsorption layer of xanthate on surface of minerals had been de-sorbed by the two organic depressants,and the selective desorption of the collector layer was found from different miner-als.The xanthate cover on minerals surface was set free when dosage of the organic depressants was high enough.For artificially-mixed minerals,the separation of arsenopyrite from other sulphides was successfully realized by controlling dosage of the organic depressants.And sodium humic had been used successfully to decrease arsenic content in sulphide concentr ates in a commercial Lead-Zinc concentrator.

  9. Nonideal anion displacement, band gap variation, and valence band splitting in Cu-In-Se compounds

    Energy Technology Data Exchange (ETDEWEB)

    Reena Philip, Rachel [Solid State Physics Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi-682022 Kerala (India)]. E-mail: reenatara@cusat.ac.in; Pradeep, B. [Solid State Physics Laboratory, Department of Physics, Cochin University of Science and Technology, Kochi-682022 Kerala (India)

    2005-01-24

    Polycrystalline thin films of ternary chalcopyrite CuInSe{sub 2} and defect compounds CuIn{sub 3}Se{sub 5} and CuIn{sub 5}Se{sub 8} are prepared in vacuum by three-source coevaporation method. Structural and optical characterizations of the films are done using X-ray diffraction (XRD), energy-dispersive X-ray analysis (EDAX), and optical absorbance spectra measurements. With variation in the composition of CuInSe{sub 2}, a change over from p-type to n-type conductivity is observed (as noted by the hot probe method). The deformation parameters and the anion displacements are calculated from the X-ray diffraction data, and the cation-anion bond lengths are deduced. The dependence of band gap variation on nonideal anion displacement in the ternary compounds and the effect of Se-p-Cu-d repulsion on band gap are studied. The threefold optical structure observed in the fundamental absorption region of the absorption spectra is analysed to extract the valence band splitting parameters. Hopfields quasi-cubic model adapted for chalcopyrites with tetragonal deformation is used to determine the crystal field splittings and spin orbit splittings, and the linear hybridization model is used to calculate the percentage of d-orbital and p-orbital contribution to hybridization in the compounds under consideration.

  10. Solution transformation of Cu₂O into CuInS₂ for solar water splitting.

    Science.gov (United States)

    Luo, Jingshan; Tilley, S David; Steier, Ludmilla; Schreier, Marcel; Mayer, Matthew T; Fan, Hong Jin; Grätzel, Michael

    2015-02-11

    Though Cu2O has demonstrated high performance as a photocathode for solar water splitting, its band gap is too large for efficient use as the bottom cell in tandem configurations. Accordingly, copper chalcopyrites have recently attracted much attention for solar water splitting due to their smaller and tunable band gaps. However, their fabrication is mainly based on vacuum evaporation, which is an expensive and energy consuming process. Here, we have developed a novel and low-cost solution fabrication method, and CuInS2 was chosen as a model material due to its smaller band gap compared to Cu2O and relatively simple composition. The nanostructured CuInS2 electrodes were synthesized at low temperature in crystalline form by solvothermal treatment of electrochemically deposited Cu2O films. Following the coating of overlayers and decoration with Pt catalyst, the as-fabricated CuInS2 electrode demonstrated water splitting photocurrents of 3.5 mA cm(-2) under simulated solar illumination. To the best of our knowledge, this is the highest performance yet reported for a solution-processed copper chalcopyrite electrode for solar water splitting. Furthermore, the electrode showed good stability and had a broad incident photon-to-current efficiency (IPCE) response to wavelengths beyond 800 nm, consistent with the smaller bandgap of this material.

  11. Structural, electronic and optical properties of AgXY{sub 2}(X = Al, Ga, In and Y = S, Se, Te)

    Energy Technology Data Exchange (ETDEWEB)

    Ullah, Saeed; Din, Haleem Ud [Materials Modeling Lab, Department of Physics, Islamia College University, Peshawar (Pakistan); Murtaza, G., E-mail: murtaza@icp.edu.pk [Materials Modeling Lab, Department of Physics, Islamia College University, Peshawar (Pakistan); Ouahrani, T. [Laboratoire de Physique Théorique, B.P. 119, Université de Tlemcen, Tlemcen 13000 (Algeria); Khenata, R., E-mail: khenata_rabah@yahoo.fr [Laboratoire de Physique Quantique et de Modélisation Mathématique, Université de Mascara, Mascara 29000 (Algeria); Naeemullah [Department of Physics, G.D.C. Darra Adam Khel, F.R. Kohat, KPK (Pakistan); Bin Omran, S. [Department of Physics and Astronomy, College of Science, King Saud University, P.O. Box 2455, Riyadh 11451 (Saudi Arabia)

    2014-12-25

    Highlights: • The compounds are studied by FP-LAPW method within mBJ approximation. • All of the studied materials show isotropic behavior. • All the compounds show direct band gap nature. • Bonding nature is mostly covalent among the studied compounds. • High absorption peaks and reflectivity ensures there utility in optoelectronic devices. - Abstract: The structural, electronic and optical properties of the ternary semiconducting compounds AgXY{sub 2} (X = Al, Ga, In and Y = S, Se, Te) in Heusler and chalcopyrite crystal phases have been investigated using the density functional theory (DFT) based on the full potential linear augmented plane wave (FP-LAPW) method. The calculated lattice constant and band gap values for AgXY{sub 2} in chalcopyrite phase are in good agreement with the available experimental data. Band structure calculations are performed using modified Becke–Johnson (mBJ) method which match closely with experimental data and yield better band gaps rather than those obtained by using generalized gradient approximation (GGA) and Engel–Vosko generalized gradient approximation (EV–GGA). Decrease in band gap is observed by changing cations X and Y from the top to bottom of periodic table. Chemical bonding trends are predicted through charge density plots and quantified by Bader’s analysis. Optical properties reveal that these compounds are suitable candidates for optoelectronic devices in the visible and ultraviolet (UV) regions.

  12. The Effects of Annealing Parameters on the Crystallization and Morphology of Cu(In,GaSe2 Absorber Layers Prepared by Annealing Stacked Metallic Precursors

    Directory of Open Access Journals (Sweden)

    Chia-Ho Huang

    2014-01-01

    Full Text Available CIGS films are prepared by single-stage annealing of the solid Se-coated In/Cu-Ga bilayer precursor. The annealing processes were performed using various Ar pressures, heating rates, and soaking times. A higher Ar pressure is needed to fabricate highly crystalline CIGS films, as no extra Se-vapor source is supplied. As the heating rate increases, the surface morphologies of the CIGS films become looser and some cracks are observed. However, the influence of soaking time is insignificant and the selenization process only requires a short time when the precursors are selenized at a higher temperature with a lower heating rate and a higher Ar pressure. In this study, a dense chalcopyrite CIGS film with a thickness of about 1.5-1.6 μm, with large grains (~1.2 μm and no cracking or peeling is obtained after selenizing at a temperature of 550°C, an Ar pressure of 300 Torr, a heating rate of 60°C/min, and a soaking time of 20 min. By adequate design of the stacked precursor and controlling the annealing parameters, single-stage annealing of the solid Se-coated In/Cu-Ga bilayer precursor is simplified for the fabrication of a fully crystallized chalcopyrite CIGS absorber layers with good crystallization and large grains.

  13. Ore genesis at the Monterrosas deposit in the Coastal Batholith, Ica, Peru

    Science.gov (United States)

    Sidder, G. B.

    1984-06-01

    Monterosas is a hydrothermal deposit of copper and for that is hosted by gabbro-diorites of the Upper Cretaceous Patap Superunit within the Coastal Batholith of central Peru. The ore body is localized by fractures and splays related to a nearby regional fault and is composed of massive chalcopyrite, magnetite, and pyrite. Ore and alteration minerals such as actinolite, sodic scapolite, epidotes, sphene, magnetite, apatite, tourmaline, chlorites, hematite, and quartz formed dominantly as replacements of magmatic diosside, labradorite-andesine, and ilmenite. Hydrothermal mineralization was characterized by the exchange of major, minor, and trace elements between hot saline fluids and gabbro-diorite wall rocks. Geochemical data suggest that the ore and gangue minerals were deposited at high temperatures from saline fluids derived from a magma. The evidence includes fluid inclusions within gangue quartz that exhibit homogenization temperatures of 400 to 500 C, salinites of 32 to 56 wt percent NaCl and the halite trend, and magmatic like sulfur isotopic compositions that range from 1.6 to 3.3 permit in gyrite and chalcopyrite.

  14. Nanoparticle-induced grain growth of carbon-free solution-processed CuIn(S,Se)2 solar cell with 6% efficiency.

    Science.gov (United States)

    Cai, Yongan; Ho, John C W; Batabyal, Sudip K; Liu, Wei; Sun, Yun; Mhaisalkar, Subodh G; Wong, Lydia H

    2013-03-13

    Chalcopyrite-based solar cell deposited by solution processes is of great research interest because of the ease of fabrication and cost effectiveness. Despite the initial promising results, most of the reported methods encounter challenges such as limited grain growth, carbon-rich interlayer, high thermal budget, and the presence of secondary Cu-rich phases, which limit the power conversion efficiency (PCE). In this paper, we develop a new technique to deposit large grain, carbon-free CISSe absorber layers from aqueous nanoparticle/precursor mixture which resulted in a solar cell with PCE of 6.2%. CuCl2, InCl3, and thiourea were mixed with CuS and In2S3 nanoparticles in water to form the unique nanoparticle/precursor solution. The Carbon layer formation was prevented because organic solvents were not used in the precursor. The copper-rich (CuS) nanoparticles were intentionally introduced as nucleation sites which accelerate grain growth. In the presence of nanoparticles, the grain size of CISSe film increased by a factor of 7 and the power conversion efficiency of the solar cell is 85% higher than the device without nanoparticle. This idea of using nanoparticles as a means to promote grain growth can be further exploited for other types of chalcopyrite thin film deposited by solution methods.

  15. Chemical structures of the Cu(In,Ga)Se2/Mo and Cu(In,Ga)(S,Se)2/Mo interfaces

    Science.gov (United States)

    Bär, M.; Weinhardt, L.; Heske, C.; Nishiwaki, S.; Shafarman, W. N.

    2008-08-01

    Using a suitable lift-off technique, we have investigated the chemical properties of the interface between Mo and chalcopyrite compound semiconductors by x-ray photoelectron spectroscopy and x-ray excited Auger-electron spectroscopy. By a systematic comparison of interfaces between S-free [ Cu(In,Ga)Se2 (CIGSe)] as well as S-containing [ Cu(In,Ga)(S,Se)2 (CIGSSe)] chalcopyrites and Mo, we find that the chemical structure at the CIG(S)Se/Mo interface is strongly influenced by the presence or absence of S. We observe an interfacial MoSe2 [Mo(SZSe1-Z)2] layer formed between CIGSe [CIGSSe] and the Mo layer. The Mo(SZSe1-Z)2 layer appears significantly thinner than the MoSe2 layer and exhibits a different S/(S+Se) ratio [Z=0.9(1)] than the CIGSSe back side [0.5(7)], giving insight into the “competition” between S and Se during contact formation. Furthermore, we find a significant Ga accumulation at the Mo back contact, which points to pronounced chemical interactions during the formation of the CIG(S)Se/Mo interface.

  16. Synthesis of Cu-Poor Copper-Indium-Gallium-Diselenide Nanoparticles by Solvothermal Route for Solar Cell Applications

    Directory of Open Access Journals (Sweden)

    Chung Ping Liu

    2014-01-01

    Full Text Available Copper-indium-gallium-diselenide (CIGS thin films were fabricated using precursor nanoparticle ink and sintering technology. The precursor was a Cu-poor quaternary compound with constituent ratios of Cu/(In+Ga=0.603, Ga/(In+Ga=0.674, and Se/(Cu+In+Ga=1.036. Cu-poor CIGS nanoparticles of chalcopyrite for solar cells were successfully synthesized using a relatively simple and convenient elemental solvothermal route. After a fixed reaction time of 36 h at 180°C, CIGS nanocrystals with diameters in the range of 20–70 nm were observed. The nanoparticle ink was fabricated by mixing CIGS nanoparticles, a solvent, and an organic polymer. Analytical results reveal that the Cu-poor CIGS absorption layer prepared from a nanoparticle-ink polymer by sintering has a chalcopyrite structure and a favorable composition. For this kind of sample, its mole ratio of Cu : In : Ga : Se is equal to 0.617 : 0.410 : 0.510 : 2.464 and related ratios of Ga/(In+Ga and Cu/(In+Ga are 0.554 and 0.671, respectively. Under the condition of standard air mass 1.5 global illumination, the conversion efficiency of the solar cell fabricated by this kind of sample is 4.05%.

  17. Bacterial leaching of a sulfide ore by Thiobacillus ferrooxidans and Thiobacillus thiooxidans: I. Shake flask studies.

    Science.gov (United States)

    Lizama, H M; Suzuki, I

    1988-06-20

    Bacterial leaching of a sulfide ore containing pyrite, chalcopyrite, and sphalerite was studied in shake flask experiments using Thiobacillus ferrooxidans and Thiobacillus thiooxidans strains isolated from mine sites. The Fe(2+)grown T. ferrooxidans isolates solubilized sphalerite preferentially over chalcopyrite leaching 7-10% Cu, 68-76% Zn, and 10-22% Fe from the ore in 18 days. The sulfur grown T. thiooxidans isolates leached Zn much more slowly and very little Fe, with a Cu-Zn extraction ratio twice the value obtained with T. ferrooxidans. The ore adapted T. ferrooxidans started solubilizing Cu and Zn without a lag period. The ore-adapted T. thiooxidans extracted Cu as well as T. ferrooxidans, but the extraction of Zn or Fe was still much slower in the low-phosphate medium, while in the high-phosphate medium it approached the value obtained with T. ferrooxidans. A high Cu-Zn extraction ratio of 0.34 was obtained with T. thiooxidans in the low phosphate medium. In the mixed-culture experiments with T. ferrooxidans and T. thiooxidans, the culture behaved as T. thiooxidans in the low-phosphate medium with a higher Cu-Zn extraction ratio and as T. ferrooxidans in the high-phosphate medium with a lower Cu-Zn extraction ratio. It is concluded that T. ferrooxidans and T. thiooxidans solubilize sulfide minerals by different mechanisms.

  18. Fe-isotope fractionation in magmatic-hydrothermal mineral deposits: A case study from the Renison Sn-W deposit, Tasmania

    Science.gov (United States)

    Wawryk, Christine M.; Foden, John D.

    2015-02-01

    We present 50 new iron isotopic analyses of source granite and mineral separates from the Renison tin deposit in western Tasmania. The aim of the study is to characterise the composition of minerals within a tin deposit associated with a reduced, S-type magma. We have analysed bulk samples of granite, and separates of pyrrhotite, pyrite, arsenopyrite, magnetite, chalcopyrite and siderite by multi-collector inductively coupled mass spectrometry. The isotopic compositions of mineral separates are consistent with theoretical predictions of equilibrium fractionation based on Mössbauer spectroscopy and other parametric calculations. Mineral-mineral pairs yield temperatures of formation that are in agreement with prior detailed fluid inclusion studies, but are spatially inconsistent with declining fluid temperatures with distance from the causative intrusion, limiting the use of Fe isotopes as a potential geothermometer, at least in this case. Comparison of our data with published data from other deposits clearly demonstrates that pyrite, magnetite and chalcopyrite from the hottest ore fluids (>300-400 °C) at Renison are isotopically heavier than minerals sampled from a deposit formed at similar temperatures, but associated with a more oxidised and less differentiated intrusion.

  19. Invisible gold in Colombian auriferous soils

    Energy Technology Data Exchange (ETDEWEB)

    Bustos Rodriguez, H., E-mail: hbustos@ut.edu.co; Oyola Lozano, D.; Rojas Martinez, Y. A. [Universidad del Tolima, Departamento de Fisica (Colombia); Perez Alcazar, G. A. [Universidad del Valle, Departamento de Fisica (Colombia); Balogh, A. G. [Darmstadt University of Technology, Institute of Materials Science (Germany)

    2005-11-15

    Optic microscopy, X-ray diffraction (XRD), Moessbauer spectroscopy (MS), Electron microprobe analysis (EPMA) and secondary ions mass spectroscopy (SIMS) were used to study Colombian auriferous soils. The auriferous samples, collected from El Diamante mine, located in Guachavez-Narino (Colombia), were prepared by means of polished thin sections and polished sections for EPMA and SIMS. Petrography analysis was made using an optical microscope with a vision camera, registering the presence, in different percentages, of the following phases: pyrite, quartz, arsenopyrite, sphalerite, chalcopyrite and galena. By XRD analysis, the same phases were detected and their respective cell parameters calculated. By MS, the presence of two types of pyrite was detected and the hyperfine parameters are: {delta}{sub 1} = 0.280 {+-} 0.01 mm/s and {Delta}Q{sub 1} = 0.642 {+-} 0.01 mm/s, {delta}{sub 2} = 0.379 {+-} 0.01 mm/s and {Delta}Q{sub 2} = 0.613 {+-} 0.01 mm/s. For two of the samples MS detected also the arsenopyrite and chalcopyrite presence. The mean composition of the detected gold regions, established by EPMA, indicated 73% Au and 27% Ag (electrum type). Multiple regions of approximately 200 x 200 {mu}m of area in each mineral sample were analyzed by SIMS registering the presence of 'invisible gold' associated mainly with the pyrite and occasionally with the arsenopyrite.

  20. AES depth profile and photoconductive studies of AgInS2 thin films prepared by co-evaporation

    Directory of Open Access Journals (Sweden)

    C. A Arredondo

    2014-06-01

    Full Text Available In this study, thin films of AgInS2 with chalcopyrite-type tetragonal structure were grown by means of a procedure based on the sequential evaporation of metallic precursors in presence of elemental sulfur in a two-stage process. The effect of the growth temperature and the proportion of the evaporated Ag mass in relation to the evaporated In mass (mAg/mIn on the phase and homogeneity in the chemical composition were researched through X-ray diffraction measurements and Auger electrons spectroscopy. These measurements evidenced that the conditions for preparing thin films containing only the AgInS2 phase, grown with tetragonal chalcopyrite-type structure and good homogeneity of the chemical composition in the entire volume, are a temperature of 500 °C and a 0.89 mAg/mIn proportion. The transient photocurrent measurements indicated that the electricity transmission is affected by recombination processes via band-to-band transitions and trap-assisted transitions.

  1. Untersuchungen von Defektchalkopyrithalbleitern [vacancy] AB$_2$C$_4$ mit der Methode der gestoerten $\\gamma-\\gamma$- Winkelkorrelation (PAC)

    CERN Document Server

    Dietrich, M

    1998-01-01

    The compounds [vacancy]AB$_2$C$_4$ with defect chalcopyrite structure are especially interesting among the ternary semiconductors. The reason is the occurrence of vacancies in an ordered and stoichiometric manner. Representatives of defect chalcopyrites have been implanted with radioactive probe isotopes mainly at the mass separator ISOLDE at CERN. The nuclear quadrupole interactions of the probe nuclei with the electric field gradients at lattice sites have been observed with perturped $\\gamma-\\gamma$ -angular correlation spectroscopy (PAC). The annealing of the implantation induced lattice damage takes place at temperatures in between 700 K and 1100 K in the substances investigated. $^{117}$Cd, $^{111}$In and $^{77}$Br substitute the Cd-site, both Ga-sites and the Se-site, resp., in CdGa$_2$Se$_4$. The probe $^{111}$Ag substitutes the vacancy. Both the experimentally and the theoretically determined electric field gradients are in the order of magnitude of 10E21 V/m$^2$. At elevated temperatures, disorder o...

  2. Structural Investigation of Photocatalyst Solid Ag1−xCuxInS2 Quaternary Alloys Sprayed Thin Films Optimized within the Lattice Compatibility Theory (LCT Scope

    Directory of Open Access Journals (Sweden)

    A. Colantoni

    2014-01-01

    Full Text Available CuxAg1−xInS2 solid thin films were fabricated through a low-cost process. Particular process-related enhanced properties lead to reaching a minimum of lattice mismatch between absorber and buffer layers within particular solar cell devices. First, copper-less samples X-ray diffraction analysis depicts the presence of AgInS2 ternary compound in chalcopyrite tetragonal phase with privileged (112 peak (d112=1.70 Å according to JCPDS 75-0118 card. Second, when x content increases, we note a shift of the same preferential orientation (112 and its value reaches 1.63 Å corresponding to CuInS2 chalcopyrite tetragonal material according to JCPDS 89-6095 file. Finally, the formation and stability of these quaternaries have been discussed in terms of the lattice compatibility in relation with silver-copper duality within indium disulfide lattice structure. Plausible explanations for the extent and dynamics of copper incorporation inside AgInS2 elaborated ternary matrices have been proposed.

  3. Textural and stable isotope studies of the Big Mike cupriferous volcanogenic massive sulfide deposit, Pershing County, Nevada.

    Science.gov (United States)

    Rye, R.O.; Roberts, R.J.; Snyder, W.S.; Lahusen, G.L.; Motica, J.E.

    1984-01-01

    The Big Mike deposit is a massive sulphide lens entirely within a carbonaceous argillite of the Palaeozoic Havallah pelagic sequence. The massive ore contains two generations of pyrite, a fine- and a coarse-grained variety; framboidal pyrite occurs in the surrounding carbonaceous argillite. Coarse grained pyrite is largely recrystallized fine-grained pyrite and is proportionately more abundant toward the margins of the lens. Chalcopyrite and sphalerite replace fine-grained pyrite and vein-fragmented coarse-grained pyrite. Quartz fills openings in the sulphide fabric. S-isotope data are related to sulphide mineralogy and textures. Isotopically light S in the early fine-grained pyrite was probably derived from framboidal biogenic pyrite. The S-isotope values of the later coarse-grained pyrite and chalcopyrite probably reflect a combination of reduced sea-water sulphate and igneous S. Combined S- and O-isotope and textural data accord with precipitation of fine-grained pyrite from a hydrothermal plume like those at the East Pacific Rise spreading centre at lat. 21oN. The primary material was recystallized and mineralized by later fluids of distinctly different S-isotope composition. -G.J.N.

  4. Neutrons and photons in materials research for thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Schorr, Susan [Institute of Geological Sciences, Freie Universitaet Berlin (Germany); Stephan, Christiane; Mainz, Roland; Rodriguez-Alvarez, Humberto; Tovar, Michael [Helmholtz-Zentrum Berlin fuer Materialien und Energie (Germany)

    2011-08-15

    The understanding of the interplay between structural and electronic properties of photovoltaic materials as well as a deeper insight into growth pathways and phase formation kinetics of the absorber layer in a thin film solar cell give a crucial contribution to the continuous improvement of the solar cell efficiency. Among the various experimental methods used for the investigation of the structure and microstructure of photovoltaic materials, neutron, and X-ray (photon) scattering are key techniques of choice. Both techniques are complementary, which is demonstrated in the present paper. Neutron powder diffraction is used to detect different kinds of intrinsic point defects in chalcopyrite type and kesterite type semiconductors. The calculated defect concentrations may lead to the expectation of a clustering of anti-site defects and vacancy to the electrical inactive defect pairs (2V{sub Cu}+In{sub Cu}) and (In{sub Cu}+Cu{sub In}). By the means of energy dispersive X-ray diffraction (EDXRD) phase formations and grain growth in thin films are studied in real time. The potential of EDXRD for in situ studies of reactions during the formation of chalcopyrite thin films is demonstrated. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  5. Bioremediation of toxic heavy metals using acidothermophilic autotrophes.

    Science.gov (United States)

    Umrania, Valentina V

    2006-07-01

    Investigations were carried out to isolate microbial strains from soil, mud and water samples from metallurgically polluted environment for bioremediation of toxic heavy metals. As a result of primary and secondary screening various 72 acidothermophilic autotrophic microbes were isolated and adapted for metal tolerance and biosorption potentiality. The multi-metal tolerance was developed with higher gradient of concentrations of Ag, As, Bi, Cd, Cr, Co, Cu, Hg, Li, Mo, Pb, Sn and Zn. The isolates were checked for their biosolubilization ability with copper containing metal sulfide ores. In case of chalcopyrite 85.82% and in covellite as high as 97.5% copper solubilization occurred in presence of 10(-3) M multi-heavy metals on fifth day at 55 degrees C and pH 2.5. Chemical analyses were carried out by inductively coupled plasma spectroscopy (ICP) for metal absorption. The selected highly potential isolate (ATh-14) showed maximum adsorption of Ag 73%, followed by Pb 35%, Zn 34%, As 19%, Ni 15% and Cr 9% in chalcopyrite.

  6. Bioflotation of sulfide minerals with Acidithiobacillus ferrooxidans in relation to copper activation and surface oxidation.

    Science.gov (United States)

    Pecina-Treviño, E T; Ramos-Escobedo, G T; Gallegos-Acevedo, P M; López-Saucedo, F J; Orrantia-Borunda, E

    2012-08-24

    Surface oxidation of sulfides and copper (Cu) activation are 2 of the main processes that determine the efficiency of flotation. The present study was developed with the intention to ascertain the role of the phenomena in the biomodification of sulfides by Acidithiobacillus ferrooxidans culture (cells and growth media) and their impact in bioflotation. Surface characteristics of chalcopyrite, sphalerite, and pyrrhotite, alone and in mixtures, after interaction with A. ferrooxidans were evaluated. Chalcopyrite floatability was increased substantially by biomodification, while bacteria depressed pyrrhotite floatability, favoring separation. The results showed that elemental sulfur concentration increased because of the oxidation generated by bacterial cells, the effect is intensified by the Fe(III) left in the culture and by galvanic contact. Acidithiobacillus ferrooxidans culture affects the Cu activation of sphalerite. The implications of elemental sulfur concentration and Cu activation of sphalerite are key factors that must be considered for the future development of sulfide bioflotation processes, since the depressive effect of cells could be counteracted by elemental sulfur generation.

  7. Sudden stress relaxation in compound semiconductor thin films triggered by secondary phase segregation

    Science.gov (United States)

    Mainz, R.; Rodriguez-Alvarez, H.; Klaus, M.; Thomas, D.; Lauche, J.; Weber, A.; Heinemann, M. D.; Brunken, S.; Greiner, D.; Kaufmann, C. A.; Unold, T.; Schock, H.-W.; Genzel, C.

    2015-10-01

    In polycrystalline compound semiconductor thin films, structural defects such as grain boundaries as well as lateral stress can form during film growth, which may deteriorate their electronic performance and mechanical stability. In Cu-based chalcogenide semiconductors such as Cu (In ,Ga ) Se2 or Cu2ZnSn (S,Se ) 4 , temporary Cu excess during film growth leads to improved microstructure such as a reduced grain boundary density, a strategy that has been used for decades for high-efficiency chalcopyrite thin film solar cells. However, the mechanisms responsible for the beneficial effect of Cu excess are yet not fully clarified. Here, we investigate the evolution of lateral stress, grain growth, and Cu-Se segregation during Cu-Se deposition onto Cu-poor CuInSe2. Real-time x-ray diffraction and fluorescence analysis with a double-detector setup reveals that sudden stress relaxation occurs shortly prior to Cu-Se segregation at the surface and precisely coincides with domain growth and change of texture. Numerical reaction-diffusion modeling provides an explanation for the observed delay of Cu-Se segregation. Our results show that partial recrystallization of the film can be already reached without the necessity of an overall Cu-rich film composition and thus suggest a new synthesis route for the fabrication of high-quality chalcopyrite absorber films.

  8. Compound semiconductor alloys: From atomic-scale structure to bandgap bowing

    Energy Technology Data Exchange (ETDEWEB)

    Schnohr, C. S., E-mail: c.schnohr@uni-jena.de [Institut für Festkörperphysik, Friedrich-Schiller-Universität Jena, Max-Wien-Platz 1, 07743 Jena (Germany)

    2015-09-15

    Compound semiconductor alloys such as In{sub x}Ga{sub 1−x}As, GaAs{sub x}P{sub 1−x}, or CuIn{sub x}Ga{sub 1−x}Se{sub 2} are increasingly employed in numerous electronic, optoelectronic, and photonic devices due to the possibility of tuning their properties over a wide parameter range simply by adjusting the alloy composition. Interestingly, the material properties are also determined by the atomic-scale structure of the alloys on the subnanometer scale. These local atomic arrangements exhibit a striking deviation from the average crystallographic structure featuring different element-specific bond lengths, pronounced bond angle relaxation and severe atomic displacements. The latter, in particular, have a strong influence on the bandgap energy and give rise to a significant contribution to the experimentally observed bandgap bowing. This article therefore reviews experimental and theoretical studies of the atomic-scale structure of III-V and II-VI zincblende alloys and I-III-VI{sub 2} chalcopyrite alloys and explains the characteristic findings in terms of bond length and bond angle relaxation. Different approaches to describe and predict the bandgap bowing are presented and the correlation with local structural parameters is discussed in detail. The article further highlights both similarities and differences between the cubic zincblende alloys and the more complex chalcopyrite alloys and demonstrates that similar effects can also be expected for other tetrahedrally coordinated semiconductors of the adamantine structural family.

  9. Hydrothermal Evolution of the Giant Cenozoic Kadjaran porphyry Cu-Mo deposit, Tethyan metallogenic belt, Armenia, Lesser Caucasus: mineral paragenetic, cathodoluminescence and fluid inclusion constraints

    Science.gov (United States)

    Hovakimyan, Samvel; Moritz, Robert; Tayan, Rodrik; Rezeau, Hervé

    2016-04-01

    The Lesser Caucasus belongs to the Central segment of the Tethyan metallogenic belt and it is a key area to understand the metallogenic evolution between the Western & Central parts of the Tethyan belt and its extension into Iran. Zangezur is the most important mineral district in the southernmost Lesser Caucasus. It is a component of the South Armenian block, and it was generated during the convergence and collision of the southern margin of the Eurasian plate and the northern margin of the Arabian plate, and terranes of Gondwana origin (Moritz et al., in press). The Zangezur ore district consists of the Tertiary Meghri-Ordubad composite pluton, which is characterized by a long-lasting Eocene to Pliocene magmatic, tectonic and metallogenic evolution. It hosts major porphyries Cu-Mo and epithermal Au - polymetallic deposits and occurrences, including the giant world class Kadjaran porphyry Cu-Mo deposit (2244 Mt reserves, 0.3% Cu, 0.05% Mo and 0.02 g/t Au). The Kadjaran deposit is hosted by a monzonite intrusion (31.83±0.02Ma; Moritz et al., in press). Detailed field studies of the porphyry stockwork and veins of the different mineralization stages, their crosscutting and displacement relationships and the age relationship between different paragenetic mineral associations were the criteria for distinction of the main stages of porphyry mineralization at the Kadjaran deposit. The economic stages being: quartz- molybdenite, quartz-molybdenite-chalcopyrite, and quartz-chalcopyrite. The main paragenetic association of the Kadjaran porphyry deposit includes pyrite, molybdenite, chalcopyrite, bornite, chalcocite, pyrrhotite, covellite, sphalerite, and galena. Recent field observations in the Kadjaran open pit revealed the presence of epithermal veins with late vuggy silica and advanced argillic alteration in the north-eastern and eastern parts of the deposit. They are distributed as separate veins and have also been recognized in re-opened porphyry veins and in

  10. Solvent effect in the synthesis of Cu–In–S and Cu–In–Se nanocrystals with tunable structure and composition

    Energy Technology Data Exchange (ETDEWEB)

    Gabka, Grzegorz; Leniarska, Klaudyna; Ostrowski, Andrzej [Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland); Malinowska, Karolina; Donten, Mikolaj [Faculty of Chemistry, University of Warsaw, Pasteura 1, 02-093 Warsaw (Poland); Bujak, Piotr, E-mail: piotrbujakchem@poczta.onet.pl [Faculty of Chemistry, Warsaw University of Technology, Noakowskiego 3, 00-664 Warsaw (Poland)

    2015-07-15

    The role of the solvent in the preparation of ternary CuInX{sub 2} (X = S or Se) nanocrystals was investigated. It was found that the use of oleylamine as a solvent with copper(II) oleate, indium(III) acetate diphenyl diselenide as precursors yields copper-rich, wurtzite-type Cu{sub 2.0}In{sub 1.0}Se{sub 2.5} (2Cu{sub 2}Se–In{sub 2}Se{sub 3}) nanocrystals which after size sorting exhibit the quantum confinement effect. Changing oleylamine for 1-octadecene, while keeping the same set of precursors and reaction conditions, results in the formation of indium-rich chalcopyrite nanocrystals Cu{sub 1.0}In{sub 1.8}Se{sub 3.2} (Cu{sub 2}Se-1.8 In{sub 2}Se{sub 3}). The differences in the stoichiometry can be rationalized on the basis of stronger reducing properties of oleylamine which more effectively reduces Cu(II) to Cu(I) in the reaction medium. Stoichiometric chalcopyrite CuInSe{sub 2} nanocrystals can be obtained in the same conditions by exchanging diphenyl diselenide for the Woollins' reagent, never previously applied to the preparation of Cu–In–Se nanocrystals. In the case of Cu–In–S nanocrystals the chemical composition is governed not by the type of the solvent but by the reducing properties of 1-dodecanethiol, the precursor of sulfur. Independently of the solvent copper-rich nanocrystals are obtained of either wurtzite-type Cu{sub 1.6}In{sub 1.0}S{sub 2.3} (1.6 Cu{sub 2}S–In{sub 2}S{sub 3}) in 1-octadecene or chalcopyrite-type Cu{sub 1.8}In{sub 1.0}S{sub 2.4} (1.8 Cu{sub 2}S–In{sub 2}S{sub 3}) in oleylamine. - Graphical abstract: Display Omitted - Highlights: • The role of the solvent in the preparation of ternary nanocrystals was investigated. • OLA yields wurtzite-type Cu{sub 2.0}In{sub 1.0}Se{sub 2.5} and chalcopyrite-type Cu{sub 1.8}In{sub 1.0}S{sub 2.4.} • ODE yields chalcopyrite-type Cu{sub 1.0}In{sub 1.8}Se{sub 3.2} and wurtzite-type Cu{sub 1.6}In{sub 1.0}S{sub 2.3}.

  11. Preparation and characterization of CuInSe{sub 2} nanoparticles elaborated by novel solvothermal protocol using DMF as a solvent

    Energy Technology Data Exchange (ETDEWEB)

    Ben Marai, A., E-mail: Achraf.Benmarai@promes.cnrs.fr [Laboratoire Procédés, Matériaux et Energie Solaire, PROMES-CNRS, Tecnosud, Rambla de la thermodynamique, 66100 Perpignan (France); Laboratoire de Physique des Matériaux et des Nanomatériaux appliquée à l' Environnement, LaPhyMNE, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès (Tunisia); Djessas, K. [Laboratoire Procédés, Matériaux et Energie Solaire, PROMES-CNRS, Tecnosud, Rambla de la thermodynamique, 66100 Perpignan (France); Université de Perpignan, Via Domitia, 52 Avenue Paul Alduy, 68860, Perpignan Cedex9 (France); Ben Ayadi, Z.; Alaya, S. [Laboratoire de Physique des Matériaux et des Nanomatériaux appliquée à l' Environnement, LaPhyMNE, Université de Gabès, Faculté des Sciences de Gabès, Cité Erriadh Manara Zrig, 6072 Gabès (Tunisia)

    2015-11-05

    In this study, high purity and near stoichiometric CuInSe{sub 2} (CIS) nanoparticles have been successfully synthesized using solvothermal route. The goal of this paper is to improve the crystal quality while reducing production cost and limiting the toxicity of solvothermal reaction, as compared to processes including selenization step. Therefore, the starting solution solvothermal is constituted by the following precursors (CuSO{sub 4}.5H{sub 2}O, InCl{sub 3}.xH{sub 2}O and Se powder) which were dissolved in N, N Dimethylformamide (DMF) as solvent. A reasonable possible mechanism for the growth of CIS nanoparticles is proposed. The effect of process parameters on the synthesis and characterization of CIS nanoparticles were examined including reaction temperature (165–240 °C), process time (12–24 h) and the drying route. The as-obtained CIS nanoparticles are analyzed using diverse techniques such as x-ray diffraction (XRD), energy dispersive spectrometer (EDS), transmission electron microscopy (TEM), Raman spectroscopy and UV–vis-IR spectrophotometer. All results demonstrate that the optimal conditions for preparing a single-phase CIS obtained at 220 °C for 24 h and followed by annealing at 400 °C for 30 min under a nitrogen atmosphere. In addition, XRD results showed that the CIS nanoparticles crystallize in the chalcopyrite structure, with grain size in the order of 25 nm, which is also confirmed by TEM images. Raman spectra show the intense peak at 171 cm{sup −1}, which correspond to the chalcopyrite structure, no signature of secondary phases. Optical measurements revealed strong absorption in the entire visible light to near-infrared region and band gap (≈1.04 eV) is very close to those of absorbent materials in thin film solar cells. - Highlights: • Highly dispersed chalcopyrite CuInSe{sub 2} nanoparticles were successfully synthesized. • The DMF solvent act as both the solvent and the complexing agent. • Band gap was calculated to be 1

  12. Nature, origin and evolution of the granitoid-hosted early Proterozoic copper-molybdenum mineralization at Malanjkhand, Central India

    Science.gov (United States)

    Sarkar, S. C.; Kabiraj, S.; Bhattacharya, S.; Pal, A. B.

    1996-07-01

    At Malanjkhand, Central India, lode-type copper (-molybdenum) mineralization occurs within calcalkaline tonalite-granodiorite plutonic rocks of early Proterozoic age. The bulk of the mineralization occurs in sheeted quartz-sulfide veins, and K-silicate alteration assemblages, defined by alkali feldspar (K-feldspar≫albite)+dusty hematite in feldspar±biotite±muscovite, are prominent within the ore zone and the adjacent host rock. Weak propylitic alteration, defined by albite+biotite+epidote/zoisite, surrounds the K-silicate alteration zone. The mineralized zone is approximately 2 km in strike length, has a maximum thickness of 200 m and dips 65° 75°, along which low-grade mineralization has been traced up to a depth of about 1 km. The ore reserve has been conservatively estimated to be 92 million tonnes with an average Cu-content of 1.30%. Supergene oxidation, accompanied by limited copper enrichment, is observed down to a depth of 100 m or more from the surface. Primary ores consist essentially of chalcopyrite and pyrite with minor magnetite and molybdenite. δ34S (‰) values in pyrite and chalcopyrite (-0.38 to +2.90) fall within the range characteristic of granitoid-hosted copper deposits. δ18O (‰) values for vein quartz (+6.99 to +8.80) suggest exclusive involvement of juvenile water. Annealed fabrics are common in the ore. The sequence of events that led to the present state of hypogene mineralization is suggested to be as follows: fracturing of the host rock, emplacement of barren vein quartz, pronounced wall-rock alteration accompanied by disseminated mineralization and the ultimate stage of intense silicification accompanied by copper mineralization. Fragments of vein quartz and altered wall rocks and striae in the ore suggest post-mineralization deformation. The recrystallization fabric, particularly in chalcopyrite and sphalerite, is a product of dynamic recrystallization associated with the post-mineralization shearing. The petrology of the host

  13. Fluid inclusion evidence for hydrothermal fluid evolution in the Darreh-Zar porphyry copper deposit, Iran

    Science.gov (United States)

    Nateghi, Arash; Hezarkhani, Ardeshir

    2013-09-01

    The Darreh-Zar porphyry copper deposit is associated with a quartz monzonitic-granodioritic-porphyritic stock hosted by an Eocene volcanic sedimentary complex in which magmatic hydrothermal fluids were introduced and formed veins and alteration. Within the deepest quartz-rich and chalcopyrite-poor group A veins, LVHS2 inclusions trapped high salinity, high temperature aqueous fluids exsolved directly from a relatively shallow magma (0.5 kbar). These late fluids were enriched in NaCl and reached halite saturation as a result of the low pressure of magma crystallization and fluid exsolution. These fluids extracted Cu from the crystallizing melt and transported it to the hydrothermal system. As a result of ascent, the temperature and pressure of these fluids decreased from 600 to 415 °C, and approximately 500-315 bars. At these conditions, K-feldspar and biotite were stabilized. Type A veins were formed at a depth of ∼1.2 km under conditions of lithostatic pressure and abrupt cooling. Upon cooling and decompressing, the fluid intersected with the liquid-vapor field resulting in separation of immiscible liquid and vapor. This stage was recorded by formation of LVHS1, LVHS3 and VL inclusions. These immiscible fluids formed chalcopyrite-pyrite-quartz veins with sericitic alteration envelopes (B veins) under the lithostatic-hydrostatic pressure regime at temperatures between 415 and 355 °C at 1.3 km below the paleowater table. As the fluids ascended, copper contents decreased and these fluids were diluted by mixing with the low salinity-external fluid. Therefore, pyrite-dominated quartz veins were formed in purely hydrostatic conditions in which pressure decreased from 125 bars to 54 bars and temperature decreased from 355 to 298 °C. During the magmatic-hydrothermal evolution, the composition and P-T regime changed drastically and caused various types of veins and alterations. The abundance of chalcopyrite precipitation in group B veins suggests that boiling and

  14. Gold-silver-tellurium mineral assemblages in different ore styles of the Southern Urals VHMS deposits

    Science.gov (United States)

    Maslennikov, V. V.; Zaykov, V. V.; Maslennikova, S. P.; Tesalina, S. G.; Herrington, R. J.; Buschmann, B.; Becker, K.; Petersen, S.; Orgeval, J. J.; Leistel, M.

    2003-04-01

    VMS deposits of the South Urals generally show a continuum in degradation and reworking ranging from pristine steep-sided hydrothermal sulphide mounds to deposits dominated by layered strata of clastic sulphides. Four different deposits with varying degrees of degradation in order of increased reworking: (Yaman-Kasy longrightarrow Molodezhnoe longrightarrow Alexandrinskoe longrightarrow Balta-Tau) have been ranged. The influence of sulphide mound destruction and of sea-floor alteration on mineral assemblages was investigated In the pristine Yaman-Kasy sulphide mound gold and silver occur as altaite+tellurium+hessite-stuetzite+sylvanite and later galena+native gold+pyrite assemblages in chalcopyrite+isocubanite-rich linings of former chimney conduits. Chalcopyrite-dominated conduit fragments in clastic ore facies contain native tellurium+gold intergrowths. In the weakly reworked Molodezhnoe deposit gold-silver assemblages only occur in sea-floor altered clastic sulphides on the slope of massive sulphide mounds in bornite- and tennantite-rich ores in association with Cu-Ag sulfides such as jalpaite, mckinstryite, and stromeyerite and rare Au-Ag-tellurides (petzite). The Alexandrinskoe deposit is dominated by clastic ores and here native gold and rare hessite occur together with galena in tennantite-sphalerite-dominated veins of the footwall as well as in drusy sphalerite forming conduits of vent chimneys. An assemblage of electrum+galena+tennantite was observed in secondary chalcopyrite in the outer walls of chimneys. Native gold+stromeyerite are common in bornite-rich clastic sulphides while an assemblage of Ag-sulphosalts+electrum is common in barite-rich ores. In the reworked Balta-Tau deposit Ag-sulphosalts+electrum-kustelite occur often together with tennantite+galena+barite banded ores. Gold-silver-telluride mineralisation in these VMS deposits changes with degree of reworking from Au-tellurides, and native gold+galena+pyrite in pristine sulphide mounds to

  15. The case for metamorphic base metal mineralization: pyrite chemical, Cu and S isotope data from the Cu-Zn deposit at Kupferberg in Bavaria, Germany

    Science.gov (United States)

    Höhn, S.; Frimmel, H. E.; Debaille, V.; Pašava, J.; Kuulmann, L.; Debouge, W.

    2017-01-01

    The stratiform Cu-Zn sulfide deposit at Kupferberg in Germany represents Bavaria's largest historic base metal producer. The deposit is hosted by Early Paleozoic volcano-sedimentary strata at the margin of a high-grade allochthonous metamorphic complex. The present paper reports on the first Cu and S isotope data as well as trace element analyses of pyrite from this unusual deposit. The new data point to syn-orogenic mineralization that was driven by metamorphic fluids during nappe emplacement. Primary Cu ore occurs as texturally late chalcopyrite within stratiform laminated pyrite in black shale in two different tectonostratigraphic units of very low and low metamorphic grade, respectively, that were juxtaposed during the Variscan orogeny. Trace element contents of different pyrite types suggest the presence of at least one hydrothermal pyrite generation (mean Co/Ni = 35), with the other pyrite types being syn-sedimentary/early diagenetic (mean Co/Ni = 3.7). Copper isotope analyses yielded a narrow δ65Cu range of -0.26 to 0.36‰ for all ore types suggesting a hypogene origin for the principal chalcopyrite mineralization. The ore lenses in the two different tectonostratigraphic units differ with regard to their δ34S values, but little difference exists between poorly and strongly mineralized domains within a given locality. A genetic model is proposed in which syn-sedimentary/early diagenetic pyrite with subordinate chalcopyrite and sphalerite formed in black shale beds in the two different stratigraphic units, followed by late-tectonic strata-internal, hydrothermal mobilization of Fe, Cu, and Zn during syn-orogenic thrusting, which concentrated especially Cu to ore grade. In agreement with this model, Cu distribution in stream sediments in this region shows distinct enrichments bound to the margin of the allochthonous complex. Thus, Kupferberg can be considered a rare example of a syn-orogenic Cu deposit with the Cu probably being derived from syn

  16. Sulfide composition and microthermometry of fluid inclusions in the leg 111 sheeted dike section of Ocean Drilling Program hole 504B, Costa Rica rift

    Energy Technology Data Exchange (ETDEWEB)

    Schoeps, D. (Technische Hochschule Aachen (West Germany)); Herzig, P.M. (Univ. of Toronto, Ontario (Canada))

    1990-06-10

    Hole 504B of the Ocean Drilling Program is dedicated to the study of crustal structure and hydrothermal processes in 5.9-m.y.-old oceanic basement. Continuing the work of previous legs, hole 504B was extended 212.3 m to a total depth of 1,562.3 m below seafloor (bsf) during leg 111 in 1986. Quartz-sulfide veins occur at a depth of 1,369-1,388 m bsf in basalts of the sheeted dike complex. The ore minerals are predominantly pyrite, less chalcopyrite, rare Co-rich Cu-Fe-S phases, and a thiospinel (linnaeite/carrollite). Microprobe analyses yield a high Co content in zoned vein pyrites (>8 wt%) as well as in the Cu-Fe-S phases (>5 wt%). Up to 35.8 wt% CO was detected in the thiospinel. A Co/Ni ratio of > 100 distinguishes the vein pyrite from pyrite in the basaltic wall rock and from pyrite formed as an alteration product of olivine (Co/Ni < 5). The Co/Ni ratios correlate positively with Cu and negatively with As. Co-rich, nonstoichiometric Cu-Fe-S sulfides in chalcopyrite are interpreted as metastable phases which have been quenched at a high temperature and prohibited from exsolution of the stable products chalcopyrite and pyrite. Fluid inclusions in quartz from the quartz-sulfide veins are two-phase and vary from liquid- to vapor-dominated. Their salinities range from 4.2 to 7.2 wt% equivalent NaCl and average 5.5 wt%. Pressure (360 bars) corrected average filling temperatures vary from 271 to 408 C with a maximum of 486 C. This is consistent with calculated quartz formation temperatures for a single quartz separate (+4.2{per thousand} {delta}{sup 18}O) using oxygen isotope thermometry. The {delta}{sup 18}O value of the hydrothermal fluid was determined to be +1.7{per thousand}. The temperature data indicate fluid alteration of the sheeted dikes at about 350 to 500 C.

  17. First-principles study of electronic structure of CuSbS{sub 2} and CuSbSe{sub 2} photovoltaic semiconductors

    Energy Technology Data Exchange (ETDEWEB)

    Maeda, T., E-mail: tmaeda@ad.ryukoku.ac.jp; Wada, T.

    2015-05-01

    We studied the features of CuSbS{sub 2} (CAS) and CuSbSe{sub 2} (CASe), two proposed photovoltaic compounds, and clarified their electronic structures by first-principles calculations and compared them to the chalcopyrite-type CuInSe{sub 2} results. For both CAS and CASe, the calculated enthalpies of formation of the chalcostibite phases were considerably lower than those of the chalcopyrite phases. Therefore, we considered that the chalcostibite phase is more stable for CAS and CASe. In their band structure calculated with the HSE06 hybrid functional, the valence band maxima of CAS and CASe were located at the Γ-point, and the conduction band minima were located at the R-point. Their second lowest conduction band was located at the Γ-point, whose energy level nearly equaled the R-point. For CAS (CASe), the partial density of the states shows the character of the Cu 3d and S 3p (Se 4p) orbitals at the top of the valence bands and the Sb 5p and S 3p (Se 4p) orbitals at the bottom of the conduction bands. The conduction bands of CAS and CASe have a p-orbital character (Sb 5p) that differs from the s-orbital character (In 5s) of CuInSe{sub 2}. It is for the reason that CAS and CASe do not have a chalcopyrite structure but a chalcostibite-type structure. The calculated absorption coefficient of CuSbS{sub 2} (10{sup 4}-10{sup 5} cm{sup −1}) is comparable to that of CuInSe{sub 2}. - Highlights: • We studied the features of CuSbS{sub 2} and CuSbSe{sub 2}, newly proposed photovoltaic compounds. • Chalcostibite phase is more stable in CuSbS{sub 2} and CuSbSe{sub 2}. • Band structures of CuSbS{sub 2} and CuSbS{sub 2} were calculated with HSE06 hybrid functional. • Absorption coefficient of chalcostibite-type CuSbS{sub 2} is comparable to that of CuInSe{sub 2}.

