Preparation and properties of KCl-doped Cu2O thin film by electrodeposition

International Nuclear Information System (INIS)

Yu, Xiaojiao; Li, Xinming; Zheng, Gang; Wei, Yuchen; Zhang, Ama; Yao, Binghua

2013-01-01

With the indium tin oxide-coated glass as working electrode, cuprous oxide thin film is fabricated by means of electrodeposition. The effects of KCl doped and annealing treatment upon Cu 2 O thin film morphology, surface resistivity, open-circuit voltage, electric conduction types and visible light response are studied. The research results indicate that KCl doped has a great effect upon Cu 2 O crystal morphology, thus, making Cu 2 O thin film surface resistivity drop, and the open-circuit voltage increase and that electric conduction types are transformed from p type into n type, and the visible light (400–500 nm) absorption rate is slightly reduced. Annealing treatment can obviously decrease Cu 2 O thin film surface resistivity and improve its open-circuit voltage. When KCl concentration in electrolytic solution reaches 7 mmol/L, Cu 2 O thin film morphology can be changed from the dendritic crystal into the cubic crystal and Cu 2 O thin film surface resistivity decreases from the initial 2.5 × 10 6 Ω cm to 8.5 × 10 4 Ω cm. After annealing treatment at 320 °C for 30 min, the surface resistivity decreases to 8.5 × 10 2 Ω cm, and the open-circuit voltage increases from the initial 3.1 mV to 79.2 mV.

Characterisation of electrodeposited polycrystalline uranium dioxide thin films on nickel foil for industrial applications

International Nuclear Information System (INIS)

Adamska, A.M.; Bright, E. Lawrence; Sutcliffe, J.; Liu, W.; Payton, O.D.; Picco, L.; Scott, T.B.

2015-01-01

Polycrystalline uranium dioxide thin films were grown on nickel substrates via aqueous electrodeposition of a precursor uranyl salt. The arising semiconducting uranium dioxide thin films exhibited a tower-like morphology, which may be suitable for future application in 3D solar cell applications. The thickness of the homogenous, tower-like films reached 350 nm. Longer deposition times led to the formation of thicker (up to 1.5 μm) and highly porous films. - Highlights: • Electrodeposition of polycrystalline UO_2 thin films • Tower-like morphology for 3D solar cell applications • Novel technique for separation of heavy elements from radioactive waste streams

Electrodeposited Structurally Stable V2O5 Inverse Opal Networks as High Performance Thin Film Lithium Batteries.

Science.gov (United States)

Armstrong, Eileen; McNulty, David; Geaney, Hugh; O'Dwyer, Colm

2015-12-09

High performance thin film lithium batteries using structurally stable electrodeposited V2O5 inverse opal (IO) networks as cathodes provide high capacity and outstanding cycling capability and also were demonstrated on transparent conducting oxide current collectors. The superior electrochemical performance of the inverse opal structures was evaluated through galvanostatic and potentiodynamic cycling, and the IO thin film battery offers increased capacity retention compared to micron-scale bulk particles from improved mechanical stability and electrical contact to stainless steel or transparent conducting current collectors from bottom-up electrodeposition growth. Li(+) is inserted into planar and IO structures at different potentials, and correlated to a preferential exposure of insertion sites of the IO network to the electrolyte. Additionally, potentiodynamic testing quantified the portion of the capacity stored as surface bound capacitive charge. Raman scattering and XRD characterization showed how the IO allows swelling into the pore volume rather than away from the current collector. V2O5 IO coin cells offer high initial capacities, but capacity fading can occur with limited electrolyte. Finally, we demonstrate that a V2O5 IO thin film battery prepared on a transparent conducting current collector with excess electrolyte exhibits high capacities (∼200 mAh g(-1)) and outstanding capacity retention and rate capability.