  18. Sulfur isotope evidence for penetration of MVT fluids into igneous basement rocks, southeast Missouri, USA

    Science.gov (United States)

    Shelton, K. L.; Burstein, I. B.; Hagni, R. D.; Vierrether, C. B.; Grant, S. K.; Hennigh, Q. T.; Bradley, M. F.; Brandom, R. T.

    1995-08-01

    Previous studies of galena and sphalerite from Paleozoic MVT deposits in the Viburnum Trend, southeast Missouri documented large variations in δ34S values throughout the ore-forming event. The present study of Cu-Fe-sulfides reveals a similar δ34S variation that reflects two end-member sulfur reservoirs whose relative importance varied both temporally and spatially. More 34S-enriched sulfides (δ34S approaching 25‰) indicate introduction of sulfur from basinal sedimentary sources, whereas more 32S-enriched sulfides (δ34S Precambrian, igneous-hosted FeCu mineralization in southeast Missouri (West and Central Domes of Boss-Bixby) were investigated to elucidate their relationship to Cu-rich MVT orebodies hosted nearby within the overlying Cambrian Bonneterre Dolomite. Mineralization at Boss-Bixby is composed of an early phase of iron oxide deposition followed by Cu-Fe-sulfides. The Central Dome is faulted and its mineralization is more fracture-controlled than the typically podiform ores of the West Dome. The δ34S values of West Dome sulfides are 0.9 to 6.5‰ and pyrite-chalcopyrite indicate a temperature of 525° ± 50 °C. These data indicate an igneous source of sulfur during Precambrian ore deposition. In contrast, δ34S values of Central Dome sulfides are 9.4 to 20.0‰ and pyrite-chalcopyrite indicate temperatures of 275° ± 50 °C. Similar δ34S values are obtained for chalcopyrite from the overlying MVT deposits. We speculate that deeply circulating, basin-derived MVT fluids mobilized sulfur and copper from the underlying igneous basement and redeposited them in overlying Curich MVT orebodies, as well as overprinting earlier Precambrian sulfides of the Central Dome with a later, Paleozoic MVT sulfur isotope signature. Many models for MVT fluid circulation in the Midcontinent region of North America assume that igneous basement rocks are an impermeable boundary, but in southeast Missouri, evidence exists for structurally controlled MVT fluid movement

  19. Disseminated, veinlet and vein Pb-Zn, Cu and Sb polymetallic mineralization in the GaleChah-Shurab mining district, Iranian East Magmatic Assemblage (IEMA

    Directory of Open Access Journals (Sweden)

    Behzad Mehrabi

    2011-04-01

    Full Text Available The Iranian East Magmatic Assemblage (IEMA in the Central Lut region, hosted porphyry and vein-type polymetallic mineralization. The GaleChah-Shurab mining district is located in NW of the IEMA. Volcanic and subvolcanic bodies in the area are composed of calc-alkaline porphyry quartz-latite, porphyry dacite and rhyodacite and hornblende-biotite andesite, equivalent to I-type granite. They emplaced in Tertiary and intruded the Jurassic shale, siltstone and limestone basement (Shemshak Fm. The faults, joints and fractures, are the main controls on the mineralization, in forms of disseminated, vein, veinlet and minor stockwork and brecciation type mineralization of Pb, Zn, Cu, Sb and trace elements. Vein and veinlet of Pb+Zn±Cu±Sb in the Gale-Chah abandoned mine accompanied by carbonate and silicic alterations in association with galena, sphalerite, pyrite, chalcopyrite, bournonite and tetrahedrite as the hypogene ore minerals and their supergene products including cerussite, covellite, digenite and second-generation colloidal pyrite. The Pb+Zn+Cu+Sb mineralization associated with sericitic and silicic alterations in the Shurab abandoned mine, is composed of two types of mineralization, veinlet and brecciation vein in the porphyry dacite boundaries with Jurassic shale and sandstones, and the disseminated and disseminated-veinlet mineralization which is hosted by the altered porphyry dacite and rhyodacite intrusive rocks. The mineral assemblages are galena, sphalerite, stibnite, As-bearing pyrite, chalcopyrite and tetrahedrite-tennantite complex hypogene-sulfide ore as a hypogene ore, and malachite, covellite, cerussite and melancoitic pyrite as a sulfide-oxide supergene ore. The Pb+Zn+Sb±As±Ag polymetallic occurrence is associated with sericitic, carbonate and chloritic alteration assemblage in the Chupan occurrence, in two forms, I vein, veinlet-stockwork (30m depth confined to fault structures and II disseminated-replacement (below 70m mainly

  20. Chemical and mineralogical data of the metalliferous mineralization from S. Carlo mine (Peloritani mts, Ne Sicily, Italy

    Directory of Open Access Journals (Sweden)

    Pisacane, G

    2006-05-01

    Full Text Available The mineralization processes in the Peloritani Belt (Southern Sector of the Calabria- Peloritani Arc prevalently developed during the Variscan orogenesis producing Pb, Zn, Fe, As, Sb, Cu, Ag, W, etc. polymetalliferous ore-bearing horizons. This paper focuses on the polymetalliferous mineralization recognised in the ancient S. Carlo Mine, which has already been subject of some studies and is part of an important discordant vein deposits system that are widespread in the Mandanici Unit (MaU. This Unit is characterized by a Variscan low-P, polyphasic and plurifacial metamorphic basement, exhibiting a prograde zoning, from chlorite zone of greenschist facies to oligoclase-almandine zone of amphibolite facies. The Variscan main foliation (Fv2 is irregularly cut by mineralized veins of decimetric to metric width. They are also perpendicular to the Alpine mylonitic shear zones of metric thickness developing along the sub-horizontal tectonic contacts between the tectono-stratigraphic units. These vein deposits formed along late-Alpine systems of fractures and faults, after Peloritani nappe emplacement. Minerographic study reveals a metalliferous mineral association mainly composed of tetrahedrite associated with, in order of decreasing abundance, chalcopyrite, bournonite, pentlandite, stromeyerite, arsenopyrite, scheelite, galena, sphalerite, pyrite, bismuthinite, boulangerite, jamesonite, covellite, bornite and argentite. Quartz, siderite and ankerite among non-metalliferous minerals are predominant. This work has been supported by mineralogical studies and chemical analyses carried out by Atomic Absorption and Inductively Coupled Plasma-Mass Spectrometry on powdered and separated samples of minerals. Geochemical data (major and trace elements have allowed a detailed characterization of the minerals. They have revealed that the most significant minerals with Au contents around 1 ppm are tetrahedrite, sphalerite, chalcopyrite and bournonite. The

  1. Control over the preferred orientation of CIGS films deposited by magnetron sputtering using a wetting layer

    Science.gov (United States)

    Yan, Yong; Jiang, Fan; Liu, Lian; Yu, Zhou; Zhang, Yong; Zhao, Yong

    2016-01-01

    A growth method is presented to control the preferred orientation in chalcopyrite CuIn x Ga1- x Se2 (CIGS) thin films grown by magnetron sputtering. Films with (220/204) and (112) preferred orientation as well as randomly oriented films were prepared. The effects of an In2Se3 wetting layer and the working pressure on the texture transition phenomena were examined. A large-grained CIGS film with (220/204) texture was formed at 400°C with the inclusion of a thin (80 nm) In2Se3 layer and liquid phase (excess copper selenide phase) formation, and the reaction mechanism is proposed. The device deposited at 2.0 Pa on an In2Se3 layer exhibited the optimal electrical properties. [Figure not available: see fulltext.

  2. PGE patterns of ores of Dajing Cu-polymetallic deposit in Linxi County, Inner Mongolia: Indicator to source of metallogenic elements

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    By comparing PGE patterns of sulfide ores with that of basic-ultrabasic dikes occurring in the Dajing Cu-polymetallic deposit, we discover that there are similar positive slopes between the basic-ultrabasic dikes and the black ores composed mainly of sphalerite and galena, reflecting affinity of their source. The PGE patterns of the yellow ores composed basically of chalcopyrite, arsenopyrite and pyrite are actually different. One is close to the pattern of the mantle lherzolite, and others resemble the pattern of the basic rocks. However, the concentrations of Ru are higher in the yellow ores, reflecting that sulfur attains or approaches saturation in their parent magma. The PGE characteristics of ores and dikes show that the magmas derived from the deep of crust and the metallogenic elements were supplied mainly by growth material of the crust. In addition, the mantle-derived magma also offered some elements.

  3. Colloidal-chemistry based synthesis of quantized CuInS2/Se2 nanoparticles

    Directory of Open Access Journals (Sweden)

    Abazović Nadica D.

    2012-01-01

    Full Text Available Ternary chalcogenide nanoparticles, CuInS2 and CuInSe2, were synthesized in high- temperature boiling organic non-polar solvent. The X-ray diffraction analysis revealed that both materials have tetragonal (chalcopyrite crystal structure. Morphology of the obtained materials was revealed by using transmission electron microscopy. Agglomerated spherical CuInS2 nanoparticles with broad size distribution in the range from 2 to 20 nm were obtained. In the case of CuInSe2, isolated particles with spherical or prismatic shape in the size range from 10 to 25 nm were obtained, as well as agglomerates consisting of much smaller particles with diameter of about 2-5 nm. The particles with the smallest diameters of both materials exhibit quantum size effect.

  4. Cu isotope variability in Bavariás largest Cu-Zn deposit in Kupferberg (NE Bavaria, Germany)

    Science.gov (United States)

    Höhn, Stefan; Frimmel, Hartwig E.; Debaille, Vinciane; Debouge, Wendy

    2016-04-01

    Kupferberg, a small town c. 15 km northeast of Kulmbach, owns its existence to Bavaria's largest Cu-Zn deposit, which was mined intermittently from the 13th to the 19th century. The deposit is located in the Saxothuringian Zone of the Variscan basement in northeastern Bavaria. It is positioned between the allochthonous Münchberg metamorphic complex in the east and a major northwest-southeast tending regional fault zone, the "Franconian Lineament", in the west. The deposit is hosted by an Early Palaeozoic volcano-sedimentary succession of the Randschiefer Formation (RF) and consists of a northwest-southeast directed string of several stratiform, sulfide-rich ore lenses. These lenses show a remarkably simple mineralogy dominated by quartz, carbonate, pyrite and chalcopyrite with minor amounts of sphalerite and chlorite. The genesis of the Cu-Zn mineralization has remained speculative. A purely syngenetic model, supported by the generally laminated appearance of the ore, has to be questioned because of the ore lenses occurring in different tectonic units. Urban & Vaché (1972) proposed supergene enrichment between the Cretaceous and the Tertiary as most critical. To test such a supergene versus hypogene Cu-mineralization, we investigated the Cu isotopic composition of primary and secondary Cu phases as well as the trace element distribution in three pyrite generations. The pyrite generation that is coeval with the principal Cu-mineralization in the form of chalcopyrite has Co/Ni ratios (on average 35) typical of hydrothermal, possibly metamorphic, formation. Chalcopyrite, present at highly variable modal proportions, yielded a narrow range in δ65Cu from -0.26 to 0.36 ‰Ḃoth the absolute values and the narrow range are similar to the δ65Cu range known for hydrothermal chalcopyrite in crustal rocks (Markl et al. 2006). Metamorphism has been shown to further restrict the range in δ65Cu (Ikehata et al. 2011) - an effect that might be applicable to Kupferberg. In

  5. Magnetic influence on the unidentified luminous phenomena in Hessdalen, Norway

    Science.gov (United States)

    Gitle Hauge, Bjørn; Kjøniksen, Anna-Lena; Petter Strand, Erling; Zlotnicki, Jaques; Vargemezis, George

    2016-04-01

    Unidentified luminous phenomena have been observed in the low atmosphere over the Hessdalen valley for decades. First scientific investigation was done by E.Strand in 1984, where spiral movements of lights was recorded. The Science Camp program has conducted yearly field investigations since 2002 and has confirmed the existence of this spiral-behavior. (http://sciencecamp.no) Such behavior has also been documented in Alabama, USA. In September 2015 spiral like movement of lights was observed together with the more common spherical lights. This spiral movement indicates the presence of low atmospheric charged matter, moving in a magnetic field. A geological survey in 2014 reviled the presence of strong magnetic anomalies. The valley contains several abandoned copper mines containing Chalcopyrite and Magnetite. The Magnetite was not useful in the copper production, and left in heaps around the valley unused. This may contribute to the magnetic anomalies in the valley.

  6. Synthesis of CuInSe2 thin films from electrodeposited Cu11In9 precursors by two-step annealing

    Directory of Open Access Journals (Sweden)

    TSUNG-WEI CHANG

    2014-02-01

    Full Text Available In this study, copper indium selenide (CIS films were synthesized from electrodeposited Cu-In-Se precursors by two-step annealing. The agglomeration phenomenon of the electrodeposited In layer usually occurred on the Cu surface. A thermal process was adopted to turn Cu-In precursors into uniform Cu11In9 binary compounds. After deposition of the Se layer, annealing was employed to form chalcopyrite CIS. However, synthesis of CIS from Cu11In9 requires sufficient thermal energy. Annealing temperature and time were investigated to grow high quality CIS film. Various electrodeposition conditions were investigated to achieve the proper atomic ratio of CIS. The properties of the CIS films were characterized by scanning electron microscopy (SEM, X-ray Diffraction (XRD, and Raman spectra.

  7. Multiple hydrothermal and metamorphic events in the Kidd Creek volcanogenic massive sulphide deposit, Timmins, Ontario: evidence from tourmalines and chlorites

    Science.gov (United States)

    Slack, J.F.; Coad, P.R.

    1989-01-01

    The tourmalines and chlorites record a series of multiple hydrothermal and metamorphic events. Paragenetic studies suggest that tourmaline was deposited during several discrete stages of mineralization, as evidence by brecciation and cross-cutting relationships. Most of the tourmalines have two concentric growth zones defined by different colours (green, brown, blue, yellow). Some tourmalines also display pale discordant rims that cross-cut and embay the inner growth zones and polycrystalline, multiple-extinction domains. Late sulphide veinlets (chalcopyrite, pyrrhotite) transect the inner growth zones and pale discordant rims of many crystals. The concentric growth zones are interpreted as primary features developed by the main ore-forming hydrothermal system, whereas the discordant rims, polycrystalline domains, and cross-cutting sulphide veinlets reflect post-ore metamorphic processes. Variations in mineral proportions and mineral chemistry within the deposit mainly depend on fluctuations in temperature, pH, water/rock ratios, and amounts of entrained seawater. -from Authors

  8. Electrochemical corrosion of grinding media and effect of anions present in industrial waters; Corrosion electroquimica de medios de molienda y efecto de aniones presentes en aguas industriales

    Energy Technology Data Exchange (ETDEWEB)

    Magne, L.; Navarro, P.; Vargas, C.; Carrasco, S.

    2001-07-01

    The steel used in the minerals processing as grinding media (balls or bars), is an important input in terms of cost of the process. Considering the importance of the steel consumption in these processes, this work is guided to evaluate to laboratory scale the effect of the anions present in the industrial waters on the electrochemical corrosion of grinding media. Tests in electrochemical cell, were accomplished measuring potential and corrosion current to four electrodes that were manufactured using sufficiently pure sample of chalcopyrite, bornite, enargite and steel ball. The ions used in the tests were chlorides, sulfates, nitrates and carbonates in concentrations from 1 to 180 ppm in individual form or in mixtures, according to the levels measurement of these in industrial waters. (Author) 10 refs.

  9. Technological assessment of a mining-waste dump at the Dexing copper mine, China, for possible conversion to an in situ bioleaching operation.

    Science.gov (United States)

    Wu, Aixiang; Yin, Shenghua; Wang, Hongjiang; Qin, Wenqin; Qiu, Guanzhou

    2009-03-01

    In order to extract copper metal from the waste dump of Dexing copper mine and resolve the environmental problems caused by acidic water and heavy metals, a dump bioleaching plant was designed based on a series of experimental investigations. The investigation shown that the low-grade of the dump, refractoriness of chalcopyrite, leakage of pad, small Acidithiobacillus population and low dump permeability are the main factors that contribute to the challenges faced by the plant. Stability of the high and steep slope of the dump is the other hidden danger to which much attention is not paid. To evaluate the potential unstability of the dump, the leaching process, ore surface erosion, particle size, chemical elements and mechanical properties of the waste rock in DCM were investigated through experiment in this paper.

  10. Electronic structure of the Zn(O,S)/Cu(In,Ga)Se2 thin-film solar cell interface

    Energy Technology Data Exchange (ETDEWEB)

    Mezher, Michelle [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Garris, Rebekah [National Renewable Energy Laboratory (NREL), Golden CO 80401 USA; Mansfield, Lorelle M. [National Renewable Energy Laboratory (NREL), Golden CO 80401 USA; Horsley, Kimberly [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Weinhardt, Lothar [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen Germany; ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen Germany; Institute for Chemical Technology and Polymer Chemistry (ITCP), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe Germany; Duncan, Douglas A. [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Blum, Monika [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Rosenberg, Samantha G. [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Bär, Marcus [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Renewable Energy, Helmholtz-Zentrum Berlin für Materialien und Energie GmbH, 14109 Berlin Germany; Institut für Physik und Chemie, Brandenburgische Technische Universität Cottbus-Senftenberg, 03046 Cottbus Germany; Ramanathan, Kannan [National Renewable Energy Laboratory (NREL), Golden CO 80401 USA; Heske, Clemens [Department of Chemistry and Biochemistry, University of Nevada, Las Vegas (UNLV), Las Vegas NV 89154 USA; Institute for Photon Science and Synchrotron Radiation (IPS), Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen Germany; ANKA Synchrotron Radiation Facility, Karlsruhe Institute of Technology (KIT), 76344 Eggenstein-Leopoldshafen Germany; Institute for Chemical Technology and Polymer Chemistry (ITCP), Karlsruhe Institute of Technology (KIT), 76128 Karlsruhe Germany

    2016-03-10

    The electronic band alignment of the Zn(O,S)/Cu(In,Ga)Se2 interface in high-efficiency thin-film solar cells was derived using X-ray photoelectron spectroscopy, ultra-violet photoelectron spectroscopy, and inverse photoemission spectroscopy. Similar to the CdS/Cu(In,Ga)Se2 system, we find an essentially flat (small-spike) conduction band alignment (here: a conduction band offset of (0.09 +/- 0.20) eV), allowing for largely unimpeded electron transfer and forming a likely basis for the success of high-efficiency Zn(O,S)-based chalcopyrite devices. Furthermore, we find evidence for multiple bonding environments of Zn and O in the Zn(O,S) film, including ZnO, ZnS, Zn(OH)2, and possibly ZnSe.

  11. Porphyry-copper mineralisation in the central Srednogorie zone, Bulgaria

    Science.gov (United States)

    Strashimirov, Strashimir; Petrunov, Rumen; Kanazirski, Milko

    2002-08-01

    The porphyry-copper systems in the central part of the Srednogorie zone (Bulgaria) are represented by three major deposits (Elatsite, Medet and Assarel) and several smaller deposits and occurrences, all of them within the Panagyurishte ore district. The hydrothermal systems are related to Late Cretaceous calc-alkaline igneous complexes. Ore mineralisation is developed predominantly in the apical parts of subvolcanic and intrusive bodies as well as within the volcanic and basement metamorphic rocks. Several of the porphyry systems are spatially associated with shallow-level intermediate and high-sulphidation volcanic-hosted epithermal deposits of economic importance, such as the major gold-copper mine at Chelopech located 10 km from the Elatsite porphyry-copper deposit. Mineralisation processes in the porphyry deposits start with intensive hydrothermal alteration of the wall rocks. K-silicate alteration is characteristic for pre-ore hydrothermal activity in all of them, and it is located mostly in their central parts. Propylitic alteration is prominent in the Medet and Assarel deposits. The Assarel deposit is located in the central part of a palaeovolcanic structure and shows a large spectrum of pre-ore alterations, including propylitic, sericitic, and advanced argillic assemblages. The initial stages of the hydrothermal systems are characterised by high temperatures (>550-500 °C) and highly saline (50-20 wt% NaCl equiv.) and vapour-rich fluids of likely magmatic origin. The composition of the fluids gradually changes from H2O-NaCl±FeCl2 to H2O-NaCl-KCl and H2O-NaCl-dominated as the fluids cool, react with wall rocks, and may become diluted with meteoric water. Fe-Ti-oxide mineral associations were formed early in all deposits, later followed, in the Elatsite deposit, by an assemblage of bornite, chalcopyrite, platinum group element (PGE) phases, Co-Ni thiospinels, Ag- and Bi-tellurides, and selenides. The main ore stage in all deposits is dominated by

  12. Characterization of chemical bath deposited buffer layers for thin film solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Dwyer, D.; Efstathiadis, H.; Haldar, P. [College of Nanoscale Science and Engineering, University at Albany - State University of New York, 257 Fuller Rd., Albany, NY 12203 (United States); Sun, R. [Angstrom Sun Technologies Inc., 33 Nagog Park, Acton, MA 01720 (United States)

    2010-10-15

    Cadmium sulfide (CdS), indium sulfide (In{sub 2}S{sub 3}) and zinc sulfide (ZnS) thin films have been deposited by chemical bath deposition (CBD) for buffer layer applications in Cu-chalcopyrite-based thin film solar cells. Films were characterized by scanning electron microscopy (SEM), UV-Vis transmission, X-ray photoelectron spectroscopy (XPS), grazing-incidence X-ray diffraction (GIXRD), and spectroscopic ellipsometry. Results indicate CdS can be deposited with low oxygen content and high light transmission over 245-1700 nm. CBD-ZnS and CBD-InS both exhibit 5-10% less light transmission than CdS in the same thickness range. In terms of light transmission and degree of impurities CdS appears to be a better buffer material than CBD-ZnS or CBD-InS. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  13. Searching for new thermoelectric materials: some examples among oxides, sulfides and selenides

    Science.gov (United States)

    Hébert, S.; Berthebaud, D.; Daou, R.; Bréard, Y.; Pelloquin, D.; Guilmeau, E.; Gascoin, F.; Lebedev, O.; Maignan, A.

    2016-01-01

    Different families of thermoelectric materials have been investigated since the discovery of thermoelectric effects in the mid-19th century, materials mostly belonging to the family of degenerate semi-conductors. In the last 20 years, new thermoelectric materials have been investigated following different theoretical proposals, showing that nanostructuration, electronic correlations and complex crystallographic structures (low dimensional structures, large number of atoms per lattice, presence of ‘rattlers’…) could enhance the thermoelectric properties by enhancing the Seebeck coefficient and/or reducing the thermal conductivity. In this review, the different strategies used to optimize the thermoelectric properties of oxides and chalcogenides will be presented, starting with a review on thermoelectric oxides. The thermoelectric properties of sulfides and selenides will then be discussed, focusing on layered materials and low dimensional structures (TiS2 and pseudo-hollandites). Some sulfides with promising ZT values will also be presented (tetrahedrites and chalcopyrites).

  14. Solar thermal extraction of copper from sulfides

    Energy Technology Data Exchange (ETDEWEB)

    Winkel, L.; Guesdon, C.; Sturzenegger, M.

    2003-03-01

    With the aim to develop a solar-driven process for the extraction of copper from sulfide concentrates re-search on the decomposition of copper sulfides under inert atmospheres has been initiated. Thermogravimetric measurements on chalcocite (Cu{sub 2}S) revealed that copper is formed already at 1823 K. Chalcopyrite (CuFeS{sub 2}) also disintegrates at this temperature, although at a lower rate. Copper and iron have been identified in the solid residue. The results confirm the feasibility of copper extraction by direct decomposition of sulfides under atmospheric pressure. The decomposition under inert atmosphere prevents generation of SO{sub 2}, and is beneficial to the removal of volatile impurities. Chemical equilibrium calculations for CuFeS{sub 2} contaminated with enargite (Cu{sub 3}AsS{sub 4}) have shown that the absence of an oxidic slag allows for a complete evaporation of arsenic and subsequent separation. (author)

  15. The solubility of a metallic mineral with other coexisting minerals and the ore-forming processes of metallic sulfides

    Institute of Scientific and Technical Information of China (English)

    岑况; 於崇文

    2001-01-01

    Most metallic minerals in ore deposits are sulfides. When a sulfide mineral coexists with rock-forming minerals, its solubility is distinctly different from itself alone. The change in dissolution character of a mineral with coexisting rock-forming minerals leads to particular geochemical be-havior. The concept of solubility of a metallic mineral with coexisting rock-forming minerals and its theory and model of calculation are put forward. Taking Tianmashan Cu-Au ore deposit of sulfide minerals in Tongling district as an example, solubilities of some metallic minerals with other coex-isting minerals, such as pyrite or chalcopyrite with quartz (representing sandstone) or calcite (rep-resenting limestone), are calculated. The results show the mechanism of ore-forming processes. As the ore-forming fluid flows through sandstone, it dissolves pyrite in the sandstone at first, then transports the iron and sulfur to the interface between sandstone and limestone and eventually precipitates them on the interface.

  16. Effect of post deposition annealing on the structure, morphology, optical and electrical properties of CuInGaSe2 thin films

    Science.gov (United States)

    Pugalenthi, A. S.; Balasundaraprabhu, R.; Prasanna, S.; Habibuddin, S.; Muthukumarasamy, N.; Mohan Rao, G.; Kannan, M. D.

    2016-12-01

    Polycrystalline copper indium gallium diselenide (CIGS) thin film is a favourable candidate for solar cell applications. In the present work the effect of post-deposition annealing on the structure, surface morphology, optical and electrical properties are discussed. Initially, gallium rich CIG thin films were deposited by RF magnetron sputtering followed by an indium rich CIG layer and subjected to selenization to realize CIGS stoichiometry. X-ray diffraction (XRD) results revealed the polycrystalline nature of the films with chalcopyrite structure having preferential orientation along direction normal to the substrate. Optical properties of CIGS thin films were studied using UV-vis spectrophotometry and the band gap of CIGS was found to be around 1.15 eV. Hall Effect studies carried out on the CIGS thin films showed a linear dependence of conductivity with post deposition annealing. The elemental composition of the films was quantified using X-ray photoelectron spectroscopy (XPS) and the results are discussed.

  17. 广西某金矿工艺矿物学研究%Process Mineralogy Study of a Gold Mine in Guangxi Province

    Institute of Scientific and Technical Information of China (English)

    许霞; 苏敬韧

    2016-01-01

    The process mineralogy study of a gold mine in guangxi province shows that the gold mineral occurs mainly as native gold and is primarily hosted in pyrite, chalcopyrite, pyrrhotite and so on. Copper mineral mainly occurs in the form of chalcopryrite with few quantities of covellite. The findings of the study provide a basis for developing a reasonable metallurgical process.%对广西某矿区矿石的工艺矿物学研究表明,金以自然金为主,主要的载金矿物为黄铁矿、黄铜矿、磁黄铁矿等,铜主要以黄铜矿形式产出,有极少的铜蓝。该项研究成果为制定合理的选冶工艺提供了依据。

  18. Indium sulfide buffer/CIGSSe interface engineering: Improved cell performance by the addition of zinc sulfide

    Energy Technology Data Exchange (ETDEWEB)

    Allsop, N.A. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany)]. E-mail: allsop@hmi.de; Camus, C. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany); Haensel, A. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany); Gledhill, S.E. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany); Lauermann, I. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany); Lux-Steiner, M.C. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany); Fischer, Ch.-H. [Hahn-Meitner-Institut Berlin, Department SE2, Glienicker Str. 100, D-14109 Berlin (Germany)

    2007-05-31

    Indium sulfide buffer layers deposited by the spray-ion layer gas reaction (Spray-ILGAR) technique are a viable alternative to the traditional cadmium sulfide buffer layer in thin film solar cells. In the present work we report on the results of manipulating the absorber/buffer interface between the chalcopyrite Cu(In,Ga)(S,Se){sub 2} absorber (CIGSSe) and the indium sulfide buffer. It is shown that the deposition of a small amount of zinc sulfide at the absorber/buffer interface can be used to increase the open circuit voltage. A small but significant increase of 20 mV (up to 580 mV), as compared to the pure indium sulfide buffered cells is possible leading to an increase in the overall efficiency.

  19. Searching for new thermoelectric materials: some examples among oxides, sulfides and selenides.

    Science.gov (United States)

    Hébert, S; Berthebaud, D; Daou, R; Bréard, Y; Pelloquin, D; Guilmeau, E; Gascoin, F; Lebedev, O; Maignan, A

    2016-01-13

    Different families of thermoelectric materials have been investigated since the discovery of thermoelectric effects in the mid-19th century, materials mostly belonging to the family of degenerate semi-conductors. In the last 20 years, new thermoelectric materials have been investigated following different theoretical proposals, showing that nanostructuration, electronic correlations and complex crystallographic structures (low dimensional structures, large number of atoms per lattice, presence of 'rattlers'…) could enhance the thermoelectric properties by enhancing the Seebeck coefficient and/or reducing the thermal conductivity. In this review, the different strategies used to optimize the thermoelectric properties of oxides and chalcogenides will be presented, starting with a review on thermoelectric oxides. The thermoelectric properties of sulfides and selenides will then be discussed, focusing on layered materials and low dimensional structures (TiS2 and pseudo-hollandites). Some sulfides with promising ZT values will also be presented (tetrahedrites and chalcopyrites).

  20. Numerical simulation analysis of Guixi copper flash smelting furnace

    Institute of Scientific and Technical Information of China (English)

    2002-01-01

    A numerical simulation analysis for reactions of chalcopyrite and pyrite particles coupled with momentum, heat and mass transfer between the particle and gas in a flash smelting furnace is presented. In the simulation, the equations governing the gas flow are solved numerically by Eular method. The particle phase is introduced into the gas flow by the particle-source-in-cell technique (PSIC). Predictions including the fluid flow field, temperature field, concentration field of gas phase and the tracks of particles have been obtained by the numerical simulation. The visualized results show that the reaction of sulfide particles is almost completed in the upper zone of the shaft within 1.5 m far from the central jet distributor (CJD) type concentrate burner. The simulation results are in good agreement with data obtained from a series of experiments and tests in the plant and the error is less than 2%.

  1. Inkjet printed Cu(In,Ga)S2 nanoparticles for low-cost solar cells

    Science.gov (United States)

    Barbé, Jérémy; Eid, Jessica; Ahlswede, Erik; Spiering, Stefanie; Powalla, Michael; Agrawal, Rakesh; Del Gobbo, Silvano

    2016-12-01

    Cu(In,Ga)Se2 (CIGSe) thin film solar cells were fabricated by direct inkjet printing of Cu(In,Ga)S2 (CIGS) nanoparticles followed by rapid thermal annealing under selenium vapor. Inkjet printing is a low-cost, low-waste, and flexible patterning method which can be used for deposition of solution-based or nanoparticle-based CIGS films with high throughput. XRD and Raman spectra indicate that no secondary phase is formed in the as-deposited CIGS film since quaternary chalcopyrite nanoparticles are used as the base solution for printing. Besides, CIGSe films with various Cu/(In + Ga) ratios could be obtained by finely tuning the composition of CIGS nanoparticles contained in the ink, which was found to strongly influence the devices performance and film morphology. To date, this is the first successful fabrication of a solar device by inkjet printing of CIGS nanoparticles.

  2. Optoelectronic and low temperature thermoelectric studies on nanostructured thin films of silver gallium selenide

    Science.gov (United States)

    Jacob, Rajani; Philip, Rachel Reena; Nazer, Sheeba; Abraham, Anitha; Nair, Sinitha B.; Pradeep, B.; Urmila, K. S.; Okram, G. S.

    2014-01-01

    Polycrystalline thin films of silver gallium selenide were deposited on ultrasonically cleaned soda lime glass substrates by multi-source vacuum co-evaporation technique. The structural analysis done by X-ray diffraction ascertained the formation of nano structured tetragonal chalcopyrite thin films. The compound formation was confirmed by X-ray photo-electron spectroscopy. Atomic force microscopic technique has been used for surface morphological analysis. Direct allowed band gap ˜1.78eV with high absorption coefficient ˜106/m was estimated from absorbance spectra. Low temperature thermoelectric effects has been investigated in the temperature range 80-330K which manifested an unusual increase in Seebeck coefficient with negligible phonon drag toward the very low and room temperature regime. The electrical resistivity of these n-type films was assessed to be ˜2.6Ωm and the films showed good photo response.

  3. Utilization of polysaccharides as depressants for the flotation separation of copper/lead concentrate

    Institute of Scientific and Technical Information of China (English)

    Qin Wenqing; Wei Qian; Jiao Fen; Yang Congren; Liu Ruizeng; Wang Peipei; Ke Lifang

    2013-01-01

    The interaction mechanism between dextrin and minerals has been investigated through micro-flotation,adsorption density measurements,Fourier transform infrared ray (FTIR) spectroscopic studies and dissolution tests.Dextrin shows a good depressing action towards galena but not chaicopyrite.FTIR spectroscopic studies indicate that dextrin chemically adsorbed on galena surface in alkaline pH range.Dissolution tests confirm leaching action of metal ions from chalcopytite and galena surfaces,and dextrin-lead ion interaction.Adsorption measurements present that the higher adsorption density of O-isopropyl-N-ethyl thionocarbamate (IPETC) onto chalcopyrite than that onto galena,and IPETC adsorbed on galena decrease with increasing dextrin concentrations in the presence of dextrin,attesting the flotation results.

  4. Recent Progress Towards Space Applications Of Thin Film Solar Cells- The German Joint Project 'Flexible CIGSE Thin Film Solar Cells For Space Flight' And OOV

    Science.gov (United States)

    Brunner, Sebastian; Zajac, Kai; Nadler, Michael; Seifart, Klaus; Kaufmann, Christian A.; Caballero, Raquel; Schock, Hans-Werner; Hartmann, Lars; Otte, Karten; Rahm, Andreas; Scheit, Christian; Zachmann, Hendrick; Kessler, Friedrich; Wurz, Roland; Schulke, Peter

    2011-10-01

    A group of partners from an academic and industrial background are developing a flexible Cu(In,Ga)Se2 (CIGSe) thin film solar cell technology on a polyimide substrate that aims to be a future alternative to current rigid solar cell technologies for space applications. In particular on missions with high radiation volumes, the superior tolerance of chalcopyrite based thin film solar cell (TFSC) technologies with respect to electron and proton radiation, when compared to the established Si- or III-V based technologies, can be advantageous. Of all thin film technologies, those based on CIGSe have the highest potential to reach attractive photovoltaic conversion efficiencies and combine these with low weight in order to realize high power densities on solar cell and generator level. The use of a flexible substrate ensures a high packing density. A working demonstrator is scheduled for flight this year.

  5. Novel laser structuring of CIGSE thin film solar cells; Neuartige Laserstrukturierung von CIGSE-Duennschicht-Solarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Stegemann, B.; Schultz, C.; Schuele, M.; Richter, M.; Quaschning, V.; Fink, F. [University of Applied Sciences (HTW) Berlin (Germany); Pahl, H.U.; Endert, H. [Newport Spectra-Physics GmbH, Stahnsdorf (Germany); Bonse, J. [Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin (Germany); Rau, B.; Schlatmann, R. [PVcomB - Competence Centre Thin-Film- and Nanotechnology for Photovoltaics Berlin, Berlin (Germany)

    2011-07-01

    A major advantage of thin film photovoltaics over wafer-based photovoltaics is the monolithic series connection. Manufacturing of chalcopyrite (CICSe) thin film solar modules involves typically one laser structuring step (P1) and two mechanical structuring steps (P2 and P3) for serial interconnection. In our approach, complete laser structuring is successfully demonstrated simply by application of short nanosecond pulses (<10 ns) with a single, visible wavelength of 532 nm. The P1 and the P3 trenches are scribed by induced direct ablation. For the P2 scribe, the thermal input of the ns laser pulses is used to transform the CIGSe absorber layer locally into a highly conductive compound to provide proper electrical interconnection between the front and back contact. (orig.)

  6. Evidence for a modified-stannite crystal structure in wide band gap Cu-poor CuIn1-xGaxSe2: Impact on the optical properties

    Science.gov (United States)

    Souilah, M.; Lafond, A.; Barreau, N.; Guillot-Deudon, C.; Kessler, J.

    2008-06-01

    The crystal structure of high Ga-content CuIn1-xGaxSe2 (CIGSe) compounds has been further investigated with the help of single crystal x-ray diffraction technique. It is known that CIGSe compounds adopt the chalcopyrite crystal structure. In the case of Cu-poor, Ga-rich CIGSe, the present study shows that an alternative structure should be considered. This structure is derived from that of stannite in which there is a Ga /In segregation on two different atomic planes. The diffuse reflectance measurements of the Cu-poor compound reveal a slightly different band gap and a smoother transition compared with those of the stoichiometric compound.

  7. Effect of annealing temperature on properties of RF sputtered Cu(In,Ga)Se2 thin films

    Science.gov (United States)

    Yu, Zhou; Yan, Chuanpeng; Yan, Yong; Zhang, Yanxia; Huang, Tao; Huang, Wen; Li, Shasha; Liu, Lian; Zhang, Yong; Zhao, Yong

    2012-09-01

    Cu(In,Ga)Se2 (CIGSe) thin films were prepared by radio frequency (RF) magnetron sputtering at room temperature, following vacuum annealing at different temperatures. We have investigated the effect of annealing temperature (150-550 °C) on the phase transformation process of the CIGSe films. The as-deposited precursor films show a near stoichiometry composition and amorphous structure. Composition loss of the films mainly occur in the annealing temperature range of 150-300 °C. Comparing with samples annealed at 300 °C, films annealed at 350 °C or higher temperatures exhibit almost similar composition and polycrystalline chalcopyrite structure. Crystal quality of the films improves with increasing annealing temperature. Reflectance spectra of the annealed films show interference fringe pattern. The calculated refractive indexes of the films are in the range of 2.4-2.5.

  8. MOVPE of CuGaSe 2 on GaAs in the presence of a Cu xSe secondary phase

    Science.gov (United States)

    Gütay, Levent; Larsen, Jes K.; Guillot, Jerome; Müller, Mathias; Bertram, Frank; Christen, Jürgen; Siebentritt, Susanne

    2011-01-01

    We have grown epitaxial CuGaSe 2 layers by MOVPE on GaAs substrates. CuGaSe 2 is the highest band gap member of the chalcopyrite Cu(In,Ga)Se 2 family (CIGSe). CIGSe is used as an absorber in polycrystalline thin film solar cells. From growth experiments interrupted at different time steps we find that Ga diffusion from the substrate plays a major role in the early stages of growth. The epi-layers start to grow Ga-rich although the final film is dominated by Cu-excess and shows a homogeneous composition profile. After about 300 nm film thickness Ga diffusion becomes less dominant and the Cu-excess leads to the formation of Cu selenides on the surface. The structure of the films and intentional conversion experiments show that those crystalline Cu selenides are transformed into epitaxial CuGaSe 2 during growth.

  9. XRD and TEM characterizations of the mechanically alloyed CuIn{sub 0.5}Ga{sub 0.5}Se{sub 2} powders

    Energy Technology Data Exchange (ETDEWEB)

    Benslim, N. [Laboratoire d' Etude de Surfaces et Interfaces de la Matiere Solide (LESIMS), Departement de Physique, Faculte des Sciences, Universite Badji Mokhtar, Annaba (Algeria); Mehdaoui, S., E-mail: fac782004@yahoo.f [Laboratoire d' Etude de Surfaces et Interfaces de la Matiere Solide (LESIMS), Departement de Physique, Faculte des Sciences, Universite Badji Mokhtar, Annaba (Algeria); Aissaoui, O.; Benabdeslem, M.; Bouasla, A.; Bechiri, L. [Laboratoire d' Etude de Surfaces et Interfaces de la Matiere Solide (LESIMS), Departement de Physique, Faculte des Sciences, Universite Badji Mokhtar, Annaba (Algeria); Otmani, A. [Laboratoire de Recherche en Physico-Chimie des Surfaces et Interfaces (LRPCSI), Faculte des Sciences, Universite de Skikda, BP26 route El-Hadaek 21000, Skikda (Algeria); Portier, X. [Cimap-ENSICAEN, Universite, 6 Boulevard du Marechal Juin, 14050 Caen (France)

    2010-01-21

    The CuIn{sub 0.5}Ga{sub 0.5}Se{sub 2} (CIGS) nanocrystalline powders were prepared by mechanical alloying method. Effect of various milling times and higher milling speed on the structure of CIGS nanoparticles was investigated by X-ray diffraction measurements. The Rietveld method was used to refine the XRD data using the MAUD program. Refinement process reveals that the main phase of the CIGS powders milled for different milling times is of chalcopyrite structure. Milling time dependence of the unit-cell parameters and crystallite size has also been reported. The TEM observations demonstrated that the size of agglomerated CIGS powder is about 140 nm. The EDAX analysis of various grains of the milled powder shows that the compositions vary from one grain to another. However, the global composition was found slightly copper rich.

  10. Granite-hosted molybdenite mineralization from Archean Bundelkhand cratonmolybdenite characterization, host rock mineralogy, petrology, and fluid inclusion characteristics of Mo-bearing quartz

    Indian Academy of Sciences (India)

    J K Pati; M K Panigrahi; M Chakarborty

    2014-07-01

    The dominantly high-K, moderate to high SiO2 containing, variably fractionated, volcanic-arc granitoids (± sheared) from parts of Bundelkhand craton, northcentral India are observed to contain molybdenite (Mo) in widely separated 23 locations in the form of specks, pockets, clots and stringers along with quartz ± pyrite ± arsenopyrite ± chalcopyrite ± bornite ± covellite ± galena ± sphalerite and in invisible form as well. The molybdenite mineralization is predominantly associated with Bundelkhand Tectonic Zone, Raksa Shear Zone, and localized shear zones. The incidence of molybdenite is also observed within sheared quartz and tonalite–trondhjemite–granodiorite (TTG) gneisses. The fluid inclusion data show the presence of bi-phase (H2O–CO2), hypersaline and moderate temperature (100°–300°C) primary stretched fluid inclusions suggesting a possible hydrothermal origin for the Mo-bearing quartz occurring within variably deformed different granitoids variants of Archean Bundelkhand craton.

  11. Zn incorporation in CuInSe2: Particle size and strain effects on microstructural and electrical properties

    Indian Academy of Sciences (India)

    M Benabdeslem; A Bouasla; N Benslim; L Bechiri; S Mehdaoui; O Aissaoui; A Djekoun; M Fromm; X Portier

    2014-05-01

    Incorporation of the doping element Zn in the temperature range (550–700 °C) and the impact on structural and electrical properties of CuInSe2 material are investigated. X-ray diffraction patterns showed the chalcopyrite nature of the pure and doped CuInSe2 and revealed that diffusion temperature governs particle size as well as tensile strain. The calculated lattice parameters and cell volumes revealed that Zn diffuses in CuInSe2 by substitution on Cu sites. Electrical properties of the material have been investigated using a contact-less technique based on high frequency microwave (HF). It is found that Zn atoms influence the defect equilibrium resulting in the conversion of the conduction type. The conductivity of the samples has been found increasing as the diffusion temperature increases.

  12. Pulse-plating electrodeposition and annealing treatment of CuInSe2 films

    Institute of Scientific and Technical Information of China (English)

    LIU Fang-yang; L(U) Ying; ZHANG Zhi-an; LAI Yan-qing; LI Jie; LIU Ye-xiang

    2008-01-01

    CuInSe2 (CIS) thin film was prepared on molybdenum substrate using pulse-plating electrodeposition in aqueous solution. The most suitable pulse potential range for co-deposition is found to be from -0.55 to -0.75 V (vs SCE) from linear potential scanning curve. The electrodeposited films were characterized by X-ray diffractometry (XRD), scanning electron microscopy(SEM) and energy dispersive X-ray analysis (EDS). The annealing effects on electrodeposited precursors were investigated. And the influence of pulse parameters on film quality was studied. The chalcopyrite phase CuInSe2 films with smooth surface and stoichiometric composition are obtained at a pulse potential from -0.65 to -0.7 V (vs SCE), a pulse period of 1-9 ms with a duty cycle of 33% and annealing treatment.

  13. CuIn(S,Se){sub 2}thin film solar cells from nanocrystal inks: Effect of nanocrystal precursors

    Energy Technology Data Exchange (ETDEWEB)

    Ford, Grayson M.; Guo Qijie [School of Chemical Engineering and The Energy Center, Purdue University, 480 Stadium Mall Dr., West Lafayette, IN 47907 (United States); Agrawal, Rakesh, E-mail: agrawalr@purdue.edu [School of Chemical Engineering and The Energy Center, Purdue University, 480 Stadium Mall Dr., West Lafayette, IN 47907 (United States); Hillhouse, Hugh W., E-mail: h2@uw.edu [School of Chemical Engineering and The Energy Center, Purdue University, 480 Stadium Mall Dr., West Lafayette, IN 47907 (United States); Department of Chemical Engineering, University of Washington, Seattle WA 98105 (United States)

    2011-10-31

    CuIn(S,Se){sub 2} thin film solar cells are fabricated by selenizing CuInS{sub 2} nanocrystals synthesized using a variety of copper and indium precursors. Specifically, copper and indium acetates, acetylacetonates, iodides, chlorides and nitrates are investigated to determine the effect of precursors on electronic properties and device performance. Nanocrystal synthesis with each of these precursors can be optimized to yield similar nanocrystal composition, size and structure. In addition, dense chalcopyrite CuIn(S,Se){sub 2} thin films with micron sized grains at the surface are formed upon selenization regardless of precursor type. Surprisingly, solar cells fabricated from each nanocrystal ink have roughly the same carrier concentrations of 10{sup 16} to 10{sup 17} cm{sup -3} in the absorber layer and achieve active area efficiencies of approximately 5%.

  14. Assessment of the geoavailability of trace elements from minerals in mine wastes: analytical techniques and assessment of selected copper minerals

    Science.gov (United States)

    Driscoll, Rhonda; Hageman, Phillip L.; Benzel, William M.; Diehl, Sharon F.; Adams, David T.; Morman, Suzette; Choate, LaDonna M.

    2012-01-01

    In this study, four randomly selected copper-bearing minerals were examined—azurite, malachite, bornite, and chalcopyrite. The objectives were to examine and enumerate the crystalline and chemical properties of each of the minerals, to determine which, if any, of the Cu-bearing minerals might adversely affect systems biota, and to provide a multi-procedure reference. Laboratory work included use of computational software for quantifying crystalline and amorphous material and optical and electron imaging instruments to model and project crystalline structures. Chemical weathering, human fluid, and enzyme simulation studies were also conducted. The analyses were conducted systematically: X-ray diffraction and microanalytical studies followed by a series of chemical, bio-leaching, and toxicity experiments.

  15. Geology, Mineral Deposit Model and Potential of the Suwar Cu-Ni Sulphide Prospect, Northwest Yemen

    Institute of Scientific and Technical Information of China (English)

    Abdulkarim M.; Al-Nagashi; Li Xujun

    2002-01-01

    The Suwar Cu-Ni sulphide prospect is very highly regarded for its potential to host a major nickel-copper sulphide deposit in Republic of Yemen, a mineral resource lacking country. The ore-hosting intrusion is a lopolith about 6km long and lkm wide and more than 300m deep. There are two types of Cu-Ni mineralizations in the prospect: primary massive chalcopyrite+ pyrrhotite+ pentlandite controlled by gravitational and structural traps while the secondary Cu-Ni mineralization is coarse grained and occur as veins, veinlets, fracture fill, blebs or associated with coarse, re-crystallized carbonate in shear zones and faults. The deposit type of the prospect is believed to be the one associated with the ultramafic component of a large, broadly differentiated noritic, gabbroid intrusive. It is suggested that the prospect and adjacent area possibly contain a similar world class Ni-Cu deposits as that in Jinchuan, China.

  16. Absorption Spectra of CuGaSe 2 and CuInSe 2 Semiconducting Nanoclusters

    KAUST Repository

    Mokkath, Junais Habeeb

    2015-10-01

    The structural and optical properties of the chalcopyrite CunGanSe2n and CunInnSe2n nanoclusters (n = 2, 4, 6, and 8) are investigated as a function of the size using a combination of basin-hopping global optimization and time-dependent density functional theory. Although the lowest energy structures are found to show almost random geometries, the band gaps and absorption spectra still are subject to systematic blue shifts for decreasing cluster size in the case of CunGanSe2n, indicating strong electron confinement. The applicability of the nanoclusters in photovoltaics is discussed. © 2015 American Chemical Society.

  17. Inkjet printed Cu(In,Ga)S2 nanoparticles for low-cost solar cells

    KAUST Repository

    Barbe, Jeremy

    2016-12-13

    Cu(In,Ga)Se2 (CIGSe) thin film solar cells were fabricated by direct inkjet printing of Cu(In,Ga)S2 (CIGS) nanoparticles followed by rapid thermal annealing under selenium vapor. Inkjet printing is a low-cost, low-waste, and flexible patterning method which can be used for deposition of solution-based or nanoparticle-based CIGS films with high throughput. XRD and Raman spectra indicate that no secondary phase is formed in the as-deposited CIGS film since quaternary chalcopyrite nanoparticles are used as the base solution for printing. Besides, CIGSe films with various Cu/(In + Ga) ratios could be obtained by finely tuning the composition of CIGS nanoparticles contained in the ink, which was found to strongly influence the devices performance and film morphology. To date, this is the first successful fabrication of a solar device by inkjet printing of CIGS nanoparticles.

  18. Preparation and properties of CuInS{sub 2} thin-film by successive ionic layer adsorption and reaction (SILAR) method

    Energy Technology Data Exchange (ETDEWEB)

    Shi Yong; Jin Zhengguo; Qiu Jijun; Liu Xiaoxin [Key Lab. for Advanced Ceramics and Machining Techniques of NME, Tianjin Univ., TJ (China)

    2005-07-01

    CuInS{sub 2} thin films were deposited on glass substrate by successive ionic layer absorption and reaction (SILAR) method at room temperature. CuCl{sub 2}, InCl{sub 3}, and Na{sub 2}S were used as precursor materials. The thin films were obtained during the dipping of 20-40 cycles and after annealing in the N{sub 2} atmosphere at 500 C. The characterization of the film was carried out by X-ray diffraction, scanning electron microscopy, optical absorption spectrum and X-ray photoelectron spectra. Quantification of the XPS peaks shows that the molar ratio of Cu:In:S of the film is close to the stoichiometry of CuInS{sub 2}. XRD result demonstrated that the formed compound is CuInS{sub 2} with chalcopyrites crystal structure. Direct band gap was found to be 1.5 eV from optical absorption spectrum. (orig.)

  19. Structural controls and evolution of gold-, silver-, and REE-bearing copper-cobalt ore deposits, Blackbird district, east-central Idaho: Epigenetic origins

    Science.gov (United States)

    Lund, K.; Tysdal, R.G.; Evans, K.V.; Kunk, M.J.; Pillers, R.M.

    2011-01-01

    The Cu-Co ± Au (± Ag ± Ni ± REE) ore deposits of the Blackbird district, east-central Idaho, have previously been classified as Besshi-type VMS, sedex, and IOCG deposits within an intact stratigraphic section. New studies indicate that, across the district, mineralization was introduced into the country rocks as a series of structurally controlled vein and alteration systems. Quartz-rich and biotite-rich veins (and alteration zones) and minor albite and siderite veinlets maintain consistent order and sulfide mineral associations across the district. Both early and late quartz veins contain chalcopyrite and pyrite, whereas intermediate-stage tourmaline-biotite veins host the cobaltite. Barren early and late albite and late carbonate (generally siderite) form veins or are included in the quartz veins. REE minerals, principally monazite, allanite, and xenotime, are associated with both tourmaline-biotite and late quartz veins. The veins are in mineralized intervals along axial planar cleavage, intrafolial foliation, and shears.

  20. Ab initio calculation of ZnSiAs{sub 2} and CdSiAs{sub 2} semiconductor compounds

    Energy Technology Data Exchange (ETDEWEB)

    Boukabrine, F., E-mail: bk_fouzia@yahoo.f [Applied Materials Laboratory, Electronics Department, Djillali Liabes University of Sidi Bel-Abbes (Algeria); Physics Department, Djillali Liabes University Of Sidi Bel-Abbes (Algeria); Chiker, F. [Physics Department, Djillali Liabes University Of Sidi Bel-Abbes (Algeria); Khachai, H., E-mail: h_khachai@yahoo.f [Applied Materials Laboratory, Electronics Department, Djillali Liabes University of Sidi Bel-Abbes (Algeria); Physics Department, Djillali Liabes University Of Sidi Bel-Abbes (Algeria); Haddou, A. [Applied Materials Laboratory, Electronics Department, Djillali Liabes University of Sidi Bel-Abbes (Algeria); Physics Department, Djillali Liabes University Of Sidi Bel-Abbes (Algeria); Baki, N. [Physics Department, Djillali Liabes University Of Sidi Bel-Abbes (Algeria); Khenata, R. [Department of Physics and Astronomy, College of Science, King Saud University, P.O Box 2455, Riyadh 11451 (Saudi Arabia); Laboratoire de Physique Quantique et de Modelisation Mathematique (LPQ3M), Departement de Technologie, Universite de Mascara, 29000 (Algeria); Abbar, B. [Laboratoire de Modelisation et de Simulation en Sciences des Materiaux, Physics Department, Djillali Liabes University of Sidi Bel-Abbes (Algeria); Khalfi, A [Laboratory of Catalysis and Reactive Systems, Djillali Liabes University of Sidi Bel-Abbes (Algeria)

    2011-01-15

    In order to get a good overall description of the structural, electronic and optical properties of ternary chalcopyrite semiconductors especially for ZnSiAs{sub 2} and CdSiAs{sub 2}, they have been calculated self consistently using the full potential augmented plane wave plus local orbital method (FPAPW+lo). The calculations are presented within the local density approximation (LDA), where we clarify the electronic and optical properties for both compounds. Since, we prove the existence of the direct band gap and also the efficiency of the method to give more details about the optical properties. We found that the most important features of the band gap is pseudo-direct for ZnSiAs{sub 2}, and direct for CdSiAs{sub 2}; then the contribution of the different transitions peaks are analyzed from the imaginary part of the dielectric function and the reflectivity spectra.

  1. Composition and structure of CuInSe2 thin films prepared by vacuum evaporation of the constituent elements

    Science.gov (United States)

    Dhere, N. G.; Lourenco, M. C.; Dhere, R. G.; Kazmerski, L. L.

    1984-11-01

    The characteristics of CuInSe2 thin film solar cells produced by a three-source deposition method were investigated. The films were deposited at 350 C, followed by 30 min annealing at the same temperature. The compositions of the cells and intracell fractional variations were dependent on the proximity to the film source during formation. A chalcopyrite CuInSe2 structure was observed in X-ray diffraction patterns and high energy electron diffraction studies of the films on NaCl single crystal substrates. Grain sizes ranged from 0.2-0.6 micron, and the films had a band gap in the 1.02-1.04 eV interval.

  2. Crystallochemical and structural evolution of tourmaline in auriferous quartz veins of the Iskel terrane prospect (western Hoggar, Tamanrasset, South Algeria)

    Science.gov (United States)

    Talbi, Mohamed; Chaouche, Ismahane; Fuchs, Yves

    2016-04-01

    A mylonite zone limits the Iskane Terrane tectonic unit (Western Hoggar). This zone is intruded by granitic units belonging to the Taourirt cycle. North -South and North East-South West trending auriferous quartz veins are hosted in the cataclased areas. Visible gold can be observed but gold is also present in sulfides (pyrite, chalcopyrite). Tourmaline is abundant in these veins. Mossbauer spectrometry as well as FTIR spectrometry shows that in some sectors tourmaline underwent an oxidation process posterior to its formation. The general structure of tourmaline studied, shows the coexistence of ferric iron Fe3+ with ferrous iron Fe2+ in the Y site. This represents a tourmaline "deprotonated". This oxidation induced a partial transformation of Fe2+ in Fe3+ that is charge compensated by a deshydroxylation of the central OH group. The relationship of the gold deposition with the oxidation of tourmaline is discussed. Key words: Tourmaline, oxidation, "deprotonation-deshydroxylation", sulfides, gold.

  3. First-principles calculations of magnetic properties for CdCrO{sub 2} under pressure

    Energy Technology Data Exchange (ETDEWEB)

    Amari, S., E-mail: siham_amari@yahoo.fr [Laboratoire de Modelisation et de Simulation en Sciences des Materiaux, Departement de Physique Universite Djillali Liabes, Faculte des sciences, Universite Djillali Liabes, BP 89 Sidi Bel Abbes 22000 (Algeria); Mecabih, S.; Abbar, B.; Bouhafs, B. [Laboratoire de Modelisation et de Simulation en Sciences des Materiaux, Departement de Physique Universite Djillali Liabes, Faculte des sciences, Universite Djillali Liabes, BP 89 Sidi Bel Abbes 22000 (Algeria)

    2013-02-15

    By employing the first-principles method of the full potential linear augmented plane waves plus the local orbitals (FP-L/APW+lo) within the generalized gradient approximation for the exchange and correlation potential, the structural, electronic, and magnetic properties of chalcopyrite compound CdCrO{sub 2} are investigated. In order to take into account the strong on-site Coulomb interaction, we also performed the generalized gradient approximation plus the Hubbard correlation terms. We systematically study how the exchange interactions and magnetic moments of CdCrO{sub 2} are affected by the different choice of U as well as the exchange correlation potential. We have also carried out the pressure effect on the magnetic properties. - Highlights: Black-Right-Pointing-Pointer The calculation of the exchange constants. Black-Right-Pointing-Pointer The pressure dependence of the magnetic properties. Black-Right-Pointing-Pointer The exchange correlation potential effect on the magnetic properties.

  4. New data on the age of gold mineralization of the Lugokan ore cluster (Eastern Transbaikalia)

    Science.gov (United States)

    Redin, Yu. O.; Dultsev, V. F.; Nevolko, P. A.; Ponomarchuk, A. V.

    2016-08-01

    The Lugokan ore cluster is located in the southeastern part of Transbaikalia within the Aga-Borzya structural-formational zone of the Mongol-Okhotsk orogenic belt. The 40Ar/39Ar dating of K-bearing minerals of syngenetic to ore parageneses has been carried out applying stepwise heating technique: it has been demonstrated that the earliest gold-ore mineral associations are Au-pyrite-arsenopyrite (163 ±1.9 Ma) and Au-chalcopyrite (160 ±2 Ma). The later parageneses encompass the Au-polymetallic (156.3 ± 1.8 Ma) and Au-Bi (155.9 ± 4.5 Ma) one. By their ages and position in the general scheme of the Late Jurassic magmatism of Eastern Transbaikalia, the Lugokan's ore cluster gold-bearing mineral associations corresponds to the time of intrusion of the Shakhtama pluton (161 Ma) and the Porphyry Complex (159-155 Ma).

  5. Temperature variation of the fundamental absorption edge in AgGaSe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Calderon, E., E-mail: saernest@ula.v [Centro de Estudios de Semiconductores, Facultad de Ciencias, Universidad de los Andes, Merida 5101 (Venezuela, Bolivarian Republic of); Fernandez, B.; Duran, L.; Grima, P.; Morocoima, M.; Quintero, E.; Rincon, C.; Quintero, M. [Centro de Estudios de Semiconductores, Facultad de Ciencias, Universidad de los Andes, Merida 5101 (Venezuela, Bolivarian Republic of)

    2009-11-15

    Optical absorption measurements were made in the temperature range 9-300 K on the chalcopyrite semiconductor compound AgGaSe{sub 2} and the optical energy gap E{sub G} determined as a function of temperature T. In order to obtain the values of E{sub G} as a function of T, the Elliot-Toyozawa model [R.J. Elliot, J. Phys. Rev. 108 (1957) 1384; D.D. Sell, P. Lawaets, Phys. Rev. Lett. 26 (1971) 311] was employed to perform the analysis of the optical absorption spectra. The resulting E{sub G} vs. T curve was fitted to a semi-empirical model that takes into account both the thermal expansion and the electron-phonon interaction contributions. The results have been used to estimate values of the deformation potentials of the valence and conduction bands of the compound.

  6. Drilling successful from ROV Ventana

    Science.gov (United States)

    Stakes, Debra S.; McFarlane, James A. R.; Holloway, G. Leon; Greene, H. Gary

    Cores of granite and deformed sediment from the walls of Monterey Canyon were successfully recovered from December 30 to 31, 1992, by Monterey Bay Aquarium Research Institute's (MBARI) Remotely Operated Vehicle (ROV) Ventana using a small-diameter, double-barrel drill with a diamond bit. This HSTR (Holloway-Stakes-Tengdin-Rajcula) drill was developed to drill cores horizontally from sulfide/sulfate walls of active black smokers. The drill was first successfully used by the submersible Alvin in October 1991 to drill into massive sulfide chimneys, on the Juan de Fuca Ridge (Eos, June 30, 1992, p. 273), and it was subsequently used with equal success on the chalcopyrite-rich chimneys from 21°N and 9°N on the East Pacific Rise. The recent December dives, however, marked the first time that drilling has ever been attempted from the smaller ROV and the first time coring into the harder igneous rock substrate has been attempted.

  7. Rule of oxygen transmission in dump leaching

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    According to the chemical equations, the flux and concentration of oxygen required during bacterial leaching sulfuric mineral were investigated; the rule of air bubble transmitted in granular was researched in the Dump Leaching Plant of Dexing Copper Mine. The results show that lack of oxygen in dump leaching is the critical factor of restricting leaching reaction. Pyrite is the primary oxygen-consuming mineral in bioleaching. When its content is too high, it needs a great deal of oxygen for reaction and competes for the finite oxygen with objective minerals, and thus the leaching velocity decreases greatly. The average size of ore particles and diameter of bubbles are the key parameters affecting the mass transfer coefficient. Reverse analysis was adopted, and it shows that 44.8 m3 air per unit ore can meet the requirement of production if the molar ratio of pyrite to chalcopyrite is 10.

  8. Combined Raman-DLTS investigations of n-type Cu-In-S absorber layers grown on Cu tape substrate (CISCuT)

    Energy Technology Data Exchange (ETDEWEB)

    Trushin, M.; Klossek, A. [Joint Lab IHP/BTU, Konrad-Wachsmann-Allee 1, 03046 Cottbus (Germany); Arguirov, T.; Kittler, M.; Seifert, W. [Joint Lab IHP/BTU, Konrad-Wachsmann-Allee 1, 03046 Cottbus (Germany); IHP, Im Technologiepark 25, 15236 Frankfurt (Oder) (Germany); Bernhard, T.; Gerlach-Blumenthal, W.; Haensel, A.; Tober, O.; Schwabe, M. [Odersun AG, Im Technologiepark 6, 15236 Frankfurt (Oder) (Germany)

    2013-01-15

    Thin absorber films grown by the CuInS{sub 2}-on-Cu-tape (CISCuT) method were studied by Raman spectroscopy and deep-level transient spectroscopy (DLTS). Raman measurements revealed a degradation of crystalline quality and a growth of the CuAu fraction with the increase of Cu-tape velocity through the sulfur chamber, whereas DLTS method - corresponding variations in the magnitude of the dominating peak E1. The origin of the E1 peak was established from the correlation of Raman and DLTS results and ascribed to defect states at the interface between chalcopyrite and CuAu phase. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  9. Representations of the occupation number matrix on the LDA/GGA+U method

    Energy Technology Data Exchange (ETDEWEB)

    Tablero, C [Instituto de EnergIa Solar, Universidad Politecnica de Madrid, Ciudad Universitaria s/n, E-28040 Madrid (Spain)

    2008-08-13

    An analysis of the general representation of the occupation number matrix on density functional theory in conjunction with the generalized Hubbard model is presented. A central fact that will be addressed is that the total charge density cannot be broken down into simple atomic contributions. This fact means that the orbital occupations are not well defined. Different representations of the occupation number matrix, both that it conserves and that it does not conserve the number of electrons of the system, are compared. A localized basis set is used, which is suitable for large-scale electronic structure calculations based on the density functional theory. This methodology is applied to typical and well-analysed transition-metal oxide bulk systems and to Cr-doped zinc chalogenides and chalcopyrites. The bandgap, magnetic moment and detailed electronic structures are investigated and discussed with the different choices of the occupation number matrix. The results are in good agreement with previous theoretical and experimental studies.

  10. Electrodeposition and Characterization of CulnSe2 Thin Films for Solar Cells

    Institute of Scientific and Technical Information of China (English)

    LI Jianzhuang; ZHAO Xiujian; XIA Donglin

    2007-01-01

    CuInSe2 (CIS) thin films were prepared by electrodeposition from the de-ionized water solution consisting of CuCl2, InCl3, H2SeO3 and Na-citrate onto Mo/soda-lime glass (SLG) substrates. A thermal processing in Se atmosphere at 450 ℃ was carried out for the electrodepositied films to improve the stoichiometry. The composition and morphology of selenized CIS thin films were studied using energy dispersive spectroscopy (EDS) and scanning electron microscopy (SEM), respectively. X-ray diffraction(XRD) studies show that the annealing in Se atmosphere at 450 ℃ promotes the structural formation of CIS chalcopyrite structure.

  11. Progress report - Physical and Environmental Sciences - Physics Division, 1996 January 1 to December 31

    Energy Technology Data Exchange (ETDEWEB)

    Powell, B.M. (ed.)

    1997-04-01

    This document is the last Progress Report for the Neutron and Condensed Matter Science Branch, at Chalk River Labs of Atomic Energy of Canada Limited. The materials science program continued to include measurements of stress as a major component, but the determination of phase diagrams for specific alloys was also a prominent activity. Studies were made of two types of unusual magnetic materials. The magnetic properties of several oxide pyrochlore were investigated and spin waves were measured in the magnetic semiconductor, chalcopyrite. The crystal structures of the deuterated anti fluorite were determined and the reorientation of the ammonium ion was refined in detail. Differential scanning calorimetry measurements were used to investigate whether spontaneous phase separation into chiral domains occurs for mixtures of DPPC of opposite chirality. A new Neutron Velocity Selector was commissioned.

  12. Attosecond nanotechnology: Quantum dots of nanoelectromechanical systems of CuInxGa1-xSe2 compounds

    Science.gov (United States)

    Beznosyuk, Sergey A.; Terentyeva, Yulia V.; Maslova, Olga A.; Zhukovsky, Mark S.; Volkov, Dmitrii A.

    2016-11-01

    In this paper the problem of stability of Cu(In,Ga)Se2 (CIGS) compounds as the continuous solid solution composition CuInxGa1-xSe2 with the structure of chalcopyrite in the state of quantum dots of nanoelectromechanical systems (NEMS) is studied. Variations of energy, geometry, and paired radial distribution functions of atoms of stable NEMS quantum dots of CIGS at the three temperatures 0, 77, and 293 K are investigated. It is revealed that the relative change in parameters of sustainable CIGS nanolayers in the state of NEMS quantum dots is nonlinearly dependent on the concentration of indium atoms in the system. We show that this behavior is a result of the significant difference of energy and lengths of In-Se and Ga-Se bonds of NEMSs in the first coordination sphere of selenium atoms.

  13. Ore Mineralogy Features of Hayriye and Arapdede Mineralizations in (Inegol-Bursa) Area

    Science.gov (United States)

    Sendir, Hüseyin; Kocatürk, Hüseyin; Cesur, Duru; Toygar, Özlem

    2016-04-01

    Western Anatolia (Turkey) experienced widespread Cenozoic magmatism after the collision between the Sakarya and Anatolide-Tauride continental blocks in the pre-middle Eocene. The widespread magmatic activity in NW Anatolia postdates this continental collisional event in the region. The following magmatic episode during the Oligocene and Early Miocene is known to have produced the widespread granitic plutons. Many skarn mineralization associated with plutons formed in the region (such as Hayriye and Arapdede Mineralizations). The Paleozoic aged Devlez Metabasite is the oldest unit of the study area. This unit includes amphibolite, glaucophane-lawsonite schist, muscovite schists. The unit has widely spread in area. This units are overlain unconformably by the Geyiktepe Marbles. Paleocene aged Domaniç granitoidic intrusives cut other rock series and located as a batholite. Magmatic units present porphyric and holocrystalline textures. Granitoidic intrusions are represented by tonalite, tonalite porphyr, granodiorite, granodiorite porphyr, granite, diorite, diorite porphyries. The Domaniç granitoid intruded in to the metamorphides during Paleocene and caused formations of skarn zones and related Cu-Pb-Zn mineralizations along the contacts. Mineralizations are known in the locations named as Arapdede and Hayriye. The mineralizations occur along the metamorphites - plutonics contact, in the pockets and fractures extending towards marble. The thickness of the mineralized bodies can reach up to 1 -2 m. Primary minerals are galenite, magnetite, pyrite, chalcopyrite and sphalerite at Hayriye mineralizations and sphalerite, galenite, chalcopyrite and pyrite minerals at the Arapdede mineralizations. This study supported by ESOGU BAP (201115031) Keywords: Ore mineralogy, mineralization, Cu-Pb-Zn deposits, Inegöl (Bursa).

  14. Age constraints on the hydrothermal history of the Prominent Hill iron oxide copper-gold deposit, South Australia

    Science.gov (United States)

    Bowden, Bryan; Fraser, Geoff; Davidson, Garry J.; Meffre, Sebastien; Skirrow, Roger; Bull, Stuart; Thompson, Jay

    2016-12-01

    The Mesoproterozoic Prominent Hill iron-oxide copper-gold deposit lies on the fault-bound southern edge of the Mt Woods Domain, Gawler Craton, South Australia. Chalcocite-bornite-chalcopyrite ores occur in a hematitic breccia complex that has similarities to the Olympic Dam deposit, but were emplaced in a shallow water clastic-carbonate package overlying a thick andesite-dacite pile. The sequence has been overturned against the major, steep, east-west, Hangingwall Fault, beyond which lies the clastic to potentially evaporitic Blue Duck Metasediments. Immediately north of the deposit, these metasediments have been intruded by dacite porphyry and granitoid and metasomatised to form magnetite-calc-silicate skarn ± pyrite-chalcopyrite. The hematitic breccia complex is strongly sericitised and silicified, has a large sericite ± chlorite halo, and was intruded by dykes during and after sericitisation. This paper evaluates the age of sericite formation in the mineralised breccias and provides constraints on the timing of granitoid intrusion and skarn formation in the terrain adjoining the mineralisation. The breccia complex contains fragments of granitoid and porphyry that are found here to be part of the Gawler Range Volcanics/Hiltaba Suite magmatic event at 1600-1570 Ma. This indicates that some breccia formation post-dated granitoid intrusion. Monazite and apatite in Fe-P-REE-albite metasomatised granitoid, paragenetically linked with magnetite skarn formation north of the Hangingwall Fault, grew soon after granitoid intrusion, although the apatite experienced U-Pb-LREE loss during later fluid-mineral interaction; this accounts for its calculated age of 1544 ± 39 Ma. To the south of the fault, within the breccia, 40Ar-39Ar ages yield a minimum age of sericitisation (+Cu+Fe+REE) of dykes and volcanics of ˜1575 Ma, firmly placing Prominent Hill ore formation as part of the Gawler Range Volcanics/Hiltaba Suite magmatic event within the Olympic Cu-Au province of the

  15. Trace Metal and Sulfur Dynamics in the First Meter of Buoyant Hydrothermal Vent Plumes

    Science.gov (United States)

    Findlay, A.; Gartman, A.; Shaw, T. J.; Luther, G. W., III

    2014-12-01

    The speciation and reactivity of metals and metal sulfides within the buoyant plume is critical to determining the ultimate fate of metals emitted from hydrothermal vents. The concentration, size fractionation, and partitioning of trace metals (Fe, Mn, Cu, Co, Zn, Cd, Pb) were determined within the first meter of the rising plume at three vent fields (TAG, Snakepit, and Rainbow) along the Mid-Atlantic Ridge. At Rainbow, total Fe concentrations exceed total sulfide concentrations by an order of magnitude, whereas at the other two sites, total Fe and total sulfide concentrations are nearly equal. At all three sites, Mn and Fe are primarily in the filtered (< 0.2 μm) fraction and Cu, Co, Zn, Cd, and Pb are mainly in the unfiltered fraction. At TAG and Snakepit, unfiltered copper is correlated with unfiltered cobalt, and unfiltered zinc is correlated with unfiltered cadmium and lead. At Rainbow, unfiltered zinc, cadmium and lead are correlated, but unfiltered copper and cobalt are not, indicating precipitation dynamics at Rainbow are different than those at TAG and Snakepit due to bulk geochemical differences, including a higher iron to sulfide ratio. A sequential HCl/HNO3 leaching method was used to distinguish metals present in pyrite and chalcopyrite in both unfiltered and filtered samples. Significant portions of unfiltered Cu and Co were extracted in HNO3, whereas unfiltered Zn, Cd, and Pb were extracted in HCl. Up to 95 % of filtered Cu, Co, and Zn, up to 80% Cd, and up to 60 % Pb are only extractable in HNO3, indicating that a significant portion of metals < 0.2 μm are incorporated into a recalcitrant fraction such as nanoparticulate pyrite or chalcopyrite.

  16. Sulfide oxidation as a process for the formation of copper-rich magmatic sulfides

    Science.gov (United States)

    Wohlgemuth-Ueberwasser, Cora C.; Fonseca, Raúl O. C.; Ballhaus, Chris; Berndt, Jasper

    2013-01-01

    Typical magmatic sulfides are dominated by pyrrhotite and pentlandite with minor chalcopyrite, and the bulk atomic Cu/Fe ratio of these sulfides is typically less than unity. However, there are rare magmatic sulfide occurrences that are dominated by Cu-rich sulfides (e.g., bornite, digenite, and chalcopyrite, sometimes coexisting with metallic Cu) with atomic Cu/Fe as high as 5. Typically, these types of sulfide assemblages occur in the upper parts of moderately to highly fractionated layered mafic-ultramafic intrusions, a well-known example being the Pd/Au reef in the Upper Middle Zone of the Skaergaard intrusion. Processes proposed to explain why these sulfides are so unusually rich in Cu include fractional crystallization of Fe/(Ni) monosulfide and infiltration of postmagmatic Cu-rich fluids. In this contribution, we explore and experimentally evaluate a third possibility: that Cu-rich magmatic sulfides may be the result of magmatic oxidation. FeS-dominated Ni/Cu-bearing sulfides were equilibrated at variable oxygen fugacities in both open and closed system. Our results show that the Cu/Fe ratio of the sulfide melt increases as a function of oxygen fugacity due to the preferential conversion of FeS into FeO and FeO1.5, and the resistance of Cu2S to being converted into an oxide component even at oxygen fugacities characteristic of the sulfide/sulfate transition (above FMQ + 1). This phenomenon will lead to an increase in the metal/S ratio of a sulfide liquid and will also depress its liquidus temperature. As such, any modeling of the sulfide liquid line of descent in magmatic sulfide complexes needs to address this issue.

  17. Platinum-group mineralization at the margin of the Skaergaard intrusion, East Greenland

    Science.gov (United States)

    Andersen, Jens C. Ø.; Rollinson, Gavyn K.; McDonald, Iain; Tegner, Christian; Lesher, Charles E.

    2017-01-01

    Two occurrences of platinum-group elements (PGEs) along the northern margin of the Skaergaard intrusion include a sulfide-bearing gabbro with slightly less than 1 ppm PGE + Au and a clinopyroxene-actinolite-plagioclase-biotite-ilmenite schist with 16 vol% sulfide and 1.8 ppm PGE + Au. Both have assemblages of pyrrhotite, pentlandite, and chalcopyrite typical for orthomagmatic sulfides. Matching platinum-group mineral assemblages with sperrylite (PtAs2), kotulskite (Pd(Bi,Te)1-2), froodite (PdBi2), michenerite (PdBiTe), and electrum (Au,Ag) suggest a common origin. Petrological and geochemical similarities suggest that the occurrences are related to the Skaergaard intrusion. The Marginal Border Series locally displays Ni depletion consistent with sulfide fractionation, and the PGE fractionation trends of the occurrences are systematically enriched by 10-50 times over the chilled margin. The PGE can be explained by sulfide-silicate immiscibility in the Skaergaard magma with R factors of 110-220. Nickel depletion in olivine suggests that the process occurred within the host cumulate, and the low R factors require little sulfide mobility. The sulfide assemblages are different to the chalcopyrite-bornite-digenite assemblage found in the Skaergaard Layered Series and Platinova Reef. These differences can be explained by the early formation of sulfide melt, while magmatic differentiation or sulfur loss caused the unusual sulfide assemblage within the Layered Series. The PGEs indicate that the sulfides formed from the Skaergaard magma. The sulfides and PGEs could not have formed from the nearby Watkins Fjord wehrlite intrusion, which is nearly barren in sulfide. We suggest that silicate-sulfide immiscibility led to PGE concentration where the Skaergaard magma became contaminated with material from the Archean basement.

  18. Genesis of Pb-Zn-Cu-Ag Deposits within Permian Carboniferous-Carbonate Rocks in Madina Regency, North Sumatra

    Directory of Open Access Journals (Sweden)

    Bhakti Hamonangan Harahap

    2015-11-01

    Full Text Available Strong mineralized carbonate rock-bearing Pb-Zn-Cu-Ag-(Au ores are well exposed on the Latong River area, Madina Regency, North Sumatra Province. The ore deposit is hosted within the carbonate rocks of the Permian to Carboniferous Tapanuli Group. It is mainly accumulated in hollows replacing limestone in the forms of lensoidal, colloform, veins, veinlets, cavity filling, breccia, and dissemination. The ores dominantly consist of galena (126 000 ppm Pb and sphalerite (2347 ppm Zn. The other minerals are silver, azurite, covellite, pyrite, marcasite, and chalcopyrite. This deposit was formed by at least three phases of mineralization, i.e. pyrite and then galena replaced pyrite, sphalerite replaced galena, and pyrite. The last phase is the deposition of chalcopyrite that replaced sphalerite. The Latong sulfide ore deposits posses Pb isotope ratio of 206Pb/204Pb = 19.16 - 20.72, 207Pb/204Pb = 16.16 - 17.29, and 208Pb/204Pb = 42.92 - 40.78. The characteristic feature of the deposit indicates that it is formed by a sedimentary process rather than an igneous activity in origin. This leads to an interpretation that the Latong deposit belongs to the Sedimentary Hosted Massive Sulfide (SHMS of Mississippi Valley-Type (MVT. The presence of SHMS in the island arc such as Sumatra has become controversial. For a long time, ore deposits in the Indonesian Island Arc are always identical with the porphyry and hydrothermal processes related to arc magmatism. This paper is dealing with the geology of Latong and its base metal deposits. This work is also to interpret their genesis as well as general relationship to the regional geology and tectonic setting of Sumatra.

  19. Discussion for Grinding Technique of a Copper-molybdenum Mine in Jilin Province%吉林某铜钼矿磨矿工艺探讨

    Institute of Scientific and Technical Information of China (English)

    金明水; 王大明

    2013-01-01

    吉林某铜钼矿具有回收价值的为辉钼矿和黄铜矿,浸染粒度以粗、细粒为主,不均匀嵌布。辉钼矿和黄铜矿除与脉石矿物嵌布关系紧密外,与其他金属矿物很少有嵌布关系,矿石结构构造较为简单。磨矿分级产品质量直接影响选别指标,合理确定磨矿细度,对简化磨矿流程、节省投资、降低能耗,提高选厂经济效益有着重要意义。%The ore which is based on recovery value is the molybdenite and the chalcopyrite that is from a copper-molybdenum mine in Jilin . The disseminated grain size of the ore is mainly to be coarse and fine , the grain is inbuilt unevenly . The disseminated relationship of molybdenite and chalcopyrite to the metallic is not close besides the gangue , the texture and structure of the ore is simpler . The production quality of the ore which is from the grinding and classification flowsheet will influence the index directly , so it is im-portant to define the mog reasonably for simplifying grinding flowsheet , reducing investment outlay and energy consumption , and enhancing economic performance of the concentration plant .

  20. Influencia de la temperatura en la fijación y penetración de la plata durante la lixiviación de calcopirita con microorganismos termófilos moderados

    Directory of Open Access Journals (Sweden)

    Cancho, L.

    2004-06-01

    Full Text Available Bioleaching of chalcopyrite using mesophilic microorganisms considerably improves in the presence of silver. However, the studies carried out with moderate thermophilic microorganisms do not show a significant improvement with regard to the use of mesophilic bacteria. The main objective of the present work has been to study the silver fixation on chalcopyrite at 35 and 45 °C and its influence on the microbiological attack. Different observations using SEM, EDS microanalysis and concentration profiles using electron microprobe have been carried out. The study of the different samples showed that silver fixation was more favourable at 35 °C than at 45 °C. In addition, bacterial action improved silver penetration through attack cracks.

    La biolixiviación de la calcopirita con microorganismos mesófilos mejora considerablemente cuando se utiliza plata en el medio de reacción. Sin embargo, los estudios realizados con microorganismos termófilos moderados no muestran una mejora significativa con respecto a la utilización de bacterias mesófilas. El objetivo del presente trabajo ha sido el estudio de la fijación de plata sobre calcopirita a 35 y 45 °C y su influencia en el ataque microbiológico. Se han realizado observaciones con SEM, microanálisis por EDS y perfiles de concentración con microsonda electrónica. El estudio de las distintas muestras reveló que la fijación de la plata fue más favorable a 35 que a 45 °C y que la acción bacteriana favoreció la penetración de la plata a través de las grietas de ataque.

  1. The influence of stoichiometry and annealing temperature on the properties of CuIn{sub 0.7}Ga{sub 0.3}Se{sub 2} and CuIn{sub 0.7}Ga{sub 0.3}Te{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Fiat, S. [GaziosmanpaşaUniversity, Faculty of Arts and Sciences, Physics Department, 60240 Tokat (Turkey); Koralli, P. [School of Mechanical Engineering, National Technical University of Athens, 9, Iroon Polytechniou, Zografos, 15780 Athens (Greece); Bacaksiz, E. [Karadeniz Technical University, Faculty of Arts and Sciences, Physics Department, 61080 Trabzon (Turkey); Giannakopoulos, K.P. [N.C.S.R. “Demokritos,” Institute for Advanced Materials, Physicochemical Processes, Nanotechnology and Microsystems, 15310 Aghia Paraskevi, Athens (Greece); Kompitsas, M., E-mail: mcomp@eie.gr [National Hellenic Research Foundation, Theoretical and Physical Chemistry Institute, 11635 Athens (Greece); Manolakos, D.E. [School of Mechanical Engineering, National Technical University of Athens, 9, Iroon Polytechniou, Zografos, 15780 Athens (Greece); Çankaya, G. [Yıldırım Beyazıt University, Faculty of Engineering and Natural Sciences, Materials Engineering, 06030 Ankara (Turkey)

    2013-10-31

    CuIn{sub 0.7}Ga{sub 0.3}Se{sub 2} and CuIn{sub 0.7}Ga{sub 0.3}Te{sub 2} thin films have been prepared by the electron beam evaporation technique and annealed at various temperatures (450 °C, 475 °C, 500 °C, 525 °C and 600 °C). Optical transmittance measurements have been carried out in the wavelength range 300–1200 nm. The films show high absorption in the solar radiation spectral range, and their optical band gaps range from 1.33 eV to 1.22 eV for CuIn{sub 0.7}Ga{sub 0.3}Se{sub 2} and from 1.13 eV to 1.06 eV for CuIn{sub 0.7}Ga{sub 0.3}Te{sub 2}, depending on the annealing temperature. X-ray diffraction (XRD) indicates the films are crystallized in a single phase with the chalcopyrite structure and a preferred orientation along the (112) plane. The dependence of the lattice parameters on the composition of the films is investigated. Surface morphology has been determined by atomic force microscopy (AFM) and scanning electron microscopy (SEM). These results are correlated with the XRD microstructural analysis. - Highlights: • Chalcopyrite CIGSe and CIGTe thin films have been grown by e-beam evaporation. • The samples have been annealed at 4 different temperatures up to 600 °C. • Annealing effects on the optical properties, morphology and structure were analyzed. • Annealing improves crystallinity and increases grain size. • Energy band gap reduces with annealing temperature and Se replacement by Te.

  2. Structural investigation of the Cu 2Se-In 2Se 3-Ga 2Se 3 phase diagram, X-ray photoemission and optical properties of the Cu 1- z(In 0.5Ga 0.5) 1+ z/3 Se 2 compounds

    Science.gov (United States)

    Souilah, M.; Lafond, A.; Guillot-Deudon, C.; Harel, S.; Evain, M.

    2010-10-01

    Structures of compounds in the Cu 2Se-In 2Se 3-Ga 2Se 3 system have been investigated through X-ray diffraction. Single crystal structure studies for the so-called stoichiometric compounds Cu(In,Ga)Se 2 (CIGSe) confirm that the chalcopyrite structure (space group I4¯2 d) is very flexible and can adapt itself to the substitution of Ga for In. On the other hand a structure modification is evidenced in the Cu 1- z(In 0.5Ga 0.5) 1+ z/3 Se 2 series when the copper vacancy ratio ( z) increases; the chalcopyrite structure turns to a modified-stannite structure ( I4¯2 m) when z≥0.26. There is a continuous evolution of the structure from Cu 0.74(In 0.5Ga 0.5) 1.09Se 2 to Cu 0.25(In 0.5Ga 0.5) 1.25Se 2 ((i.e. Cu(In 0.5Ga 0.5) 5Se 8), including Cu 0.4(In 0.5Ga 0.5) 1.2Se 2 (i.e. Cu(In 0.5Ga 0.5) 3Se 5). From this single crystal structural investigation, it is definitively clear that no ordered vacancy compound exists in that series. X-ray photoemission spectroscopy study shows for the first time that the surface of powdered Cu 1- z(In 0.5Ga 0.5) 1+ z/3 Se 2 compounds ( z≠0) is more copper-poor than the bulk. The same result has often been observed on CIGSe thin films material for photovoltaic applications. In addition, optical band gaps of these non-stoichiometric compounds increase from 1.2 to 1.4 eV when z varies from 0 to 0.75.

  3. Synthesis of Culn(1-x)Ga(x)Se2 Nanoparticles by Thermal Decomposition Method with Tunable Ga Content.

    Science.gov (United States)

    Latha, M; Devi, R Aruna; Velumani, S; Oza, Goldie; Reyes-Figueroa, P; Rohini, M; Becerril-Juarez, I G; Yi, Junsin

    2015-11-01

    Chalcopyrite Culn(1-x)Ga(x)Se2 (CIGS) nanoparticles were synthesized by mixing copper (I) chloride (CuCl), Indium (III) chloride (InCl3), gallium (III) chloride (GaCl3) and selenium (Se) in oleylamine (OLA) at 260 degrees C for 4 h under nitrogen atmosphere. The Ga/(In+ Ga) ratio was tuned across the entire stoichiometric range from 0 to 1. X-ray diffraction analysis (XRD) revealed chalcopyrite crystal structure for samples prepared with x = 0, 0.3, 0.5, 0.7 and 1. The lattice parameters a and c decreased linearly with increasing Ga concentration which is consistent with Vegard's law. Raman spectra exhibited A, optical phonon vibrational mode for synthesized nanoparticles which gradually shifted to higher wavenumber with increasing Ga content. Field emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM) images showed irregular as well as hexagonal plate like morphologies in the size range of 100 to 400 nm. High-resolution transmission electron microscopy (HR-TEM) images showed well-defined lattice fringes and d-spacing correspond to (112) plane which gradually decreases with increasing Ga content. The material compositions of synthesized CIGS nanoparticles with x = 0, 0.3, 0.5, 0.7 and 1 were very close to the desired stoichiometry which was confirmed by energy dispersive X-ray analysis (EDAX). Ultraviolet visible near infrared (UV-VIS-NIR) absorption spectra of the synthesized CIGS nanoparticles revealed that the bandgap could be tuned over the range 1 to 1.7 eV by varying the Ga/(In+Ga) ratio.

  4. Flotation Separation of Cu-Zn Sulphide Ore by Sodium Hexametaphosphate%铜锌硫化矿浮选分离试验研究

    Institute of Scientific and Technical Information of China (English)

    李宁; 覃文庆; 焦芬; 魏茜

    2012-01-01

    通过单矿物浮选试验研究黄铜矿和铜离子活化后的铁闪锌矿在Z-200作用下的浮选行为,以及六偏磷酸钠对它们可浮性的影响.研究结果表明:用Z-200作捕收剂,六偏磷酸钠作抑制剂,黄铜矿和铜离子活化后的铁闪锌矿在pH 8~10范围内具有很好的浮选分离效果;实际矿石浮选试验表明,六偏磷酸钠和硫酸锌组合应用于铜锌分离中,对锌矿物能起到较好的抑制作用,从而达到铜锌分离的目的,但仍存在问题,需要进一步研究与优化.%The flotation behavior of chalcopyrite and Cu - aqtivitatded marmatite with O - isopropyl - N - ethyl thionocarbamate (Z - 200) and the effect of sodium hexametaphosphate on their float-ability were studied by single mineral tests. The results show that the selective separation of chalcopyrite from Cu - activitatded marmatite could be achieved at the pH value range of 8 -10 when using O - isopropyl - N - ethyl thionocarbamate as collector and sodium hexametaphosphate as depressant. The results of the real ore tests shows that the combination of sodium hexametaphosphate and zinc sulfate can depress zinc minerals effectively and outputs a good result in separating zinc from copper minerals, but with some problems which need further research and optimization.

  5. Effect of electromagnetic radiation on the physico-chemical properties of minerals; Efecto de la radiacion electromagnetica en las propiedades fisicoquimicas de los minerales

    Energy Technology Data Exchange (ETDEWEB)

    Lopez M, A.; Delgadillo G, J. A. [Universidad Autonoma de San Luis Potosi, Instituto de Metalurgia, Doctorado Institucional de Ingenieria y Ciencia de Materiales, Av. Sierra Leona 550, 78210 San Luis Potosi (Mexico); Vega C, H. R., E-mail: alopezm6@yahoo.com.mx [Universidad Autonoma de Zacatecas, Unidad Academica de Estudios Nucleares, Cipres No. 10, Fracc. La Penuela, 98068 Zacatecas (Mexico)

    2014-08-15

    The electromagnetic radiation effect represented by gamma rays was investigated through; chemical analysis, X-ray diffraction (XRD), scanning electron microscopy (Sem) and magnetization when applied at a dose of 0.5704 Gy (0.5704 J/ kg) at a feed relation of 18.40 ± 1.13 mGy/ h., in different minerals; in order to characterize the impact of the same from {sup 137}Cs in the physicochemical properties of these minerals. All the irradiated samples showed chemical stability at this stage undetectable other both in the XRD study and in the images analysis obtained by Sem; and at present almost the same chemical composition as the non-irradiated samples. So the same patterns of X-ray diffraction thereof, show a tendency to slightly lower the intensity of the most representative peaks of each mineral phase, which may be due to a decrease in crystallinity or preferential crystallographic orientation in crystals. In the micrographs analysis obtained by Sem on the irradiated samples, some holes (open pores) present in the particles were observed, mainly chalcopyrite and sphalerite lesser extent, seen this fact may be due to Compton Effect, in the radiation process. In relation to the magnetization property, a variation is obtained in the saturation magnetization (Ms) for the irradiated samples containing iron and more significantly in the chalcopyrite case. Therefore, with the radiation level used; slight changes occurring in the physical properties of minerals, whereas they remained stable chemically. These small changes may represent a signal that electromagnetic radiation applied at higher doses, is a viable option for improving the mineral processing. (author)

  6. Comparative study of structural and morphological properties of CuIn{sub 3}S{sub 5} and CuIn{sub 7}S{sub 11} materials

    Energy Technology Data Exchange (ETDEWEB)

    Khemiri, N., E-mail: naoufel_khemiri@yahoo.f [Laboratoire de Photovoltaique et Materiaux Semi-conducteurs, ENIT BP 37, Le belvedere 1002-Tunis (Tunisia); Kanzari, M. [Laboratoire de Photovoltaique et Materiaux Semi-conducteurs, ENIT BP 37, Le belvedere 1002-Tunis (Tunisia)

    2010-02-15

    CuIn{sub 3}S{sub 5} and CuIn{sub 7}S{sub 11} powders were prepared by solid-state reaction method using high-purity elemental copper, indium and sulphur. The films prepared from CuIn{sub 3}S{sub 5} and CuIn{sub 7}S{sub 11} powders were grown by thermal evaporation under vacuum (10{sup -6} Torr) on glass substrates at different substrate temperature Ts varying from room temperature to 200 deg. C. The powders and thin films were characterized for their structural properties by using X-ray diffraction (XRD) and energy dispersive X-ray (EDX). Both powders were polycrystalline with chalcopyrite and spinel structure, respectively. From the XRD data, we calculated the lattice parameters of the structure for the compounds. For CuIn{sub 3}S{sub 5} powder, we also calculated the cation-anion bond lengths. The effect of substrate temperature Ts on the structural properties of the films, such as crystal phase, preferred orientation and crystallinity was investigated. Indeed, X-ray diffraction analysis revealed that the films deposited at a room temperature (30 deg. C) are amorphous in nature while those deposited on heated were polycrystalline with a preferred orientation along (1 1 2) of the chalcopyrite phase and (3 1 1) of the spinel phase for CuIn{sub 3}S{sub 5} and CuIn{sub 7}S{sub 11} films prepared from powders, respectively. The morphology of the films was determined by atomic force microscopy AFM. The surface roughness and the grain size of the films increase on increasing the substrate temperature.

  7. Rare earth element and stable sulphur (δ 34S) isotope study of baryte-copper mineralization in Gulani area, Upper Benue Trough, NE Nigeria

    Science.gov (United States)

    El-Nafaty, Jalo Muhammad

    2015-06-01

    The geology of Gulani area comprises of inliers of diorite and granites of the Older Granite suite of the Pan-African (600 ± 150 Ma) age within Cretaceous sediments of the Bima, Yolde and Pindiga Formations and the Tertiary/Quaternary basalts of the Biu Plateau. Epigenetic baryte-copper mineralization occurs as baryte veins within the Bima and Yolde sandstones and fracture-filling malachite in Pan-African granites. Unaltered (distal), hydrothermally altered (proximal) granites and sandstones and vein materials (mineral separates of baryte and chalcopyrite/malachite mineralized rocks) were analysed for rare earth elements (REE) and stable sulphur isotopes. The REE patterns of the unaltered rocks (both granites and sandstones) indicate background values before mineralization, depicted by enriched LREE, depleted HREE and weak negative Eu anomalies typical of Pan-African (calc-alkaline) granites and sandstones derived from them. On the other hand, the hydrothermally altered and mineralized rocks and mineral separates show a distinct baryte and copper mineralization sub-systems characterized by similar high LREE and corresponding low HREE abundances. However, the negative Eu anomalies of the copper sub-system hosted by granites are typical of Pan-African (calc-alkaline) granites. The sandstone host rocks of the baryte sub-system are marked by positive Eu anomalies interpreted as reflecting the injection and subsequent deposition of the baryte-bearing hydrothermal solutions under oxidizing conditions. The baryte mineral separates show δ (34S) isotope range of 12.3-13.1‰ (CDT) indicating sulphur from sedimentary formation sources. This ruled out magmatic source of the sulphur from the nearby Tertiary/Quaternary volcanic rocks of the Biu Plateau as well as ocean water. However, the stable sulphur isotopic determination of the sulphides (chalcopyrite/malachite mineral separates and mineralized rocks) did not yield peaks and therefore no inferences drawn in this regard.

  8. A study of the trace sulfide mineral assemblages in the Stillwater Complex, Montana, USA

    Science.gov (United States)

    Aird, Hannah M.; Ferguson, Katherine M.; Lehrer, Malia L.; Boudreau, Alan E.

    2017-03-01

    The sulfide assemblages of the Stillwater Complex away from the well-studied ore zones are composed mainly of variable proportions of pyrrhotite, chalcopyrite, pentlandite, and ±pyrite. Excluding vein assemblages and those affected by greenschist and lower temperature alteration, the majority can be classified into two broad assemblages, defined here as pristine (multiphase, often globular in shape) or volatile-bearing (multiphase, high-temperature, volatile-rich minerals such as biotite, hornblende, or an unmixed calcite-dolomite assemblage). The volatile-bearing assemblages are mainly found within and below the J-M reef, where native copper and sphalerite are also locally present. Pristine sulfides are found throughout the stratigraphy. Both groups can be affected by apparent S loss in the form of pyrite being converted to magnetite and chalcopyrite to a Cu-Fe-oxide (delafossite), with little to no silicate alteration. An upward trend from pentlandite-rich to pyrrhotite-rich to pyrite-rich assemblages is observed in the footwall rocks in upper GN-I, and the same trend repeats from just below the reef and continues into the overlying N-II and GN-II. Modeling suggests that the sulfide Ni in the Peridotite Zone is largely controlled by silicate Ni. When taken together, observations are most readily explained by the remobilization of selected elements by a high-temperature fluid with the apparent loss of S > Cu > Ni. This could concentrate ore metals by vapor refining, eventually producing a platinum group element-enriched sulfide ore zone, such as the J-M reef.

  9. 青海纳日贡玛斑岩钼(铜)矿床:蚀变%THE NARIGONGMA PORPHYRY MOLYBDENUM (-COPPER) DEPOSIT IN QINGHAI PROVINCE: Alteration

    Institute of Scientific and Technical Information of China (English)

    卞雄飞

    2012-01-01

    The Narigongma porphyry molybdenum (-copper) deposit in Southern Qinghai Province is located in the northern part of Yulong metallogenic belt. Research on the deposit recognizes three types of alteration in the orefield, i.e. K-silicate alteration (biotite-K feldspar), propylitic alteration (chlorite-epidote ± calcite) and feldspar-destructive alteration (sericite ± kaolin ± calcite ± anhydrite). The metallogenesis is closely related to the quartz-molybdenite ± anhydrite ± chalcopyrite ± pyrite vein and molybdenite ± pyrite ± chalcopyrite vein.%通过对纳日贡玛斑岩钼(铜)矿床的蚀变类型的详细研究,识别了矿床蚀变的3种主要类型:钾硅酸盐化、青磐岩化和长石分解蚀变.前二者为矿区早期形成的蚀变,长石分解蚀变形成于晚期.钾硅酸盐化蚀变主要以黑云母化、钾长石化为特征,青磐岩化以脉状绿泥石、绿帘石、方解石等蚀变矿物的发育为基本特征,长石分解蚀变则发育绢云母、高岭土、方解石、硬石膏等矿物.研究认为矿化与石英-辉钼矿±硬石膏±黄铜矿±黄铁矿脉、辉钼矿±黄铁矿±黄铜矿脉有较为密切的联系.