Preparation and properties of KCl-doped Cu{sub 2}O thin film by electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Yu, Xiaojiao, E-mail: yxjw@xaut.edu.cn [Xi’an University of Technology, Xi’an 710048 (China); Li, Xinming [Xi’an University of Technology, Xi’an 710048 (China); Zheng, Gang [Xi’an University of Technology, Xi’an 710048 (China); Northwestern Polytechnical University, Xi’an 710072 (China); Wei, Yuchen [The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong (China); Zhang, Ama; Yao, Binghua [Xi’an University of Technology, Xi’an 710048 (China)

2013-04-01

With the indium tin oxide-coated glass as working electrode, cuprous oxide thin film is fabricated by means of electrodeposition. The effects of KCl doped and annealing treatment upon Cu{sub 2}O thin film morphology, surface resistivity, open-circuit voltage, electric conduction types and visible light response are studied. The research results indicate that KCl doped has a great effect upon Cu{sub 2}O crystal morphology, thus, making Cu{sub 2}O thin film surface resistivity drop, and the open-circuit voltage increase and that electric conduction types are transformed from p type into n type, and the visible light (400–500 nm) absorption rate is slightly reduced. Annealing treatment can obviously decrease Cu{sub 2}O thin film surface resistivity and improve its open-circuit voltage. When KCl concentration in electrolytic solution reaches 7 mmol/L, Cu{sub 2}O thin film morphology can be changed from the dendritic crystal into the cubic crystal and Cu{sub 2}O thin film surface resistivity decreases from the initial 2.5 × 10{sup 6} Ω cm to 8.5 × 10{sup 4} Ω cm. After annealing treatment at 320 °C for 30 min, the surface resistivity decreases to 8.5 × 10{sup 2} Ω cm, and the open-circuit voltage increases from the initial 3.1 mV to 79.2 mV.

Growth and characterisation of potentiostatically electrodeposited Cu2O and Cu thin films

International Nuclear Information System (INIS)

Wijesundera, R.P.; Hidaka, M.; Koga, K.; Sakai, M.; Siripala, W.

2006-01-01

Cuprous oxide and copper thin films were potentiostatically electrodeposited in an acetate bath. Voltammetric curves were used to investigate the growth parameters; deposition potential, pH and temperature of the bath. Deposition potential dependency on the structural, morphological, optical and electronic properties of the films were investigated by the X-ray diffraction measurements, scanning electron micrographs, absorption measurements and dark and light current-voltage characterisations. It was observed that single phase polycrystalline Cu 2 O can be deposited from 0 to - 300 mV Vs saturated calomel electrode (SCE) and co-deposition of Cu and Cu 2 O starts at - 400 mV Vs SCE. Further increase in deposition potential from - 700 mV Vs SCE produces single phase Cu thin films. Single phase polycrystalline Cu 2 O thin films with cubic grains of 1-2 μm can be possible within the very narrow potential domain around - 200 mV Vs SCE. Enhanced photoresponse in a photoelectrochemical cell is produced by the Cu 2 O thin film prepared at - 400 mV Vs SCE, where Cu is co-deposited with Cu 2 O with random distribution of Cu spheres on the Cu 2 O surface. This study reveals that a single deposition bath can be used to deposit both Cu and Cu 2 O separately and an admixture of Cu-Cu 2 O by controlling the deposition parameters

Properties of pulsed electrodeposited CdIn2S4 thin film

International Nuclear Information System (INIS)

Hankare, P.P.; Kokate, A.V.; Asabe, M.R.; Delekar, S.D.; Chougule, B.K.

2006-01-01

CdIn 2 S 4 thin films are prepared by pulsed electrodeposition technique over F:SnO 2 glass and stainless steel substrates in galvanostatic mode from an aqueous acidic bath containing CdSO 4 , InCl 3 and Na 2 S 2 O 3 . The growth kinetics of the film was studied and the deposition parameters such as electrolyte bath concentration, bath temperature, time of deposition, deposition current, and pH of the electrolyte bath are optimized. X-ray diffraction (XRD) analysis of the as deposited and annealed films showed the presence of polycrystalline nature. Energy dispersive analysis (EDAX) spectrum of the surface composition confirms the nearly stoichiometric CdIn 2 S 4 nature of the film. Surface morphology studies by scanning electron microscope (SEM) shows that, the deposited films are well adherent and grains are uniformly distributed over the surface of substrate. The optical transmission spectra show a direct band gap value of 2.16 eV