  10. Formation of Archean batholith-hosted gold veins at the Lac Herbin deposit, Val-d'Or district, Canada: Mineralogical and fluid inclusion constraints

    Science.gov (United States)

    Rezeau, Hervé; Moritz, Robert; Beaudoin, Georges

    2017-03-01

    The Lac Herbin deposit consists of a network of mineralized, parallel steep-reverse faults within the synvolcanic Bourlamaque granodiorite batholith at Val-d'Or in the Archean Abitibi greenstone belt. There are two related quartz-tourmaline-carbonate fault-fill vein sets in the faults, which consist of subvertical fault-fill veins associated with subhorizontal veins. The paragenetic sequence is characterized by a main vein filling ore stage including quartz, tourmaline, carbonate, and pyrite-hosted gold, chalcopyrite, tellurides, pyrrhotite, and cubanite inclusions. Most of the gold is located in fractures in deformed pyrite and quartz in equilibrium with chalcopyrite and carbonates, with local pyrrhotite, sphalerite, galena, cobaltite, pyrite, or tellurides. Petrography and microthermometry on quartz from the main vein filling ore stage reveal the presence of three unrelated fluid inclusion types: (1) gold-bearing aqueous-carbonic inclusions arranged in three-dimensional intragranular clusters in quartz crystals responsible for the main vein filling stage, (2) barren high-temperature, aqueous, moderately saline inclusions observed in healed fractures, postdating the aqueous-carbonic inclusions, and considered as a remobilizing agent of earlier precipitated gold in late fractures, and (3) barren low-temperature, aqueous, high saline inclusions in healed fractures, similar to the crustal brines reported throughout the Canadian Shield and considered to be unrelated to the gold mineralization. At the Lac Herbin deposit, the aqueous-carbonic inclusions are interpreted to have formed first and to represent the gold-bearing fluid, which were generated contemporaneous with regional greenschist facies metamorphism. In contrast, the high-temperature aqueous fluid dissolved gold from the main vein filling ore stage transported and reprecipitated it in late fractures during a subsequent local thermal event.

  11. Elucidating the relationship between crystallo-chemistry and optical properties of CIGS nanocrystals

    Science.gov (United States)

    Ahmadi, Mahshid; Pramana, Stevin S.; Boothroyd, Chris; Lam, Yeng Ming

    2017-01-01

    The performance of solar cells fabricated using Cu(In,Ga)(S,Se)2 nanocrystal (NC) inks synthesized using the hot injection method has yielded efficiencies up to 12% recently. The efficiency of these devices is highly dependent on the chemical composition and crystallographic quality of the NCs. The former has been extensively discussed as it can be easily correlated to the optical properties of the film, but detailed crystallographic structure of these NCs has scarcely been discussed and it can influence both the optical and electrical properties. Hence both chemical composition and crystal structure should be explored for these NCs in order for this material to be further developed for application in thin film solar cells. In this work, a thorough investigation of the composition and crystal structure of CuIn x Ga1-x Se2 NCs synthesized using the hot injection method over the entire composition range (0 ≤ x ≤ 1) has been conducted. Raman spectroscopy of the NCs complements the information derived from x-ray diffraction (XRD) and electron probe microanalysis (EPMA). EPMA, which was carried out for the first time, indicates good controllability of the NC Ga/(In + Ga) ratio using this synthesis method. Raman spectroscopy reveals that CuInSe2 NCs are a mixture of chalcopyrite and sphalerite with disordered cations, whereas CuGaSe2 NCs are purely chalcopyrite. The lattice parameters determined from XRD were found to deviate from those calculated using Vegard’s law for all compositions. Hence, it can be deduced that the lattice is distorted in the crystal. The optical and electrochemical band gap of CuIn x Ga1-x Se2 NCs increases as the Ga content increases. The energy band gap deviates from the theoretical values, which could be related to the contribution from cation disordering and strain. These results help to tailor the opto-electrical properties of semiconductors, which inherently depend on the crystalline quality, strain and composition.

  12. Redox processes in subducting oceanic crust recorded by sulfide-bearing high-pressure rocks and veins (SW Tianshan, China)

    Science.gov (United States)

    Li, Ji-Lei; Gao, Jun; Klemd, Reiner; John, Timm; Wang, Xin-Shui

    2016-09-01

    The oxidized nature of the sub-arc mantle and hence arc magmas is generally interpreted as a result of the migration of subduction-related oxidizing fluids or melts from the descending slab into the mantle wedge. This is of particular importance seeing that the oxidization state of sub-arc magmas seems to play a key role in the formations of arc-related ore deposits. However, direct constraints on the redox state of subducted oceanic crust are sparse. Here, we provide a detailed petrological investigation on sulfide- and oxide-bearing eclogites, blueschists, micaschists, eclogite-facies and retrograde veins from the Akeyazi high-pressure (HP) terrane (NW China) in order to gain insight into the redox processes recorded in a subducting oceanic slab. Sulfides in these rocks are mainly pyrite and minor pyrrhotite, chalcopyrite, bornite, molybdenite, sphalerite and chalcocite, including exsolution textures of bornite-chalcopyrite intergrowth. Magnetite, ilmenite and pyrite occur as inclusions in garnet, whereas sulfides are dominant in the matrix. Large pyrite grains in the matrix contain inclusions of garnet, omphacite and other HP index minerals. However, magnetite replacing pyrite textures are commonly observed in the retrograded samples. The eclogite-facies and retrograde veins display two fluid events, which are characterized by an early sulfide-bearing and a later magnetite-bearing mineral assemblage, respectively. Textural and petrological evidences show that the sulfides were mainly formed during HP metamorphism. Mineral assemblage transitions reveal that the relative oxygen fugacity of subducted oceanic crust decreases slightly with increasing depths. However, according to oxygen mass balance calculations, based on the oxygen molar quantities ( nO2), the redox conditions remain constant during HP metamorphism. At shallow levels (arc mantle melts.

  13. Lead and neodymium isotopic results from metabasalts of the Haveri Formation, southern Finland: evidence for Palaeoproterozoic enriched mantle

    Directory of Open Access Journals (Sweden)

    Vaasjoki, M.

    1999-06-01

    Full Text Available Tholeiitic metabasalts and coexisting sulphides have been analysed for their Pb and Nd isotopic compositions from the Proterozoic Haveri Formation, which forms the basal unit of the Tampere Schist Belt in southern Finland. Ten whole rock samples analysed for Pb isotopes form a sublinear array which yields rather uncertain age estimates in the 1900-2000 Ma range and lies on the 207Pb/204Pb vs. 206Pb/204Pb diagram well below the average global lead evolution curve. The initial lead isotopic composition inferred from the whole rock data and measured on chalcopyrite is the least radiogenic obtained from the Svecofennian domain, and precludes involvement of old upper crustal material in basalt genesis. This together with the geochemical composition and initial eNd (1900 of +0.5±0.6 suggest that the Haveri mafic metavolcanic rocks were not derived from convective MORB-type mantle. The source was rather a mantle, which had been enriched in LREE for a considerable time period. Some chalcopyrite trace leads plot close to the whole rock array while others lie above it. This is interpreted as indicating two distinct mineralisation processes. The primary and major process involved lead which was cogenetic with the basalts, while the second mineralising fluid introduced radiogenic (high 207Pb upper crustal lead scavenged from the adjacent sedimentary rocks. The least radiogenic leads at Haveri and in the Outokumpu ophiolite complex some 300 km NE are similar and the two occurrences can be coeval. The preservation of original mantle material at Haveri may be interpreted as suggesting that continental crust had formed in the Tampere area 1900-2000 Ma ago.

  14. A study of the trace sulfide mineral assemblages in the Stillwater Complex, Montana, USA

    Science.gov (United States)

    Aird, Hannah M.; Ferguson, Katherine M.; Lehrer, Malia L.; Boudreau, Alan E.

    2016-07-01

    The sulfide assemblages of the Stillwater Complex away from the well-studied ore zones are composed mainly of variable proportions of pyrrhotite, chalcopyrite, pentlandite, and ±pyrite. Excluding vein assemblages and those affected by greenschist and lower temperature alteration, the majority can be classified into two broad assemblages, defined here as pristine (multiphase, often globular in shape) or volatile-bearing (multiphase, high-temperature, volatile-rich minerals such as biotite, hornblende, or an unmixed calcite-dolomite assemblage). The volatile-bearing assemblages are mainly found within and below the J-M reef, where native copper and sphalerite are also locally present. Pristine sulfides are found throughout the stratigraphy. Both groups can be affected by apparent S loss in the form of pyrite being converted to magnetite and chalcopyrite to a Cu-Fe-oxide (delafossite), with little to no silicate alteration. An upward trend from pentlandite-rich to pyrrhotite-rich to pyrite-rich assemblages is observed in the footwall rocks in upper GN-I, and the same trend repeats from just below the reef and continues into the overlying N-II and GN-II. Modeling suggests that the sulfide Ni in the Peridotite Zone is largely controlled by silicate Ni. When taken together, observations are most readily explained by the remobilization of selected elements by a high-temperature fluid with the apparent loss of S > Cu > Ni. This could concentrate ore metals by vapor refining, eventually producing a platinum group element-enriched sulfide ore zone, such as the J-M reef.

  15. The structural and material properties of CuInSe{sub 2} and Cu(In,Ga)Se{sub 2} prepared by selenization of stacks of metal and compound precursors by Se vapor for solar cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Dejene, F.B. [Department of Physics, University of the Free State, Private Bag X13, Phuthaditjhaba 9866 (South Africa)

    2009-05-15

    CuInSe{sub 2} films and related alloys were prepared by thermal evaporation of Cu, InSe and GaSe compounds instead of elemental sources. Band-gap tailoring in Cu(In,Ga)Se{sub 2}-based solar cells is an interesting path to improve their performance. In order to get comparable results, solar cells with Ga/(In+Ga) ratios x=0 and 0.3 were prepared, all with a simple two-step sequential evaporation process. The morphology of the resulting films grown at 550 C was characterized by the presence of large facetted chalcopyrite grains, which are typical for device quality material. It is important to note that absorber films with elemental gallium resulted in a significant decrease in the average grain size of the film. The X-ray diffraction (XRD) diffraction pattern of single-phase Cu(In,Ga)Se{sub 2} films depicts diffraction peaks shifting to higher 2{theta} values compared to that of pure CuInSe{sub 2}. The photoluminescence (PL) spectrum of Cu(In,Ga)Se{sub 2} thin films also depicts the presence of the peak at higher energy that is attributed to the incorporation of gallium into the chalcopyrite lattice. As the band gap of CIGS increases with gallium content, desirable effects of producing higher open-circuit voltage and low current density devices were achieved. A corresponding increase in device efficiency with gallium content caused by a higher fill factor was observed. The best results show passive area efficiencies of up to 10.2% and open-circuit voltage (V{sub oc}) up to 519 mV at a minimum band gap of 1.18 eV. (author)

  16. The structural and material properties of CuInSe2 and Cu (In,Ga)Se2 prepared by selenization of stacks of metal and compound precursors by Se vapor for solar cell applications

    Science.gov (United States)

    Dejene, F. B.

    2008-08-01

    CuInse2 films and related alloys were prepared by thermal evaporation of Cu, InSe and GaSe compounds instead of elemental sources. Band gap tailoring in Cu(In,Ga)Se2 based solar cells is an interesting path to improve their performance. In order to get comparable results solar cells with Ga/(In+Ga) ratios x =0 and 0.3 were prepared, all with a simple two-step sequential evaporation process. The morphology of the resulting films grown at 550°C was characterized by the presence of large facetted chalcopyrite grains, which are typical for device quality material. It is important to note that absorber films with elemental gallium resulted in a significant decrease in the average grain size of the film. The XRD diffraction pattern of a single-phase Cu(In,Ga)Se2 films depicts diffraction peaks shift to higher 2θ values compared to that of pure CuInSe2 . The PL spectrum of Cu(In,Ga)Se2 thin films also depicts the presence of the peak at higher energy that is attributed to the incorporation of gallium into the chalcopyrite lattice. As the band gap of CIGS increases with gallium content, desirable effects of producing higher open-circuit voltage and low-current density devices were achieved. A corresponding increase in device efficiency with gallium content caused by a higher fill factor was observed. The best results show passive area efficiencies of up to 10.2% and open circuit voltage (Voc) up to 519 mV at a minimum band gap of 1.18eV.

  17. Source of Ore-Forming Materials of Tongchang Copper Ore Deposit in Southern Shaanxi Province, China%陕南铜厂铜矿床成矿物质来源探讨

    Institute of Scientific and Technical Information of China (English)

    叶霖; 杨玉龙; 高伟; 刘铁庚

    2012-01-01

    陕南铜厂铜矿床是“勉—略—宁”矿集区内最具代表性的铜矿床,通过黄铜矿等单矿物及矿区地质体的微量与稀土元素地球化学对比研究发现:1)黄铜矿以富Ni、Zn和贫Co为特征,与晚元古代郭家沟组细碧岩类似,较闪长岩和钠长岩不同;矿床中存在轻稀土富集和稀土配分模式相对平坦两类黄铜矿,岩体内外接触带黄铁矿Co/Ni值差异表明其成矿物质具多源性;由矿区各地质体成矿元素背景可见,矿床成矿物质来源应以细碧岩为主、闪长岩为辅.2)黄铜矿Eu负异常明显,其δEu值明显低于闪长岩和细碧岩,这与成矿过程中富挥发分流体所形成云英岩化、钠长石化造成的Eu亏损有关,且黄铜矿Y/Ho值与钠长岩较为相似,暗示铜矿化与钠质交代作用关系密切.3)黄铜矿Co、Ni含量一般大于黄铁矿几倍到几十倍,与矽卡岩、斑岩、火山-次火山热液及火山-喷气型铜矿中黄铜矿差异明显,而与铜镍硫化物型矿床中黄铜矿类似,这可能与成矿作用继承了富Ni源区有关.该矿床成矿模式为:海西期,伴随着勉略洋盆闭合俯冲-碰撞形成勉略宁地区韧-脆性逆冲推覆构造、走滑断层,在区域变质流体与天水混合形成富碱和CO2的混合热液作用下,使地层——细碧岩和部分闪长岩中Cu等成矿物质大量析出,形成低温、低盐度成矿热液,沿矿区发育EW向与NE向两组韧性走滑断裂充填沉淀成矿.%The Tongchang deposit is the most typical copper deposit in Mianxian-Lueyang-Ningqiang (Mian-Lue-Ning) area in southern Shaanxi, China. By studying on trace elements and REEs geochemistry of chalcopyrite (pyrite) as well as geological bodies in the deposit, we can draw some conclusions as followings. Firstly, the chalcopyrite is characterized by enrichment of Ni and Zn, depletion of Co, which is similar to the spilite of Late Proterozoic Guojiagou Formaion, while different from diorite and

  18. Hydrothermal Fluid evolution in the Dalli porphyry Cu-Au Deposit: Fluid Inclusion microthermometry studies

    Directory of Open Access Journals (Sweden)

    Alireza Zarasvandi

    2015-10-01

    Full Text Available Introduction A wide variety of world-class porphyry Cu deposits occur in the Urumieh-Dohktar magmatic arc (UDMA of Iran.The arc is composed of calc-alkaline granitoid rocks, and the ore-hosting porphyry intrusions are dominantly granodiorite to quartz-monzonite (Zarasvandi et al., 2015. It is believed that faults played an important role in the emplacement of intrusions and subsequentporphyry-copper type mineralization (Shahabpour, 1999. Three main centers host the porphyry copper mineralization in the UDMA: (1 Ardestan-SarCheshmeh-Kharestan zone, (2 Saveh-Ardestan district; in the central parts of the UDMA, hosting the Dalli porphyry Cu-Au deposit, and (3 Takab-Mianeh-Qharahdagh-Sabalan zone. Mineralized porphyry coppersystems in the UDMA are restricted to Oligocene to Mioceneintrusions and show potassic, sericitic, argillic, propylitic and locally skarn alteration (Zarasvandi et al., 2005; Zarasvandi et al., 2015. In the Dalli porphyry deposit, four hydrothermal alteration zones, includingpotassic, sericitic, propylitic, and argillic types have been described in the two discrete mineralized areas, namely, northern and southern stocks. Hypogenemineralization includes chalcopyrite, pyrite, and magnetite, with minor occurrences of bornite.Supergene activity has produced gossan, oxidized minerals and enrichment zones. The supergene enrichment zone contains chalcocite and covellite with a 10-20 m thickness. Mineralization in the northern stock is mainly composed of pyrite and chalcopyrite. The aim of this study is the investigation and classification of hydrothermal veins and the constraining of physicochemical compositions of ore-forming fluids using systematic investigation of fluid inclusions. Materials and methods Twenty samples were collected from drill holes. Thin and polished sections were prepared from hydrothermal veins of thepotassic, sericitic and propylitic alteration zones. Samples used for fluid inclusion measurements were collected

  19. Metallogeny of The Sierra de Guanajuato Range, Central México

    Science.gov (United States)

    Pedro F., Z. D.

    2004-12-01

    The Sierra de Guanajuato Range (SGR), trending N315° at Central México, is an orographic feature extending over a distance of 80 km. SGR comprises three well defined lithostratigraphic units: (1) a cretaceous basement including an arc-derived terrane named Guanajuato Arc (GA) made of gabbro, diorite and basaltic pillowed lava, and volcano-sedimentary rocks belonging to Arperos fore-arc basin which are geochemically anomalous in Au (0.15 ppm), Ag (3 ppm), Cu (40 ppm), Pb (50 ppm) and Zn (15 ppm); (2) Early Tertiary intrusive rocks, e.g., Comanja Granite which is affected by the presence of tourmalinized (schörl) aplito-pegmatite dykes mineralized with rare earths elements, and (3) Eocene redbeds (1,500-2000 m) and Oligocene-Miocene volcanics cover. The metallogeny of the SGR shows a multiple origin in time and space: volcano-sedimentary, granitic and volcanic, being possible to define three metallogenic epochs: cretaceous, paleocene and oligocene. Cretaceous epoch includes: (a) volcanogenic massive sulphide deposits (VMS) of bimodal-siliclastic type belonging to León-Guanajuato district; wallrock of VMS is made of felsic-internediate volcanics and black argillite; at Los Gavilanes deposit paragenesis is next: chalcopyrite > sphalerite > galena, pyrite > pyrrhotite > marcasite; grade is as follows: Au: .02-.07 g/t; Ag: 157-18.5 g/t; Cu: 2.24-0.81%, Pb: 4.16-0.03%; Zn: 10.35-3.02 %; (b) lens-shaped stratiform bodies of massive pyrite (i. ex., San Ignacio prospect; ˜ 4,000 ton) of exhalative-sedimentary origin with chalcopyrite and sphalerite microveins. Paleocene epoch includes both quartz-cordierite-sanidine veins and replacement bodies of hydrothermal metamorphic filliation (W +Se-Bi, Pb, Zn, Cu), and pyrometasomatic bodies [Cu, Pb, Zn (Ag), W] which genetically are linked to Comanja Granite emplacement. The wallrock at El Maguey mine (35,000 ton; 0.6% WO3) is made of hornfel and the vein (1.8-3.2m width) has a banding structure made of : \\{quartz & K

  20. Optics of the CuGaSe{sub 2} solar cell for highly efficient tandem concepts; Optik der CuGaSe{sub 2}-Solarzelle fuer hocheffiziente Tandemkonzepte

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Martina

    2010-01-25

    A principle aim of solar cell research lies in optimizing the exploitation of the incident solar light. Yet, for single junction solar cells there exists an efficiency limit as described by Shockley and Queisser. The only concept realized so far to overcome this threshold is - apart from concentration - the multijunction solar cell. However, any kind of multijunction design poses new challenges: The upper wide-gap solar cell (top cell) needs to show efficient light absorption in the short-wavelength region. At the same time sufficient transmission for long-wavelength light is required which then needs to be absorbed effectively by the low-gap bottom cell. In tandem solar cells a proper light management in top and bottom solar cell is of great importance. This work focuses on chalcopyrite-based tandem solar cells. For the wide-bandgap IR-transparent ZnO:Al/i-ZnO/CdS/CuGaSe{sub 2}/SnO{sub 2}:F/glass solar cell an optical model has been established. Starting from modeling each of the individual layers building the stack the optical behavior of the complete thin film system of the top cell could be described. Carefully selected layer combinations and comparison of experimental and calculated data allowed for the attribution of transmission losses to the distinct material properties. Defects in the absorber are of crucial importance but also free carrier absorption in the window and in the transparent back contact contribute significantly to optical losses. The quantification of the losses was achieved by calculating the effects of reduced top cell transmission on the photo current of a simplified bottom cell. An extension of the optical model allowed to calculate the effective absorption in the individual layers and to determine reflection losses at the interfaces. From these results an optimized top cell stack was derived which is characterized by A) simulation of the monolithic integration, B) reduced layer thicknesses wherever possible from the electrical point of

  1. Geology and porphyry copper-type alteration-mineralization of igneous rocks at the Christmas Mine, Gila County, Arizona

    Science.gov (United States)

    Koski, Randolph A.

    1979-01-01

    igneous rocks is progressively more alkaline and silicic from basalt to granodiorite. Early (Stage I) chalcopyrite-bornite (-molybdenite) mineralization and genetically related K-silicate alteration are centered on the Christmas stock. K-silicate alteration is manifested by pervasive hornblende-destructive biotitization in the stock, biotitization of basaltic volcanic wall rocks, and a continuous stockwork of K-feldspar veinlets and quartz-K-feldspar veins in the stock and quartz-sulfide veins in volcanic rocks. Younger (Stage II) pyrite-chalcopyrite mineralization and quartz-sericite-chlorite alteration occur in a zone overlapping with but largely peripheral to the zone of Stage I stockwork veins. Within the Christmas intrusive complex, K-silicate-altered rocks in the central stock are flanked east and west by zones of fracture-controlled quartz-sericite alteration and strong pyritization. In volcanic rocks quartz-chlorite-pyrite-chalcopyrite veins are superimposed on earlier biotitization and crosscut Stage I quartz-sulfide veins. Beyond the zones of quartz-sericite alteration, biotite rhyodacite porphyry dikes contain the propylitic alteration assemblage epidote-chlorite-albite-sphene. Chemical analyses indicate the following changes during pervasive alteration of igneous rocks: (1) addition of Si, K, H, S, and Cu, and loss of Fe 3+ and Ca during intense biotitization of basalt; (2) loss of Na and Ca, increase of Fe3+/Fe2+, and strong H-metasomatism during sericitization of quartz diorite; and (3) increase in Ca, Na, and Fe3+/Fe2+, and loss of K during intense propylitization of biotite rhyodacite porphyry dikes. Thorough biotitization of biotite granodiorite porphyry in the Christmas stock was largely an isochemical process. Fluid-inclusion petrography reveals that Stage I veins are characterized by low to moderate populations of moderate-salinity and gas-rich inclusions, and sparse but ubiquitous halite-bearing inclusions. Moderate-salinity an

  2. Structural studies of mechano-chemically synthesized CuIn{sub 1-x}Ga{sub x}Se{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Vidhya, B., E-mail: vidhyabhojan@gmail.com [Department of Electrical Engineering, SEES, CINVESTAV-IPN, Mexico, D.F., C.P. 07360 (Mexico); Velumani, S. [Department of Electrical Engineering, SEES, CINVESTAV-IPN, Mexico, D.F., C.P. 07360 (Mexico); Arenas-Alatorre, Jesus A. [Institute of Physics, Universidad Nacional Autonoma de Mexico, A.P. 20-364, 01000 Mexico, D.F. (Mexico); Morales-Acevedo, Arturo; Asomoza, R. [Department of Electrical Engineering, SEES, CINVESTAV-IPN, Mexico, D.F., C.P. 07360 (Mexico); Chavez-Carvayar, J.A. [Instituto de investigaciones en Materiales, UNAM, Mexico, D.F. (Mexico)

    2010-10-25

    CuInGaSe{sub 2} is a I-III-VI{sub 2} semiconducting material of tetragonal chalcopyrite structure. It is a very prominent absorber layer for photovoltaic devices. Particle-based coating process for CIGS is considered to be promising technique with relatively simple procedures and low initial investment. In the present work CIGS nanoparticle precursors suitable for screen-printing ink has been prepared by ball milling. High purity elemental copper granules, selenium and indium powders and fine chips of gallium were used as starting materials. First the ball milling was carried out for CuIn{sub 1-x}Ga{sub x}Se{sub 2} (x = 0.5) with (i) 10 ml of ethyl alcohol (ii) 5 ml of tetra ethylene glycol (wet) and (iii) 1 ml of ethylene diamine (semi-dry) for a milling time of 3 h and the results are not stoichiometric. In order to obtain an improved stoichiometric composition dry ball milling of elemental sources for three different compositions of CuIn{sub 1-x}Ga{sub x}Se{sub 2} (x = 0.25, 0.5 and 0.75) has been carried out. X-ray diffraction analysis revealed the presence of (1 1 2), (2 2 0)/(2 0 4), (3 1 2)/(1 1 6), (4 0 0) and (3 3 2) reflections for all the milled powders. These reflections correspond to chalcopyrite structure of CIGS. Shift in peaks towards higher value of 2{theta} is observed with the increase in Ga composition. Average grain size calculated by Scherrer's formula is found to be around 13 nm for the dry samples milled for 1.5 h and 7-8 nm for the samples wet milled for 3 h. Lattice constants 'a' and 'c' are found to decrease with the increase in concentration of Gallium. FESEM analysis revealed a strong agglomeration of the particles and the particle size varied from 11 to 30 nm for the dry-milled samples. Composition of milled powders has been studied by energy dispersive X-ray analysis. TEM analysis revealed the presence of nanocrystalline particles and SAED pattern corresponds to (1 1 2), (2 2 0)/(2 0 4), (5 1 2)/(4 1 7) and (6

  3. Origin and evolution of mineralizing fluids and exploration of the Cerro Quema Au-Cu deposit (Azuero Peninsula, Panama) from a fluid inclusion and stable isotope perspective

    Science.gov (United States)

    Corral, Isaac; Cardellach, Esteve; Corbella, Merce; Canals, Angels; Griera, Albert; Gomez-Gras, David; Johnson, Craig A.

    2017-01-01

    Cerro Quema is a high sulfidation epithermal Au-Cu deposit with a measured, indicated and inferred resource of 35.98 Mt. @ 0.77 g/t Au containing 893,600 oz. Au (including 183,930 oz. Au equiv. of Cu ore). It is characterized by a large hydrothermal alteration zone which is interpreted to represent the lithocap of a porphyry system. The innermost zone of the lithocap is constituted by vuggy quartz with advanced argillic alteration locally developed on its margin, enclosed by a well-developed zone of argillic alteration, grading to an external halo of propylitic alteration. The mineralization occurs in the form of disseminations and microveinlets of pyrite, chalcopyrite, enargite, tennantite, and trace sphalerite, crosscut by quartz, barite, pyrite, chalcopyrite, sphalerite and galena veins.Microthermometric analyses of two phase (L + V) secondary fluid inclusions in igneous quartz phenocrysts in vuggy quartz and advanced argillically altered samples indicate low temperature (140–216 °C) and low salinity (0.5–4.8 wt% NaCl eq.) fluids, with hotter and more saline fluids identified in the east half of the deposit (Cerro Quema area).Stable isotope analyses (S, O, H) were performed on mineralization and alteration minerals, including pyrite, chalcopyrite, enargite, alunite, barite, kaolinite, dickite and vuggy quartz. The range of δ34S of sulfides is from − 4.8 to − 12.7‰, whereas δ34S of sulfates range from 14.1 to 17.4‰. The estimated δ34SΣS of the hydrothermal fluid is − 0.5‰. Within the advanced argillic altered zone the δ34S values of sulfides and sulfates are interpreted to reflect isotopic equilibrium at temperatures of ~ 240 °C. The δ18O values of vuggy quartz range from 9.0 to 17.5‰, and the δ18O values estimated for the vuggy quartz-forming fluid range from − 2.3 to 3.0‰, indicating that it precipitated from mixing of magmatic fluids with surficial fluids. The δ18O of kaolinite ranges from 12.7 to 18.1‰ and

  4. A tentative discussion on ore-controlling factors, ore genesis and metallogenic model of Houwanling Pb-Zn deposit in Hainan Province%海南省后万岭铅锌矿床控矿因素、矿床成因及成矿模式探讨

    Institute of Scientific and Technical Information of China (English)

    付王伟; 许德如; 傅杨荣; 杨昌松; 周迎春; 杨东生; 吴传军; 王智琳

    2012-01-01

    obtained abundant important information: course-grained pyrite and fractured pyrite were filled with chalcopyrite, indicating that some of the course-grained pyrite underwent faulting activities, and course-grained pyrite was generated earlier than chalcopyrite with mesh texture at a temperature of 300 ~ 400℃ ; skeletal texture resulted from replacement of course-grained pyrite by sphalerite, indicating that sphalerite was generated after course-grained pyrite; corona texture resulted from replacement of chalcopyrite by covellite, indicating that covellite was generated in the shallow part at a low temperature below 300℃ ; emulsion texture and grating texture resulted from the separation of chalcopyrite from sphalerite, indicating that chalcopyrite - sphalerite solid solution had a initial temperature of about 550℃ . Geological data reveal that the Houwanling Pb-Zn ore deposit probably underwent multistage mineralization and experienced at least more than four main stages of hydrothermal mineralization: ① the generation of course-grained pyrite at early stage of mineralization; ② the deposition of sphalerite mainly at the middle stage of mineralization; ③ the formation of chalcopyrite mainly at the middle or late stage of mineralization; ④ the generation of galena mainly at the late stage of mineralization. The ore-forming fluid might have been released from fractionating porphyry magma. The authors thus consider that the Houwanling Pb-Zn deposit is a hydrothermal vein-type deposit in peripheral or supergene location of the porphyry system, strictly controlled by NNW-nearly SN transtensional faults and formed in an extensional environment of post-collision in late Cretaceous. On such a basis, a metallogenic model to explain ore genesis of the Houwanling Pb-Zn ore deposit is put forward in this paper.

  5. Formation pathway of CuInSe2 nanocrystals for solar cells.

    Science.gov (United States)

    Kar, Mahaprasad; Agrawal, Rakesh; Hillhouse, Hugh W

    2011-11-02

    Copper, indium, and gallium chalcogenide nanocrystals (binary, ternary, and quaternary) have been used to fabricate high-efficiency thin-film solar cells. These solution-based methods are being scaled-up and may serve as the basis for the next generation of low-cost solar cells. However, the formation pathway to reach stoichiometric ternary CuInSe(2) or any chalcopyrite phase ternary or quaternary nanocrystal in the system has not been investigated but may be of significant importance to improving nanocrystal growth and discovering new methods of synthesis. Here, we present the results of X-ray diffraction, electron microscopy, compositional analysis, IR absorption, and mass spectrometry that reveal insights into the formation pathway of CuInSe(2) nanocrystals. Starting with CuCl, InCl(3), and elemental Se all dissolved in oleylamine, the overall reaction that yields CuInSe(2) involves the chlorination of the hydrocarbon groups of the solvent. Further, we show that the amine and alkene functional groups in oleylamine are not necessary for the formation of CuInSe(2) nanocrystals by conducting successful syntheses in 1-octadecene and octadecane. Hence, the role of oleylamine is not limited to nanocrystal size and morphology control; it also acts as a reactant in the formation pathway. Typically, the formation of copper selenide (CuSe) and indium selenide (InSe) nanocrystals precedes the formation of CuInSe(2) nanocrystals in oleylamine. But it was also found that Cu(2-x)Se (0 < x < 0.5) and In(2)Se(3) were the primary intermediates involved in the formation of CISe in a purely non-coordinating solvent such as 1-octadecene, which points to the surface-stabilization effect of the coordinating solvent on the less thermodynamically stable indium selenide (InSe) nanocrystals. We also show that the yield of the chalcopyrite phase of CuInSe(2) (as opposed to the sphalerite phase) can be increased by reacting CuSe nanocrystals with InCl(3).

  6. Study on the process mineralogy of Xiarihamu copper-nickel ore in Qinghai%青海夏日哈木铜镍矿石工艺矿物学研究

    Institute of Scientific and Technical Information of China (English)

    刘长征; 杨启安; 吴树宽; 谢海林; 徐修生; 于传兵; 王治安

    2016-01-01

    青海夏日哈木铜镍矿石属硫化镍矿石,含镍0.63%~0.80%,铜0.14%~0.20%,钴0.025%~0.028%,是主要回收对象.矿石矿物组成复杂,铜矿物以黄铜矿为主,少量的墨铜矿和微量的方黄铜矿及铜蓝;镍矿物以镍黄铁矿为主,有微量的紫硫镍矿、砷镍矿、辉砷镍矿及含钴的辉砷镍矿等;铁矿物主要为磁铁矿,微量赤铁矿及菱铁矿.铜、镍矿物嵌布特征复杂、嵌布粒度细微,普遍被脉石矿物包裹,同时铜、镍矿物自身相互紧密连生;矿石中含镁脉石矿物较多,具有质地柔软,容易泥化,自然可浮性好,吸附能力强的特点,将给铜、镍矿物的分选带来不利的影响.%Qinghai Xiarihamu deposit copper-nickel ore belongs to the nickel sulfide ore ,nickel 0 .63% ~0.80% ,copper 0 .14% ~0 .20% ,cobalt containing 0 .025% ~0 .028% ,is the main object of recycling .The deposit of copper-nickel ore mineral composition complex ,copper content is given priority to with chalcopyrite ,a small amount of the ink copper and Party chalcopyrite and copper blue;Nickel mineral is given priority to with nickel pyrite ,there are traces of purple sulfur nickel ,nickel arsenic ,fai arsenic nickel and fai arsenic containing cobait nickel ore ,etc .Iron ore are mainly magnetite ,trace hematite and siderite . The disseminated characteristics of copper and nickel minerals are complicated which embedded in superfine particle and are generally packed by the gangue minerals .Meanwhile the copper and nickel minerals are closely associated .There are amounts of magnesium gangue minerals in ores with characteristics of soft texture ,easily sliming ,good floatability high adsorption ability .These will bring seriously bad impact to the separation of copper and nickel ore .

  7. Methane origin and oxygen-fugacity evolution of the Baogutu reduced porphyry Cu deposit in the West Junggar terrain, China

    Science.gov (United States)

    Shen, Ping; Pan, HongDi

    2015-12-01

    Most porphyry copper deposits worldwide contain magnetite, hematite, and anhydrite in equilibrium with hypogene copper-iron sulfides (chalcopyrite, bornite) and have fluid inclusions with CO2 >> CH4 that are indicative of high fO2. In contrast, the Baogutu porphyry Cu deposit in the West Junggar terrain (Xinjiang, China) lacks hematite and anhydrite, contains abundant pyrrhotite and ilmenite in equilibrium with copper-iron sulfides (chalcopyrite), and has fluid inclusions with CH4 >> CO2 that are indicative of low fO2. The mineralized intrusive phases at Baogutu include the main-stage diorite stock and minor late-stage diorite porphyry dikes. The main-stage stock underwent fractional crystallization and country-rock assimilation-contamination, and consists of dominant diorite and minor gabbro and tonalite porphyry. The country rocks contain organic carbons (0.21-0.79 wt.%). The δ13CvPDB values of the whole rocks (-23.1 to -25.8 ‰) in the wall rocks suggest a sedimentary organic carbon source. The δ13CvPDB values of CH4 (-28.2 to -36.0 ‰) and CO2 (-6.8 to -20.0 ‰) in fluid inclusions require an organic source of external carbon and equilibration of their Δ13CCO2-CH4 values (8.2-25.0 ‰) at elevated temperatures (294-830 °C) suggesting a significant contribution of thermogenic CH4. Mineral composition data on the main-stage intrusions, such as clinopyroxene, hornblende, biotite, magnetite, ilmenite, sphene, apatite, and pyrrhotite, suggest that the primary magma at Baogutu was oxidized and became reduced after emplacement by contamination with country rocks. Mineral compositions and fluid inclusion gas compositions suggest that the redox state of the system evolved from log fO2 > FMQ + 1 in the magma stage, to log fO2 country rocks assimilation-contamination, to log fO2 > FMQ in the hydrothermal stage. Though oxidized magma was emplaced initially, assimilation-contamination of carbonaceous country rocks decreased its fO2 such that exsolved fluids contained

  8. Remobilisation features and structural control on ore grade distribution at the Konkola stratiform Cu-Co ore deposit, Zambia

    Science.gov (United States)

    Torremans, K.; Gauquie, J.; Boyce, A. J.; Barrie, C. D.; Dewaele, S.; Sikazwe, O.; Muchez, Ph.

    2013-03-01

    The Konkola deposit is a high grade stratiform Cu-Co ore deposit in the Central African Copperbelt in Zambia. Economic mineralisation is confined to the Ore Shale formation, part of the Neoproterozoic metasedimentary rocks of the Katanga Supergroup. Petrographic study reveals that the copper-cobalt ore minerals are disseminated within the host rock, sometimes concentrated along bedding planes, often associated with dolomitic bands or clustered in cemented lenses and in layer-parallel and irregular veins. The hypogene sulphide mineralogy consists predominantly of chalcopyrite, bornite and chalcocite. Based upon relationships with metamorphic biotite, vein sulphides and most of the sulphides in cemented lenses were precipitated during or after biotite zone greenschist facies metamorphism. New δ34S values of sulphides from the Konkola deposit are presented. The sulphur isotope values range from -8.7‰ to +1.4‰ V-CDT for chalcopyrite from all mineralising phases and from -4.4‰ to +2.0‰ V-CDT for secondary chalcocite. Similarities in δ34S for sulphides from different vein generations, earlier sulphides and secondary chalcocite can be explained by (re)mobilisation of S from earlier formed sulphide phases, an interpretation strongly supported by the petrographic evidence. Deep supergene enrichment and leaching occurs up to a km in depth, predominantly in the form of secondary chalcocite, goethite and malachite and is often associated with zones of high permeability. Detailed distribution maps of total copper and total cobalt contents of the Ore Shale formation show a close relationship between structural features and higher copper and lower cobalt contents, relative to other areas of the mine. Structural features include the Kirilabombwe anticline and fault zones along the axial plane and two fault zones in the southern limb of the anticline. Cobalt and copper behave differently in relation to these structural features. These structures are interpreted to have

  9. Barite from the Saf'yanovka VMS deposit (Central Urals) and Semenov-1 and Semenov-3 hydrothermal sulfide fields (Mid-Atlantic Ridge): a comparative analysis of formation conditions

    Science.gov (United States)

    Safina, Nataliya P.; Melekestseva, Irina Yu.; Nimis, Paolo; Ankusheva, Nataliya N.; Yuminov, Anatoly M.; Kotlyarov, Vasily A.; Sadykov, Sergey A.

    2016-04-01

    Different genetic types of barite from colloform and clastic pyrite-rich ores from the weakly metamorphic Saf'yanovka volcanogenic massive sulfide (VMS) deposit (Central Urals) were studied in comparison with barite from the Semenov-1 and Semenov-3 seafloor hydrothermal fields (mid-Atlantic Ridge). Hydrothermal barite generally occurs as radial aggregates of tabular crystals in contrast to compact aggregates of tabular crystals with stylolite boundaries of anadiagenetic barite from the Saf'yanovka clastic ores. The Sr content in barite shows no relationship with the genetic types. The δ34S values of hydrothermal barite from both ancient and modern colloform sulfides match those of Silurian-Devonian and contemporary seawater, respectively. The lower δ34S (avg +19.6 ‰) of hydrothermal barite from the Semenov-3 clastic sulfides indicates light sulfur contribution from oxidation of fluid H2S. The higher δ34S (avg +28.1 ‰) of anadiagenetic barite from the Saf'yanovka clastic ores reflects partial thermochemical reduction of seawater sulfate. Hydrothermal barite from the Saf'yanovka and Semenov-1 colloform ores formed from low- to moderate- T (172-194 °C and 83-233 °C, respectively) relatively low salinity (1.6-4.5 and 0.6-3.8 wt% NaCleq, respectively) fluids, which underwent phase separation. Hydrothermal barite from Semenov-3 clastic sulfides associated with chalcopyrite crystallized from higher- T (266-335 °C) higher-salinity (4.8-9.2 wt% NaCleq.) fluids. The high salinity may indicate a contribution from a magmatic fluid. Anadiagenetic barite from Saf'yanovka was formed from moderate- T (140-180 °C), low- to moderate-salinity (1.4-5.4 wt% NaCleq) pore fluids. Combining our new data with those for other seafloor hydrothermal barite occurrences, the following systematics can be defined. Barite associated with pyrite-rich sulfides forms at relatively low to moderate temperatures (<230 °C), barite associated with polymetallic-rich sulfides forms at moderately

  10. Post-collisional magmatism and ore-forming systems in the Menderes massif: new constraints from the Miocene porphyry Mo-Cu Pınarbaşı system, Gediz-Kütahya, western Turkey

    Science.gov (United States)

    Delibaş, Okan; Moritz, Robert; Chiaradia, Massimo; Selby, David; Ulianov, Alexey; Revan, Mustafa Kemal

    2017-01-01

    The Pınarbaşı Mo-Cu prospect is hosted within the Pınarbaşı intrusion, which is exposed together with the NW-SE-trending Koyunoba, Eğrigöz, and Baklan plutons along the northeastern border of the Menderes massif. The Pınarbaşı intrusion predominantly comprises monzonite, porphyritic granite, and monzodiorite. All units of the Pınarbaşı intrusion have sharp intrusive contacts with each other. The principal mineralization style at the Pınarbaşı prospect is a porphyry-type Mo-Cu mineralization hosted predominantly by monzonite and porphyritic granite. The porphyry type Mo-Cu mineralization consists mostly of stockwork and NE- and EW-striking sub-vertical quartz veins. Stockwork-type quartz veins hosted by the upper parts of the porphyritic granite within the monzonite, are typically enriched in chalcopyrite, molybdenite, pyrite, and limonite. The late NE- and EW-striking normal faults cut the stockwork vein system and control the quartz-molybdenite-chalcopyrite-sphalerite-fahlore-galena veins, as well as molybdenite-hematite-bearing silicified zones. Lithogeochemical and whole-rock radiogenic isotope data (Sr, Nd and Pb) of the host rocks, together with Re-Os molybdenite ages (18.3 ± 0.1 Ma - 18.2 ± 0.1 Ma) reveal that the monzonitic and granitic rocks of the Pınarbaşı intrusion were derived from an enriched lithospheric mantle-lower crust during Oligo-Miocene post-collisional magmatism. The lithospheric mantle was metasomatised by fluids and subducted sediments, and the mantle-derived melts interacted with lower crust at 35-40 km depth. This mechanism explains the Mo and Cu enrichments of the Pınarbaşı intrusion during back-arc magmatism. We conclude that the melt of the Pınarbaşı intrusion could have rapidly ascended to mid-crustal levels, with only limited crustal assimilation along major trans-lithospheric faults as a result of thinning of the middle to upper crust during regional extension, and resulted in the development of porphyry

  11. Mineralizing conditions and source fluid composition of base metal sulfides in the Lon District, southeastern Iceland

    Science.gov (United States)

    Kremer, C. H.; Thomas, D.; García del Real, P.; Zierenberg, R. A.; Bird, D. K.

    2014-12-01

    Hydrothermal base metal mineralization is rare in Iceland due to the scarcity of evolved magma bodies that discharge metal-rich aqueous fluids into bedrock. One exception is the Lon District of southeastern Iceland, where explosively emplaced rhyolitic breccias host base metal sulfide minerals. We performed petrographic, fluid inclusion, and stable isotope analyses on samples collected in Lon to constrain the conditions of sulfide mineral formation. Based on outcrop and hand sample observations, hot, early-stage hydrothermal fluids precipitated sulfide minerals, quartz, and epidote in rhyolitic breccia and basalt flows. Cooler late-stage fluids precipitated carbonates and quartz in rhyolitic breccia and basalt flows. The order of precipitation of the sulfides was: galena, sphalerite, then chalcopyrite. Homogenization temperatures of liquid-dominated multi-phase fluid inclusions in hydrothermal early-stage quartz coeval with chalcopyrite cluster around 303 °C and 330 °C, indicating precipitation of metallic sulfides in two main hydrothermal fluid pulses early in the period of hydrothermal activity in the Lon District. Freezing point depression analyses of fluid inclusions in quartz show that the sulfide minerals precipitated from a solution that was 4 wt. % NaCl. The 𝛿34S values of sulfides indicate that early-stage hydrothermal sulfur was derived from igneous rocks, either through leaching by non-magmatic hydrothermal fluids or by exsolution of magmatic waters. Early stage epidote 𝛿D values were on average -65.96 per mil, about 14 per mil higher than reported values in epidotes from elsewhere in southeastern Iceland. The 𝛿13C and 𝛿18O values of late-stage carbonates indicate that late stage hydrothermal fluids were meteoric in origin. Collectively, fluid inclusion and stable isotope analyses suggest that early-stage aqueous fluids derived from a mixture of magmatic waters exsolved from the proximal Geitafell intrusion and meteoric

  12. Chemical and sulphur isotope compositions of pyrite in the Jaduguda U (-Cu-Fe) deposit, Singhbhum shear zone, eastern India: Implications for sulphide mineralization

    Science.gov (United States)

    Pal, Dipak C.; Sarkar, Surajit; Mishra, Biswajit; Sarangi, A. K.

    2011-06-01

    The Jaduguda U (-Cu-Fe) deposit in the Singhbhum shear zone has been the most productive uranium deposit in India. Pyrite occurs as disseminated grains or in sulphide stringers and veins in the ore zone. Veins, both concordant and discordant to the pervasive foliation, are mineralogically either simple comprising pyrite ± chalcopyrite or complex comprising pyrite + chalcopyrite + pentlandite + millerite. Nickel-sulphide minerals, though fairly common in concordant veins, are very rare in the discordant veins. Pyrite in Ni-sulphide association is commonly replaced by pentlandite at the grain boundary or along micro-cracks. Based on concentrations of Co and Ni, pyrite is classified as: type-A - high Co (up to 30800 ppm), no/low Ni; type-B - moderate Co (up to 16500 ppm) and moderate to high Ni (up to 32700 ppm); type-C - no/low Co and high Ni (up to 43000 ppm); type-D - neither Co nor Ni. Textural and compositional data of pyrites suggest that the hydrothermal fluid responsible for pre-/early-shearing mineralization evolved from Co-rich to Ni-rich and the late-/post-shearing fluid was largely depleted in minor elements. Sulphur isotope compositions of pyrite mostly furnish positive values ranging between -0.33 and 12.06‰. Composite samples of pyrites with only type-A compositions and mixed samples of type-A and type-B are consistently positive. However, pyrite with mixed type-A and type-C and pyrite with type-D compositions have negative values but close to 0‰. By integrating minor element and sulphur isotope compositions of pyrite in conjunction with other published data on the Jaduguda deposit, it is proposed that reduced sulphur for the precipitation of most pyrites (type-A, type-B) was likely derived from isotopically heavy modified seawater. However, some later sulphur might be magmatic in origin remobilized from existing sulphides in the mafic volcanic rocks in the shear zone.

  13. Deciphering a multistage history affecting U-Cu(-Fe) mineralization in the Singhbhum Shear Zone, eastern India, using pyrite textures and compositions in the Turamdih U-Cu(-Fe) deposit

    Science.gov (United States)

    Pal, Dipak C.; Barton, Mark D.; Sarangi, A. K.

    2009-01-01

    The ˜200-km-long intensely deformed Singhbhum Shear Zone (SSZ) in eastern India hosts India’s largest U and Cu deposits and related Fe mineralization. The SSZ separates an Archaean cratonic nucleus to the south from a Mesoproterozoic fold belt in the North and has a complex geologic history that obscures the origin of the contained iron-oxide-rich mineral deposits. This study investigates aspects of the history of mineralization in the SSZ by utilizing new petrographic and electron microprobe observations of pyrite textures and zoning in the Turamdih U-Cu(-Fe) deposit. Mineralization at Turamdih is hosted in intensively deformed quartz-chlorite schist. Sulfides and oxides include, in inferred order of development: (a) magmatic Fe(-Ti-Cr) oxide and Fe-Cu(-Ni) sulfide minerals inferred to be magmatic (?) in origin; followed by (b) uranium, Fe-oxide, and Fe-Cu(-Co) sulfide minerals that predate most or all ductile deformation, and are inferred to be of hydrothermal origin; and (c) Fe-Cu sulfides that were generated during and postdating ductile deformation. These features are associated with the formation of three compositionally and texturally distinct pyrites. Pyrite (type-A), typically in globular-semiglobular composite inclusions of pyrite plus chalcopyrite in magnetite, is characterized by very high Ni content (up to 30,700 ppm) and low Co to Ni ratios (0.01-0.61). The textural and compositional characteristics of associated chalcopyrite and rare pyrrhotite suggest that this pyrite could be linked to the magmatic event via selective replacement of magmatic pyrrhotite. Alternatively, this pyrite and associated sulfide inclusions might be cogenetic with hydrothermal Fe-oxide. Type-B pyrite that forms elongate grains and irregular relics and cores of pyrite with high Co contents (up to 23,630 ppm) and high Co to Ni ratios (7.2-140.9) are interpreted to be related to hydrothermal mineralization predating ductile deformation. A third generation of pyrite (type C

  14. Gold deposition on pyrite and the common sulfide minerals: An STM/STS and SR-XPS study of surface reactions and Au nanoparticles

    Science.gov (United States)

    Mikhlin, Yuri L.; Romanchenko, Alexander S.

    2007-12-01

    Gold species spontaneously deposited on pyrite and chalcopyrite, pyrrhotite, galena, sphalerite from HAuCl 4 solutions at room temperature, as well as the state of the reacted mineral surfaces have been characterized using synchrotron radiation X-ray photoelectron spectroscopy (SR-XPS), scanning tunneling microscopy and tunneling spectroscopy (STM/STS). The deposition of silver from 10 -4 M AgNO 3 has been examined for comparison. Gold precipitates as metallic nanoparticles (NPs) from about 3 nm to 30 nm in diameter, which tends to aggregate forming larger particles, especially on pyrite. The Au 4f binding energies increase up to 1 eV with decreasing size of individual Au 0 NPs, probably due to the temporal charging in the final state. Concurrently, a positive correlation between the tunneling current and the particle size was found in STS. Both these size effects were observed for unusually large, up to 20 nm Au particles. In contrast, silver deposited on the minerals as nanoparticles of semiconducting sulfide showed no shifts of photoelectron lines and different tunneling spectra. The quantity of gold deposited on pyrite and other minerals increased with time; it was lower for fracture surfaces and it grew if minerals were moderately pre-oxidized, while the preliminary leaching in Fe(III)-bearing media inhibited the following Au deposition. After the contact of polished minerals with 10 -4 M AuCl4- solution (pH 1.5) for 10 min, the gold uptake changed in the order CuFeS 2 > ZnS > PbS > FeAsS > FeS 2 > Fe 7S 8. It was noticed that the open circuit (mixed) potentials of the minerals varied in approximately the same order, excepting chalcopyrite. We concluded that the potentials of minerals were largely determined by Fe(II)/Fe(III) couple, whereas the reduction of gold complexes had a minor effect. As a result, the deposition of gold, although it proceeded via the electrochemical mechanism, increased with decreasing potential. This suggests, in particular, that the

  15. Deposition and characterization of graded Cu(In{sub 1-x}Ga{sub x})Se{sub 2} thin films by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Babu, B.J. [Department of Electrical Engineering-SEES, CINVESTAV-IPN, Avenida IPN 2508, San Pedro Zacatenco, D.F. C.P 07360 (Mexico); Institute of Molecules and Materials, UMR-CNRS 6283, Université du Maine, Avenue O. Messiaen, F-72085 Le Mans (France); Velumani, S., E-mail: velu@cinvestav.mx [Department of Electrical Engineering-SEES, CINVESTAV-IPN, Avenida IPN 2508, San Pedro Zacatenco, D.F. C.P 07360 (Mexico); College of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of); Kassiba, A. [Institute of Molecules and Materials, UMR-CNRS 6283, Université du Maine, Avenue O. Messiaen, F-72085 Le Mans (France); Asomoza, R. [Department of Electrical Engineering-SEES, CINVESTAV-IPN, Avenida IPN 2508, San Pedro Zacatenco, D.F. C.P 07360 (Mexico); Chavez-Carvayar, J.A. [Instituto Investigaciones en Materiales-UNAM, Ciudad Universitario, D.F.Mexico (Mexico); Yi, Junsin, E-mail: yi@yurim.skku.ac.kr [College of Information and Communication Engineering, Sungkyunkwan University, Suwon 440-746 (Korea, Republic of)

    2015-07-15

    Cu(In{sub 1-x}Ga{sub x})Se{sub 2} (CIGS) thin films and their graded (x = 1 to 0) layer were grown on soda lime glass substrates using chemical spray pyrolysis (CSP) at different substrate temperatures (T{sub s}). After optimization of T{sub s}, depositions were carried out at different gallium composition (x) at optimized temperature of 350 °C. All the films deposited at T{sub s} ≥ 350 °C were polycrystalline chalcopyrite structure, with a preferential orientation of (112), including the graded layer. With increase in x, lattice parameters a and c were observed to decrease. Line scan of the CIGS layer showed intersection of gallium and indium concentrations, revealing the graded nature of the film. Composition dependence of Raman peak for CuInSe{sub 2} (CIS) deposited by CSP was analyzed. Optical transmittance at a wavelength of 800 nm of the film with x = 0 (CIS) (30%) was found lower than that of the film grown with x = 0.82 (CIGS) (50%). Cusp-shape of the resistivity was observed with an increase of x leading to steep rise in resistivity of the films (1.61–71.68 Ω-cm) till x = 0.42 and then decreased to 4.78 Ω-cm at x = 0.82. Carrier concentrations of the films were evaluated in the order of 10{sup 16}–10{sup 19} cm{sup −3} with p-type conductivity. These results indicate that graded CIGS thin films with modulated gallium composition can be prepared by CSP. - Graphical abstract: Display Omitted - Highlights: • Optimization of the spray deposition system for device grade chalcopyrite CIGS films. • Optimized substrate temperature to obtain single-phase CIGS by spray deposition. • Detailed report on compositional dependence of CuInSe{sub 2} (CIS) thin films. • Systematic analysis of the influence of Ga in CIS by spray deposition. • Bowing parameter is extracted from the experiment values.

  16. Study of the growth of CuAlS{sub 2} thin films on oriented silicon (111)

    Energy Technology Data Exchange (ETDEWEB)

    Brini, R. [Laboratoire de Photovoltaique et Materiaux Semiconducteurs.(LPMS), Ecole Nationale d' ingenieurs de Tunis (ENIT), BP 37 le Belvedere 1002 Tunis (Tunisia)], E-mail: Brini_rawdha@yahoo.fr; Schmerber, G. [Institut de Physique et Chimie des Materiaux de Strasbourg (IPCMS) UMR7504 CNRS-ULP, 23 rue du Loess, BP 43, 67034 Strasbourg Cedex 2 (France); Kanzari, M. [Laboratoire de Photovoltaique et Materiaux Semiconducteurs.(LPMS), Ecole Nationale d' ingenieurs de Tunis (ENIT), BP 37 le Belvedere 1002 Tunis (Tunisia); Werckmann, J. [Institut de Physique et Chimie des Materiaux de Strasbourg (IPCMS) UMR7504 CNRS-ULP, 23 rue du Loess, BP 43, 67034 Strasbourg Cedex 2 (France); Rezig, B. [Laboratoire de Photovoltaique et Materiaux Semiconducteurs.(LPMS), Ecole Nationale d' ingenieurs de Tunis (ENIT), BP 37 le Belvedere 1002 Tunis (Tunisia)

    2009-02-02

    Within the chalcopyrite family the sulphur based compounds CuMS{sub 2} (M = In, Ga, Al) have attracted much interest in recent years because they show a direct wide band-gap covering from E{sub gap} = 1.53 eV (CuInS{sub 2}) over E{sub gap} = 2.43 eV (CuGaS{sub 2}) to E{sub gap} = 3.49 eV (CuAlS{sub 2}). Therefore they are particularly suitable for optoelectronic as well as photovoltaic applications. The CuAlS{sub 2} semiconductor is one of these compounds and has good luminescent properties and a wide direct gap of 3.5 eV making it suitable for the use as material for light-emitting devices in the blue region of the spectrum. To dig up fully its potential a better understanding of the fundamental properties of the CuAlS{sub 2} film itself is essential, which could be achieved from high-quality single-crystalline materials. So, the aim of this work has been to study the growth of multilayer CuAlS{sub 2} thin films on Si(111) substrates at a substrate temperature of 723 K. One, two and three layers with 60, 120 and 180 nm thicknesses, respectively, were deposited on Si(111) substrate. The effect of the CuAlS{sub 2} layer numbers on the structure, morphology and optical properties of the samples was investigated. The X-ray diffraction studies revealed that all the samples are polycrystalline in nature, single CuAlS{sub 2} phase and exhibiting chalcopyrite structure with a preferred orientation along the (112) direction. However, the sample with three CuAlS{sub 2} layers exhibit the highly oriented (112) plane with grain sizes of 80 nm. So we show that this experimental process affects significantly the structural properties of the CuAlS{sub 2} films. Raman spectroscopic measurements indicated five prominent peaks at 193, 205, 325, 335 and 370 cm{sup -1}. The possible origin of the 370 cm{sup -1} peak was investigated and was found to be some local vibration in the structure. The peaks at 193-205 and 335 cm{sup -1} were ascribed to A{sub 1} and B{sub 2} modes

  17. Simulation of acid mine drainage generation around Küre VMS Deposits, Northern Turkey

    Science.gov (United States)

    Demirel, Cansu; Kurt, Mehmet Ali; Çelik Balci, Nurgül

    2015-04-01

    This study investigated comparative leaching characteristics of acidophilic bacterial strains under shifting environmental conditions at proposed two stages as formation stage or post acidic mine drainage (AMD) generation. At the first stage, initial reactions associated with AMD generation was simulated in shaking flasks containing massive pyritic chalcopyrite ore by using a pure strain Acidithiobacillus ferrooxidans and a mixed culture of Acidithiobacillus sp. mostly dominated by A. ferrooxidans and A. thiooxidans at 26oC. At the second stage, long term bioleaching experiments were carried out with the same strains at 26oC and 40oC to investigate the leaching characteristics of pyritic chalcopyrite ore under elevated heavy metal and temperature conditions. During the experiments, physicochemical characteristics (e.i. Eh, pH, EC) metal (Fe, Co, Cu, Zn) and sulfate concentration of the experimental solution were monitored during 180 days. Significant acid generation and sulfate release were determined during bioleaching of the ore by mixed acidophilic cultures containing both iron and sulfur oxidizers. In the early stage of the experiments, heavy metal release from the ore was caused by generation of acid due to accelerated bacterial oxidation of the ore. Generally high concentrations of Co and Cu were released into the solution from the experiments conducted by pure cultures of Acidithiobacillus ferrooxidans whereas high Zn and Fe was released into the solution from the mixed culture experiments. In the later stage of AMD generation and post AMD, chemical oxidation is accelerated causing excessive amounts of contamination, even exceeding the amounts resulted from bacterial oxidation by mixed cultures. Acidithibacillus ferrooxidans was found to be more effective in leaching Cu, Fe and Co at higher temperatures in contrary to mixed acidophiles that are more prone to operate at optimal moderate conditions. Moreover, decreasing Fe values are noted in bioleaching

  18. Geochemical element mobility during the hydrothermal alteration in the Tepeoba porphyry Cu-Mo-Au deposits at Balikesir, NW Turkey

    Science.gov (United States)

    Abdelnasser, Amr; Kiran Yildirim, Demet; Doner, Zeynep; Kumral, Mustafa

    2016-04-01

    The Tepeoba porphyry Cu-Mo-Au deposit represents one of the important copper source and mineral deposits in the Anatolian tectonic belt at Balikesir province, NW Turkey. It considered as a vein-type deposit locally associated with intense hydrothermal alteration within the brecciation, quartz stockwork veining, and brittle fracture zones in the main host rock that represented by hornfels, as well as generally related to the shallow intermediate to silicic intrusive Eybek pluton. Based on the field and geologic relationships and types of ore mineral assemblages and the accompanied alteration types, there are two mineralization zones; hypogene (primary) and oxidation/supergene zones are observed associated with three alteration zones; potassic, phyllic, and propylitic zones related to this porphyry deposit. The phyllic and propylitic alterations locally surrounded the potassic alteration. The ore minerals related to the hypogene zone represented by mostly chalcopyrite, Molybdenite, and pyrite with subordinate amount of marcasite, enargite, and gold. On the other hand they include mainly cuprite with chalcopyrite, pyrite and gold as well as hematite and goethite at the oxidation/supergene zone. This study deals with the quantitative calculations of the mass/volume changes (gains and losses) of the major and trace elements during the different episodes of alteration in this porphyry deposit. These mass balance data reveal that the potassic alteration zone that the main Cu- and Mo-enriched zone, has enrichment of K, Si, Fe, and Mg, and depletion of Na referring to replacement of plagioclase and amphibole by K-feldspar, sericite and biotite. While the propylitic alteration that is the main Mo- and Au-enriched zone is accompanied with K and Na depletion with enrichment of Si, Fe, Mg, and Ca forming chlorite, epidote, carbonate and pyrite. On the other hand the phyllic alteration that occurred in the outer part around the potassic alteration, characterized by less amount

  19. Concentration Tests for a High Silicon Copper-sulfur Mine%某高硅铜硫矿石分选试验

    Institute of Scientific and Technical Information of China (English)

    宁发添; 冯忠伟

    2011-01-01

    广西某高硫铜矿石中滑石等易浮硅质矿物含量高,现场采用弱磁选-浮铜-浮硫工艺流程进行分选,除弱磁选能较好地刚收磁黄铁矿外,黄铜矿浮选和黄铁矿浮选均因易浮硅质矿物的干扰而难以获得合格精矿.为此,在大量探索试验的基础上,采用弱磁选-黄铜矿和硅质矿物混合浮选-混浮精矿铜硅摇床分离-混浮尾矿浮黄铁矿的工艺流程处理该矿石,获得了磁选硫精矿硫品位和回收率分别为38.69%和64.48%,浮选硫精矿硫品位和网收率分别为44.57%和30.99%,铜精矿铜品位和回收率分别为13.87%和63.89%的良好试验指标,有效地综合回收了铜、硫矿物.%A certain high-sulfur copper ore in Guangxi contains high content of easy floating siliceous mineral,such as talc. The process of low intensity magnetic separation-copper floating-sulfur floating is carried out on the field. There,except for pyrrhotite well recovered by weak magnetic separation,it is difficult to obtain the qualified concentrate from flotation of chalcopyrite and pyrite due to the interference of silica minerals. Based on a large number of tests ,the process of low intensity magnetic separation-mixing flotation of chalcopyrite and siliceous minerals-shaking table separation for mixing flotation of silicon and copper concentrate - mixing flotation of pyrite from tailings is adopted to treat this ore. By this way,sulfur concentrate with S grade and recovery of 38.69% and 64. 48% by magnetic separation,and 44. 57% and 30. 99% by flotation,and copper concentrate with Cu grade and recovery of 13.87% and 63. 89% are realized respectively. So the copper and sulfur minerals can be effectively recovered.

  20. Theoretical Electron Density Distributions for Fe- and Cu-Sulfide Earth Materials: A Connection between Bond Length, Bond Critical Point Properties, Local Energy Densities, and Bonded Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Gibbs, Gerald V.; Cox, David F.; Rosso, Kevin M.; Ross, Nancy L.; Downs, R. T.; Spackman, M. A.

    2007-03-01

    Bond critical point and local energy density properties together with net atomic charges were calculated for theoretical electron density distributions, F(r), generated for a variety of Fe and Cu metal-sulfide materials with high- and low-spin Fe atoms in octahedral coordination and high-spin Fe atoms in tetrahedral coordination. The electron density, F(rc), the Laplacian, 32F(rc), the local kinetic energy, G(rc), and the oxidation state of Fe increase as the local potential energy density, V(rc), the Fe-S bond lengths, and the coordination numbers of the Fe atoms decrease. The properties of the bonded interactions for the octahedrally coordinated low-spin Fe atoms for pyrite and marcasite are distinct from those for high-spin Fe atoms for troilite, smythite, and greigite. The Fe-S bond lengths are shorter and the values of F(rc) and 32F(rc) are larger for pyrite and marcasite, indicating that the accumulation and local concentration of F(r) in the internuclear region are greater than those involving the longer, high-spin Fe-S bonded interactions. The net atomic charges and the bonded radii calculated for the Fe and S atoms in pyrite and marcasite are also smaller than those for sulfides with high-spin octahedrally coordinated Fe atoms. Collectively, the Fe-S interactions are indicated to be intermediate in character with the low-spin Fe-S interactions having greater shared character than the highspin interactions. The bond lengths observed for chalcopyrite together with the calculated bond critical point properties are consistent with the formula Cu+Fe3+S2. The bond length is shorter and the F(rc) value is larger for the FeS4 tetrahedron displayed by metastable greigite than those displayed by chalcopyrite and cubanite, consistent with a proposal that the Fe atom in greigite is tetravalent. S-S bond paths exist between each of the surface S atoms of adjacent slabs of FeS6 octahedra comprising the layer sulfide smythite, suggesting that the neutral Fe3S4 slabs are

  1. Chemical and sulphur isotope compositions of pyrite in the Jaduguda U (–Cu–Fe) deposit, Singhbhum shear zone, eastern India: Implications for sulphide mineralization

    Indian Academy of Sciences (India)

    Dipak C Pal; Surajit Sarkar; Biswajit Mishra; A K Sarangi

    2011-06-01

    The Jaduguda U (–Cu–Fe) deposit in the Singhbhum shear zone has been the most productive uranium deposit in India. Pyrite occurs as disseminated grains or in sulphide stringers and veins in the ore zone. Veins, both concordant and discordant to the pervasive foliation, are mineralogically either simple comprising pyrite ± chalcopyrite or complex comprising pyrite + chalcopyrite + pentlandite + millerite. Nickel-sulphide minerals, though fairly common in concordant veins, are very rare in the discordant veins. Pyrite in Ni-sulphide association is commonly replaced by pentlandite at the grain boundary or along micro-cracks. Based on concentrations of Co and Ni, pyrite is classified as: type-A — high Co (up to 30800 ppm), no/low Ni; type-B — moderate Co (up to 16500 ppm) and moderate to high Ni (up to 32700 ppm); type-C — no/low Co and high Ni (up to 43000 ppm); type-D — neither Co nor Ni. Textural and compositional data of pyrites suggest that the hydrothermal fluid responsible for pre-/early-shearing mineralization evolved from Co-rich to Ni-rich and the late-/post-shearing fluid was largely depleted in minor elements. Sulphur isotope compositions of pyrite mostly furnish positive values ranging between -0.33 and 12.06%. Composite samples of pyrites with only type-A compositions and mixed samples of type-A and type-B are consistently positive. However, pyrite with mixed type-A and type-C and pyrite with type-D compositions have negative values but close to 0. By integrating minor element and sulphur isotope compositions of pyrite in conjunction with other published data on the Jaduguda deposit, it is proposed that reduced sulphur for the precipitation of most pyrites (type-A, type-B) was likely derived from isotopically heavy modified seawater. However, some later sulphur might be magmatic in origin remobilized from existing sulphides in the mafic volcanic rocks in the shear zone.

  2. Copper indium disulfide nanocrystals supported on carbonized chicken eggshell membranes as efficient counter electrodes for dye-sensitized solar cells

    Science.gov (United States)

    Wang, Lidan; He, Jianxin; Zhou, Mengjuan; Zhao, Shuyuan; Wang, Qian; Ding, Bin

    2016-05-01

    A domestic waste, chicken eggshell membrane (ESM), is used as a raw material to fabricate carbonized ESM loaded with chalcopyrite CuInS2 nanocrystals (denoted CESM-CuInS2) by a simple liquid impregnation and carbonization method. The CESM-CuInS2 composite possesses a natural three-dimensional macroporous network structure in which numerous CuInS2 nanocrystals with a size of about 25 nm are inlaid in carbon submicron fibers that form a microporous network. The CESM-CuInS2 composite is used as the counter electrode in a dye-sensitized solar cell (DSSC) and its photoelectric performance is tested. The DSSC with a CESM-CuInS2 counter electrode exhibits a short-circuit current density of 12.48 mA cm-2, open-circuit voltage of 0.78 V and power conversion efficiency of 5.8%; better than the corresponding values for a DSSC with a CESM counter electrode, and comparable to that of a reference DSSC with a platinum counter electrode. The favorable photoelectric performance of the CESM-CuInS2 counter electrode is attributed to its hierarchical structure, which provides a large specific surface area and numerous catalytically active sites to facilitate the oxidation of the electrolyte. This new composite material has many advantages, such as low cost and simple preparation, compared with Pt and pure CuInS2 counter electrodes.

  3. Valence band offsets at Cu(In,Ga)Se{sub 2}/Zn(O,S) interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Adler, Tobias; Klein, Andreas [Surface Science Division, Institute of Materials Science, Technische Universitaet Darmstadt, Petersenstrasse 32, 64287, Darmstadt (Germany); Botros, Miriam [Surface Science Division, Institute of Materials Science, Technische Universitaet Darmstadt, Petersenstrasse 32, 64287, Darmstadt (Germany); Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Industriestrasse 6, 70565, Stuttgart (Germany); Witte, Wolfram; Hariskos, Dimitrios; Menner, Richard; Powalla, Michael [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Industriestrasse 6, 70565, Stuttgart (Germany)

    2014-09-15

    The energy band alignment at interfaces between Cu-chalcopyrites and Zn(O,S) buffer layers, which are important for thin-film solar cells, are considered. Valence band offsets derived from X-ray photoelectron spectroscopy for Cu(In,Ga)Se{sub 2} absorber layers with CdS and Zn(O,S) compounds are compared to theoretical predictions. It is shown that the valence band offsets at Cu(In,Ga)Se{sub 2}/Zn(O,S) interfaces approximately follow the theoretical prediction and vary significantly from sample to sample. The integral sulfide content of chemical bath deposited Zn(O,S) is reproducibly found to be 50-70%, fortuitously resulting in a conduction band offset suitable for solar cell applications with Cu(In,Ga)Se{sub 2} absorber materials. The observed variation in offset can neither be explained by variation of the Cu content in the Cu(In,Ga)Se{sub 2} near the interface nor by local variation of the chemical composition. Fermi level pinning induced by high defect concentrations is a possible origin of the variation of band offset. (copyright 2014 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  4. Zn incorporation and (CuIn)1-xZn2xSe2 thin film formation during the selenization of evaporated Cu and In precursors on Al:ZnO coated glass substrates

    Science.gov (United States)

    Guillén, C.; Herrero, J.

    2011-11-01

    CuInSe2 thin films with typical 1.0 eV gap energy and tetragonal chalcopyrite structure have been obtained on soda-lime glass substrates by the reaction of sequentially evaporated Cu and In layers with elemental selenium vapor, at 500 °C in flowing Ar. When analogous deposition and reaction processes were performed on Al:ZnO coated glasses, some increment in the band gap energy and diminution in the crystalline interplanar spacings have been detected for the resulting films with an extent that depends on the Cu/In atomic ratio of the evaporated precursor layers. This fact has been related to Zn incorporation into the selenized film, with quaternary (CuIn)1-xZn2xSe2 compound formation that is influenced by the presence of copper selenide phases during the reaction process. Such deductions are supported by the optical, structural and compositional characterizations that have been performed comparatively on samples prepared by selenization of evaporated metallic precursors with two different Cu/In ratios (0.9 and 1.1) on bare and Al:ZnO coated glass substrates.

  5. Comparison of photovoltaic parameters of Cu(In,Ga)Se2 thin film solar cells with infrared Images obtained with lock-in thermography

    Energy Technology Data Exchange (ETDEWEB)

    Klinkert, Torben; Ohland, Joerg; Knecht, Robin; Parisi, Juergen [Thin Film Photovoltaics, Energy- and Semiconductor Research Laboratory, University of Oldenburg, D-26111 Oldenburg (Germany); Schaeffler, Raymund; Dimmler, Bernhard [Wuerth Solar GmbH and Co. KG, Alfred-Leikam-Strasse 25, D-74523 Schwaebisch-Hall (Germany)

    2011-07-01

    The performance of photovoltaic modules comprised of monolithically series connected solar cells is basically determined by the weakest element in the circuit. In chalcopyrite thin film modules lateral film inhomogeneities and losses due to interconnection are likely to deteriorate the photovoltaic performance of individual cell stripes and, in consequence, to reduce the module efficiency. In this work we correlate microscopic features with the macroscopic device parameters of Cu(In,Ga)Se{sub 2} solar cells cut from large-area modules. Imaging of the film imperfections and regions of enhanced joule heating was realized by applying infrared Lock-In Thermography (LIT) with optical (I-LIT) and electrical (D-LIT) excitation of the sample. Via comparison of the infrared LIT images with the photovoltaic cell parameters obtained from STC current voltage profiling and quantum efficiency measurements we try to correlate macroscopic junction failure with microscopic disruptions of the film properties. These problems will also be discussed on the module level by analysis of D-LIT results obtained for individual cell stripes in an integrated series compound of a CIGSe-module.

  6. Investigation of defects in Cu(In,Ga)S{sub 2} and Cu(In,Ga)Se{sub 2} solar cells by space charge spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Riediger, Julia; Ohland, Joerg; Knipper, Martin; Parisi, Juergen; Riedel, Ingo [Thin Film Photovoltaics, Energy- and Semiconductor Research Laboratory, University of Oldenburg, D-26111 Oldenburg (Germany); Meeder, Alexander [Soltecture GmbH, 12487 Berlin (Germany)

    2012-07-01

    If deep defect states in the absorber of a solar cell act as recombination centers, they may limit the carrier lifetime and thus the open circuit voltage. This is related to the defect's activation energy and spatial position. In this study the defect landscape of chalcopyrite thin film solar cells with varied absorber composition was investigated by space charge spectroscopy. The absorber layer in Cu(In,Ga)S{sub 2} samples arises from rapid thermal process (RTP) in sulfur vapor while Cu(In,Ga)Se{sub 2} absorbers were processed via co-evaporation of the constituents. Several defect states were found by deep level spectroscopy (DLTS) and thermal admittance spectroscopy (TAS). With the knowledge of the defect activation energies we derived the spatial defect concentrations from (illuminated) capacitance-voltage (CV) measurements and discuss the results for both material systems. To identify the often discussed ''N1'' defect, the measurements were repeated after annealing and changes in the defect spectra were evaluated.

  7. Identification of defects and metastabilities in Cu(In,Ga)Se{sub 2} thin film solar cells; Identifikation von Defekten und Metastabilitaeten in Cu(In,Ga)Se{sub 2}-Duennschichtsolarzellen

    Energy Technology Data Exchange (ETDEWEB)

    Eisenbarth, Tobias

    2010-05-10

    Chapter 2 introduces the Cu(In,Ga)Se{sub 2} chalcopyrite material and describes its physical properties. Starting from the crystal system the influence of intrinsic defects is discussed. In chapter 3 foundations, which are necessary for the understanding of the functionality of the Cu(In,Ga)Se{sub 2} thin-film solar cells, are introduced. Starting from the description of the p/n homotransition the heterotransition is thematized. The fabrication of the thin-film solar cell is explained, and the electrical quantities for the general characterization of solar cells are introduced. Chapter 4 explains the applied analysis methods and is especially dedicated to the capacitative effect of the space-charge zone. Starting from the behaviour of the Cu(In,Ga)Se{sub 2} heterotransition in the ac modus the temperature-dependent current-voltage analysis in the dc operation is explained. Finally the measuring place constructed in the framework of this thesis is described. Chapter 5 is dedicated to the defect spectroscopy. In this chapter an analysis of the for Cu(In,Ga)Se{sub 2} solar cells typically observed phenomena is presented. Starting from a literature survey the results are evaluated in relation to existing models and a new model presented. In chapter 6 results from metastability studies are presented. The observed metastability phenomena are newly evaluated in the consequence of the results and interpretations from chapter 5. The results are put in relation with results and models from the literature and discussed.

  8. Composition and growth procedure-dependent properties of electrodeposited CuInSe 2 thin films

    Science.gov (United States)

    Babu, S. Moorthy; Ennaoui, A.; Lux-Steiner, M. Ch.

    2005-02-01

    CuInSe 2 thin films were deposited on molybdenum-coated glass substrates by electrodeposition. Deposition was carried out with a variety of electrochemical bath compositions. The quality of the deposits depends very much on the source materials as well as the concentration of the same in the electrolyte. The deposition potential was varied from -0.4 to -0.75 V vs. SCE. The pH of the solution was adjusted to 1.5-2 using diluted sulphuric acid. Chloride salts containing bath yield good surface morphology, but there is always excess of the metallic content in the deposited films. Different growth procedures, like initial metallic layers of copper or indium, layers of copper selenide or indium selenide before the actual deposition of ternary chalcopyrite layers were attempted. Fabrication pathway, morphological and compositional changes due to the different precursor route has been analysed. The quality of the deposits prepared by one-step electrodeposition is better than the deposits with a two-stage process. The deposited films were characterized with XRD, SEM-EDAX, UV-visible spectroscopy and I- V characteristics. The deposited films were annealed in air as well as in nitrogen atmosphere. The influence of annealing temperature, environment and annealing time on the properties of the films are evaluated. Attempts were made to fabricate solar cell structure from the deposited absorber films. The structure of Mo/CuInSe 2/CdS/ZnO/Ni was characterized with surface, optical and electrical studies.

  9. Variation of sulfur content in Cu(In,Ga)(S,Se){sub 2} thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Knipper, Martin; Knecht, Robin; Riedel, Ingo; Parisi, Juergen [Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg (Germany)

    2011-07-01

    Chalcopyrite thin film solar cells made of the compound semiconductor Cu(In,Ga)(S,Se){sub 2} (CIGSSe) have a strong potential for achieving high efficiencies at low production costs. Volume production of CIGSSe-modules has already started to exploit their favorable attributes such as low cost processing and reasonable module efficiency. In this study we studied industrially produced CIGSSe modules obtained from rapid thermal processing (RTP) for sulfurization. In detail, we investigated the effect of sulfur offer and RTP temperature (500 C to 580 C) on the photoelectric characteristics of small-area solar cells cut from the modules. Current-voltage profiling under standard test conditions revealed a strong influence of the particular process recipe on the open circuit voltage whereas significant variations of the maximum quantum efficiency can be observed. X-ray diffraction was employed to relate these effects to the crystallographic structure of the actual CIGSSe films. Lock-in thermographic imaging was employed to link apparent film inhomogeneities and disruptions to the specific process recipe.

  10. Investigations on electron beam evaporated Cu(In{sub 0.85}Ga{sub 0.15})Se{sub 2} thin film solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Venkatachalam, M.; Kannan, M.D.; Prasanna, S.; Jayakumar, S.; Balasundaraprabhu, R. [Thin Film Center, Department of Physics, PSG College of Technology, Coimbatore (India); Muthukumarasamy, N. [Department of Physics, Coimbatore Institute of Technology, Coimbatore (India); Saroja, M. [Department of Electronics, Erode Arts College, Erode (India)

    2009-09-15

    CIGS bulk with composition of CuIn{sub 0.85}Ga{sub 0.15}Se{sub 2} was synthesized by direct reaction of elemental copper, indium, gallium and selenium. CIGS thin films were then deposited onto well-cleaned glass substrates using the prepared bulk alloy by electron beam deposition method. The structural properties of the deposited films were studied using X-ray diffraction technique. The as-deposited CIGS films were found to be amorphous. On annealing, the films crystallized with a tetragonal chalcopyrite structure. An intermediate Cu-rich phase precipitated at 200 C and dissociated at higher annealing temperatures. Average grain size calculated from the XRD spectra indicated that the films had a nano-crystalline structure and was further corroborated by AFM analysis of the sample surface. The chemical constituents present in the deposited CIGS films were identified using energy dispersive X-ray analysis. CIGS based solar cells were then fabricated on molybdenum and ITO coated glass substrates and the efficiencies have been evaluated. (author)

  11. Band alignment at sputtered ZnS{sub x} O{sub 1-x}/Cu(In,Ga)(Se,S){sub 2} heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Kieven, D.; Grimm, A.; Lauermann, I.; Lux-Steiner, M.C.; Klenk, R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie, Berlin (Germany); Palm, J.; Niesen, T. [AVANCIS GmbH and Co. KG, Munich (Germany)

    2012-07-15

    Valence band offsets {delta}E{sub VBM} at ZnS{sub x} O{sub 1-x}/Cu(In,Ga)(Se,S){sub 2} (CIGSSe) heterojunctions have been studied by photoemission spectroscopy (XPS, UPS) as a function of composition x in sputtered ZnS{sub x} O{sub 1-x} films. In the composition range from ZnO to ZnS we found {delta}E{sub VBM} between -(2.1 {+-} 0.3) eV and -(0.8 {+-} 0.4) eV, respectively. Considering the optical band gaps, the conduction band offsets {delta}E{sub CBM} range from -(0.1 {+-} 0.3) eV to +(1.4 {+-} 0.4) eV. These results suggest that sputtered ZnS{sub x} O{sub 1-x} is suitable as substitution for the CdS buffer and ZnO window layers in standard chalcopyrite-based solar cells. Current-voltage characteristics of the solar cells have been investigated as a function of the composition x. (copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  12. Optoelectronic properties of Cu(In,Ga)(S,Se){sub 2} thin film solar obtained from varied chalcogenization processes

    Energy Technology Data Exchange (ETDEWEB)

    Knecht, Robin; Knipper, Martin; Riedel, Ingo; Parisi, Juergen [Energy and Semiconductor Research Laboratory, Department of Physics, University of Oldenburg (Germany)

    2010-07-01

    Thin film solar cells made of the chalcopyrite compound semiconductor Cu(In,Ga)(S,Se){sub 2} (CIGSSe) exhibit strong potential for achieving high efficiency at relatively low production costs. While large scale production of CIGSSe-modules has been launched in different companies the transfer of high laboratory cell efficiencies to the module scale is still a major challenge. In order to improve module efficiencies optimisation of the large scale production process presents a major issue. In this work the influence of chalcogenization (selenisation and sulfurisation) parameter variation on the device characteristics was studied using temperature and illumination dependent current-voltage profiling, external quantum efficiency measurements as well as temperature dependent capacitance-voltage measurements. From these measurements we derived important characteristics of the light absorber like activation energy of the recombination current, estimation of the absorber band gap as well as the doping concentration along with the diffusion potential. These studies were completed by defect spectroscopy for analysis of defect formation in the absorber material. The results obtained from these investigations are compared for samples exposed to different conditions of the chalcogenization process.

  13. Characterisation of CuInSe2-based solar cells with different buffer layers

    Energy Technology Data Exchange (ETDEWEB)

    Werth, Anton; Ohland, Joerg; Riedel, Ingo; Parisi, Juergen [Abteilung EHF, Institiut fuer Physik, Carl von Ossietzky Universitaet, Oldenburg (Germany); Rechid, Juan [CIS Solartechnik GmbH and Co. KG, c/o Aurubis AG, Hamburg (Germany)

    2010-07-01

    The optoelectronic properties of the buffer layer in chalcopyrite solar cells may present strong efficiency limitation due to parasitic absorption, interface states and band discontinuities in respect of the light absorber. In this work we investigated CuInSe{sub 2}-based (CIS) solar cells processed on flexible steel substrates with In{sub 2}S{sub 3} and CdS buffer layers by means of temperature dependent current-voltage (J-V) measurements at varying illumination intensity and external quantum efficiency (EQE) measurements. Under illumination the J-V curves of both cell types exhibit distinct ''s''-shape non-ideality (roll over) at temperatures below 260 K. The occurrence of the ''s''-shape in the 4th and/or 1st quadrant is explained by an heuristic model which relates the band discontinuity being present at the buffer CIS interface to limitation of the minority carrier extraction and injection. Further, we employed the suns-V{sub oc} method to extract the diode parameters saturation current and diode ideality from the J-V characteristics under illumination (small effect of series resistance) in order to identify clues on dominant surface or bulk recombination. We conclude that interface recombination is less dominant in the investigated samples independent of the used buffer material.

  14. Temperature dependence of band gaps in semiconductors: electron-phonon interaction

    Energy Technology Data Exchange (ETDEWEB)

    Kremer, Reinhard K.; Cardona, M.; Lauck, R. [MPI for Solid State Research, Stuttgart (Germany); Bhosale, J.; Ramdas, A.K. [Physics Dept., Purdue University, West Lafayette, IN (United States); Burger, A. [Fisk University, Dept. of Life and Physical Sciences, Nashville, TN (United States); Munoz, A. [MALTA Consolider Team, Dept. de Fisica Fundamental II, Universidad de La Laguna, Tenerife (Spain); Instituto de Materiales y Nanotecnologia, Universidad de La Laguna, Tenerife (Spain); Romero, A.H. [CINVESTAV, Dept. de Materiales, Unidad Queretaro, Mexico (Mexico); MPI fuer Mikrostrukturphysik, Halle an der Saale (Germany)

    2013-07-01

    We investigate the temperature dependence of the energy gap of several semiconductors with chalcopyrite structure and re-examine literature data and analyze own high-resolution reflectivity spectra in view of our new ab initio calculations of their phonon properties. This analysis leads us to distinguish between materials with d-electrons in the valence band (e.g. CuGaS{sub 2}, AgGaS{sub 2}) and those without d-electrons (e.g. ZnSnAs{sub 2}). The former exhibit a rather peculiar non-monotonic temperature dependence of the energy gap which, so far, has resisted cogent theoretical description. We demonstrate it can well be fitted by including two Bose-Einstein oscillators with weights of opposite sign leading to an increase at low-T and a decrease at higher T's. We find that the energy of the former correlates well with characteristic peaks in the phonon density of states associated with low-energy vibrations of the d-electron constituents.

  15. Regional tectonics, geology, magma chamber processes and mineralisation of the Jinchuan nickel-copper-PGE deposit, Gansu Province, China: A review

    Directory of Open Access Journals (Sweden)

    T.M. (Mike Porter

    2016-05-01

    The Jinchuan ultramafic intrusion was injected into three interconnected sub-chambers, each containing a separate orebody. It essentially comprises an olivine-orthopyroxene-chromite cumulate, with interstitial orthopyroxene, clinopyroxene, plagioclase and phlogopite, and is predominantly composed of lherzolite (∼80%, with an outer rim of olivine pyroxenite and cores of mineralised dunite. Mineralisation occurs as disseminated and net-textured sulphides, predominantly within the dunite, with lesser, PGE rich lenses, late massive sulphide accumulations, small copper rich pods and limited mineralised diopside skarn in wall rock marbles. The principal ore minerals are pyrrhotite (the dominant sulphide, pentlandite, chalcopyrite, cubanite, mackinawite and pyrite, with a variety of platinum group minerals and minor gold. The deposit underwent significant post-magmatic tremolite-actinolite, chlorite, serpentine and magnetite alteration. The volume of the Jinchuan intrusion accounts for <3% of the total parental magma required to generate the contained olivine and sulphide. It is postulated that mafic melt, intruded into the lower crust, hydraulically supported by density contrast buoyancy from below the Moho, ponded in a large staging chamber, where crystallisation and settling formed a lower sulphide rich mush. This mush was subsequently injected into nearby shallow dipping faults to form the Jinchuan intrusion.

  16. Aplicação de técnicas eletroquímicas no estudo da dissolução oxidativa da covelita (CuS por Thiobacillus ferrooxidans Electrochemical techniques applied to study the oxidative dissolution of the covellite: CuS by Thiobacillus ferrooxidans

    Directory of Open Access Journals (Sweden)

    Christiane Medina Teixeira

    2002-02-01

    Full Text Available Among the copper sulphides, chalcopyrite (CuFeS2, covellite (CuS and chalcocite (Cu2S are the most important source of minerals for copper mining industry. The acknowledge of behaviour of these sulphides related with bacterial leaching process are essential for optimization procedures. Despite of its importance, covellite has not deserved much interest of researchers regarding this matter. In this work it was studied the oxidation of covellite by the chemolithotrophic bacterium Thiobacillus ferrooxidans by using electrochemical techniques, such as open circuit potentials with the time and cyclic voltammetry. The experiments were carried out in acid medium (pH 1.8, containing or not Fe2+ as additional energy source, and in different periods of incubation; chemical controls were run in parallel. The results showed that a sulphur layer is formed spontaneously due the acid attack, covering the sulphide in the initial phase of incubation, blocking the sulphide oxidation. However, the bacterium was capable to oxidize this sulphur layer. In the presence of Fe2+ as supplemental energy source, the corrosion process was facilitated, because ocurred an indirect oxidation of covellite by Fe3+, which was produced by T. ferrooxidans oxidation of the Fe2+ added in the medium.

  17. Thermal Decomposition Based Synthesis of Ag-In-S/ZnS Quantum Dots and Their Chlorotoxin-Modified Micelles for Brain Tumor Cell Targeting.

    Science.gov (United States)

    Chen, Siqi; Ahmadiantehrani, Mojtaba; Publicover, Nelson G; Hunter, Kenneth W; Zhu, Xiaoshan

    Cadmium-free silver-indium-sulfide (Ag-In-S or AIS) chalcopyrite quantum dots (QDs) as well as their core-shell structures (AIS/ZnS QDs) are being paid significant attention in biomedical applications because of their low toxicity and excellent optical properties. Here we report a simple and safe synthetic system to prepare high quality AIS and AIS/ZnS QDs using thermal decomposition. The synthetic system simply involves heating a mixture of silver acetate, indium acetate, and oleic acid in dodecanethiol at 170 °C to produce AIS QDs with a 13% quantum yield (QY). After ZnS shell growth, the produced AIS/ZnS QDs achieve a 41% QY. To facilitate phase transfer and bioconjugation of AIS/ZnS QDs for cellular imaging, these QDs were loaded into the core of PLGA-PEG (5k:5k) based micelles to form AIS/ZnS QD-micelles. Cellular imaging studies showed that chlorotoxin-conjugated QD-micelles can be specifically internalized into U-87 brain tumor cells. This work discloses that the scalable synthesis of AIS/ZnS QDs and the facile surface/interface chemistry for phase transfer and bioconjugation of these QDs may open an avenue for the produced QD-micelles to be applied to the detection of endogenous targets expressed on brain tumor cells, or more broadly to cell- or tissue-based diagnosis and therapy.

  18. Acid rock drainage formation and treatment: a review

    Energy Technology Data Exchange (ETDEWEB)

    Nosa O. Egiebor; Ben Oni [Tuskegee University, Tuskegee, AL (United States). Environmental Engineering Program

    2007-05-15

    The exploitation of coal and metallic mineral resources worldwide normally results in the production of large quantities of overburden, gangue, and tailings materials containing significant amounts of sulfide minerals. These sulfide minerals, which include sphalerite, chalcopyrite, galena, and other complex sulfides, are often disseminated in pyrite, which is the most abundant sulfide mineral in the earth's crust. Once exposed to water and oxygen through mining and mineral processing operations, these sulfides become immediately susceptible to chemical and biochemical oxidation with the consequent production of highly acidic, metal-laden leachates, which are generally referred to as acid rock drainage (ARD) or acid mine drainage (AMD). This ARD production, which can be sustained for hundreds of years, has become the single biggest environmental problem facing the mining and mineral industry. Untreated acid rock drainage leads to serious contamination of large areas of land, as well as surface and ground water resources. The seriousness of the problem has led to major research efforts to find solutions. However, effective ARD treatment and prevention solutions have eluded the scientific community over the past decades. This paper presents a detailed review of the current state of scientific knowledge with regard to the magnitude of the problem, the chemistry and mechanism of sulfide mineral oxidation and ARD formation, the role of microorganisms in ARD formation process, and the proposed approaches for the treatment, control, and prevention of ARD formation.

  19. Geochemical Characteristics of Jinwozi Gold Deposit,Xinjiang

    Institute of Scientific and Technical Information of China (English)

    章振根; 陈南生

    1991-01-01

    The Jinwozi gold deposit consists of gold-bearing quartz veins in a biotite granodiorite of Hercynian age (Zircon U-Pb age≈335.7Ma).Ore mineralogy is simple .In addition to native gold,there are only small amounts of sulfides,meinly pyrite and minor sphalerite,chalcopyrite and galena.δ34S val-ues average 6.69‰,and δ18O13.99‰.Abundant CO2 is contained in fluid inclusions from quartz.Homogenization temperatures of fluid inclusions are between 186 and 262°.REE distribution pat-terns indicate that the igneous mass may have been derived from a common initial material of calcareous-argillaceous sediments and alkali basalts as the country rocks.In other words,the Jinwozi granodiorite is of remelting origin from crustal material.Isotopic evidence of S,O and Pb shows that the ore-forming material is genetically related to magmatic hydrothermal activity.

  20. Form of Occurrence and Distribution Law of Associated Gold(Silver)in Anhui Tongling Huashupo Copper Mine%安徽铜陵桦树坡铜矿床伴生金(银)赋存状态及分布规律

    Institute of Scientific and Technical Information of China (English)

    陈耀远; 周贵斌

    2012-01-01

    Huashupo copper ore deposit is controlled skam-type. By thin section authentication and electron probe microanalyais, the ore deposit's mineral species are not much, trace mineral species are much. They are mainly chalcopyrite, pyrrhotite, pyrite, and gold and silver, native bismuth. The study of process mineralogy is made, and finds out the form of occurrence and process nature, providing reference for reasonably determining preparing process and conditions.%桦树坡铜矿床为一层控式矽卡岩型铜矿床,经光薄片鉴定及电子探针分析,该矿床主要矿物种类不多,而微量矿物种类较多,主要矿物有为黄铜矿、磁黄铁矿、黄铁矿,自然元素为金—银系列矿物及自然铋等.对该铜矿进行了工艺矿物学研究,重点查明了伴生金银的赋存状态及工艺性质.为伴生金银回收确定合理选矿工艺流程及条件提供依据.

  1. Semi-transparent solar cells

    Science.gov (United States)

    Sun, J.; Jasieniak, J. J.

    2017-03-01

    Semi-transparent solar cells are a type of technology that combines the benefits of visible light transparency and light-to-electricity conversion. One of the biggest opportunities for such technologies is in their integration as windows and skylights within energy-sustainable buildings. Currently, such building integrated photovoltaics (BIPV) are dominated by crystalline silicon based modules; however, the opaque nature of silicon creates a unique opportunity for the adoption of emerging photovoltaic candidates that can be made truly semi-transparent. These include: amorphous silicon-, kesterite-, chalcopyrite-, CdTe-, dye-sensitized-, organic- and perovskite- based systems. For the most part, amorphous silicon has been the workhorse in the semi-transparent solar cell field owing to its established, low-temperature fabrication processes. Excitement around alternative classes, particularly perovskites and the inorganic candidates, has recently arisen because of the major efficiency gains exhibited by these technologies. Importantly, each of these presents unique opportunities and challenges within the context of BIPV. This topic review provides an overview into the broader benefits of semi-transparent solar cells as building-integrated features, as well as providing the current development status into all of the major types of semi-transparent solar cells technologies.

  2. Electrical characterization of all-sputtered CdS/CuInSe sub 2 solar cell heterojunctions

    Energy Technology Data Exchange (ETDEWEB)

    Santamaria, J.; Martil, I.; Iborra, E.; Gonzalez Diaz, G.; Sanchez Quesada, F. (Dept. Electricidad y Electronica, Univ. Complutense, Madrid (Spain))

    1990-01-01

    Current-voltage (J-V) and capacitance-frequency (C-F) measurements were taken for all-sputtered CdS/CuInSe{sub 2} solar cell heterojunctions, in the range 100 Hz - 10 MHz, to investigate the effect of interface states on the conduction mechanism. The samples analyzed had different compositions for the chalcopyrite CuInSe{sub 2} layer. All of the samples showed a hybrid tunneling/interface recombination mechanism with the major contribution coming from the interface recombination mechanism for devices having a stoichiometric or indium-rich CuInSe{sub 2} layer, and from the tunneling conduction mechanism for copper-rich devices. An estimation of the relative distribution of interface states has been performed. The values obtained for interface state density were as high as 6x10{sup 12} V{sup -1} cm{sup -2} for copper-rich heterojunctions, and were lower than 2x10{sup 11} V{sup -1} cm{sup -2} for devices having a stoichiometric or indium-rich CuInSe{sub 2} layer. (orig.).

  3. Isolation and identification of moderately thermophilic acidophilic iron-oxidizing bacterium and its bioleaching characterization

    Institute of Scientific and Technical Information of China (English)

    ZENG Wei-min; WU Chang-bin; ZHANG Ru-bing; HU Pei-lei; QIU Guan-zhou; GU Guo-hua; ZHOU Hong-bo

    2009-01-01

    A moderately thermophilic acidophilic iron-oxidizing bacterium ZW-1 was isolated from Dexing mine, Jiangxi Province, China. The morphological, biochemical and physiological characteristics, 16S rRNA sequence and bioleaching characterization of strain ZW-1 were studied. The optimum growth temperature is 48 ℃, and the optimum initial pH is 1.9. The strain can grow autotrophically by using ferrous iron or elemental sulfur as sole energy sources. The strain is also able to grow heterotrophically by using peptone and yeast extract powder, but not glucose. The cell density of strain ZW-1 can reach up to 1.02×108 /mL with addition of 0.4 g/L peptone. A phylogenetic tree was constructed by comparing with the published 16S rRNA sequences of the relative bacteria species. In the phylogenetic tree, strain ZW-1 is closely relative to Sulfobacilus acidophilus with more than 99% sequence similarity. The results of bioleaching experiments indicate that the strain could oxidize Fe2+ efficiently, and the maximum oxidizing rate is 0.295 g/(L·h). It could tolerate high concentration of Fe3+ and Cu2+ (35 g/L and 25 g/L, respectively). After 20 d, 44.6% of copper is extracted from chalcopyrite by using strain ZW-1 as inocula.

  4. Computational Nano-materials Design for Spinodal Nanotechnology as a New Class of Bottom-up Nanotechnology

    Science.gov (United States)

    Katayama-Yoshida, Hiroshi; Fukushima, Tetsuya; Sato, Kazunori

    Based on the spinodal nano-decomposition (SND) of dilute magnetic semiconductors (DMS), we generalized the SND to the application of catalysis and photovoltaic solar-cells, where nano-scale particle formation in catalysis and and nano-scale separation of electrons and holes are essential in order to enhance the efficiency. First, we summarize the shape control (Konbu- & Dairiseki-Phases) and dimensionality dependence of crystal growth condition on SND in DMS. Second, we discuss the application of SND for the formation of nano-particles and the self-regeneration in three-way catalysis for automotive emission control by Perovskite La(Fe,Pd or Rh)O3. Third, we propose (i) self-regeneration mechanism and (ii) self-organized nano-structures by SND in chalcopyrite Cu(In,Ga)Se2, Kesterite Cu2ZnSnSe4, and Perovskite CsSnI3 for the low-cost, environment-friendly and high-efficiency photovoltaic solar cells using first-principles calculations.

  5. Synthesis of CuInS2 thin films by spray pyrolysis deposition system

    Science.gov (United States)

    Hussain, K. M. A.; Podder, J.; Saha, D. K.

    2013-02-01

    Copper indium disulfide (CuInS2) thin films were deposited on the glass substrate by the locally made spray pyrolysis deposition system. The films were characterized by using energy dispersive analytical X-ray (EDAX) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction (XRD) and UV-VIS-NIR spectrophotometry. The XRD pattern indicated that the prepared CuInS2 thin films are chalcopyrite structure. Lattice parameters and FWHM values were verified by the standard values of JCPDS 270159 file. The EDAX analysis indicated the stoichiometric ratio of 1.14:1:1.88 (CIS-2) thin films. The SEM analysis showed that the average grain size of the film was 100-800 nm and that of XRD data indicate the values of 30-50 nm. The high absorption co-efficient and 1.48 eV band gap of the films indicate that the films are useful as an absorber for photovoltaic application in the solar cell.