ZnTe Amorphous Semiconductor Nanowires Array Electrodeposited into Polycarbonate Membrane Thin Films

International Nuclear Information System (INIS)

Ohgai, T; Ikeda, T; Ohta, J

2013-01-01

ZnTe amorphous semiconductor nanowires array was electrodeposited into the nanochannels of ion-track etched polycarbonate membrane thin films from acidic aqueous solution at 313 K. ZnTe electrodeposits with Zn-rich composition was obtained over the wide range of cathode potential from −0.8 V to −1.1 V and the growth rate of ZnTe amorphous nanowires was around 3 nm.sec −1 at the cathode potential of −0.8 V. Cylindrical shape of the nanowires was precisely transferred from the nanochannels and the aspect ratio reached up to ca. 40. ZnTe amorphous phase electrodeposited at 313 K was crystallized by annealing at 683 K and the band gap energy of ZnTe crystalline phase reached up to ca. 2.13 eV.

Potencialidades do dióxido de chumbo eletrodepositado como sensor potenciométrico Potentialities of electrodeposited lead dioxide as a potentiometric sensor

Directory of Open Access Journals (Sweden)

Milton Duffles Capelato

1998-07-01

Full Text Available This paper proposes an experiment to be performed in both instrumental analysis and experimental physical-chemistry curricular disciplines in order to open options to develop challenging basic research activities. Thus the experimental procedures and the results obtained in the preparation of electrodeposited lead dioxide onto graphite and its evaluation as potentiometric sensor for H3O+ and Pb2+ ions, are presented. The data obtained in acid-base titrations were compared with those of the traditional combination glass electrode at the same conditions. Although a linear sub-Nernstian response to free hydrogen ions was observed for the electrodeposited PbO2 electrode, a good agreement was obtained between them. Working as lead(II sensing electrode, the PbO2 showed a linear sub-Nernstian behavior at total Pb2+ concentrations ranging from 3,5 x 10-4 to 3,0 x 10-2 mol/L in nitrate media. For the redox couple PbO2/Pb(II the operational slope converges to the theoretical one, as the acidity of the working solution increases.

Dual-bath electrodeposition of n-type Bi–Te/Bi–Se multilayer thin films

Energy Technology Data Exchange (ETDEWEB)

Matsuoka, Ken; Okuhata, Mitsuaki; Takashiri, Masayuki, E-mail: takashiri@tokai-u.jp

2015-11-15

N-type Bi–Te/Bi–Se multilayer thin films were prepared by dual-bath electrodeposition. We varied the number of layers from 2 to 10 while the total film thickness was maintained at approximately 1 μm. All the multilayer films displayed the X-ray diffraction peaks normally observed from individual Bi{sub 2}Te{sub 3} and Bi{sub 2}Se{sub 3} crystal structures, indicating that both phases coexist in the multilayer. The cross-section of the 10-layer Bi–Te/Bi–Se film was composed of stacked layers with nano-sized grains but the boundaries between the layers were not planar. The Seebeck coefficient was almost constant throughout the entire range of our experiment, but the electrical conductivity of the multilayer thin films increased significantly as the number of layers was increased. This may be because the electron mobility increases as the thickness of each layer is decreased. As a result of the increased electrical conductivity, the power factor also increased with the number of layers. The maximum power factor was 1.44 μW/(cm K{sup 2}) for the 10-layer Bi–Te/Bi–Se film, this was approximately 3 times higher than that of the 2-layer sample. - Highlights: • N-type Bi–Te/Bi–Se multilayer thin films were deposited by electrodeposition. • We employed a dual-bath electrodeposition process for preparing the multilayers. • The Bi–Te/Bi–Se film was composed of stacked layers with nano-sized grains. • The electrical conductivity increased as the number of layers was increased. • The power factor improved by 3 times as the number of layers was increased.