  6. Formation of CuInGaSe2 thin film photovoltaic absorber by using rapid thermal sintering of binary nanoparticle precursors

    Science.gov (United States)

    Liu, Chung Ping; Chang, Ming Wei; Chuang, Chuan Lung

    2013-12-01

    It was known that properties of copper-indium-gallium-diselenide (CIGS) thin films were evidently affected by precursor nanoparticle-ink and sintering technology. The nanoparticles were fabricated by using a rotary ball-milling (RBM) technique. After RBM, the particle size of the agglomerated CIGS powder was smaller than 100 nm. The nanoparticle ink was printed onto a Mo/soda lime glass substrate and baked at a low temperature to remove solvents and to form a dry precursor. Crystallographic, morphological, and stoichiometric properties of films were then obtained by using the precursor CIGS samples sintered at various heating rates in a non-vacuum environment without selenization. Analytical results revealed that the 2-theta data of the sample sintered at a heating rate of 15 °C/s were the closest to the data on the JCPDS card for Cu(Ga0.3In0.7)Se2.0 because their angles were 26.8°, 44.5°, and 52.7°, respectively. In addition, analytical results indicated that the CIGS absorption layer prepared at a heating rate of 15 °C/s had a chalcopyrite structure and favorable compositions. For this sample, the mole ratio of Cu:In:Ga:Se was equal to 0.98:0.81:0.28:1.93, and related ratios of Ga/(In+Ga) and Cu/(In+Ga) were 0.26 and 0.90, respectively.

  7. Observation of core-level binding energy shifts between (100) surface and bulk atoms of epitaxial CuInSe{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, A.J. [Colorado School of Mines, Golden, CO (United States); Berry, G.; Rockett, A. [Univ. of Illinois, Urbana-Champaign, IL (United States)] [and others

    1997-04-01

    Core-level and valence band photoemission from semiconductors has been shown to exhibit binding energy differences between surface atoms and bulk atoms, thus allowing one to unambiguously distinguish between the two atomic positions. Quite clearly, surface atoms experience a potential different from the bulk due to the lower coordination number - a characteristic feature of any surface is the incomplete atomic coordination. Theoretical accounts of this phenomena are well documented in the literature for III-V and II-VI semiconductors. However, surface state energies corresponding to the equilibrium geometry of (100) and (111) surfaces of Cu-based ternary chalcopyrite semiconductors have not been calculated or experimental determined. These compounds are generating great interest for optoelectronic and photovoltaic applications, and are an isoelectronic analog of the II-VI binary compound semiconductors. Surface core-level binding energy shifts depend on the surface cohesive energies, and surface cohesive energies are related to surface structure. For ternary compound semiconductor surfaces, such as CuInSe{sub 2}, one has the possibility of variations in surface stoichiometry. Applying standard thermodynamical calculations which consider the number of individual surface atoms and their respective chemical potentials should allow one to qualitatively determine the magnitude of surface core-level shifts and, consequently, surface state energies.

  8. Fabrication of a Cu(InGaSe2 Thin Film Photovoltaic Absorber by Rapid Thermal Annealing of CuGa/In Precursors Coated with a Se Layer

    Directory of Open Access Journals (Sweden)

    Chun-Yao Hsu

    2013-01-01

    Full Text Available Cu(InGaSe2 (CIGS thin film absorbers are prepared using sputtering and selenization processes. The CuGa/In precursors are selenized during rapid thermal annealing (RTA, by the deposition of a Se layer on them. This work investigates the effect of the Cu content in precursors on the structural and electrical properties of the absorber. Using X-ray diffraction, field emission scanning electron microscopy, Raman spectroscopy, and Hall effect measurement, it is found that the CIGS thin films produced exhibit facetted grains and a single chalcopyrite phase with a preferred orientation along the (1 1 2 plane. A Cu-poor precursor with a Cu/( ratio of 0.75 demonstrates a higher resistance, due to an increase in the grain boundary scattering and a reduced carrier lifetime. A Cu-rich precursor with a Cu/( ratio of 1.15 exhibits an inappropriate second phase ( in the absorber. However, the precursor with a Cu/( ratio of 0.95 exhibits larger grains and lower resistance, which is suitable for its application to solar cells. The deposition of this precursor on Mo-coated soda lime glass substrate and further RTA causes the formation of a MoSe2 layer at the interface of the Mo and CIGS.

  9. Investigation of defect properties in Cu(In,Ga)Se 2 solar cells by deep-level transient spectroscopy

    Science.gov (United States)

    Kerr, L. L.; Li, Sheng S.; Johnston, S. W.; Anderson, T. J.; Crisalle, O. D.; Kim, W. K.; Abushama, J.; Noufi, R. N.

    2004-09-01

    The performance of the chalcopyrite material Cu(In,Ga)Se 2 (CIGS) used as an absorber layer in thin-film photovoltaic devices is significantly affected by the presence of native defects. The deep-level transient spectroscopy (DLTS) technique is used in this work to characterize the defect properties, yielding relevant information about the defect types, their capture cross-sections, and energy levels and densities in the CIGS cells. Three solar cells developed using different absorber growth technologies were analyzed using DLTS, capacitance-voltage ( C- V), and capacitance-temperature ( C- T) techniques. It was found that CIS cells grown at the University of Florida exhibits a middle-gap defect level that may relate to the cell's low fill factor and open-circuit voltage values observed. A high efficiency ( ηc>18%) CIGS cell produced by the National Renewable Energy Laboratory (NREL) was found to contain three minority-carrier (electron) traps and a 13% CIGS cell produced by the Energy Photovoltaics Inc. (EPV) exhibited one majority (hole) trap. The approach followed using the DLTS technique serves as a paradigm for revealing the presence of significant defect levels in absorber materials, and may be used to support the identification of remedial processing operations.

  10. Influence of Ce doping on structural and photoelectric properties of CuInS2 thin films

    Science.gov (United States)

    Zhu, Jun; Xiao, Lingling; Ding, Tiezhu; Wang, Yanlai; Fan, Yue

    2015-09-01

    Cerium doped CuInS2 thin films were successfully fabricated by a powder metallurgy method. X-ray diffraction and scanning electron microscope measurements showed that the as-prepared CuIn1-xCexS2 samples are of good crystallinity and crystallize with chalcopyrite structure when sintering at 550 °C. The presence of Ce3+ in host material was conformed by X-ray photoelectron spectroscopy. Two subband photon absorption peaks were observed at 1710 nm (0.73 eV) and 1955 nm (0.63 eV) in the UV-Vis-NIR absorption spectrum. This behavior could suggest that an intermediate band forms in the forbidden band of CuInS2 semiconductor due to cerium incorporation. The optical bandgap of CuIn1-xCexS2 films was tuned in the range of 1.38 eV to 1.23 eV with increasing cerium content. And the electrical conductivity could be improved if doped moderate cerium content, especially x = 0.1.

  11. Influence of Ce doping on structural and photoelectric properties of CuInS{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jun, E-mail: jiulye@126.com; Xiao, Lingling; Ding, Tiezhu; Wang, Yanlai; Fan, Yue [School of Physical Science and Technology, Inner Mongolia University, Key Laboratory of Semiconductor Photovoltaic Technology at Universities of Inner Mongolia Autonomous Region, Hohhot 010021 (China)

    2015-09-21

    Cerium doped CuInS{sub 2} thin films were successfully fabricated by a powder metallurgy method. X-ray diffraction and scanning electron microscope measurements showed that the as-prepared CuIn{sub 1−x}Ce{sub x}S{sub 2} samples are of good crystallinity and crystallize with chalcopyrite structure when sintering at 550 °C. The presence of Ce{sup 3+} in host material was conformed by X-ray photoelectron spectroscopy. Two subband photon absorption peaks were observed at 1710 nm (0.73 eV) and 1955 nm (0.63 eV) in the UV–Vis–NIR absorption spectrum. This behavior could suggest that an intermediate band forms in the forbidden band of CuInS{sub 2} semiconductor due to cerium incorporation. The optical bandgap of CuIn{sub 1−x}Ce{sub x}S{sub 2} films was tuned in the range of 1.38 eV to 1.23 eV with increasing cerium content. And the electrical conductivity could be improved if doped moderate cerium content, especially x = 0.1.

  12. The nature and genesis of marginal Cu-PGE-Au sulphide mineralisation in Paleogene Macrodykes of the Kangerlussuaq region, East Greenland

    Science.gov (United States)

    Holwell, David A.; Abraham-James, Thomas; Keays, Reid R.; Boyce, Adrian J.

    2012-01-01

    The Kangerlussuaq region of East Greenland hosts a variety of early Tertiary extrusive and intrusive igneous rocks related to continental break up and the passage of the ancestral Iceland plume. These intrusive bodies include a number of gabbroic macrodykes, two of which—the Miki Fjord Macrodyke, and the newly discovered Togeda Macrodyke—contain Cu-PGE-Au sulphide mineralisation along their margins. Sulphides occur as disseminated interstitial blebs and rounded globules of chalcopyrite and pyrrhotite with some Fe-Ti oxides and platinum-group minerals, comprising largely Pd bismuthides and tellurides. The globules are interpreted to have formed from fractionation of trapped droplets of an immiscible Cu- and Pd-rich sulphide melt and show geopetal indicators. Sulphur isotopes imply a local crustal source of S in these from pyritic sediments of the Kangerlussuaq Basin. Thus, generation of these sulphide occurrences was controlled by local country rock type. Low Ni/Cu and Pt/Pd ratios, also present in the Platinova reefs in the Skaergaard Intrusion, indicate that early fractionation of olivine may have depleted the magma of Ni and suggest the likely presence of a large magma chamber at depth. Xenoliths of Ni-rich olivine cumulates in the Miki Fjord Macrodyke may have been sourced from such a body. The location of thus far unidentified conduit or feeder zones to the macrodykes beneath the present day surface may represent potential targets for more massive sulphide orebodies.

  13. Development of novel control system to grow ZnO thin films by reactive evaporation

    Directory of Open Access Journals (Sweden)

    Gerardo Gordillo

    2016-07-01

    Full Text Available This work describes a novel system implemented to grow ZnO thin films by plasma assisted reactive evaporation with adequate properties to be used in the fabrication of photovoltaic devices with different architectures. The innovative aspect includes both an improved design of the reactor used to activate the chemical reaction that leads to the formation of the ZnO compound as an electronic system developed using the virtual instrumentation concept. ZnO thin films with excellent opto-electrical properties were prepared in a reproducible way, controlling the deposition system through a virtual instrument (VI with facilities to control the amount of evaporated zinc involved in the process that gives rise to the formation of ZnO, by means of the incorporation of PID (proportional integral differential and PWM (pulse width modulation control algorithms. The effectiveness and reliability of the developed system was verified by obtaining with good reproducibility thin films of n+-ZnO and i-ZnO grown sequentially in situ with thicknesses and resistivities suitable for use as window layers in chalcopyrite based thin film solar cells.

  14. 电沉积-退火工艺制备铜铟硒太阳能电池薄膜及表征%Preparation and Characterization of Electrodeposited-Annealed CulnSe2 Thin Films for Solar Cells

    Institute of Scientific and Technical Information of China (English)

    张中伟; 郭宏艳; 李纪; 朱长飞

    2011-01-01

    CuInSe2 (CIS) films with good crystalline quality were synthesized by electrodeposition followed by annealing in Se vapor at 530 C. The morphology, composition, crystal structure,optical and electrical properties of the CIS films were investigated by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, Raman spectroscopy, UV-VISNIR spectroscopy, and admittance spectroscopy. The results revealed that the annealed CIS films had chalcopyrite structure and consisted of relatively large grains in the range of 500-1000 nm and single grain of films extend usually through the whole film thickness. The band gap of CIS films was 0.98 eV and carrier concentration was in the order of 1016 cm-3after etching the Cu-Se compounds on the film surface. Solar cells with the structure of AZO/i-ZnO/CdS/CIS/Mo/glass were fabricated. Current density vs. voltage test under standard reported condition showed the solar cells with an area of 0.2 cm2 had a conversion efficiency of 0.96%. The underlying physics was also discussed.

  15. Silver sulfotellurides from volcanic-hosted massive sulfide deposits in the Southern Urals

    Science.gov (United States)

    Novoselov, K. A.; Belogub, E. V.; Zaykov, V. V.; Yakovleva, V. A.

    2006-07-01

    This paper addresses Ag-sulfotellurides occurring in volcanic-hosted massive sulfide deposits of the Southern Urals. Cervelleite-like minerals were identified in ores from the Gayskoe, Yaman-Kasy, Severo-Uvaryazhskoe, Tash-Tau, and Babaryk deposits, where they occur in ores containing chalcopyrite, galena, sphalerite, tennantite ± bornite. Other Ag- and Te-bearing minerals (electrum, hessite, stromeyerite and Ag-bearing chalcocite) are present in the association. A benleonardite-like mineral associated with sylvanite and native tellurium was found as a metastable phase in paleohydrothermal tubes relics from the Yaman-Kasy deposit. Formation of the sulfotellurides indicates relative low fTe2 in the hydrothermal systems, insufficient for formation of most S-free tellurides. The significant Cu enrichment in cervelleite relates to the association with bornite. Broad variations in composition and physical properties of cervelleite-like sulfotellurides allow the supposition of the presence of several, as yet unnamed mineral species, which can be distinguished by Cu contents, Te/S ratios, and presumably by crystal structure.

  16. Tellurium-bearing minerals in zoned sulfide chimneys from Cu-Zn massive sulfide deposits of the Urals, Russia

    Science.gov (United States)

    Maslennikov, V. V.; Maslennikova, S. P.; Large, R. R.; Danyushevsky, L. V.; Herrington, R. J.; Stanley, C. J.

    2013-02-01

    Tellurium-bearing minerals are generally rare in chimney material from mafic and bimodal felsic volcanic hosted massive sulfide (VMS) deposits, but are abundant in chimneys of the Urals VMS deposits located within Silurian and Devonian bimodal mafic sequences. High physicochemical gradients during chimney growth result in a wide range of telluride and sulfoarsenide assemblages including a variety of Cu-Ag-Te-S and Ag-Pb-Bi-Te solid solution series and tellurium sulfosalts. A change in chimney types from Fe-Cu to Cu-Zn-Fe to Zn-Cu is accompanied by gradual replacement of abundant Fe-, Co, Bi-, and Pb- tellurides by Hg, Ag, Au-Ag telluride and galena-fahlore with native gold assemblages. Decreasing amounts of pyrite, both colloform and pseudomorphic after pyrrhotite, isocubanite ISS and chalcopyrite in the chimneys is coupled with increasing amounts of sphalerite, quatz, barite or talc contents. This trend represents a transition from low- to high sulphidation conditions, and it is observed across a range of the Urals deposits from bimodal mafic- to bimodal felsic-hosted types: Yaman-Kasy → Molodezhnoye → Uzelga → Valentorskoye → Oktyabrskoye → Alexandrinskoye → Tash-Tau → Jusa.

  17. Investigation of AgInS{sub 2} thin films grown by coevaporation

    Energy Technology Data Exchange (ETDEWEB)

    Arredondo, C A; Gordillo, G [Departamento de Fisica, Universidad Nacional de Colombia, Bogota (Colombia); J, Clavijo, E-mail: caarredondoo@unal.edu.c, E-mail: ggordillog@unal.edu.c [Departamento de Quimica, Universidad Nacional de Colombia, Bogota, Cr.30 N0 45-03 (Colombia)

    2009-05-01

    AgInS{sub 2} thin films were grown on soda-lime glass substrates by co-evaporation of the precursors in a two-step process. X-ray diffraction (XRD) measurements indicated that these compounds grow in different phases and with different crystalline structure depending upon the deposition conditions. However, through a parameter study, conditions were found to grow thin films containing only the AgInS{sub 2} phase with chalcopyrite type structure. In samples containing a mixture of several phases, the contribution in percentage terms of each phase to the whole compound was estimated with the help of the PowderCell simulation package. It was also found that the AgInS{sub 2} films present p-type conductivity, a high absorption coefficient (greater than 10{sub 4} cm{sub -1}) and an energy band gap Eg of about 1.95 eV, indicating that this compound has good properties to perform as absorbent layer in thin film tandem solar cells. The effect of the deposition conditions on the optical and morphological properties was also investigated through spectral transmitance and atomic force microscopy (AFM) measurements.

  18. Physics of Quantum Structures in Photovoltaic Devices

    Science.gov (United States)

    Raffaelle, Ryne P.; Andersen, John D.

    2005-01-01

    There has been considerable activity recently regarding the possibilities of using various nanostructures and nanomaterials to improve photovoltaic conversion of solar energy. Recent theoretical results indicate that dramatic improvements in device efficiency may be attainable through the use of three-dimensional arrays of zero-dimensional conductors (i.e., quantum dots) in an ordinary p-i-n solar cell structure. Quantum dots and other nanostructured materials may also prove to have some benefits in terms of temperature coefficients and radiation degradation associated with space solar cells. Two-dimensional semiconductor superlattices have already demonstrated some advantages in this regard. It has also recently been demonstrated that semiconducting quantum dots can also be used to improve conversion efficiencies in polymeric thin film solar cells. Improvement in thin film cells utilizing conjugated polymers has also be achieved through the use of one-dimensional quantum structures such as carbon nanotubes. It is believed that carbon nanotubes may contribute to both the disassociation as well as the carrier transport in the conjugated polymers used in certain thin film photovoltaic cells. In this paper we will review the underlying physics governing some of the new photovoltaic nanostructures being pursued, as well as the the current methods being employed to produce III-V, II-VI, and even chalcopyrite-based nanomaterials and nanostructures for solar cells.

  19. The genesis of the slab window-related Arzular low-sulfidation epithermal gold mineralization (eastern Pontides, NE Turkey

    Directory of Open Access Journals (Sweden)

    Enver Akaryalı

    2013-07-01

    Full Text Available The Arzular mineralization is one of the best examples of epithermal gold deposits in the eastern Pontides orogenic belt. The mineralization is hosted by the subduction-related basaltic andesites and is mainly controlled by E–W and NE–SW trending fracture zones. The main ore minerals are galena, sphalerite, pyrite, chalcopyrite, tetrahedrite and gold. Homogenization temperatures of fluid inclusions are between 130 and 295 °C for quartz and between 90 and 133 °C for sphalerite. Sulphur isotope values obtained from pyrite, galena and sphalerite vary between −1.2‰ and 3‰, indicating that sulphur belongs to magmatic origin and was derived from the Lutetian non-adakitic granitic intrusions in the region. Oxygen isotope values are between 15.0‰ and 16.7‰, and hydrogen isotope values are between −87‰ and −91‰. The sulphur isotope thermometer yielded temperatures in the range of 244–291 °C for the ore formation. Our results support the hypothesis that the Arzular mineralization is a low-sulfidation epithermal gold deposit associated with non-adakitic subduction-related granitic magmas that were generated by slab window-related processes in a south-dipping subduction zone during the Lutetian.

  20. The transition from porphyry- to epithermal-style gold mineralization at Ladolam, Lihir Island, Papua New Guinea: a reconnaissance study

    Science.gov (United States)

    Müller, Daniel; Kaminski, Klaus; Uhlig, Stephan; Graupner, Torsten; Herzig, Peter M.; Hunt, Steve

    2002-02-01

    The exceptionally large gold resource at Ladolam (>1,300 metric tons of gold), Lihir Island, resulted from the transition of an early-stage, low-grade porphyry gold system to a low-sulfidation epithermal gold event. This transition was probably triggered by rapid decompression during the partial slope failure of Luise stratovolcano and accompanied by the ingress of seawater. The original porphyry stage is indicated by remnant hydrothermal breccia clasts of strongly biotite-magnetite altered monzodiorite with disseminated pyrite ± chalcopyrite and poorly developed pyrite ± quartz stockwork veins. The breccias are overprinted by biotite-magnetite alteration and their matrix is strongly mineralized with disseminated auriferous pyrite. The breccias are cut by late-stage epithermal quartz-chalcedony-illite-adularia-pyrite veins and associated illite-adularia alteration that locally contain bonanza gold grades of up to 120 g/t. Isotope data suggest a magmatic source of sulfur in the gold-bearing fluids at Ladolam. Electronic supplementary material to this paper can be obtained by using the Springer LINK server located at http://dx.doi.org/10.1007/s00126-001-0230-y

  1. AN APPROACH TOWARDS STANDARDIZATION OF SWARNA MAKSHIK BHASMA (AN AYURVEDIC PREPARATION

    Directory of Open Access Journals (Sweden)

    Lagad C. E.

    2011-03-01

    Full Text Available Swarna Makshik (Chalco-pyrite, a mineral having various therapeutic uses in Pandu (Anemia, Kushtha (Skin disorders and Kamala (Jaundice has been used since long in Ayurveda. The present study was conducted to standardize raw and processed swarna makshik using techniques which can be used by pharmacies. Powdered swarna makshik was heated in an iron pan by adding lemon juice for 3 days till liberation of sulphur fumes stopped completely. Bhasma of this purified swarna makshik was obtained by triturating it with purified sulphur and lemon juice. It was then subjected to heat in 13 putas, and for firing in each puta, 3.5 kg cow dung cakes were used. To assure the quality of bhasma, rasa shastra quality control tests like nischandratva, varitara, amla pariksha, etc., were used. After the bhasma complied with these tests, the bhasma was analyzed using X-ray Diffraction (XRD and Thermo Gravimetric analysis (TGA revealed that SM bhasma contains Fe2O3, FeS2, CuS and SiO2. It may be concluded that raw SM is a complex compound which gets converted into a mixture of simple compounds after the particular process of marana.

  2. Mass-spectrometric REE analysis in sulphide minerals

    Directory of Open Access Journals (Sweden)

    Irina R. Elizarova

    2012-01-01

    Full Text Available The standard samples of diorite, granite and anorthosite (National Centre for Petrographic and Geochemical Research (CRPG CNRS, Nancy, France were analyzed to measure rare-earth element (REE concentrations by the ICP MS method (quadrupole ELAN 9000 DRC-e without preliminary dilution and concentration procedures. The certified values of REE concentrations measured on ELEMENT-2 mass-spectrometer by ICP MS method in Nancy are also well reproduced on ELAN 9000. The mass-spectrometer analytical environment and modes of operation were adjusted to detect REE in sulphide minerals by the example of the pyrite from the PGE Penikat layered intrusion (Finland and chalcopyrite from the Talnakh deposit (Kazakhstan. The total REE content in the pyrite is ca. 3.5 ppm, that is enough to establish Sm-Nd age of pyrite. By the example of State Standard Sample 2463 (Apatite, Russia it is shown how to apply the mineral/chondrite spectra to evaluate the accuracy of the REE analytical results.

  3. Study on mineralization at Jian copper deposit, Fars province, using petrographical and geochemical data

    Directory of Open Access Journals (Sweden)

    Mohamad Ali Rajabzade

    2013-04-01

    Full Text Available Jian Cu deposit is hosted by Surian volcano-sedimentary complex of Permo-Triassic age on the eastern edge of the Sanandaj-Sirjan metamorphic zone at a distance of 195 km from Shiraz, southwestern Iran. The complex consists mainly of metabasalt, chlorite-quartz schist, chlorite-muscovite schist, mica schist and graphite schist. Pyrite is the most important sulfide and chalcopyrite is the major Cu-bearing mineral occurring as disseminated grains and veinlets in host chlorite-quartz schist and chlorite-muscovite schist. Chondrite-normalized REE pattern of metabasalt with La/LuN=2/9 indicates mantle tholeiitic basalt as the source of metamorphosed igneous rocks. Geochemical data on the metabasalts, especially the content of immobile elements (e.g., Ti and High Field Strength Elements (HFSE (e.g., Zr، Nb and Y, show low degree of partial melting for parental magma with E-MORB affinity. Chloritic, silicification and minor sericitic assemblages are the main alteration types associated with the Jian Cu deposit. The Y/Ho ratio of Cu ores varies from 29.9 to 32.5, indicating the important role of sea water in the mineralizing system. Petrographical and geochemical data indicate that the Jian Cu deposit was formed as volcano-sedimentary hosted massive sulfide. The Ishikawa alteration index (AI in association with chlorite-carbonate-pyrite index (CCP is useful for the geochemical exploration of Cu deposits in the study area.

  4. Thin film photoelectric converter; Hakumaku koden henkan soshi

    Energy Technology Data Exchange (ETDEWEB)

    Mori, K.; Takamizawa, M.; Sakaguci, A.

    1996-07-30

    Ib-IIIb-VIb group compound semiconductor represented by CuInSe2 having chalcopyrite crystalline structure is promising as a material for making thin film and high efficient solar cells. The problem with the solar cell elements fabricated using this material, however, is variance in the characteristics of photoelectric conversion. This invention relates to improvement of the ununiformity of the photoelectric conversion property by the use of a glass substrate, which contains each of the alkali and alkali earth elements such as Na, K, Ba, Sr, and Ca in the ratio of less than 1% of the substrate weight, and a thin film photoelectric converter structured containing a photoelectric conversion layer whose main components are the elements selected out of each Ib group, IIIb group, and VIb group. In addition, the uniformity of the photoelectric conversion layer can be further improved if one or more than two kinds of elements with larger than 1.70 angstrom atomic radius are contained in the photoelectric conversion layer in the ratio from 5ppm to 5 wt%. 1 fig.

  5. Critical Factors Controlling Pd and Pt Potential in Porphyry Cu–Au Deposits: Evidence from the Balkan Peninsula

    Directory of Open Access Journals (Sweden)

    Demetrios G. Eliopoulos

    2014-03-01

    Full Text Available Porphyry Cu–Au–Pd±Pt deposits are significant Au resources, but their Pd and Pt potential is still unknown. Elevated Pd, Pt (hundreds of ppb and Au contents are associated with typical stockwork magnetite-bornite-chalcopyrite assemblages, at the central parts of certain porphyry deposits. Unexpected high grade Cu–(Pd+Pt (up to 6 ppm mineralization with high Pd/Pt ratios at the Elatsite porphyry deposit, which is found in a spatial association with the Chelopech epithermal deposit (Bulgaria and the Skouries porphyry deposit, may have formed during late stages of an evolved hydrothermal system. Estimated Pd, Pt and Au potential for porphyry deposits is consistent with literature model calculations demonstrating the capacity of aqueous vapor and brine to scavenge sufficient quantities of Pt and Pd, and could contribute to the global platinum-group element (PGE production. Critical requirements controlling potential of porphyry deposits may be from the metals contained in magma (metasomatized asthenospheric mantle wedge as indicated by significant Cr, Co, Ni and Re contents. The Cr content may be an indicator for the mantle input.

  6. Spatially resolved characterization of chemical species and crystal structures in CuInS{sub 2} and CuGa{sub x} Se{sub y} thin films using Raman microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Schmid, Thomas; Zenobi, Renato [Department of Chemistry and Applied Biosciences, ETH Zurich (Switzerland); Camus, Christian; Lehmann, Sebastian; Abou-Ras, Daniel; Lux-Steiner, Martha Christina [Helmholtz Centre Berlin for Materials and Energy, Berlin (Germany); Fischer, Christian-Herbert [Helmholtz Centre Berlin for Materials and Energy, Berlin (Germany); Free University Berlin, Institute of Chemistry, Berlin (Germany)

    2009-05-15

    This study demonstrates the potential of Raman microscopy in the analysis of thin film cross-sections. Raman maps of the photovoltaic material CuInS{sub 2} (CIS), which was prepared by the spray ion layer gas reaction method, revealed the spatial distribution of two different CIS modifications - chalcopyrite-type and CuAu I-type CIS - as well as contaminants and segregates with a lateral resolution of approx. 400 nm. Additionally, the chemical heterogeneity of a CuGaSe{sub 2}/CuGa{sub 3}Se{sub 5} bi-layer stack was clearly resolved. Raman microscopy provides a convenient way to simultaneously probe the chemical and structural properties of a sample. Based on Raman spectra, chemical species and even different crystal structures of inorganic compounds can be identified. Knowledge of the distribution of different phases and contaminants in thin films is crucial for further improvements of the coating process. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  7. Cu in In{sub 2}S{sub 3}: interdiffusion phenomena analysed by high kinetic energy X-ray photoelectron spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Pistor, P.; Allsop, N.; Caballero, R.; Camus, C.; Grimm, A.; Johnson, B.; Kropp, T.; Lauermann, I.; Lehmann, S.; Schorr, S.; Weber, A.; Klenk, R. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH (HZB), Berlin (Germany); Braun, W.; Gorgoi, M. [Berliner Elektronenspeicherring-Gesellschaft fuer Synchrotronstrahlung m.b.H., Berlin (Germany); Fischer, Ch.-H. [Helmholtz-Zentrum Berlin fuer Materialien und Energie GmbH (HZB), Berlin (Germany); Freie Universitaet Berlin (Germany). Fachbereich Physik; Moenig, H. [Freie Universitaet Berlin (Germany). Fachbereich Physik

    2009-05-15

    Chalcopyrite thin film solar cells with an In{sub 2}S{sub 3} buffer showed high efficiencies above 15%, but only after annealing at 200 C. One possible explanation is a Cu interdiffusion at the absorber/buffer interface. We were able to directly measure a Cu interdiffusion with a new tool at the BESSY synchrotron facility: HIKE (high kinetic energy X-ray photoelectron spectroscopy). Due to its increased information depth of up to 10-20 nm HIKE is able to provide chemical information even through thin closed overlayers. The HIKE endstation also allows in-situ heating. A layer stack of In{sub 2}S{sub 3}/ Cu(In,Ga)Se{sub 2} was prepared and heated in-situ up to a temperature of 300 C while continuously measuring HIKE spectra. A strong increase of the Cu signal above temperatures around 200 C was found. With this setup we were able to directly monitor the Cu diffusion from the absorber into the buffer layer. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  8. Synthesis of highly non-stoichiometric Cu2ZnSnS4 nanoparticles with tunable bandgaps

    Science.gov (United States)

    Hamanaka, Yasushi; Oyaizu, Wataru; Kawase, Masanari; Kuzuya, Toshihiro

    2017-01-01

    Non-stoichiometric Cu2ZnSnS4 nanoparticles with average diameters of 4-15 nm and quasi-polyhedral shape were successfully synthesized by a colloidal method. We found that a non-stoichiometric composition of Zn to Cu in Cu2ZnSnS4 nanoparticles yielded a correlation where Zn content increased with a decrease in Cu content, suggesting formation of lattice defects relating to Cu and Zn, such as a Cu vacancy (VCu), antisite with Zn replacing Cu (ZnCu), and/or defect cluster of VCu and ZnCu. The bandgap energy of Cu2ZnSnS4 nanoparticles systematically varies between 1.56 and 1.83 eV depending on the composition ratios of Cu and Zn, resulting in a wider bandgap for Cu-deficient Cu2ZnSnS4 nanoparticles. These characteristics can be ascribed to the modification in electronic band structures due to formation of VCu and ZnCu on the analogy of ternary copper chalcogenide, chalcopyrite CuInSe2, in which the top of the valence band shifts downward with decreasing Cu contents, because much like the structure of CuInSe2, the top of the valence band is composed of a Cu 3 d orbital in Cu2ZnSnS4.

  9. Neyshabour turquoise mine: the first Iron Oxide Cu-Au-U-LREE (IOCG mineralized system in Iran

    Directory of Open Access Journals (Sweden)

    Mohammad Hasan Karimpour

    2011-11-01

    Full Text Available Neyshabour turquoise mine is located in northwest of Neyshabour, southern Quchan volcanic belt. Eocene andesite and dacite forming as lava and pyroclastic rocks cover most of the area. Subvolcanic diorite to syenite porphyry (granitoids of magnetite series intruded the volcanic rocks. Both volcanic and subvolcanic rocks are highly altered. Four types of alteration are recognized including: silicification, argillic, calcification and propylitic. Silicification is dominant followed by argillic alteration. Mineralization is present as stockwork, disseminated and hydrothermal breccia. Hypogene minerals are pyrite, magnetite, specularite, chalcopyrite, and bornite. Secondary minerals are turquoise, chalcocite, covellite, and iron oxides. A broad zone of gossan has developed in the area. Oxidized zone has a thickness of about 80 m. Mineralized samples show high anomalies of Cu, Au, Zn, As, Mo, Co, U, LREE, Nb, and Th. Both aeromagnetic and radiometric (U and Th maps show very strong anomalies (10 × 5km within the mineralized area. Based on geology, alteration, mineralization, geochemistry, and geophysics, Neyshabour turquoise mine is a large Iron oxide Cu-Au-U-LREE (IOCG mineralized system. In comparison with other IOCG deposits, it has some similarities with Olympic Dam (Australia and Candelaria (Chile. In comparison with Qaleh Zari and Kuh Zar mines, Neyshabour turquoise mine is the first Iron oxide Cu-Au-U-LREE (IOCG mineralized system discovered in Iran.

  10. 黄铁矿和黄铜矿中铁铜钴镍的纸层析及定量测定

    Institute of Scientific and Technical Information of China (English)

    中国科学院贵阳地球化学研究所中心分析室

    1973-01-01

    The method of paper chromatography for the separation and quantitative determination of iron, copper, cobalt and nickel in pyrite and chalcopyrite is described.The three systems of ehromtograpbie solvents for the separation of iron, copper, cobalt and nickel on the 8×25 or 15×26 cm Whatman No. 3, involving acetone-hydrochloric acid-water, butanone-hydrochloric acid-water and acetone-acetylacetone-hydrochloric acid-water have been tested. As a developing system for the separation of this four elements in samples, the mixture of aoetone-acetylacetone-hydroehlorio acid-water is considered to be the best. After developing in a 30×40 cm glass dryer, the paper is dried in air and rendered the zone visible by treatment with 0.1% (W/V) rubeanic acid solution. The R1 values, colour reactions with this spray reagent and the eolour are given. A good paper chromatography of elements has been obtained. The elements are determined by colorimetrie method, with 1-nitroso-2-naphthol for cobalt,1-(2-pyridylozo)-2-naphthol for nickel, oxalic acid bis-cyelohexylidene hydrozide for copper, and sulfosalicylic acid for iron. In addition, iron and copper can also be determined by titration with potassium dichromate solution and iodimetry respectively.

  11. Optical properties and defect levels in a surface layer found on CuInSe{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Abulfotuh, F.; Wangensteen, T.; Ahrenkiel, R.; Kazmerski, L.L. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    In this paper the authors have used photoluminescence (PL) and wavelength scanning ellipsometry (WSE) to clarify the relationship among the electro-optical properties of copper indium diselenide (CIS) thin films, the type and origin of dominant defect states, and device performance. The PL study has revealed several shallow acceptor and donor levels dominating the semiconductor. PL emission from points at different depths from the surface of the CIS sample has been obtained by changing the angle of incidence of the excitation laser beam. The resulting data were used to determine the dominant defect states as a function of composition gradient at the surface of the chalcopyrite compound. The significance of this type of measurement is that it allowed the detection of a very thin layer with a larger bandgap (1.15-1.26 eV) than the CIS present on the surface of the CIS thin films. The presence of this layer has been correlated by several groups to improvement of the CIS cell performance. An important need that results from detecting this layer on the surface of the CIS semiconductor is the determination of its thickness and optical constants (n, k) as a function of wavelength. The thickness of this surface layer is about 500 {Angstrom}.

  12. Ore mineralogy and textural zonation in the world-class epithermal Waihi Vein System, Hauraki Goldfield

    Science.gov (United States)

    Mauk, Jeffrey L.; Skinner, Erin G; Fyfe, Sarah J; Menzies, Andrew H; Lowers, Heather A.; Koenig, Alan E.

    2016-01-01

    The Waihi district in the Hauraki Goldfield of New Zealand contains adularia-sericite epithermal gold-silver veins that have produced more than 7.7 Moz gold. The outermost veins of the district (Martha, Favona, Moonlight, and Cowshed) contain abundant colloform, cherty, and black quartz fill textures, with minor crustiform and massive quartz. The central veins (Amaranth, Trio, and Union) contain predominantly massive and crustiform textures, and these veins are also commonly coarser grained than outermost veins. Pyrite, sphalerite, galena, chalcopyrite, electrum, and acanthite occur in both outermost and central veins; base metal sulfide minerals typically increase in abundance in deeper samples. Antimony-, arsenic-, and selenium-bearing minerals are most abundant in the Favona and Moonlight veins, whereas base metal sulfide minerals are more abundant in the central veins at Correnso. Throughout the Waihi vein system, electrum is by far the most widespread, abundant, and significant gold-bearing mineral, but LA-ICP-MS analyses show that arsenian pyrite also contains some gold. Mineralogical and textural data are consistent with the central veins forming at a deeper structural level, or from hydrothermal fluids with different chemistry, or both.

  13. Advances in research of sulphide ore textures and their implications for ore genesis

    Institute of Scientific and Technical Information of China (English)

    GU Lianxing; ZHENG Yuanchuan; TANG Xiaoqian; WU Changzhi; HU Wenxuan

    2006-01-01

    Important advances in research of sulphide ore textures in recent years have deepened our understanding of ore genesis of related mineral deposits. Pressure solution of sulphide minerals has been suggested as a mechanism for remobilization of ore materials,whereas pressure solution of the gangues is believed to raise the grade of the primary ores. We have known that precipitation of base metal sulphides from fluids prefers crystal and crack surfaces of pyrite to form overgrowth. Therefore, pyrite-bearing embryo beds in a sedimentary sequence can be acted as effective crystal seed beds and are favorable for fluid overprinting to form huge statabound deposits. Texture studies of various sulphides can be used to interpret the entire history of sedimentation, diagenesis, deformation and metamorphism of the ores. The study of chalcopyrite disease in sphalerite has brought about the idea of zone refining, and given a new explanation to metal zonation in massive sulphide deposits. Ductile shearing of sulphide ores may form ore mylonites, which will become oreshoots enriched in Cu, Au and Ag during late-stage fluid overprinting. Despite that various modern analytical techniques are being rapidly developed, ore microscopy remains to be an unreplaceable tool for ore geologists. Combined with these modern techniques, this tool will help accelerate the development of theories on ore genesis.

  14. Temperature dependency of the Ga/In distribution in Cu(In,Ga)Se2 absorbers in high temperature processes

    Science.gov (United States)

    Mueller, B. J.; Demes, T.; Lill, P. C.; Haug, V.; Hergert, F.; Zweigart, S.; Herr, U.

    2016-05-01

    The current article reports about the influence of temperature and glass substrate on Ga/In interdiffusion and chalcopyrite phase formation in the stacked elemental layer process. According to the Shockley-Queisser limit the optimum for single junction devices is near 1.4 eV, which is strongly coupled on the Ga/(Ga+In) ratio of Cu(In,Ga)Se2 thin film solar cells. To increase the Ga content in the active region of the Cu(In,Ga)Se2 a 70:30 CuGa alloy target is used. An increase of the selenization temperature leads to a more homogeneous Ga/In distribution and a less pronounced Ga agglomeration at the back contact. The Ga/In interdiffusion rates for different selenization temperatures and substrates were estimated with the model of a two layer system. At the highest selenization temperature used an absorber band gap of 1.12 eV was realized, which is similar to typical values of absorbers produced during the co-evaporation process. The Na diffusion into the Cu(In,Ga)Se2 is weakly temperature dependent but strongly influenced by the choice of the glass substrate composition.

  15. Effect of electrodeposition potential on composition and morphology of CIGS absorber thin film

    Indian Academy of Sciences (India)

    N D Sang; P H Quang; L T Tu; D T B Hop

    2013-08-01

    CuInGaSe (CIGS) thin films were deposited on Mo/soda-lime glass substrates by electrodeposition at different potentials ranging from −0.3 to −1.1 V vs Ag/AgCl. Cyclic voltammetry (CV) studies of unitary Cu, Ga, In and Se systems, binary Cu–Se, Ga–Se and In–Se systems and quaternary Cu–In–Ga–Se were carried out to understand the mechanism of deposition of each constituent. Concentration of the films was determined by energy dispersive spectroscopy. Structure and morphology of the films were characterized by X-ray diffraction and scanning electron microscope. The underpotential deposition mechanism of Cu–Se and In–Se phases was observed in voltammograms of binary and quaternary systems. Variation in composition with applied potentials was explained by cyclic voltammetry (CV) data. A suitable potential range from −0.8 to −1.0 V was found for obtaining films with desired and stable stoichiometry. In the post-annealing films, chalcopyrite structure starts forming in the samples deposited at −0.5 V and grows on varying the applied potential towards negative direction. By adjusting the composition of electrolyte, we obtained the desired stoichiometry of Cu(In0.7Ga0.3)Se2.

  16. CuInGaS2 photocathodes treated with SbX3 (X  =  Cl, I): the effect of the halide on solar water splitting performance

    Science.gov (United States)

    Guijarro, Néstor; Prévot, Mathieu S.; Johnson, Melissa; Yu, Xiaoyun; Bourée, Wiktor S.; Jeanbourquin, Xavier A.; Bornoz, Pauline; Le Formal, Florian; Sivula, Kevin

    2017-02-01

    The realization of photoelectrochemical tandem cells for efficient solar-to-hydrogen energy conversion is currently impeded by the lack of inexpensive, stable, and efficient photocathodes. The family of sulfide chalcopyrites (CuIn x Ga1-x S2) has recently demonstrated a remarkable stability and performance even when prepared by solution-based routes that potentially lower the cost of fabrication. However, the photovoltage delivered by the photocathodes is still well-below the attainable values, a classical limitation linked to a large density of surface states in these materials. In the present work, we show that the identity of halide present during the growth of the solution-processed CuIn0.3Ga0.7S2 (CIGS) thin-films governs the overall performance by directing the crystal growth and the passivation of surface states. Replacing chlorine by iodine leads to CIGS photocathodes that deliver photocurrents of 5 mA cm-2 (at 0 V versus RHE) and a turn-on voltage of 0.5 V versus RHE without charge extracting overlayer nor any sign of deterioration during stability test.

  17. A New Heterotrophic Strain for Bioleaching of Low Grade Complex Copper Ore

    Directory of Open Access Journals (Sweden)

    Kaijian Hu

    2016-02-01

    Full Text Available A new heterotrophic strain, named Providencia sp. JAT-1, was isolated and used in bioleaching of low-grade complex copper ore. The strain uses sodium citrate as a carbon source and urea as a nitrogen source to produce ammonia. The optimal growth condition of the strain is 30 C, initial pH 8, sodium citrate 10 g/L and urea 20 g/L, under which the cell density and ammonia concentration in the medium reached a maximum of 4.83 × 108 cells/mL and 14 g/L, respectively. Ammonia produced by the strain is used as the main lixiviant in bioleaching. Bioleaching results revealed that higher strain growth led to a higher copper recovery, while higher pulp density will cause a greater inhibitory effect on strain growth and ammonia production. The copper extraction reached the highest value of 54.5% at the pulp density of 1%. Malachite, chrysocolla and chalcocite are easy to leach out in this bioleaching system while chalcopyrite is difficult. Results of comparative leaching experiments show that bioleaching using JAT-1 is superior to ammonia leaching at the same condition. The metabolites produced by the strain other than ammonia are also involved in bioleaching.

  18. The sulfide ore looping oxidation process: An alternative to current roasting and smelting practice

    Science.gov (United States)

    McHugh, Larry F.; Balliett, Robert; Mozolic, Jean A.

    2008-07-01

    This novel method utilizes the reactions of metal sulfides and metal oxides. It is applicable to single-metal systems such as Mo, Cu, Co, Ni, Fe, and Zn individual sulfides and to mixed sulfides such as chalcopyrite and Mo/Fe. In addition to primary ores, waste stream products such as spent catalysts can be effectively processed. The benchmark work done on MoS2/MoO3 resulted in an MoO2 product with less than 0.095 wt.% sulfur. Other sulfide concentrate materials showed similar results. In the first stage of the looping process, a highly concentrated SO2 off-gas stream is produced that could be directed to an acid plant or converted to liquid. The products from the first process step can be directed down line for further processing or can be used as is. In the second step of looping oxidation, the product is oxidized back to its fully oxidized state and is mainly looped back to drive the oxidation process in the first reaction. There are also several opportunities for energy recovery and conversion, making looping oxidation an energy-efficient process.

  19. 金川三矿区低品位铜镍矿石工艺矿物学研究%Study on the Process Mineralogy of Low-grade Copper-nickel Ore in Jinchuan No.3 Deposit Area

    Institute of Scientific and Technical Information of China (English)

    程少逸; 赵礼兵; 袁致涛; 赵毕文

    2011-01-01

    The prooess mineralogy study was made to identify the mineral composition, occurrence forms of coppernickel, and the dissemination characteristics of main minerals in low-grade copper-nickel ores of Jinchuan No. 3 deposit.The results showed that copper and nickel ores mainly occurs in form of pentlandite, violarite, chalcopyrite and wallerite,but other sulfides and gangues have close and complex dissemination relation with these minerals.Serpentine has a critical argillic alteration, which brings unfavorable effect on the separation of copper and nickel.%通过工艺矿物学研究,查明了金川二矿区低品位铜镍矿石的矿物组成、铜镍的赋存形式及主要有用矿物的嵌布特性.研究结果表明:矿石中的铜、镍主要以镍黄铁矿、紫硫镍铁矿、黄铜矿、墨铜矿形式存在,但其他硫化矿物及脉石矿物与它们嵌布关系密切而复杂;矿石蛇纹石蚀变严重,易于泥化.这些将给铜、镍的分选带来不利影响.

  20. Highlights of the Salt Extraction Process

    Science.gov (United States)

    Abbasalizadeh, Aida; Seetharaman, Seshadri; Teng, Lidong; Sridhar, Seetharaman; Grinder, Olle; Izumi, Yukari; Barati, Mansoor

    2013-11-01

    This article presents the salient features of a new process for the recovery of metal values from secondary sources and waste materials such as slag and flue dusts. It is also feasible in extracting metals such as nickel and cobalt from ores that normally are difficult to enrich and process metallurgically. The salt extraction process is based on extraction of the metals from the raw materials by a molten salt bath consisting of NaCl, LiCl, and KCl corresponding to the eutectic composition with AlCl3 as the chlorinating agent. The process is operated in the temperature range 973 K (700°C) to 1173 K (900°C). The process was shown to be successful in extracting Cr and Fe from electric arc furnace (EAF) slag. Electrolytic copper could be produced from copper concentrate based on chalcopyrite in a single step. Conducting the process in oxygen-free atmosphere, sulfur could be captured in the elemental form. The method proved to be successful in extracting lead from spent cathode ray tubes. In order to prevent the loss of AlCl3 in the vapor form and also chlorine gas emission at the cathode during the electrolysis, liquid aluminum was used. The process was shown to be successful in extracting Nd and Dy from magnetic scrap. The method is a highly promising process route for the recovery of strategic metals. It also has the added advantage of being environmentally friendly.

  1. Evidence of p- to n-type inversion at CIGS grain boundaries: A depth-dependent surface electron microscopy study

    Science.gov (United States)

    Chan, Calvin; Ohta, Taisuke; Kellogg, Gary; Mansfield, Lorelle; Noufi, Rommel

    2014-03-01

    Chalcopyrite Cu(In1-xGax)Se2 (CIGS) is an interesting photovoltaic material because it holds the laboratory record for thin-film solar power conversion efficiency (η > 20 %) despite its disordered microcrystalline structure. However, commercialization of this technology has been limited by structural and chemical variations in CIGS films. Many microscopic and spectroscopic studies have shown built-in electric potentials (Φbi) at CIGS grain boundaries. This may assist with electron-hole separation, but the reported magnitude and statistical distribution of Φbi remains inconsistent between studies. In this work, photoemission and low-energy electron microscopies (PEEM and LEEM) were used to reconcile these reported differences. Highly surface sensitive PEEM measurements showed Φbi ~ 0 . 5 V, which was consistent with most other reports. However, more bulk sensitive LEEM measurements showed Φbi ~ 1 . 5 V, which strongly suggests p- to n-type inversion at CIGS grain boundaries. This formation of pn junctions at CIGS grain boundaries is likely responsible for the high performance of CIGS photovoltaics. Sandia is managed by Sandia Corp., a subsidiary of Lockheed Martin, for the U.S. DOE NNSA (DE-AC04-94AL85000). Work was supported by an U.S. DOE EERE SunShot Bridging Research Interactions through collaborative Development Grants in Energy (BRIDGE).

  2. Mechanochemically Synthesized CIGS Nanocrystalline Powder for Solar Cell Application

    Directory of Open Access Journals (Sweden)

    Bharati Rehani

    2013-05-01

    Full Text Available Copper Indium Gallium Diselenide (CIGS is a compound semiconductor material from the group of I-III-VI. The material is a solid solution of copper, indium and selenium (CIS and copper, gallium and selenium with an empirical formula of CuIn(1 – xGaxSe2, where 0  x  1. CIGS has an exceptionally high absorption coefficient of more than 105 cm – 1 for 1.5 eV. Solar cells prepared from absorber layers of CIGS materials have shown an efficiency higher than 20 %. CuIn(1 – xGaxSe2 (x  0.3 nanocrystalline compound was mechanochemically synthesized by high-energy milling in a planetary ball mill. The phase identification and crystallite size of milled powders at different time intervals were carried out by X-ray diffraction (XRD. The XRD analysis indicates chalcopyrite structure and the crystallite size of about 10 nm of high-energy milled CIGS powder after two and half hours of milling. An attempt for preparing the thin film from CIGS nanocrystalline powder was carried out using the flash evaporation technique. Scanning electron microscopy (SEM reveals uniform distribution of CIGS particles in thin film.

  3. The growth of heteroepitaxial CuInSe2 on free-standing N-polar GaN

    Directory of Open Access Journals (Sweden)

    Cheng-Hung Shih

    2014-12-01

    Full Text Available We report that chalcopyrite CuInSe2 thin films were grown on free-standing N-polar GaN (000 1 ̄ by molecular beam epitaxy. X-ray diffraction showed that the CuInSe2 thin film was grown in (112 orientation, and its peak of rocking curve with full width at half maximum of about 897.8 arc-sec indicated the epitaxial growth of CuInSe2 (112 film on N-polar GaN. Microstructure analysis of the CuInSe2  showed that the large lattice mismatch (28.5% between CuInSe2  and GaN is accommodated by domain matching, and no interface reaction occurs between CuInSe2 and GaN. Our experimental results show that GaN is stable for the epitaxial growth of CuInSe2 thin film, which exhibits a promising potential for optoelectronic applications.

  4. Structural and Electronic Properties Study of Colombian Aurifer Soils by Moessbauer Spectroscopy and X-ray Diffraction

    Energy Technology Data Exchange (ETDEWEB)

    Bustos Rodriguez, H., E-mail: hbustos@ut.edu.co; Rojas Martinez, Y.; Oyola Lozano, D. [Universidad del Tolima, Departamento de Fisica (Colombia); Perez Alcazar, G. A.; Fajardo, M. [Universidad del Valle, Departamento de Fisica (Colombia); Mojica, J. [Ingeominas Valle, Departamento de Geologia (Colombia); Molano, Y. J. C. [Universidad Nacional, Departamento de Geologia (Colombia)

    2005-02-15

    In this work a study on gold mineral samples is reported, using optical microscopy, X-ray diffraction (XRD) and Moessbauer spectroscopy (MS). The auriferous samples are from the El Diamante mine, located in Guachavez-Narino (Colombia) and were prepared by means of polished thin sections. The petrography analysis registered the presence, in different percentages that depend on the sample, of pyrite, quartz, arsenopyirite, sphalerite, chalcopyrite and galena. The XRD analysis confirmed these findings through the calculated cell parameters. One typical Rietveld analysis showed the following weight percent of phases: 85.0% quartz, 14.5% pyrite and 0.5% sphalerite. In this sample, MS demonstrated the presence of two types of pyrite whose hyperfine parameters are {delta}{sub 1} = 0.280 {+-} 0.002 mm/s and {Delta}{sub 1} = 0.642 {+-} 0.002 mm/s, {delta}{sub 2} = 0.379 {+-} 0.002 mm/s and {Delta}{sub 2} = 0.613 {+-} 0.002 mm/s.

  5. Cu(InAl)Se2薄膜太阳电池的研究进展%Recent Study Progress on Cu(InAl)Se2 Thin Film Solar Cell

    Institute of Scientific and Technical Information of China (English)

    自兴发; 杨培志; 王海蓉

    2012-01-01

    Thin film solar cells based on chalcopyrite thin films have gained increasing interest due to steady progress in conversion efficiencies. Cu(InAl)Se2 (CIAS) may be viable alternate for higher band gap than CuInSe2 (CIS) based solar cells because it requires less relative alloy concentration than Ga alloys to achieve comparable band gap. The different preparation methods and synthesis mechanism of CIAS materials with reference to the latest research progress are described. The preparation disadvantage and development trends of CIAS solar cell are also presented.%具有黄铜矿结构的CuInSe2 (CIS)类薄膜太阳电池随着其转换效率的进一步提高,受到日益广泛的关注.相对于CIS材料,Cu(InAl) Se2(CIAS)具有更高的禁带宽度,可用比Ga合金更小的相对浓度来实现更可观的带隙,CIAS有望取代CIS成为薄膜太阳电池的新型材料.结合最新研究进展论述了CIAS薄膜材料的不同制备方法及合成机理,并讨论了目前CIAS太阳电池研究中存在的问题和今后的发展方向.

  6. Abandoned mine slags analysis by EPMA WDS X-ray mapping

    Science.gov (United States)

    Guimarães, F.; Rosado, L.; Morais, C.; Candeias, A. E.; Pinto, A. P.; Mirão, J.

    2010-02-01

    Mining activity on the Iberian Pyritic Belt (Portugal and Spain) started before Phoenician times, became particularly intense during the Roman occupation of the Iberian Peninsula (for gold), and after the industrial revolution (for gold, copper, zinc, lead and sulphur). The commonest ore of this region is a massive polymetalic sulphide accumulation, where pyrite (FeS2) is the main mineral, with variable concentrations of chalcopyrite (CuFeS2), sphalerite (ZnS), galena (PbS), arsenopyrite (FeAsS2), other sulphides and sulfosalts which include minor elements like Mn, Co, Ni, Se, Cd, Sb, Te, Hg and Bi. Some of the main and minor elements of these ores are hazardous and the drainage basins of pollutant source areas often induce health concerns in the resident population. Electron probe microanalysis study followed previous optical and XRD analysis of the slags. The study focused on the identification of phases how sulphide and metallic phases are distributed within the material and infer about leachable elements during weathering. Electron probe X-ray maps show evidences of different behaviour between the elements: Ca and Zn are completely leached; iron is retained in oxyhydroxides, lead and arsenic precipitate as sulphates. Electron probe microanalysis studies are essential to understand complex materials as earth materials. Nevertheless, care is required to a correct interpretation of data and most quantitative compositional data are not trustworthy.

  7. Colloidal CuFeS2 Nanocrystals: Intermediate Fe d-Band Leads to High Photothermal Conversion Efficiency

    CERN Document Server

    Ghosh, S; Petrelli, A; Kriegel, I; Gaspari, R; Almeida, G; Bertoni, G; Cavalli, A; Scotognella, F; Pellegrino, T; Manna, L

    2016-01-01

    We describe the colloidal hot-injection synthesis of phase-pure nanocrystals (NCs) of a highly abundant mineral, chalcopyrite (CuFeS2). Absorption bands centered at around 480 and 950 nm, spanning almost the entire visible and near infrared regions, encompass their optical extinction characteristics. These peaks are ascribable to electronic transitions from the valence band (VB) to the empty intermediate band (IB), located in the fundamental gap and mainly composed of Fe 3d orbitals. Laser-irradiation (at 808 nm) of an aqueous suspension of CuFeS2 NCs exhibited significant heating, with a photothermal conversion efficiency of 49%. Such efficient heating is ascribable to the carrier relaxation within the broad IB band (owing to the indirect VB-IB gap), as corroborated by transient absorption measurements. The intense absorption and high photothermal transduction efficiency (PTE) of these NCs in the so-called biological window (650-900 nm) makes them suitable for photothermal therapy as demonstrated by tumor ce...

  8. Effect of Se flux on CuGaSe2 absorbers deposited on ITO-coated SLG substrates by using a three-stage co-evaporation process

    Science.gov (United States)

    Yoo, Jinsu; Eo, Young-Joo; Cho, Jun-Sik; Yun, Jae-Ho; Choi, Jang Hun; Kim, Kihwan; Park, Ju Hyung; Kong, Seong Ho

    2016-11-01

    As the key factor for top-cell application in a tandem structure, wide-bandgap chalcopyrite CuGaSe2 (CGS) absorbers were deposited at a thickness of 2 μm on soda-lime glass (SLG) which was coated with radio-frequency sputtered indium-tin-oxide (ITO) films. The semi-transparent CGS absorbers with a bandgap energy of 1.65 eV were grown by using a three-stage co-evaporation process with Cu, Ga, and Se elemental sources. During CGS absorber growth, the composition ratio [Cu]/[Ga] was fixed at about 0.85 and the Se-to-Ga flux ratio P [ Se]/[ Ga] was varied from 22 to 61 by increasing the temperature of the Se source. In this study, the compositional, structural, optical and electrical properties of top-cell CGS absorbers, which absorbed the short wavelength range of the solar spectrums for tandem solar cell application, were investigated as a function of the Se flux. On the basis of our experimental results, the highest CGS solar cell efficiency of 4.7 % in the cell structure described as Al/ZnO:Al/i-ZnO/CdS/CGS/ITO/SLG was demonstrated using a P [ Se]/[ Ga] value of 22.

  9. Growth and characterization of single phase AgInS2 crystals for energy conversion application through β-In2S3 by thermal evaporation

    Science.gov (United States)

    Gantassi, A.; Essaidi, H.; Ben Hamed, Z.; Gherouel, D.; Boubaker, K.; Colantoni, A.; Monarca, D.; Kouki, F.; Amlouk, M.; Manoubi, T.

    2015-03-01

    Silver indium sulfide thin films have been successfully synthesized out from β-In2S3 buffer layers using appropriate heat treatments of evaporated β-In2S3/Ag. X-ray analysis show that the β-In2S3/Ag crystalline films with 60 nm thickness of Ag, which were annealed under sulfur atmosphere at 400 °C, were mainly formed by the ternary AgInS2. Raman spectra confirmed that the observed peaks were characteristics to AgInS2 chalcopyrite of thin film structure. The optical band gap of AgInS2, which was evaluated as nearly 1.80 eV, was confirmed by the electrical study which yielded a value in the order of 1.78 eV. The electrical conductivity, conduction mechanism, dielectric properties and relaxation model of this thin film were studied using impedance spectroscopy technique in the frequency range 5 Hz-13 MHz under various temperatures (370-440 °C). Besides, complex impedance, AC conductivity and complex electric modulus have been investigated on the basis of frequency and temperature dependence.

  10. Homogeneity of single phase Cu(In,Ga)Se{sub 2} produced by selenisation of metal precursors: An optical investigation

    Energy Technology Data Exchange (ETDEWEB)

    Botha, J.R. [Department of Physics, P. O. Box 77000, Nelson Mandela Metropolitan University, Port Elizabeth, 6031 (South Africa)]. E-mail: reinhardt.botha@nmmu.ac.za; Schumacher, S.A. [Department of Physics, P. O. Box 77000, Nelson Mandela Metropolitan University, Port Elizabeth, 6031 (South Africa); Leitch, A.W.R. [Department of Physics, P. O. Box 77000, Nelson Mandela Metropolitan University, Port Elizabeth, 6031 (South Africa); Alberts, V. [Department of Physics, University of Johannesburg, P. O. Box 524, Auckland Park, Johannesburg, 2006 (South Africa)

    2006-07-26

    Two-stage processes involving the selenisation of metallic precursor layers are among the most promising techniques for the formation of chalcopyrite-based solar cell absorber layers on a commercial scale. In this paper, the homogeneity of Cu(In{sub 0.75}Ga{sub 0.25})Se{sub 2} prepared by a new two-stage technique [V. Alberts, Semicond. Sci. Technol., 19 (2004) 65.], which involves the selenisation of sputtered CuIn{sub 0.75}Ga{sub 0.25} precursor films in steps designed to control the reaction rates of the binary selenide phases and to prevent the formation of the more stable CuGaSe{sub 2} phase, is studied. Photoluminescence spectroscopy, optical absorption measurements and X-ray diffraction measurements confirm that layers grown by a traditional process, which involves a single selenisation step, contain separate quaternary phases: gallium-rich phases are found closer to the substrate, while gallium-poor phases reside near the front surface. Layers produced by the novel process do not show this grading. A line appearing at {approx} 0.8 eV is ascribed to Na{sub III}, which results from the out-diffusion of Na from the glass substrate.

  11. Ore Characteristics and Fluid Inclusion of the Base Metal Vein Deposit in Moncong Bincanai Area, Gowa, South Sulawesi, Indonesia

    Directory of Open Access Journals (Sweden)

    Asmariyadi Asmariyadi

    2014-07-01

    Full Text Available DOI: 10.17014/ijog.v7i4.146This paper is dealing with ore characteristics and fluid inclusion of the Moncong Bincanai, Biringbulu Subregency of Gowa Regency, South Sulawesi Province, Indonesia. The mineralization is a vein type, with the orientation of N170oE /65oSW, hosted in open-space filling within basalt. The mineralization consists of galena, sphalerite, chalcopyrite, and pyrite. Vein thickness ranges from 5 - 17 cm, showing a crustiform banding texture, with a sequence from outer to centre: quartz, carbonate (siderite, sulphide. The quartz displays primary growth textures such as comb, crystalline, saccharoidal, and colloform. Analytical methods applied include AAS and fluid inclusion microthermometry. Chemical composition of the vein indicates an average of Pb = 47.92%, Cu = 1.27%, Zn = 1.02%, and Fe = 9.46%, which shows a significant concentration of Pb. Fluid inclusion microthermometry results indicate a range of formation temperature of 240 - 250C and salinity of the responsible hydrothermal fluid of 2.1 - 2.5 wt.% NaCl eq. The deposit is categorized into low-sulfidation epithermal deposits, which was formed within a range of 410 - 440 m below paleosurface.

  12. Electrochemical mechanism of thioglycolic acid depressing sulphide minerals

    Institute of Scientific and Technical Information of China (English)

    2001-01-01

    The effects of thioglycolic acid (TGA) on the rest potential and zeta potential of sulphide minerals were studied and the electrochemical mechanism of TGA depressing sulphide minerals was put forward. Results of flotation test show that galena, pyrite and chalcopyrite can be well depressed by TGA, but sphalerite and arsenopyrite can not be depressed. Tests also show that TGA has a little influence on zeta potential of sulfide minerals covered by xanthate coatings and TGA can lower the rest potential of sulphide minerals. The electrochemical mechanism of TGA depressing sulphide minerals is that the dixanthogen adsorbing on the mineral surface will be unstable and reduced when rest potential value of sulphide mineral (φMS) is less than the reversible potential of reduction of dixanthogen to xanthate φX-|X2 in the presence of TGA, flotability of sulphide mineral becomes weak; inversely, the coatings of dixanthogen on mineral surface will keep stable when φMS>φX-|X2, sulphide mineral keeps flotability. In the system of mixed minerals, the electrochemical condition of separation of two sulphide minerals by TGA is φMS1<φX-|X2(φX-|PbX2)<φMS2.

  13. Geologic, geochemical, and isotopic studies of a carbonate- and siliciclastic-hosted Pb-Zn deposit at Lion Hill, Vermont

    Science.gov (United States)

    Foley, Nora K.; Clark, Sandra H.B.; Woodruff, Laurel G.; Mosier, Elwin L.

    1995-01-01

    Zn-, Pb-, Cu-, and Fe-bearing rocks of the Lion Hill area in western Vermont formed during the Early Cambrian by syngenetic sedimentary-exhalative and diagenetic replacement processes. Sphalerite, galena, chalcopyrite, pyrite, and, locally, magnetite form stratabound and broadly stratiform lenticular zones, -300 meters long and 25-50 meters thick, which are uneconomic at the present time. The lenses are structurally disrupted and metamorphosed to greenschist facies, probably due to the Taconic orogeny. Textural evidence suggests that mineralizing fluids permeated the sediments prior to lithification and that a dilatant fracture zone, possibly a feeder zone, contains some of the discordant veins at Lion Hill. The veins may have formed when the sediments were in a plastic, semiconsolidated state. The association of layered iron formation containing base-metal sulfide minerals provides possible lithologic evidence for syngenetic mineralization by submarine exhalative activity. Sand bars and tidal channels present in the sedimentary section could have acted as permeable pathways for movement of mineralizing fluids. The complex interlayering in the sedimentary sequence of carbonate and siliciclastic rock types having widely varying permeabilities created numerous fluid traps.

  14. Studies of non-vacuum processing of Cu-chalcogenide thin films.

    Science.gov (United States)

    El Hamri, E; Meddah, M; Boulkadat, L; Elfanaoui, A; Bouabid, K; Nya, M; Portier, X; Ihlal, A

    2012-08-01

    Cu-chalcogenide thin films were prepared using a two stage method: one step electrodeposition of CuISe and CIGSe, and the sulfurisation of CISe to prepare CISSe thin films. The films were deposited on different substrates: Mo and ITO coated glass. The optimum potentials for electrodeposition of CISe and CIGSe films were respectively selected in the range -400 to -550 mV and -650 to -700 mV (vs. SCE). The electrodeposited layers were firmly adhesive. The well known chalcopyrite structure appears after annealing at 400 degrees C under Argon for CISe. The band gap value deduced from the optical measurements is close to 1 eV. To increase this value, addition of gallium in the aqueous electrolytic solution was performed. A band gap value as high as 1.26 eV was recorded on the obtained CIGSe films. Sulfurisation of CISe layers under 5% H2S/Ar atmosphere lead to a shift of the position of the principal XRD peaks indicating the substitution of selenium atoms by sulfur atoms and thus the formation of the quaternary CISSe. Optical measurements performed on this quaternary compound show that our films exhibit a band gap value scaling from 1 eV to 1.4 eV depending on the amount of sulphur incorporated into the layers during the heat treatments.

  15. Correlation Between Microstructure and Optical Properties of Cu (In0.7, Ga0.3) Se2 Grown by Electrodeposition Technique

    Science.gov (United States)

    Chihi, Adel; Bessais, Brahim

    2016-09-01

    Polycrystalline thin films Cu (In0.7, Ga0.3) Se2 (CIGSe) were grown on copper foils at various cathodic potentials by using an electrodeposition technique. Scanning electron microscopy showed that the average diameter of CIGSe grains increase from 0.1 μm to 1 μm when the cathodic potential decreases. The structure and surface morphology were investigated by x-ray diffraction and atomic force microscopy (AFM) techniques. This structure study shows that the thin films were well crystallized in a chalcopyrite structure without unwanted secondary phases with a preferred orientation along (112) plane. Energy-dispersive x-ray analyses confirms the existence of CIGSe single phase on a copper substrate. AFM analysis indicated that the root mean square roughness decreases from 64.28 to 27.42 when the potential deposition increases from -0.95 V to -0.77 V. Using Raman scattering spectroscopy, the A1 optical phonon mode was observed in 173 cm-1 and two other weak peaks were detected at 214 cm-1 and 225 cm-1 associated with the B2 and E modes of the CIGSe phase. Through spectroscopy ellipsometry analysis, a three-layer optical model was exploited to derive the optical properties and layer thickness of the CIGSe film by least-squares fitting the measured variation in polarization light versus the obtained microstructure.

  16. Crystal structure re-investigation in wide band gap CIGSe compounds

    Energy Technology Data Exchange (ETDEWEB)

    Souilah, M. [Institut des Materiaux Jean Rouxel, Universite de Nantes, CNRS, 2 rue de la Houssiniere, BP 32229, 44322 Nantes Cedex 03 (France)], E-mail: marc.souilah@cnrs-imn.fr; Rocquefelte, X.; Lafond, A.; Guillot-Deudon, C. [Institut des Materiaux Jean Rouxel, Universite de Nantes, CNRS, 2 rue de la Houssiniere, BP 32229, 44322 Nantes Cedex 03 (France); Morniroli, J.-P. [Laboratoire de Metallurgie Physique et Genie des Materiaux, UMR CNRS 8517, USTL and ENSCL, Bat C6, Cite Scientifique, 59655 Villeneuve d' Ascq Cedex (France); Kessler, J. [Institut des Materiaux Jean Rouxel, Universite de Nantes, CNRS, 2 rue de la Houssiniere, BP 32229, 44322 Nantes Cedex 03 (France)

    2009-02-02

    There is agreement in the literature that Cu(In{sub 1} {sub -} {sub x}Ga{sub x})Se{sub 2} (CIGSe) absorber used in solar cells has an optimum composition (x {approx} 0.3) corresponding to a band gap (1.1-1.2 eV) far below the theoretical value giving the maximum (1.4-1.5 eV). This paper presents a re-investigation of the crystal structure of bulk CIGSe compounds for both stoichiometric and Cu-poor compositions. Regardless of the gallium content, all the stoichiometric compounds are found to adopt the well-known chalcopyrite structure (space group I-42d) while a modification of the structure is evidenced for the high Ga-content Cu-poor compounds. The X-ray diffraction analyses demonstrate that the crystal structure of Cu{sub 0.743}In{sub 0.543} Ga{sub 0.543}Se{sub 2} is derived from that of the stannite structure (space-group I-42m). Ab-initio calculations show a strong dependence of the electronic structure near the Fermi level with the copper content. Such modifications are expected to significantly change the optical properties of Cu-poor CIGSe materials.

  17. Cation ratio fluctuations in Cu2ZnSnS4 at the 20 nm length scale investigated by analytical electron microscopy

    Energy Technology Data Exchange (ETDEWEB)

    Aguiar, Jeffery A. [National Renewable Energy Laboratory, Golden CO 80401 USA; Erkan, Mehmet E. [Department of Electrical and Computer Engineering, University of Utah, UT 84112 USA; Pruzan, Dennis S. [Department of Materials Science and Engineering, University of Utah, UT 84112 USA; Nagaoka, Akira [Department of Materials Science and Engineering, University of Utah, UT 84112 USA; Department of Applied Physics and Electronic Engineering, University of Miyazaki, Miyazaki 889 2192 Japan; Yoshino, Kenji [Department of Applied Physics and Electronic Engineering, University of Miyazaki, Miyazaki 889 2192 Japan; Moutinho, Helio [National Renewable Energy Laboratory, Golden CO 80401 USA; Al-Jassim, Mowafak [National Renewable Energy Laboratory, Golden CO 80401 USA; Scarpulla, Michael A. [Department of Electrical and Computer Engineering, University of Utah, UT 84112 USA; Department of Materials Science and Engineering, University of Utah, UT 84112 USA

    2016-04-05

    Kesterite Cu2ZnSn(S,Se)4 (CZTSSe) is a sustainable material for thin-film photovoltaics with device efficiencies greater than 12% have been demonstrated. Despite similar crystal structure and polycrystalline film microstructures, there is widespread evidence for larger-amplitude potential and bandgap fluctuations in CZTS than in the analogous Cu(In,Ga)Se2 (CIGSe) chalcopyrite material. This disorder is believed to account for a sizable part of the larger open-circuit voltage (VOC) deficit in CZTS devices, yet the detailed origins and length scales of these fluctuations have not been fully elucidated. Herein, we present a transmission electron microscopy study focusing on composition variation within bulk multicrystals of CZTS grown by the travelling heater method (THM). In these slow-cooled, solution grown crystals we find direct evidence for spatial composition fluctuations of amplitude <1 at.% (~5 x 1020 cm-3) and thus, explainable by point defects. However, rather than being homogeneously-distributed we find a characteristic 20 nm length scale for these fluctuations, which sets a definite length scale for band gap and potential fluctuations. At Σ3 grain boundaries, we find no evidence of composition variation compared to the bulk. The finding highlights such variations reported at grain boundaries in polycrystalline thin-films are direct consequences of processing methods and not intrinsic properties of CZTS itself.

  18. Structural and optical properties of CuInxGa1-xSe2 thin films prepared by flash evaporation

    Science.gov (United States)

    Benslim, N.; Cowache, P.; Hannech, E. B.; Benabdeslem, M.; Béchiri, L.; Mahdjoubi, L.

    2002-11-01

    CuInxGa1-xSe2 (CIGSe) thin films with x = 0.5 and 0.75 were deposited by a single source vacuum thermal evaporated method 'Flash' on molybdenum coated glass. Some of these films were annealed in selenium atmosphere. X-ray diffraction and energy dispersive x-ray measurements have indicated that these films contain exclusively a phase with a chalcopyrite structure. The morphology, grain distributions and composition of the CIGSe films were studied and compared for x = 0.5 and x = 0.75. The optical studies have shown that the films are highly absorbing (7 × 104 cm-1). The absorption edge is shifted to high photon energies when the gallium concentration is increased. After selenization, the bandgaps increase from 1.00 eV to 1.18 eV for x = 0.75 and from 1.16 eV to 1.28 eV for x = 0.5.

  19. Na incorporation into Cu(In,Ga)Se2 thin-film solar cell absorbers deposited on polyimide: Impact on the chemical and electronic surface structure

    Science.gov (United States)

    Song, X.; Caballero, R.; Félix, R.; Gerlach, D.; Kaufmann, C. A.; Schock, H.-W.; Wilks, R. G.; Bär, M.

    2012-02-01

    Na has deliberately been incorporated into Cu(In,Ga)Se2 ("CIGSe") chalcopyrite thin-film solar cell absorbers deposited on Mo-coated polyimide flexible substrates by adding differently thick layers of NaF in-between CIGSe absorber and Mo back contact. The impact of Na on the chemical and electronic surface structure of CIGSe absorbers with various Cu-contents deposited at comparatively low temperature (420 °C) has been studied using x-ray photoelectron and x-ray excited Auger electron spectroscopy. We observe a higher Na surface content for the Cu-richer CIGSe samples and can distinguish between two different chemical Na environments, best described as selenide-like and oxidized Na species, respectively. Furthermore, we find a Cu-poor surface composition of the CIGSe samples independent of Na content and — for very high Na contents — indications for the formation of a (Cu,Na)-(In,Ga)-Se like compound. With increasing Na surface content, also a shift of the photoemission lines to lower binding energies could be identified, which we interpret as a reduction of the downward band bending toward the CIGSe surface explained by the Na-induced elimination of InCu defects.

  20. Cu(In,Ga)Se{sub 2}-based thin-film systems with different absorber thicknesses: spatially resolved photoluminescence and AFM measurements

    Energy Technology Data Exchange (ETDEWEB)

    Neumann, Oliver; Heise, Stephan J.; Brueggemann, Rudolf; Meessen, Max; Bauer, Gottfried H. [Institute of Physics, Carl von Ossietzky University, Oldenburg (Germany); Witte, Wolfram; Hariskos, Dimitrios [Zentrum fuer Sonnenenergie- und Wasserstoff-Forschung Baden-Wuerttemberg (ZSW), Stuttgart (Germany)

    2011-07-01

    Chalcopyrite absorbers exhibit spatial inhomogeneities in structural, optical and optoelectronic properties. We study the absorber thickness dependent behavior of the local properties such as the splitting of the quasi-Fermi levels, optical threshold energies and surface roughness of Cu(In,Ga)Se{sub 2}-based (CIGSe) thin-film systems with different absorber thicknesses, which are realized by etching traditionally prepared absorbers with nominal thicknesses of about 2 {mu}m with bromine-methanol followed by a cadmium sulfide (CdS) passivation. AFM measurements reveal a decrease in the surface roughness with decreasing absorber thickness, i.e., increasing etching time. Photoluminescence experiments with high lateral resolution allow the extraction of the optical threshold energies and the splitting of the quasi-Fermi levels. Furthermore we verify a depth gradient of the gallium concentration and a variation of quasi-Fermi level splitting depending on the absorber thickness. Additionally, we show that the CdS/CIGSe junction formation of an unetched absorber in comparison to an etched absorber leads to higher quasi-Fermi level splitting.

  1. Cu(In{sub 1-x}Ga{sub x})Se{sub 2} co-evaporated thin films from simple tungsten baskets-Influence of the gallium source

    Energy Technology Data Exchange (ETDEWEB)

    Drici, A. [LEREC, Departement de Physique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)], E-mail: abdelaziz.drici@univ-annaba.org; Mekhnache, M.; Bouraoui, A. [LEREC, Departement de Physique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria); Kachouane, A.; Bernede, J.C. [LAMP, 2 Rue de la Houssiniere, BP 92208, 44322 Nantes Cedex (France); Amara, A.; Guerioune, M. [LEREC, Departement de Physique, Universite Badji Mokhtar, BP 12, Annaba 23000 (Algeria)

    2008-07-15

    Cu(In{sub 1-x}Ga{sub x})Se{sub 2} (CIGSe) thin films with 0 {<=} x {<=} 1 are grown by co-evaporation. Cu, In and Ga elements are evaporated from simple tungsten baskets, while Se is evaporated from broad Ta basket. Different combinations of the metal sources have been tested using three and two tungsten baskets. It is shown that, when deposited on a substrate heated at 500 deg. C, the Ga is present throughout the thickness of the films whatever the technique used. X-ray photoelectron spectroscopy (XPS measurements have shown that Ga depth profile is more reliable in that case. X-ray diffraction shows that the films crystallize in the expected chalcopyrite structure. The lattice parameters decrease with increasing Ga atomic percentage. It is revealed that the optical band gap increases with the Ga content and yielded a bowing parameter around 0.28. The best results have been obtained with the four sources technique. Thin film solar cells, Mo/CIGSe/In{sub 2}S{sub 3-x}O{sub 3x}/i-ZnO/ZnO:Al/Ni-Al grid, have been fabricated and probed. The efficiency of the cells depends strongly in the film composition but also in the metal source number.

  2. Effects of heat treatments on the properties of Cu(In,Ga)Se{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, SeJin; Kim, ChaeWoong; Yun, JaeHo; Lee, JeongChul; Yoon, KyungHoon [Solar Cells Research Center, Korea Institute of Energy Research, 71-2 Jang-dong, Yuseong-gu, Daejeon 305-343 (Korea)

    2007-11-23

    Effects of heat treatment in nitrogen or Se atmosphere on the properties of Cu(In,Ga)Se{sub 2} (CIGS) nanoparticles were investigated to extract optimum sintering conditions for fabrication of solar cell applicable CIGS absorber films. In nitrogen atmosphere, as the temperature increases from 100 to 400 C the intensity of X-ray diffraction (XRD) peaks corresponding to the (1 1 2), (2 2 0) and (3 1 2) planes of the chalcopyrite CIGS increases, and the peak positions shift to lower angle regions without any particle growth in scanning electron microscopy (SEM) analysis, which is in consistent with the significant In and Ga loss in the EDS data. When the temperature further goes up to 500 C, parts of CIGS are decomposed and Cu and CuSe{sub 2} phases are observed. From these results, the heat treatment in nitrogen atmosphere is found to have no beneficial effect on the sintering of the particles and only induces loss of In and Ga. On the other hand, heat treatment in Se atmosphere at a substrate temperature of 550 C with Se vapor evaporated at 250 and 450 C provided much enhanced growth of the particles, specially up to 500 nm at 450 C, and increased crystallinity without In or Ga loss, reflecting that Se supply played a critical role in the growth of the CIGS nanoparticles. (author)

  3. CZTSSe thin film solar cells: Surface treatments

    Science.gov (United States)

    Joglekar, Chinmay Sunil

    Chalcopyrite semiconducting materials, specifically CZTS, are a promising alternative to traditional silicon solar cell technology. Because of the high absorption coefficient; films of the order of 1 micrometer thickness are sufficient for the fabrication of solar cells. Liquid based synthesis methods are advantageous because they are easily scalable using the roll to roll manufacturing techniques. Various treatments are explored in this study to enhance the performance of the selenized CZTS film based solar cells. Thiourea can be used as a sulfur source and can be used to tune band gap of CZTSSe. Bromine etching can be used to manipulate the thickness of sintered CZTSSe film. The etching treatment creates recombination centers which lead to poor device performance. Various after treatments were used to improve the performance of the devices. It was observed that the performance of the solar cell devices could not be improved by any of the after treatment steps. Other surface treatment processes are explored including KCN etching and gaseous H2S treatments. Hybrid solar cells which included use of CIGS nanoparticles at the interface between CZTSSe and CdS are also explored.

  4. Heat transfer law in leaching dump

    Institute of Scientific and Technical Information of China (English)

    WU Ai-xiang; WANG Hong-jiang; XI Yong; YANG Bao-hua; LI Jian-feng; YIN Sheng-hua; ZHA Ke-bing

    2005-01-01

    Based on the law of temperature changes in the leaching dump and the forming process of heat flux, the basic balance equation of heat flow in dump was established, the dissipated heat flow from dump to the atmosphere was analyzed to estimate the surface temperature of the ore particle in dump and discover the law of forced heat convection of heat flow transfer in dump. And the lixiviate flow formula taking a certain heat flow out of dump was deduced by using the inversion method. Through theoretic analysis, combining Dexing copper mine heap leaching production practice, the results show that the heat flow of chalcopyrite leaching emitted is not so great, but the heat flow of pyrite leaching and sulphur oxidation produced take up a higher proportion of total heat flow; the dissipated heat flow takes up a lower proportion, and most of heat flow is absorbed by itself, thus the inside temperature rises gradually; and the saturation flow form for leaching is adopted, which makes the lixiviate seepage in the transitional flow or even in the turbulent flow, so as to accelerate the heat flow diffusing and keep the leaching dump temperature suitable for bacteria living.

  5. Typomorpic Characteristics of the Major Minerals in the Puziwan Gold Deposit, Datong, Shanxi, China

    Institute of Scientific and Technical Information of China (English)

    QING Min; NIU Cuiyi; LEI Shibin

    2008-01-01

    Utilizing theories of minerageny and prospecting mineralogy, the authors studied theattitude, morphotype and chemical composition of metallic minerals of pyrite, gold, chalcopyrite,galena and sphalerite, non-metallic minerals of quartz, carbonate, dolomite and rutile in the Puziwangold deposit. The study shows the following results. (1) The mineral assemblage is complex and thespecies of sulfide are abundant with occurrences of sulfosalt minerals. (2) The composition in theminerals is complex and there rich micro elements, including As, Sb, Bi, Se, Te, Au, Ag, Cu, Pb, Zn, andCr, Ni, V. The typomorphic characteristics of the association of the elements and their specific valuesuggest that gold mineralization is associated with shallow magmatic hydrothermai activity, the ore-forming fluid is the mixture of abundant rising alkali magmatic water originating from the mantle orthe lower crust and the descending acid atmospheric water. (3) Ankerite, Fe-rich sphalerite, granularTi-rich rutile are widely distributed, which indicate great denudation depths, high mineralizationtemperature. The deposit is found in the middle and shallow positions of the porphyry series. The deeplayers are not favorable for gold mineralization. (4) Copper minerals are rich in the ores and sulfideshave high content of copper, suggesting possible porphyry-type Cu (Au) mineralization in deeppositions and the surrounding areas.

  6. Effects of europium substitution for In on structure and photoelectric properties of CuIn1-xEuxTe2

    Science.gov (United States)

    Nie, Xiaomeng; Guo, Yongquan

    2016-01-01

    The structures and optical and electric properties of europium doped CuIn1-xEuxTe2 have been studied systematically using powder X-ray diffraction (XRD), scanning electron microscopy (SEM) with energy dispersive spectrum (EDS), ultraviolet and visible spectrophotometer (UV-vis), and standard four-probe method. The studies reveal that the minor europium doping into CuIn1-xEuxTe2 could still stabilize the chalcopyrite structure in a solid solution of x=0.1. The lattice parameters are going up with increasing the content of europium in CuIn1-xEuxTe2 due to the size effect at In site. The structural refinement confirms that Eu partly substitutes for In and occupies the 4b crystal position. SEM morphologies show that the europium doping into CuIn1-xEuxTe2 can fine the grains from the largely agglomerated state to the uniformly separated state. The electrical resistivities of single phase CuIn1-xEuxTe2 follow a mixture model of hopping conductivity and variable range hopping conductivity. The absorption band-gaps of CuIn1-xEuxTe2 at room temperature tend to increase with increasing Eu content. CuIn1-xEuxTe2 might be a good candidate for photovoltaic cell.

  7. A comparative study of thin films of Zn(O;OH)S and In(O;OH)S deposited on CuInS2 by chemical bath deposition method

    Science.gov (United States)

    Vallejo, W.; Quiñones, C.; Gordillo, G.

    2012-04-01

    In this work, a study of synthesis of thin films of Zn(O;OH)S and In(O;OH)S deposited by chemical bath deposition (CBD) is presented. The thin films of Zn(O;OH)S and In(O;OH)S were deposited from different chemical bath systems on absorber layers of CuInS2 (CIS), indium tin oxide substrates (ITO) and soda lime glass substrates (SL). The differences on the growth rate, optical, morphological and structural properties of the thin films Zn(O;OH)S and In(O;OH)S are studied. The Growth studies showed that thin films of Zn(O;OH)S and In(O;OH)S grown faster on CIS than on SL and ITO substrates. The optical and morphological studies showed that both thin films present high transmittance in visible electromagnetic spectrum and covered uniformly the surface of the substrate, furthermore it was observed that thin films of Zn(O;OH)S and In(O;OH)S were polycrystalline. Finally, the results suggest that thin films of Zn(O;OH)S and In(O;OH)S obtained in this work could be used as buffer layer to replace the thin films of CdS, which are conventionally used as buffer layer in chalcopyrite based solar cells.

  8. Solution-based colloidal synthesis of hybrid P3HT: Ternary CuInSe2 nanocomposites using a novel combination of capping agents for low-cost photovoltaics

    Science.gov (United States)

    Sharma, Shailesh Narain; Chawla, Parul; Akanksha; Srivastava, A. K.

    2016-06-01

    In this work, ternary CuInSe2 (CISe) chalcopyrite nanocrystallites efficiently passivated by a novel combination of capping agents viz: aniline and 1-octadecene during chemical route synthesis were dispersed in conducting polymer matrix poly(3-hexylthiophene) (P3HT). By varying the composition and concentration of the ligands, the properties of the resulting CISe nanocrystallites and its corresponding polymer nanocomposites thus could be tailored. The structural, morphological and optical studies accomplished by various complimentary techniques viz. Transmission Electron Microscopy (TEM), Contact angle, Photoluminescence (PL) and Raman have enabled us to compare the different hybrid organic (polymer)-inorganic nanocomposites. On the basis of aniline-octadecene equilibrium phase diagram, the polydispersity of the CISe nanocrystals could be tuned by using controlled variations in the reaction conditions of nucleation and growth such as composition of the solvent and temperature. To the best of author's knowledge, the beneficial effects of both the capping agents; aniline and octadecene contributing well in tandem in the development of large-sized (100-125 nm) high quality, sterically- and photo-oxidative stable polycrystalline CISe and its corresponding polymer (P3HT):CISe composites with enhanced charge transfer efficiency has been reported for the first time. The low-cost synthesis and ease of preparation renders this method of great potential for its possible application in low-cost hybrid organic-inorganic photovoltaics. The figure shows the Temperature vs Mole fraction graph of two different phases (aniline and 1-octadecene) in equilibrium.

  9. Effect of antimony incorporation on structural properties of CuInS{sub 2} crystals

    Energy Technology Data Exchange (ETDEWEB)

    Ben Rabeh, M., E-mail: mohamedbenrabeh@yahoo.f [Laboratoire de Photovoltaique et Materiaux Semi-Conducteurs - ENIT BP 37, Le belvedere, 1002 Tunis (Tunisia); Chaglabou, N., E-mail: nadia_chaglabou@yahoo.f [Laboratoire de Photovoltaique et Materiaux Semi-Conducteurs - ENIT BP 37, Le belvedere, 1002 Tunis (Tunisia); Kanzari, M., E-mail: Mounir.Kanzari@ipeit.rnu.t [Laboratoire de Photovoltaique et Materiaux Semi-Conducteurs - ENIT BP 37, Le belvedere, 1002 Tunis (Tunisia)

    2010-02-15

    CuInS{sub 2} (CIS) single crystals doped with 1, 2, 3 and 4 atomic percent (at.%) of antimony (Sb) were grown by the horizontal Bridgman method. The effect of Sb doping on the structural properties of CIS crystal was studied by means of X-ray diffraction (XRD), energy dispersive X-ray analysis (EDAX), scanning electron microscopy (SEM) and PL measurements. X-ray diffraction data suggests that the doping of Sb in the CIS single crystals does not affect the tetragonal (chalcopyrite) crystal structure and exhibited a (1 1 2) preferred orientation. In addition, with increasing Sb concentration, the X-ray diffraction analysis show that Sb doped CIS crystals are more crystallized and the diffraction peaks of the CuInS{sub 2} phase were more pronounced in particular the (1 1 2) plane. EDAX study revealed that Sb atoms can occupy the indium site and/or occupying the sulfur site to make an acceptor. PL spectra of undoped and Sb doped CIS crystals show two emission peaks at 1.52 and 1.62 eV, respectively which decreased with increasing atomic percent antimony. Sb doped CIS crystals show p-type conductivity.

  10. Raman scattering and structural analysis of electrodeposited CuInSe{sub 2} and S-rich quaternary CuIn(S,Se){sub 2} semiconductors for solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Izquierdo-Roca, Victor; Fontane, Xavier; Morante, Joan Ramon [Departament d' Electronica, Universitat de Barcelona (Spain); Saucedo, Edgardo; Ruiz, Carmen M.; Grand, Pierre-Philippe; Jaime-Ferrer, Jesus Salvador; Bermudez, Veronica [Institut de Recherche et Developement sur l' Energie Photovoltaique (IRDEP), Chatou (France); Calvo-Barrio, Lorenzo [Departament d' Electronica, Universitat de Barcelona (Spain); Lab. Analisis de Superficies, SCT, Universitat de Barcelona (Spain); Alvarez-Garcia, Jacobo [Centre de Recerca i Investigacio de Catalunya (CRIC), Barcelona (Spain); Perez-Rodriguez, Alejandro

    2009-05-15

    This work reports the Raman scattering characterisation of CuInSe{sub 2} precursors grown by single step electrodeposition and the corresponding layers recrystallised under sulphurising conditions for solar cell devices. The analysis of the spectra measured on the as-grown precursors has allowed identifying the main secondary phases in these layers with elemental Se, Cu-Se phases and chalcopyrite Cu-poor ordered vacancy domains. To deepen in the identification of the Cu-Se phases, these measurements have been correlated with the analysis of binary Cu-Se layers. The experimental data indicate that formation of both Se and Cu-Se phases is likely controlled by the Se content in the layers. For values of stoichiometry below 1.15, excess Cu in the layers is accommodated in a phase with very low Raman efficiency (as Cu{sub 2}Se). Increasing the content of Se leads to an increase in the spectral contribution from both Se and Cu{sub 2-x}Se, being the formation of these phases likely favoured under high excess Se conditions. The characterisation of the corresponding recrystallised layers has allowed analysing the impact of the presence of the secondary phases in the as-grown absorbers on the performance of the final solar cells. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  11. On the occurrence of gold mineralizations in southeastern Ivory Coast

    Science.gov (United States)

    Kadio, E.; Coulibaly, Y.; Allialy, M. E.; Kouamelan, A. N.; Pothin, K. B. K.

    2010-07-01

    Gold mineralizations are known to occur in the Paleoproterozoic (Birimian) formations of the Aboisso area, southeastern Ivory Coast. These formations, which have been structured during the Eburnean orogeny, mainly consist of volcanic, volcaniclastic and sedimentary rocks intruded by granitic, basic and ultrabasic plutons. Exploration of these terranes has revealed numerous gold mineralizations, the most significant of which are located in the Aféma shear zone. Four distinct types of mineralizations can be distinguished based on the typology of the host rocks. These include mineralizations enclosed in highly silicified volcanic rocks (type 1), mineralizations closely related to intense silicification of metasedimentary rocks (type 2), mineralizations associated with silicified polygenic conglomerates (type 3), and mineralizations encountered in brecciated and silicified zones within a metadiorite sill (type 4). Gold is observed either as free gold, or in association with pyrite, arsenopyrite, sphalerite, chalcopyrite, ±pyrrhotite, ±galena, ±anatase, ±monazite, ±magnetite. Gold and the various sulfides are mostly of hydrothermal epigenetic origin. The fact that the gold mineralizations occurs in brecciated and silicified zones around granitoid intrusions clearly indicates that post-magmatic hydrothermal activity and tectonics exerted a major control during the mineralization process.

  12. A new strain Acidithiobacillus albertensis BY-05 for bioleaching of metal sulfides ores

    Institute of Scientific and Technical Information of China (English)

    XIA Jin-lan; PENG An-an; HE Huan; YANG Yu; LIU Xue-duan; QIU Guan-zhou

    2007-01-01

    An acidophilic, rod-shaped Gram-negative sulfur oxidizing strain BY-05 was isolated from an acid mine drainage of copper ore in Baiyin area, Gansu Province, China. Ultrastructural studies show that the isolate has a tuft of polar flagella and possesses sulfur granules with clear membrane adhering to the cell innermembrane. Physiological study shows that this isolate grows autotrophically and aerobically by oxidizing S0 and reduced inorganic sulfur compounds (S2O2-3,S2O2-4,S2- and ZnS) with the optimum growth at pH 3.5-4.0 and at the temperature range of 25-30 ℃. The 16S rRNA gene sequence (DQ 423683) of strain BY-05 has 100% sequence similarity to that of Acidithiobacillus albertensis (DSM 14366). So it is identified and named as A. albertensis BY-05. Bioleaching experiments with this new strain show that it can play an important role in recovery of metals from chalcopyrite and sphalerite.

  13. Metabolomic study of Chilean biomining bacteria Acidithiobacillus ferrooxidans strain Wenelen and Acidithiobacillus thiooxidans strain Licanantay.

    Science.gov (United States)

    Martínez, Patricio; Gálvez, Sebastián; Ohtsuka, Norimasa; Budinich, Marko; Cortés, María Paz; Serpell, Cristián; Nakahigashi, Kenji; Hirayama, Akiyoshi; Tomita, Masaru; Soga, Tomoyoshi; Martínez, Servet; Maass, Alejandro; Parada, Pilar

    2013-02-01

    In this study, we present the first metabolic profiles for two bioleaching bacteria using capillary electrophoresis coupled with mass spectrometry. The bacteria, Acidithiobacillus ferrooxidans strain Wenelen (DSM 16786) and Acidithiobacillus thiooxidans strain Licanantay (DSM 17318), were sampled at different growth phases and on different substrates: the former was grown with iron and sulfur, and the latter with sulfur and chalcopyrite. Metabolic profiles were scored from planktonic and sessile states. Spermidine was detected in intra- and extracellular samples for both strains, suggesting it has an important role in biofilm formation in the presence of solid substrate. The canonical pathway for spermidine synthesis seems absent as its upstream precursor, putrescine, was not present in samples. Glutathione, a catalytic activator of elemental sulfur, was identified as one of the most abundant metabolites in the intracellular space in A. thiooxidans strain Licanantay, confirming its participation in the sulfur oxidation pathway. Amino acid profiles varied according to the growth conditions and bioleaching species. Glutamic and aspartic acid were highly abundant in intra- and extracellular extracts. Both are constituents of the extracellular matrix, and have a probable role in cell detoxification. This novel metabolomic information validates previous knowledge from in silico metabolic reconstructions based on genomic sequences, and reveals important biomining functions such as biofilm formation, energy management and stress responses. ELECTRONIC SUPPLEMENTARY MATERIAL: The online version of this article (doi:10.1007/s11306-012-0443-3) contains supplementary material, which is available to authorized users.

  14. Preservation of Thiobacillus ferrooxidans and Thiobacillus thiooxidans with activity check.

    Science.gov (United States)

    Gupta, S G; Agate, A D

    1986-01-01

    Cultures of Thiobacillus ferrooxidans and Thiobacillus thiooxidans, used in biohydrometallurgical processes of economic importance, are very difficult to preserve by conventional methods. Hence, to preserve the cultures with their activity intact, various techniques were tried, after determining their respective activity in terms of Iron Oxidation Rate (IOR) and Sulfur Oxidation Rate (SOR). Among the methods tested, along with the recommended method of serial transfer in a liquid medium, were methods such as lyophilization, storage in a liquid nitrogen and mixing with sterile, inert carriers like lignite or chalcopyrite ores. After a period check-up at 4 months and 8 months storage, it was found that out of these methods, mixing with sterile ore followed by storage at 8 degrees C, kept both types of activities intact. The temperature of storage was observed to have a definite effect on activity, in that when the preserved cultures were stored at 8 degrees C, the activity was retained, whereas at 28-30 degrees C (RT) storage, the activity of all the cultures preserved by various techniques, dropped significantly.

  15. Progress in Polycrystalline Thin-Film Cu(In,GaSe2 Solar Cells

    Directory of Open Access Journals (Sweden)

    Udai P. Singh

    2010-01-01

    Full Text Available For some time, the chalcopyrite semiconductor CuInSe2 and its alloy with Ga and/or S [Cu(InGaSe2 or Cu(InGa(Se,S2], commonly referred as CIGS, have been leading thin-film material candidates for incorporation in high-efficiency photovoltaic devices. CuInSe2-based solar cells have shown long-term stability and the highest conversion efficiencies among all thin-film solar cells, reaching 20%. A variety of methods have been reported to prepare CIGS thin film. Efficiency of solar cells depends upon the various deposition methods as they control optoelectronic properties of the layers and interfaces. CIGS thin film grown on glass or flexible (metal foil, polyimide substrates require p-type absorber layers of optimum optoelectronic properties and n-type wideband gap partner layers to form the p-n junction. Transparent conducting oxide and specific metal layers are used for front and back contacts. Progress made in the field of CIGS solar cell in recent years has been reviewed.

  16. The development of 6.7% efficient copper zinc indium selenide devices from copper zinc indium sulfide nanocrystal inks

    Science.gov (United States)

    Graeser, Brian K.

    As solar cell absorber materials, alloys of CuIn(S,Se)2 and Zn(S,Se) provide an opportunity to reduce the usage of indium along with the ability to tune the band gap. Here we report successful synthesis of alloyed (CuInS2)0.5(ZnS)0.5 nanocrystals by a method that solely uses oleylamine as the liquid medium for synthesis. The reactive sintering of a thin film of these nanocrystals via selenization at 500 °C results in a uniform composition alloy (CuIn(S,Se)2)0.5(Zn(S,Se)) 0.5 layer with micron size grains. Due to the large amount of zinc in the film, the sintered grains exhibit the zinc blende structure instead of the usual chalcopyrite structure of CuIn(S,Se)2 films. The use of the selenide films as a p-type absorber layer has yielded solar cells with total area power conversion efficiencies as high as 6.7% (7.4% based on active area). These preliminary results are encouraging and indicate that with further optimization this class of materials has promise as the absorber layer in solar cells.