Preparation of cuxinygazsen (X=0-2, Y=0-2, Z=0-2, N=0-3) precursor films by electrodeposition for fabricating high efficiency solar cells

Science.gov (United States)

Bhattacharya, Raghu N.; Contreras, Miguel A.; Keane, James; Tennant, Andrew L.; Tuttle, John R.; Ramanathan, Kannan; Noufi, Rommel

1998-03-24

High quality thin films of copper-indium-gallium-diselenide useful in the production of solar cells are prepared by electrodepositing at least one of the constituent metals onto a glass/Mo substrate, followed by physical vapor deposition of copper and selenium or indium and selenium to adjust the final stoichiometry of the thin film to approximately Cu(In,Ga)Se.sub.2. Using an AC voltage of 1-100 KHz in combination with a DC voltage for electrodeposition improves the morphology and growth rate of the deposited thin film. An electrodeposition solution comprising at least in part an organic solvent may be used in conjunction with an increased cathodic potential to increase the gallium content of the electrodeposited thin film.

Molecular beam epitaxy of three-dimensional Dirac material Sr3PbO

Science.gov (United States)

Samal, D.; Nakamura, H.; Takagi, H.

2016-07-01

A series of anti-perovskites including Sr3PbO are recently predicted to be a three-dimensional Dirac material with a small mass gap, which may be a topological crystalline insulator. Here, we report the epitaxial growth of Sr3PbO thin films on LaAlO3 using molecular beam epitaxy. X-ray diffraction indicates (001) growth of Sr3PbO, where [110] of Sr3PbO matches [100] of LaAlO3. Measurements of the Sr3PbO films with parylene/Al capping layers reveal a metallic conduction with p-type carrier density of ˜1020 cm-3. The successful growth of high quality Sr3PbO film is an important step for the exploration of its unique topological properties.

One-step electrodeposition process of CuInSe2: Deposition time effect

Indian Academy of Sciences (India)

Administrator

CuInSe2 thin films were prepared by one-step electrodeposition process using a simplified two- electrodes system. ... homojunctions or heterojunctions (Rincon et al 1983). Efficiency of ... deposition times onto indium thin oxide (ITO)-covered.

Investigation of the magnetic properties of electrodeposited NiFe thin films

International Nuclear Information System (INIS)

Bakkaloglu, O. F.; Bedir, M.; Oeztas, M.; Karahan, I. H.

2002-01-01

Most magnetic devices used today are based on the magnetic thin film. Rapid and extensive developments in magnetic sensor / actuator and magnetic recording technology place a growing demand on the use of different thin film fabrication techniques for magnetic materials. The electroplating technique is especially interesting due to its low cost, high throughput and high quality of the deposits which are extensively used in the magnetic recording industry to deposit relatively thick permalloy layers. Much recent attention has focused on the electrodeposited NiFe thin films, which exhibit giant magneto resistive behaviour as well as anisotropic magnetoresistance properties. n this study, NiFe thin films were developed by using electrodeposition technique and their crystallinity structures were investigated by using x-ray diffractometer measurements. The magneto resistive properties of the samples were investigated by Wan der Pauw method with a home made electromagnet under the different magnetic fields. The magnetoresistance measurements of the samples were carried out in two configurations; current parallel ( longitudinal ) and perpendicular ( transverse ) to the magnetic field. In the longitudinal configuration giant magnetoresistance was observed while anisotropic magnetoresistance was detected in the other configuration

Studies on electrodeposited Cd1-xFe xS thin films

International Nuclear Information System (INIS)

Deshmukh, S.K.; Kokate, A.V.; Sathe, D.J.

2005-01-01

Thin films of Cd 1-x Fe x S have been prepared on stainless steel and fluorine doped tin oxide (FTO) coated glass substrates using electrodeposition technique. Double distilled water containing precursors of Cd, Fe and S are used with ethylene diamine tetra-acetic acid (EDTA) disodium salt as a complexing agent to obtain good quality deposits by controlling the rate of reactions. The different preparative parameters like concentration of bath, deposition time, pH of the bath and Fe content in the bath have been optimized by photoelectrochemical (PEC) technique in order to get good quality thin films. Different techniques have been used to characterize electrodeposited Cd 1-x Fe x S thin films. The X-ray diffraction (XRD) analysis reveals that the films Cd 1-x Fe x S are polycrystalline in nature with crystallite size 282 A for the films deposited with optimized preparative parameters. Scanning electron microscopy (SEM) study for the sample deposited at optimized preparative parameters reveals that all grains uniformly distributed over the surface of stainless steel substrate indicates well defined growth of polycrystalline Cd-Fe-S material. Optical absorption shows the presence of direct transition and band gap energy decreases from 2.43 to 0.81 eV with the increase of Fe content from 0 to 1. PEC study shows the films of Cd 1-x Fe x S with x = 0.2 are more photosensitive than other compositions

One, step electrodeposition of Cu(Ga,In)Se2 thin films from aqueous solution

Science.gov (United States)

Fahoume, M.; Boudraine, H.; Aggour, M.; Chraïbi, F.; Ennaoui, A.; Delplancke, J. L.

2005-03-01

Cu(In,Ga)Se{2} (CIGS) semiconducting thin films films were prepared by electrodeposition from aqueous solution containing CuCl{2}, InCl{3}, GaCl{3} and H{2}SeO{3}. The deposited material was characterized by cyclic voltammetry. The compositional, structural studies were carried out using scanning electron microscopy (SEM), energy dispersive X-ray microanalysis (EDX), X-ray diffraction (XRD) and transmission electron microscopy (TEM). X-ray analysis showed the formation of CuIn{1-x}GaxSe{2} films, in the optimum conditions, with preferred orientation in the (112) direction. We observed a shift of the peaks to higher angles with increasing x, accounting for a decrease of the lattice constants when In atoms are substituted by Ga atoms. Element mapping and scanline (EDX) indicate that the Cu, In, Ga, and Se elements are homogeneously distributed.

Electrodeposition of CdTe thin film from acetate-based ionic liquid bath

Science.gov (United States)

Waldiya, Manmohansingh; Bhagat, Dharini; Mukhopadhyay, Indrajit

2018-05-01

CdTe being a direct band gap semiconductor, is mostly used in photovoltaics. Here we present, the synthesis of CdTe thin film on fluorine doped tin oxide (FTO) substrate potentiostatically using 1-butyl-3-methylimidazolium acetate ([Bmim][Ac]) ionic liquid (IL) bath at 90 °C. Major advantages of using electrodeposition involves process simplicity, large scalability & economic viability. Some of the benefits offered by IL electrolytic bath are low vapour pressure, wide electrochemical window, and good ionic mobility. Cd(CH3COO)2 (anhydrous) and TeO2 were used as the source precursors. The IL electrolytic bath temperature was kept at 90 °C for deposition, owing to the limited solubility of TeO2 in [Bmim][Ac] IL at room temperature. Cathodic electrodeposition was carried out using a three electrode cell setup at a constant potential of -1.20 V vs. platinum (Pt) wire. The CdTe/FTO thin film were annealed in argon (Ar) atmosphere. Optical study of nanostructured CdTe film were done using UV-Vis-IR and Raman spectroscopy. Raman analysis confirms the formation of CdTe having surface optics (SO) mode at 160.6 cm-1 and transverse optics (TO) mode at 140.5 cm-1. Elemental Te peaks at 123, 140.5 and 268 cm-1 were also observed. The optical band gap of Ar annealed CdTe thin film were found to be 1.47 eV (absorbance band edge ˜ 846 nm). The optimization of deposition parameters using acetate-based IL electrolytic bath to get nearly stoichiometric CdTe thin film is currently being explored.

Composition and performance of thin film CdSe electrodeposited from selenosulfite solution

International Nuclear Information System (INIS)

Szabo, J.P.; Simms, D.; Cocivera, M.