  17. Geological structure, composition of ores and age of the Bamsk gold deposit, Amur region, Russia

    Institute of Scientific and Technical Information of China (English)

    Vitaly A. Stepanov

    2004-01-01

    The Bamsk gold-ore deposit is located in the Amur region, the Far East of Russia. It is confined to the Early Cretaceous volcanic-plutonic uplift of central type, located in the Stanov folded-clumpy Pre-Cambrian system. The deposit is presented by a series of gold-bearing quartz and carbonate-quartz vein-stringer zones. They are confined to the super-intrusive zone of the Nevachansk subvolcanic intrusion of sienite-porphyric composition. The mineralization is being controlled by zone of fractures developed in the autochthone ofthe Bamsk fault. Quartz, carbonates and sericite prevail in the composition of ores. The quantity of ore minerals doesn't exceed 1%~5%. Pyrite, chalcopyrite, galena and native gold are widely spread. Sheelite, gold and silver tellurides, sulphobismuthites, acanthite, sphalerite and cinnabar are less developed. Four stages of mineralization have been distinguished. Gold-sulphide-sulphosalt ore with tellurides of gold and silver is productive for gold. The following set of elements is typomorphic for the ores of the deposit: Au, Ag, Cu, Bi,Mo, Pb and Sb (W1, Pb1, Mo) -Cu- (Ag, Bi, Sb, Mn, W1, Pb2) form the vertical series of zoning. Rocks, enclosing the mineralization are exposed to the processes of listvenitization-beresitization. The processes of gumbeization and argillization are less manifested. The age of the gold mineralization, determined by Rb-Sr method on ore-accompanying minerals, is 130.6 Ma.

  18. Tetrahedrite-Group Minerals in the Jinjitai Gold Deposit, Western Sichuan

    Institute of Scientific and Technical Information of China (English)

    2000-01-01

    There are quite a few tetrahedrite-group minerals in the Jinjitai gold deposit, western Sichuan, which occur in an interstratified fractured zone of Middle Devonian carbonate rock series. The gold ore consists of pyrite, chalcopyrite, tetrahedrite-group minerals, galena, sphalerite and gold-silver series minerals, with an element association of Au-Cu-Ag-Pb-As-Sb-Bi. Electron microprobe analyses of the tetrahedrite-group minerals gave the following results: copper 40.04 to 42.27% (average 40.04%), iron 1.24 to 7.78% (average 4.13%), zinc 0.39 to 7.06% (average 3.58%), arsenic 5.41 to 17.40% (average 8.84%), antimony 2.70 to 20.46% (average 15.87%), and silver 0.02 to 0.73% (average 0.28%). The mineral varieties include zinc-antimony-tetrahedrite, iron-antimony-tetrahedrite, iron-tennatite and zincotennatite. These data show that there is a complete isomorphous series between Sb and As. From above downwards tetrahedrite varies from zinc- and antimony-rich to iron- and arsenic-rich compositions. Their occurrence and zonal features are very important for exploration of the same type of gold deposits in western Sichuan.

  19. Cu(In,Ga)Se{sub 2} solar cells with double layered buffers grown by chemical bath deposition

    Energy Technology Data Exchange (ETDEWEB)

    Li, Z.Q.; Shi, J.H.; Zhang, D.W.; Liu, Q.Q.; Sun, Z.; Chen, Y.W. [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, North Zhongshan Rd. 3663, Shanghai 200062 (China); Yang, Z. [Key Laboratory for Thin Film and Microfabrication of the Ministry of Education, Research Institute of Micro/Nano Science and Technology, Shanghai Jiao Tong University, Shanghai 200240 (China); Huang, S.M., E-mail: engp5591@yahoo.com [Engineering Research Center for Nanophotonics and Advanced Instrument, Ministry of Education, Department of Physics, East China Normal University, North Zhongshan Rd. 3663, Shanghai 200062 (China)

    2011-10-31

    In based mixture In{sub x}(OH,S){sub y} buffer layers deposited by chemical bath deposition technique are a viable alternative to the traditional cadmium sulfide buffer layer in thin film solar cells. We report on the results of manipulating the absorber/buffer interface between the chalcopyrite Cu(In,Ga)Se{sub 2} (CIGS) absorber and CdS or ZnS buffer by addition of a thin In based mixture layer. It is shown that the presence of thin In{sub x}(OH,S){sub y} at the CIGS absorber/CdS or ZnS buffer interfaces greatly improve the solar cell performances. The performances of CIGS cells using dual buffer layers composed of In{sub x}(OH,S){sub y}/CdS or In{sub x}(OH,S){sub y}/ZnS increased by 22.4% and 51.6%, as compared to the single and standard CdS or ZnS buffered cells, respectively.

  20. Environmental geochemistry of a Kuroko-type massive sulfide deposit at the abandoned Valzinco mine, Virginia, USA

    Science.gov (United States)

    Seal, R.R.; Hammarstrom, J.M.; Johnson, A.N.; Piatak, N.M.; Wandless, G.A.

    2008-01-01

    The abandoned Valzinco mine, which worked a steeply dipping Kuroko-type massive sulfide deposit in the Virginia Au-pyrite belt, contributed significant metal-laden acid-mine drainage to the Knight's Branch watershed. The host rocks were dominated by metamorphosed felsic volcanic rocks, which offered limited acid-neutralizing potential. The ores were dominated by pyrite, sphalerite, galena, and chalcopyrite, which represented significant acid-generating potential. Acid-base accounting and leaching studies of flotation tailings - the dominant mine waste at the site - indicated that they were acid generating and therefore, should have liberated significant quantities of metals to solution. Field studies of mine drainage from the site confirmed that mine drainage and the impacted stream waters had pH values from 1.1 to 6.4 and exceeded aquatic ecosystem toxicity limits for Fe, Al, Cd, Cu, Pb and Zn. Stable isotope studies of water, dissolved SO42 -, and primary and secondary sulfate and sulfide minerals indicated that two distinct sulfide oxidation pathways were operative at the site: one dominated by Fe(III) as the oxidant, and another by molecular O2 as the oxidant. Reaction-path modeling suggested that geochemical interactions between tailings and waters approached a steady state within about a year. Both leaching studies and geochemical reaction-path modeling provided reasonable predictions of the mine-drainage chemistry.

  1. Self-assembled synthesis of 3D Cu(In1 - xGax)Se2 nanoarrays by one-step electroless deposition into ordered AAO template

    Science.gov (United States)

    Zhang, Bin; Zhou, Tao; Zheng, Maojun; Xiong, Zuzhou; Zhu, Changqing; Li, Hong; Wang, Faze; Ma, Li; Shen, Wenzhong

    2014-07-01

    Quaternary nanostructured Cu(In1 - xGax)Se2 (CIGS) arrays were successfully fabricated via a novel and simple solution-based protocol on the electroless deposition method, using a flexible, highly ordered anodic aluminium oxide (AAO) substrate. This method does not require electric power, complicated sensitization processes, or complexing agents, but provides nearly 100% pore fill factor to AAO templates. The field emission scanning electron microscopy (FE-SEM) images show that we obtained uniformly three-dimensional nanostructured CIGS arrays, and we can tailor the diameter and wall thicknesses of the nanostructure by adjusting the pore diameter of the AAO and metal Mo layer. Their chemical composition was determined by energy-dispersive spectroscopy analysis, which is very close to the stoichiometric value. The Raman spectroscopy, x-ray diffraction (XRD) pattern, and transmission electron microscopy (TEM) further confirm the formation of nanostructured CIGS with prominent chalcopyrite structure. The nanostructured CIGS arrays can support the design of low-cost, highlight-trapping, and enhanced carrier collection nanostructured solar cells.

  2. Genesis of the Precambrian copper-rich Caraiba hypersthenite-norite complex, Brazil

    Science.gov (United States)

    Oliveira, E. P.; Tarney, J.

    1995-08-01

    Caraiba, the largest Brazilian copper deposit under exploitation, consists mostly of disseminated and remobilised bornite and chalcopyrite hosted in early Proterozoic norite and hypersthenite. The mafic igneous complex comprises multiple intrusions of dykes, veins and breccias of norites and hypersthenites, with minor proportions of amphibolised gabbronorite and peridotite xenoliths transported by the magma from deeper levels in the lithosphere. The country rocks are high-grade gneisses, granulites and metasediments. Compositions of plagioclase(An60-40) and orthopyroxene(En70-60) fall in a narrow range similar to the Koperberg Suite from the Okiep copper district, South Africa, and to that in many massif-type anorthosites. Whole-rock major and trace element geochemistry indicate a parental magma enriched in Fe, LREE, P, K, and Cu. Negative Nb anomalies on multi-element plots and fractionated REE patterns, along with sulphide sulphur isotopes in the range δ34S = -1.495 to + 0.643‰, suggest a primary mantle lithosphere source, although a lower crustal source for the gabbronorite and peridotite xenoliths cannot be excluded. Geochronological and field evidence indicate that both norite and hypersthenite are likely to have been emplaced during a major sinistral transcurrent (partly transpressional) shearing event associated with the waning stage of evolution of the early Proterozoic Salvador-Curaçá orogen.

  3. Mechanism of influence of ferric ion on electrogenerative leaching of sulfide minerals with FeCl3

    Institute of Scientific and Technical Information of China (English)

    WANG Shao-fen; FANG Zheng

    2006-01-01

    A dual cell system was used to study the influence of ferric ion on the electrogenerative leaching of sulfide minerals.Reaction mechanisms for the ferric chloride electrogenerative leaching of a series of sulfide minerals were proposed based on the data collected from the dual cell experiments. The influences of ferric ion on the electrogenerative leaching of sulfide minerals are similar. Ferric ion plays an important role on limiting the electrogenerative leaching rate at a relatively low concentration of FeCl3(about less than 0.15 mol/L). The mathematical models based on the Butler-Volmer relation were delineated, and kinetic equations with respect to ferric ions for each sulfide mineral were obtained. The kinetic equations show that when the concentration of ferric ion is relatively low, the electrogenerative leaching rates are predicted to be proportional to 6/7, 4/5, 2/3 and 2/3 order of ferric ion for nickel concentrate, chalcopyrite concentrate, sphalerite and galena respectively. As the concentration of ferric ion increase, the correlative dependence between electrogenerative leaching rate and concentration of ferric ion becomes weak. The above conclusions are in agreement with the experimental results.

  4. Ore Petrography Using Optical Image Analysis: Application to Zaruma-Portovelo Deposit (Ecuador

    Directory of Open Access Journals (Sweden)

    Edgar Berrezueta

    2016-06-01

    Full Text Available Optical image analysis (OIA supporting microscopic observation can be applied to improve ore mineral characterization of ore deposits, providing accurate and representative numerical support to petrographic studies, on the polished section scale. In this paper, we present an experimental application of an automated mineral quantification process on polished sections from Zaruma-Portovelo intermediate sulfidation epithermal deposit (Ecuador using multispectral and color images. Minerals under study were gold, sphalerite, chalcopyrite, galena, pyrite, pyrrhotite, bornite, hematite, chalcocite, pentlandite, covellite, tetrahedrite and native bismuth. The aim of the study was to quantify the ore minerals visible in polished section through OIA and, mainly, to show a detailed description of the methodology implemented. Automated ore identification and determination of geometric parameters predictive of geometallurgical behavior, such as grade, grain size or liberation, have been successfully performed. The results show that automated identification and quantification of ore mineral images are possible through multispectral and color image analysis. Therefore, the optical image analysis method could be a consistent automated mineralogical alternative to carry on detailed ore petrography.

  5. Microbial control of silver mineralization at a sea-floor hydrothermal site on the northern Gorda Ridge

    Science.gov (United States)

    Zierenberg, R.A.; Schiffman, P.

    1990-01-01

    THE Sea Cliff hydrothermal field, on the northern Gorda Ridge, contains mounds and chimneys of hydrothermally precipitated sulphide and sulphate minerals typical of sea-floor hydrothermal vent sites1. In addition, large areas of the sea floor are covered by subhorizontal hydrothermal crusts. Samples of the crust recovered by submersible are composed of intensely altered fragments of basalt and basaltic hyaloclastite cemented by amorphous silica and chalcedony with less abundant barite, and minor amounts of base-metal sulphide minerals2. Some surfaces of the crust were formerly colonized by bacterial mats, which are locally preserved by replacement and overgrowth of the bacterial filaments by metal sulphide minerals and amorphous silica. The bacterial filaments are selectively replaced by prousite (Ag3AsS3), pearceite3 (Ag14.7-XCu1.3+xAs2S11), chalcopyrite (CuFeS2) and rarely by galena (PbS). Our observations suggest that bacterially mediated processes selectively precipitate silver, arsenic and copper, and that biological processes may contribute to precious-metal enrichment in some sea-floor hydrothermal base-metal sulphide deposits.

  6. ARTICLES: Metal Precursor Influence on Performance of Culn1-xGaxSe2 Films

    Science.gov (United States)

    Wang, Man; Zhang, Zhong-wei; Jiang, Guo-shun; Zhu, Chang-fei

    2010-06-01

    CuIn1-xGaxSe2 (CIGS) films were prepared by a two-stage method, in which Cu-In-Ga metallic precursors were firstly deposited on unheated Mo-coated soda lime glass substrates by direct current sputtering CuGa (20%Ga) and radio frequency sputtering In targets in an Ar atmosphere, followed by selenization at 520 °C for 40 min in Se vapor. By adjusting the sputtering thickness ratio of surface CuGa (20%Ga) and bottom CuGa (20%Ga) alloy layers in metal precursor, different CIGS thin films were fabricated. Through X-ray diffraction spectra, Raman spectra, local energy dispersive spectrometer, planar- and cross-sectional views of scanning electron microscopy measurements, it revealed that the CIGS thin films from selenization of metal precursor with CuGa:In:CuGa thickness ratio of 7:20:3 (sample-2-se) was of chalcopyrite structure with the preferred (112) orientation, and the grains sizes ranged from 0.5 μm to 2 μm, and sample-2-se had no binary compound phase of In-Se and order defect compound phase. Consequently, the results of illuminated current-voltage curve and quantum efficiency measurements showed that the CIGS film device made from sample-2-se had relative higher photo-electric conversion efficiency (3.59%) and good spectrum response.

  7. Characterization of CdS Thin-Film in High Efficient CdS/CdTe Solar Cells

    Science.gov (United States)

    Tsuji, Miwa; Aramoto, Tetsuya; Ohyama, Hideaki; Hibino, Takeshi; Omura, Kuniyoshi

    2000-07-01

    Cadmium sulfide (CdS) thin films are the most commonly used window materials for high efficient cadmium telluride (CdTe) and chalcopyrite polycrystalline thin-film photovoltaic devices. High efficient CdS/CdTe solar cells with thin CdS films have been developed using ultrathin CdS films with a thickness of less than 0.1 μm. CdS films were deposited on transparent conductive oxide (TCO)/glass substrates by the metal organic chemical vapor deposition (MOCVD) technique. CdTe films were subsequently deposited by the close-spaced sublimation (CSS) technique. The screen printing and sintering method fabricated carbon and silver electrodes. Cell performance depends primarily on the electrical and optical properties of CdS films. Therefore we started to develop higher-quality CdS films and found clear differences between high- and low-quality CdS films from the analyses of scanning electron microscope (SEM), atomic force microscope (AFM), secondary ion mass spectroscopy (SIMS), thermal desorption spectrometry (TDS) and Fourier transforms-infrared spectrometry (FT-IR) measurements. As a result of controlling the quality of CdS films, a photovoltaic conversion efficiency of 10.5% has been achieved for size of 1376 cm2 of the solar cells under the Air Mass (AM) 1.5 conditions of the Japan Quality Assurance Organization.

  8. Mineralogical analysis of auriferous ores from the El Diamante mine, Colombia

    Energy Technology Data Exchange (ETDEWEB)

    Bustos Rodriguez, Humberto, E-mail: hbustos@ut.edu.co; Oyola Lozano, Dagoberto; Rojas Martinez, Yebrayl A. [Universidad del Tolima, Departamento de Fisica (Colombia); Perez Alcazar, German A. [Universidad del Valle, Departamento de Fisica (Colombia); Flege, Stefan; Balogh, Adam G. [Darmstadt University of Technology, Institute of Materials Science (Germany); Cabri, Louis J. [Cabri Consulting Inc. (Canada); Tubrett, Michael [Memorial University of Newfoundland (Canada)

    2007-02-15

    X-ray diffraction (XRD), Moessbauer spectrometry (MS), secondary ions mass spectroscopy (SIMS) and laser-ablation microprobe-inductively coupled plasma-mass spectrometry (LAM-ICP-MS) were used to study mineral samples of Colombian auriferous ores collected from the 'El Diamante' mine, located in the municipality of Guachavez-Narino, in Colombia. The samples were prepared as polished thin sections and polished sections. From XRD data, quartz, sphalerite and pyrite were detected and their respective cell parameters were estimated. From MS analyses, pyrite, arsenopyrite and chalcopyrite were identified; their respective hyperfine parameters and respective texture were deduced. Multiple regions of approximately 200 x 200 {mu}m in each sample were analyzed with SIMS; the occurrence of 'invisible gold' associated mainly with pyrite and secondarily with arsenopyrite could thus be assigned. It was also found that pyrite is of the arsenious type. Spots from 30 to 40 {mu}m in diameter were analyzed with LAM-ICP-MS for pyrite, arsenopyrite and sphalerite; Au is 'homogeneously' distributed inside the structure of the arsenious pyrite and the arsenopyrite (not as inclusions); the chemical composition indicates similarities of this 'invisible gold', forming a solid solution with arsenious pyrite and arsenopyrite. One hundred nineteen and 62 ppm of 'invisible gold' was quantified in 21 spots analyzed on pyrite and in 14 spots on arsenopyrite, respectively.

  9. Structural, photoelectrical characterization of Cu(InAl)Se2 thin films and the fabrication of Cu(InAl)Se2 based solar cells

    Science.gov (United States)

    Kavitha, B.; Dhanam, M.

    2013-01-01

    Films of Cu(InAl)Se2 were deposited onto glass substrates by SILAR (successive ionic layer adsorption and reaction) method. All the deposited films were found to be polycrystalline in nature exhibiting the chalcopyrite structure with the crystallite orientation along (112), (220/204) and (116/312) directions. The photocurrent was found to increase with increase in film thickness and also with increase of light intensity. Photocurrent spectra showed a peak related to the band-to-band transition. The spectral response of Cu(InAl)Se2 thin films was studied by allowing the radiation to pass through a series of interference filters in the wavelength range 300 to 1200 nm. Films of higher thickness exhibited higher photosensitivity while lower thickness films exhibited moderate photosensitivity. Cu(InAl)Se2-based solar cells with different types of buffer layers such as CdS, CdS:Cu, CdS:In were fabricated. The current and voltage were measured using an optical power meter and an electrometer and the fabricated solar cells were illuminated using 100 mW/cm2 white light under AM1 conditions.

  10. Effect of [Cu]/[In] ratio on properties of CuInS 2 thin films prepared by successive ionic layer absorption and reaction method

    Science.gov (United States)

    Shi, Yong; Jin, Zhengguo; Li, Chunyan; An, Hesong; Qiu, Jijun

    2006-03-01

    CuInS 2 ternary films were prepared by a soft solution processing, i.e. successive ionic layer absorption and reaction (SILAR) method. The films were deposited on glass substrates at room temperature and heat-treated under Ar atmosphere at 500 °C for 1 h. CuCl 2 and InCl 3 mixed solutions with different ionic ratios ([Cu]/[In]) were used as cation precursor and Na 2S as the anion precursor. The effect of the [Cu]/[In] ratio in precursor solution on the structural, chemical stoichiometry, topographical, optical and electrical properties of CuInS 2 thin films was investigated. XPS results demonstrated that stoichiometric CuInS 2 film can be obtained by adjusting [Cu]/[In] ratios in solution. Chalcopyrite structure of the film was confirmed by XRD analysis. The near stoichiometric CuInS 2 film has the optical band gap Eg of 1.45 and resistivity decreased with increase of [Cu]/[In] ratios.

  11. Daughter minerals in fluid inclusions of garnet and diopside from Tongguanshan Copper Deposit by SEM/EDS and LRM

    Institute of Scientific and Technical Information of China (English)

    Yuling Xie; Jiuhua Xu; Zengqian Hou; Zhusen Yang; Wenyi Xu; Yifeng Meng; Baohua Wang

    2004-01-01

    Tongguanshan copper deposit of Tongling large ore belt is one of the typical skarn copper deposits. Based on careful observation under microscope many daughter minerals including transparent ones and opaque ones have been distinguished in the fluid inclusions of garnet and diopside. The results of SEM/EDS (scanning electron microscope/energy dispersive spectrometer) and LRM (laser Raman microprobe) analysis show that these daughter minerals in garnet are sylvite, halite, sphalerite, chalcopyrite and carbonate. Sylvite daughter mineral is very popular in garnet and diopside. The existence of so much sylvite daughter mineral and other daughter minerals in the fluid inclusions indicates that the ore-forming fluid is of supper-high salinity and high potassium concentration. High potassium concentration in the fluid inclusions agrees with K-rich mesotype-acid rock and K-silicate alteration that occurred widely in this area. The daughter mineral assemblage in garnet and diopside is similar to the mineral assemblage of oreforming stage that followed skarn stage.

  12. Santaclaraite, a new calcium-manganese silicate hydrate from California.

    Science.gov (United States)

    Erd, Richard C.; Ohashi, Y.

    1984-01-01

    Santaclaraite, ideally CaMn4(Si5O14(OH))(OH).H2O, occurs as pink and tan veins and masses in Franciscan chert in the Diablo Range, Santa Clara and Stanislaus counties, California. It is associated with four unidentified Mn silicates, Mn-howieite, quartz, braunite, calcite, rhodochrosite, kutnahorite, baryte, harmotome, chalcopyrite and native copper. Santaclaraite is triclinic, space group B1, a 15.633(1), b 7.603(1) , c 12.003(1) A, alpha 109.71(1)o, beta 88.61(1)o, gamma 99.95(1) o, V 1322.0(3) A3; Z = 4. The strongest lines of the X-ray pattern are 7.04(100), 3.003(84), 3.152(80), 7.69(63), 3.847(57) A. Crystals are lamellar to prismatic (flattened on (100)), with good cleavage on (100) and (010); H. 61/2 Dcalc. 3.398 g/cm3, Dmeas. 3.31 (+ or -0.01); optically biaxial negative, alpha 1.681, beta 1.696, gamma 1.708 (all + or - 0.002), 2Valpha 83 (+ or -1)o. Although chemically a hydrated rhodonite, santaclaraite dehydrates to Mn-bustamite at approx 550oC (in air) . Santaclaraite is a five-tetrahedral-repeat single-chain silicate and has structural affinities with rhodonite, nambulite, marsturite, babingtonite and inesite.-J.A.Z.

  13. Occurrence mechanism of silicate and aluminosilicate minerals in Sarcheshmeh copper flotation concentrate

    Institute of Scientific and Technical Information of China (English)

    H.R. Barkhordari; E. Jorjani; A. Eslami; M. Noaparast

    2009-01-01

    The Sarcheshmeh copper flotation circuit is producing 5×10~4 t copper concentrate per month with an averaging grade of 28% Cu in rougher, cleaner and reeleaner stages. In recent years, with the increase in the open pit depth, the content of aluminosili- cate minerals increased in plant feed and subsequently in flotation concentrate. It can motivate some problems, such as unwanted consumption of reagents, decreasing of the copper concentrate grade, increasing of Al_2O_3 and SiO_2 in the copper concentrate, and needing a higher temperature in the smelting process. The evaluation of the composite samples related to the most critical working period of the plant shows that quartz, illite, biotite, chlorite, orthoclase, albeit, muscovite, and kaolinite are the major Al_2O_3 and SiO_2 beating minerals that accompany chalcopyrite, chalcoeite, and covellite minerals in the plant feed. The severe alteration to clay min-erals was a general rule in all thin sections that were prepared from the plant feed. Sieve analysis of the flotation concentrate shows that Al_2O_3 and SiO_2 bearing minerals in the flotation concentrate can be decreased by promoting the size reduction from 53 to 38 μm. Interlocking of the Al_2O_3 and SiO_2 beating minerals with ehalcopyrite and ehalcocite is the occurrence mechanism of silicate and aluminosilicate minerals in the flotation concentrate. The dispersed form of interlocking is predominant.

  14. Mineralogical Study of a Biologically-Based Treatment System That Removes Arsenic, Zinc and Copper from Landfill Leachate

    Directory of Open Access Journals (Sweden)

    Maryam Khoshnoodi

    2013-12-01

    Full Text Available Mineralogical characterization by X-ray diffraction (XRD and a high throughput automated quantitative evaluation of minerals by scanning electron microscopy (QEMSCAN was conducted on samples from a sulphate-reducing biochemical reactor (BCR treating high concentrations of metals (As, Zn, Cu in smelter waste landfill seepage. The samples were also subjected to energy dispersive X-ray (EDX analysis of specific particles. The bulk analysis results revealed that the samples consisted mainly of silicate and carbonate minerals. More detailed phase analysis indicated four different classes: zinc-arsenic sulphosalts/sulphates, zinc-arsenic oxides, zinc phosphates and zinc-lead sulphosalts/sulphates. This suggests that sulphates and sulphides are the predominant types of Zn and As minerals formed in the BCR. Sphalerite (ZnS was a common mineral observed in many of the samples. In addition, X-ray point analysis showed evidence of As and Zn coating around feldspar and amphibole particles. The presence of arsenic-zinc-iron, with or without cadmium particles, indicated arsenopyrite minerals. Copper-iron-sulphide particles suggested chalcopyrite (CuFeS2 and tennantite (Cu,Fe12As4S13. Microbial communities found in each sample were correlated with metal content to describe taxonomic groups associated with high-metal samples. The research results highlight mineral grains that were present or formed at the site that might be the predominant forms of immobilized arsenic, zinc and copper.

  15. Characterization of CuInS2 thin films prepared by sulfurization of Cu-In precursor

    Institute of Scientific and Technical Information of China (English)

    YAN You-hua; LIU Ying-chun; FANG Ling; ZHU Jing-sen; ZHAO Hai-hua; LI De-ren; LU Zhi-chao; ZHOU Shao-xiong

    2008-01-01

    CuInS2 thin films were prepared by sulfurization of Cu-In precursors. The influences of the deposition sequence of Cu and In layers, such as Cu/In, Cu/In/In, and In/Cu/In, on structure, topography, and optical properties of CuInS2 thin films were investigated. X-ray diffraction results show that the deposition sequence of Cu and In layers affects the crystalline quality of CuInS2 films. Atomic force microstructure images reveal that the grain size and surface roughness are related to the deposition sequence used. When the deposition sequence of precursor is In/Cu/In, the CuInS2 thin films show a single-phase chalcopyrite structure with (112) preferred orientation. The surface morphology of CIS films is uniform and compacted. The absorption coefficient is larger than 104cm-1 with optical band gap Eg close to 1.4 eV.

  16. Preparation of CulnSe2 thin films by paste coating

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    Precursor pastes were obtained by milling Cu-In alloys and Se powders.CuInSe2 thin films were successfully prepared by precursor layers,which were coated using these pastes,and were annealed in a H2 atmosphere.The pastes were tested by laser particle diameter analyzer,simultaneous thermogravimetric and differential thermal analysis instruments (TG-DTA),and X-ray diffractometry (XRD).Selenized films were characterized by XRD,scanning electron microscopy (SEM),and energy dispersive spectroscopy (EDS).The results indicate that chalcopyrite CuInSe2 is formed at 180℃ and the crystallinity of this phase is improved as the temperature rises.All the CuInSe2 thin films,which were annealed at various temperatures,exhibit the preferred orientation along the (112) plane.The compression of precursor layers before selenization step is one oftbe most essential factors for the preparation of perfect CulnSe2 thin films.

  17. Direct Production of Copper

    Science.gov (United States)

    Victorovich, G. S.; Bell, M. C.; Diaz, C. M.; Bell, J. A. E.

    1987-09-01

    The use of commercially pure oxygen in flash smelting a typical chalcopyrite concentrate or a low grade comminuted matte directly to copper produces a large excess of heat. The heat balance is controlled by adjusting the calorific value of the solid feed. A portion of the sulfide material is roasted to produce a calcine which is blended with unroasted material, and the blend is then autogeneously smelted with oxygen and flux directly to copper. Either iron silicate or iron calcareous slags are produced, both being subject to a slag cleaning treatment. Practically all of the sulfur is contained in a continuous stream of SO2 gas, most of which is strong enough for liquefaction. A particularly attractive feature of these technologies is that no radically new metallurgical equipment needs to be developed. The oxygen smelting can be carried out not only in the Inco type flash furnace but in other suitable smelters such as cyclone furnaces. Another major advantage stems from abolishion of the ever-troublesome converter aisle, which is replaced with continuous roasting of a fraction of the copper sulfide feed.

  18. Mineralogical, textural, structural and geochemical aspects of Nakhlak lead mine, Isfahan

    Directory of Open Access Journals (Sweden)

    Mohammad Ali Jazi

    2010-11-01

    Full Text Available Nakhlak lead mine is located at the Nakhlak mountain 55 km NE of Anarak town in Isfahan province. The mineralogy is simple; galena and barite are the main primary minerals and cerussite is the main secondary mineral. Sphalerite, pyrite, chalcopyrite, tetrahedrite-tennantite and acanthite occur as minor and trace mineral inclusions in galena. Secondary minerals are anglesite, plattnerite, wulfenite and malachite. The host rock has undergone a pre-mineralization dolomitization process. Four types of dolomite have been identified which saddle dolomite is the most distinguished. Open space filling textures occur in the form of breccia, cockade, crustification and colloform. Analysis of the galena samples indicates presence of many trace elements in galena among which silver is the most important. Element pairs such as Ag-As, Zn-Cd, As-Cu and As-Sb are highly correlated. This correlation may be explained by the presence of inclusions. Ag-Sb-Bi ternary diagram indicates that galena samples from Nakhlak are rich in Ag and Sb and poor in Bi. Sb/Bi (3773 ratio in galena is suggestive of a low temperature of formation for the deposit. The Upper Cretaceous carbonate host rocks and their dolomitization, the stratabound and epigenetic mineralization, the absence of igneous activity, the open space filling texture, the simple mineralogy and geochemistry all point to a Mississippi valley type model for the Nakhlak Pb deposit.

  19. Characterization of gold mineralization in Garin Hawal area, Kebbi State, NW Nigeria, using remote sensing

    Directory of Open Access Journals (Sweden)

    Talaat M. Ramadan

    2010-12-01

    Full Text Available Garin Hawal area, Kebbi State, NW Nigeria is part of the Neoproterozoic to Early Phanerozoic terrane separating the west African and Congo Cratons. Three main gold-bearing shear zones were detected in the study area from the processed Landsat ETM+ images and extensive ground investigation. Field and petrographical studies indicate that the Neoproterozoic rocks are represented by a highly folded and faulted belt constituted of hornblende, muscovite and graphite schist. They are intruded by granondiorites and late to post granitic dykes. Extensive alteration zones were identified using high resolution QuickBird image along Garin Hawal shear zone. The alteration zones and associated quartz veins are generally concordant with the main NE–SW regional structural trend and are dipping to the NW. Geochemical studies indicate that the gold content reaches 8 g/t in the alteration zones, while it reaches up to 35 g/t in the quartz veins. Mineralogical studies indicate that the alterations are strongly potassium-enriched. Pyrophyllite, kaolinite, illite, gypsum and quartz also occur. The main ore minerals are gold, chalcopyrite, arsenopyrite, pyrite, galena and iron oxides. This study indicates that the alteration zones and the associated quartz veins in the muscovite schist are promising and need more detailed exploration for Au and Ag mineralization to evaluate their potential.

  20. Photoluminescence of CuInSe2 and its intrinsic defect states

    Science.gov (United States)

    Abou-Elfotouh, F.; Dunlavy, D. J.; Kazmerski, L. L.; Alkuhaimi, S.; Moustafa, R.

    Photoluminescence emission spectra of CuInSe2 crystals with various molecularity and stoichiometry deviations are investigated before and after heat treatments in air at temperatures between 200 and 400 C. Compositional depth profiles of Cd/CuInSe2 heterojunctions heated at 200-250 C indicate that In and Cu outdiffusion takes place at the interface. On the basis of the photoluminescence (PL) spectra and the expected intrinsic defects in the chalcopyrite CuInSe2, energy band diagrams have been proposed to identify the active intrinsic defects in CuInSe2 and to determine their energy location. Accordingly, In-rich material has two acceptor states due to VCu and Sei defects, and three donors due to InCu, Ini and VSe. The origins of the two acceptor states in the Cu-rich material are VIn and CuIn, while donors are attributed to Cui and VSe defects. The PL data are utilized to define the electrically active defects in an effort to correlate the cell performance with the intrinsic defect state behavior. It is deduced that annealing at 200 C improves the cell performance by increasing the net concentration of the acceptor states in the CuInSe2 base, contributing to a conductivity type-conversion of n-type material. A net excess of donors is created due to heat treatments at temperatures above 250 C, correlating with a deterioration of cell performance.

  1. Optical properties and defect levels in a surface layer found on CuInSe{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Abulfotuh, F.; Wangensteen, T.; Ahrenkiel, R.; Kazmerski, L.L. [National Renewable Energy Lab., Golden, CO (United States)

    1996-09-01

    In this paper the authors have used photoluminescence (PL) and wavelength scanning ellipsometry (WSE) to clarify the relationship among the electro-optical properties of copper indium diselenide (CIS) thin films, the type and origin of dominant defect states, and device performance. The PL study has revealed several shallow acceptor and donor levels dominating the semiconductor. PL emission from points at different depths from the surface of the CIS sample has been obtained by changing the angle of incidence of the excitation laser beam. The resulting data were used to determine the dominant defect states as a function of composition gradient at the surface of the chalcopyrite compound. The significance of this type of measurement is that it allowed the detection of a very thin layer with a larger bandgap (1.15--1.26 eV) than the CIS present on the surface of the CIS thin films. The presence of this layer has been correlated by several groups to improve the CIS cell performance. An important need that results from detecting this layer on the surface of the CIS semiconductor is the determination of its thickness and optical constants (n, k) as a function of wavelength. The thickness of this surface layer is about 500 {angstrom}.

  2. Precambrian crustal evolution and Cretaceous–Palaeogene faulting in West Greenland: A lead isotope study of an Archaean gold prospect in the Attu region, Nagssugtoqidian orogen, West Greenland

    Directory of Open Access Journals (Sweden)

    Stendal, Henrik

    2006-12-01

    Full Text Available This paper presents a lead isotope investigation of a gold prospect south of the village Attu in the northern part of the Nagssugtoqidian orogen in central West Greenland. The Attu gold prospect is a replacement gold occurrence, related to a shear/mylonite zone along a contact between orthogneissand amphibolite within the Nagssugtoqidian orogenic belt. The mineral occurrence is small, less than 0.5 m wide, and can be followed along strike for several hundred metres. The mineral assemblage is pyrite, chalcopyrite, magnetite and gold. The host rocks to the gold prospect are granulite facies ‘brown gneisses’ and amphibolites. Pb-isotopic data on magnetite from the host rocks yield an isochron in a 207Pb/204Pb vs. 206Pb/204Pb diagram, giving a date of 3162 ± 43 Ma (MSWD = 0.5. This date is interpreted to represent the age of the rocks in question, and is older than dates obtained from rocks elsewhere within the Nagssugtoqidian orogen. Pb-isotopic data on cataclastic magnetite from the shear zone lie close to this isochron, indicating a similar origin. The Pb-isotopic compositions of the ore minerals are similar to those previously obtained from the close-by ~2650 Ma Rifkol granite, and suggest a genetic link between the emplacement of this granite and the formation of the ore minerals in the shear/mylonite zone. Consequently, the age of the gold mineralisation is interpreted tobe late Archaean.

  3. Sulfide-melt inclusions in mantle xenoliths from the Changbaishan district, Jilin province, China%中国吉林长白山地区地幔捕虏体中硫化物熔体包裹体

    Institute of Scientific and Technical Information of China (English)

    徐九华; 谢玉玲

    2007-01-01

    Mantle xenoliths are common in the Cenozoic basalts of the Changbaishan District, Jilin Province, China. Sulfide assemblages in mantle minerals can be divided into three types: isolated sulfide grains, sulfide-melt inclusions and filling sulfides in fractures. Sulfide-melt inclusions occur as single-phase sulfides, sulfide-silicate melt, and CO2-sulfide-silicate melt inclusions.Isolated sulfide grains are mainly composed of pyrrhotite, but cubanite was found occasionally. Sulfide-melt inclusions are mainly composed of pentlandite and MSS, with small amounts of chalcopyrite and talnakhite. The calculated distribution coefficient KD3 for lherzolite are similar to that of mean experimental value. The bulk sulfides in lherzolite were in equilibrium with the enclosing minerals, indicating immiscible sulfide melts captured in partial melting of upper mantle. Sulfide in fractures has higher Ni/Fe and ( Fe + Ni)/Sthan those of sulfide melt inclusions. They might represent later metasomatizing fluids in the mantle. Ni/Fe and ( Fe + Ni)/S increase from isolated grains, sulfide inclusions to sulfides in fractures. These changes were not only affected by temperature and pressure, but by geochemistry of Ni, Fe and Cu, and sulfur fugacity as well.

  4. Geological and geochemical characteristics of the Aksug porphyry Cu-Mo system, Altay-Sayan region, Russia%俄罗斯阿尔泰-Sayan地区Aksug斑岩Cu-Mo体系的地质与地球化学特征

    Institute of Scientific and Technical Information of China (English)

    Berzina AN; Berzina AP

    2008-01-01

    The Aksug deposit, located in Ahay-Sayan region of Russia, is one of the largest porphyry Cu-Mo deposits in Southern Siberia. The ore-bearing porphyries of the Aksug porphyry Cu-Mo system were formed in post-collisional environment. Geochemically they belong to calk-alkaline and high K-calk-alkaline series. Rocks are characterized by enrichment of LILE and depletion of HSFE and HREE, showing the importance of subduction-related components in magma generation. Large plutonic intrusions that host porphyry systems have been formed during collision. The origin of porphyritic rocks is dominantly the mantle with lower crustal contribution. The mainly economically important Cu-Mo mineralization is closely related to a porphyry series in time and space, being emplaced towards the end of magmatic activity. Though the emplacement of plutonic and ore-bearing porphyry complexes took place in different geodynamic environments, both complexes are characterized by certain similarity in geochemical composition, alkalinity, trace element content, Sr isotopic composition. This fact evidently indicates a common deep-seated magmatic source (at the lower crust-upper mantle level), Low initial 87Sr/86Sr, sulfur isotopic characteristics and presence of PGE-Co-Ni mineralization in associated pyrite-chalcopyrite ores suggest that mantle source of chalcophile elements was of high importance in porphyry Cu-Mo mineralization of the Aksug deposit.

  5. A field technique for rapid lithological discrimination and ore mineral identification: Results from Mamandur Polymetal Deposit, India

    Indian Academy of Sciences (India)

    D Ramakrishnan; M Nithya; K D Singh; Rishikesh Bharti

    2013-02-01

    This work illustrates the efficiency of field spectroscopy for rapid identification of minerals in ore body, alteration zone and host rocks. The adopted procedure involves collection of field spectra, their processing for noise, spectral matching and spectral un-mixing with selected library end-members. Average weighted spectral similarity and effective peak matching techniques were used to draw end-members from library. Constrained linear mixture modelling technique was used to convolve end-member spectra. Linear mixture model was optimized based on root mean square error between field- and modelled-spectra. Estimated minerals and their abundances were subsequently compared with conventional procedures such as petrography, X-ray diffraction and X-ray fluorescence for accuracy assessment. The mineralized zone is found to contain azurite, galena, chalcopyrite, bornite, molybdenite, marcacite, gahnite, hematite, goethite, anglesite and malachite. The alteration zone contains chlorite, kaolinite, actinolite and mica. These mineral assemblages correlate well with the petrographic measurements (2 = 0.89). Subsequently, the bulk chemistry of field samples was compared with spectroscopically derived cumulative weighted mineral chemistry and found to correlate well (2 = 0.91–0.98) at excellent statistical significance levels (90–99%). From this study, it is evident that field spectroscopy can be effectively used for rapid mineral identification and abundance estimation.

  6. Green Synthesis of CuInS2/ZnS Nanocrystals with High Photoluminescence and Stability

    Directory of Open Access Journals (Sweden)

    Min Fu

    2015-01-01

    Full Text Available Highly photoluminescent core/shell CuInS2/ZnS (CIS/ZnS nanocrystals were synthesized. Zinc acetate and dodecanethiol in octadecene solvent were used for shell growth. The structure and composition of QDs were investigated with inductively coupled plasma-optical emission spectroscopy, X-ray photoelectron spectroscopy, and transmission electron microscopy. The crystal phase of CIS was tetragonal chalcopyrite. Based on X-ray diffraction analysis, it has been concluded that the growth of the ZnS shell did not affect the phase structure of CuInS2 (CIS. Photoluminescence (PL quantum yield (QY of CIS increased to 80% after epitaxial growth of ZnS, and the PL emission wavelength can be feasibly tuned to be in the range of 560–710 nm by adjusting shell growth time. The superb photostability with high PL QY of CIS/ZnS nanocrystals is ascribed to the gradient of the chemical composition that has been formed between the core and the shell.

  7. Synthesis and optical properties of CuInS{sub 2} thin films prepared by sulfurization of electrodeposited Cu-In layers

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Yu-Cheng; Wu, Po-Feng [Program in Electrical and Communications Engineering, Feng Chia University, Seatwen, Taichung (China); Shi, Jen-Bin; Chen, Chih-Jung; Yang, Shui-Yuang [Department of Electronic Engineering, Feng Chia University, Seatwen, Taichung (China)

    2012-09-15

    The chalcopyrite CuInS{sub 2} thin film was fabricated at 500 C for 2 h by sulfurization of Cu-In layers (as precursors) that were sulfurized in a glass tube with pure sulfur powder. The structural, morphological, and optical properties of CuInS{sub 2} thin films are characterized using X-ray diffraction (XRD), field-emission scanning electron microscope (FE-SEM), and UV/Visible/NIR spectrophotometer. The study of UV/Visible/NIR absorption shows the band gap energy value of CuInS{sub 2} thin films is 1.5 eV. The XRD pattern shows the film is pure CuInS{sub 2}; no other peaks, such as CuS or CuIn{sub 5}S{sub 8} were observed. Furthermore, the surface of the CuInS{sub 2} film is compact characterized by FE-SEM, which also shows the disappearance of CuS on the surface at 500 C. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  8. Crystal and phonon structure of ZnSiP{sub 2}, a II-IV-V{sub 2} semiconducting compound

    Energy Technology Data Exchange (ETDEWEB)

    Pena-Pedraza, H., E-mail: heribertopp@ula.ve [Departamento de Fisica, Universidad de Pamplona, Pamplona 54518000 (Colombia); Lopez-Rivera, S.A.; Martin, J.M. [Laboratorio de Fisica Aplicada, ULA, Merida 5101 (Venezuela, Bolivarian Republic of); Delgado, J.M. [Laboratorio de Cristalografia, ULA, Merida 5101 (Venezuela, Bolivarian Republic of); Power, Ch. [Centro de Estudios en Semiconductores, ULA, Merida 5101 (Venezuela, Bolivarian Republic of)

    2012-09-20

    Using single-crystal X-ray diffraction and Raman spectroscopy, the characterization of a member of the II-IV-V{sub 2} family of semiconducting compounds, ZnSiP{sub 2}, is presented in this work. The diffraction experiment showed that ZnSiP{sub 2} crystallizes in a chalcopyrite-type of structure (space group: I4{sup Macron }2d) with unit cell parameters a = 5.407(9) Angstrom-Sign and c = 10.454(2) Angstrom-Sign . The structure is based on a cubic close-packed arrangement of phosphorus atoms with the two cations in an orderly way occupying one-half of the tetrahedral sites. In this structure, two Zn and two Si are bonded to each phosphorus atom and four phosphorus atoms are bonded to each cation. The results obtained are consistent with previous reports. Raman spectroscopy, Group Theory, and a modified correlation method allowed the assignment of the characteristics of the thirteen first-order Raman active optical vibrational modes observed for this material.

  9. Self-assembled synthesis of 3D Cu(In(1-x)Ga(x))Se2 nanoarrays by one-step electroless deposition into ordered AAO template.

    Science.gov (United States)

    Zhang, Bin; Zhou, Tao; Zheng, Maojun; Xiong, Zuzhou; Zhu, Changqing; Li, Hong; Wang, Faze; Ma, Li; Shen, Wenzhong

    2014-07-25

    Quaternary nanostructured Cu(In1 - xGax)Se2 (CIGS) arrays were successfully fabricated via a novel and simple solution-based protocol on the electroless deposition method, using a flexible, highly ordered anodic aluminium oxide (AAO) substrate. This method does not require electric power, complicated sensitization processes, or complexing agents, but provides nearly 100% pore fill factor to AAO templates. The field emission scanning electron microscopy (FE-SEM) images show that we obtained uniformly three-dimensional nanostructured CIGS arrays, and we can tailor the diameter and wall thicknesses of the nanostructure by adjusting the pore diameter of the AAO and metal Mo layer. Their chemical composition was determined by energy-dispersive spectroscopy analysis, which is very close to the stoichiometric value. The Raman spectroscopy, x-ray diffraction (XRD) pattern, and transmission electron microscopy (TEM) further confirm the formation of nanostructured CIGS with prominent chalcopyrite structure. The nanostructured CIGS arrays can support the design of low-cost, highlight-trapping, and enhanced carrier collection nanostructured solar cells.

  10. The formation of auriferous quartz-sulfide veins in the Pataz region, northern Peru: A synthesis of geological, mineralogical, and geochemical data

    Science.gov (United States)

    Schreiber, D. W.; Amstutz, G. C.; Fontboté, L.

    1990-12-01

    The Pataz region in the eastern part of the North Peruvian Department La Libertad hosts a number of important gold mining districts like La Lima, El Tingo, Pataz, Parcoy, and Buldibuyo. Economic gold mineralization occurs in quartz-sulfide veins at the margin of the calc-alkaline Pataz Batholith, that mainly consists of granites, granodiorites, and monzodiorites. The batholith is of Paleozoic age and cuts the Precambrian to Early Paleozoic low-grade metamorphic basement series. Its intrusion was controlled by a NNW-trending fault of regional importance. The gold-bearing veins are characterized by a two-stage sulfide mineralization. Bodies of massive pyrite and some arsenopyrite were formed in stage 1, and after subsequent fracturing they served as sites for deposition of gold, electrum, galena, sphalerite, and chalcopyrite. It is concluded that gold was transported as a AuCl{2/-}-complex by oxidizing chloride solutions and deposited near older pyrite by micro-scale redox changes and a slight temperature decrease. Mineralogical, textural, geochemical, and microthermometric features are interpreted as a consequence of mineralization at considerable depth produced by a hydrothermal system linked with the emplacement of the Pataz Batholith. acteristics in order to outline a general physicochemical model of the hydrothermal ore-forming processes.

  11. Mechanical properties and Raman scattering investigation under indentation of CdGa2S4 and CdGa2Se4

    Science.gov (United States)

    Shikimaka, O.; Burlacu, A.; Grabco, D.; Parvan, V.; Pyrtsac, C.; Ursaki, V.

    2016-05-01

    The behavior of CdGa2S4 and CdGa2Se4 single crystalline semiconductors under Berkovich indentation of the (1 1 2) face in the load range of 10-700 mN has been investigated. Values of hardness and Young’s modulus have been determined for this load range. A comparative analysis of crack development under indentation was performed for these two compounds. The observed indentation size effect was analyzed from the point of view of energy consumed for the formation of the residual imprint, fracture and relaxation processes. It was found that crack development affects the energy-load and hardness-load dependences, which show specific features for each compound. The effect of indentation on eventual phase transitions was investigated by comparing the micro-Raman spectra from a non-indented site with those measured in the indentation. Evidence of a phase transition under indentation from the initial defect chalcopyrite structure to a disordered zincblende phase is found.

  12. S掺杂CuInSe2:导致的体积变化对其禁带宽度的影响%Impact of Lattice Volume on the Band Gap Broadening of Isovalent S-Doped CuInSe2

    Institute of Scientific and Technical Information of China (English)

    陈翔; 赵宇军; 姚若河; 何巨龙

    2008-01-01

    运用第一性原理方法研究了CulnSe2和不同量的S掺杂CulnSe2所形成的化合物的电子结构.理论计算表明,S掺杂导致CuInse2禁带宽度增大,且通过对其电子结构和键长的分析,发现因S掺杂浓度的增加而导致的CulnSeS化合物晶格体积减小对其禁带宽度的增加有重要的影响.%The electronic structure of pure and S-doped chalcopyrite CulnSe2 is investigated using a first-principles pseudopotential method in the generalized gradient approximation. The calculation indicates that the band gap of CulnSe2 broadens as S-doping concentration increases. We find that the decreased lattice volume due to isovalent S-doping in CulnSe2 has a significant impact on the band gap broadening phenomena. This physical insight is further discussed with the study of the electronic structure and bond length changes.

  13. Systematic sulfur stable isotope and fluid inclusion studies on veinlet groups in the Sarcheshmeh porphyry copper deposit: based on new data

    Directory of Open Access Journals (Sweden)

    Mohammad Maanijou

    2012-10-01

    Full Text Available Mineralization occurred by intrusion of granodioritic stock of middle Miocene in volcano–sedimenrary rocks in Sarcheshmeh of early Tertiary age. This research is based on samples of new drilled boreholes and benches of 2500m elevation. Based on mineralogy and crosscutting relationships, at least four groups of veinlets pertaining to four stages of mineralization were recognized. Sulfur isotope studies in the Sarcheshmeh porphyry copper deposit were conducted on pyrite, chalcopyrite, molybdenite and anhydrites of four groups of veinlets. The δ34S values in the sulfides and sulfates range from -2.2 to 1.27‰ and from 10.2 to 14.5 ‰, respectively. The average δ34S value in the sulfides is 1‰ and that for the sulfates is about 13‰. Considering these results, it can be concluded that the