1985-01-01

Cathodic electrodeposition of thin film CdSe from aqueous selenosulfite solution has been studied as function of solution composition and electrode potential. The Cd/Se ratio has been analyzed using polarography and Rutherford backscattering spectroscopy. Polarography gives a compostion averaged over the whole film (2cm 2 ) while RBS gives local surface composition (1 mm 2 ). The average Cd/Se ratio is 1.1, but some variation was found to occur across the surface of film (0.82 to 1.2)

Crystallization of Electrodeposited Germanium Thin Film on Silicon (100

Directory of Open Access Journals (Sweden)

Abdul Manaf Hashim

2013-11-01

Full Text Available We report the crystallization of electrodeposited germanium (Ge thin films on n-silicon (Si (100 by rapid melting process. The electrodeposition was carried out in germanium (IV chloride: propylene glycol (GeCl4:C3H8O2 electrolyte with constant current of 50 mA for 30 min. The measured Raman spectra and electron backscattering diffraction (EBSD images show that the as-deposited Ge thin film was amorphous. The crystallization of deposited Ge was achieved by rapid thermal annealing (RTA at 980 °C for 1 s. The EBSD images confirm that the orientations of the annealed Ge are similar to that of the Si substrate. The highly intense peak of Raman spectra at 300 cm−1 corresponding to Ge-Ge vibration mode was observed, indicating good crystal quality of Ge. An additional sub peak near to 390 cm−1 corresponding to the Si-Ge vibration mode was also observed, indicating the Ge-Si mixing at Ge/Si interface. Auger electron spectroscopy (AES reveals that the intermixing depth was around 60 nm. The calculated Si fraction from Raman spectra was found to be in good agreement with the value estimated from Ge-Si equilibrium phase diagram. The proposed technique is expected to be an effective way to crystallize Ge films for various device applications as well as to create strain at the Ge-Si interface for enhancement of mobility.

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.

Electrodeposited ZnIn{sub 2}S{sub 4} onto TiO{sub 2} thin films for semiconductor-sensitized photocatalytic and photoelectrochemical applications

Energy Technology Data Exchange (ETDEWEB)

Assaker, Ibtissem Ben, E-mail: ibtissem.ben-assaker@laposte.net [Laboratoire Photovoltaïque, Centre de Recherches et des Technologies de l’Energie Technopole borj cedria, Bp 95, Hammamm lif 2050 (Tunisia); Gannouni, Mounir; Naceur, Jamila Ben [Laboratoire Photovoltaïque, Centre de Recherches et des Technologies de l’Energie Technopole borj cedria, Bp 95, Hammamm lif 2050 (Tunisia); Almessiere, Munirah Abdullah; Al-Otaibi, Amal Lafy; Ghrib, Taher [Laboratory of Physical Alloys (LPA), College of Science, University of Dammam (Saudi Arabia); Shen, Shouwen [Advanced Analysis Unit, Technical Service Division Research & Development Center Saudi Aramco, Dhahran (Saudi Arabia); Chtourou, Radhouane [Laboratoire Photovoltaïque, Centre de Recherches et des Technologies de l’Energie Technopole borj cedria, Bp 95, Hammamm lif 2050 (Tunisia)

2015-10-01

Graphical abstract: - Highlights: • ZnIn{sub 2}S{sub 4} thin films was grown using electrodeposition route onto TiO{sub 2}/ITO coated glass substrate. • Study of the heterostructure ZnIn{sub 2}S{sub 4}/TiO{sub 2} thin films. • Photocatalytic activity of ZnIn{sub 2}S{sub 4}/TiO{sub 2} heterostructure under visible light irradiation. • High performance of Photoelectrochemical properties in the presence of the junction ZnIn{sub 2}S{sub 4}/TiO{sub 2}. - Abstract: In this study, ZnIn{sub 2}S{sub 4}/TiO{sub 2} heterostructure was successfully synthesized on ITO-coated glass substrates via a facile two-step process from aqueous solution. First, TiO{sub 2} thin film was prepared by sol–gel and deposited onto ITO coated glass substrate by spin-coating method. Then the zinc indium sulfide semiconductor was fabricated via electrodeposition technique onto TiO{sub 2}/ITO coated glass electrode. The X-ray diffraction patterns confirm that the heterostructure is mixed of both Anatase TiO{sub 2} and Rhombohedric ZnIn{sub 2}S{sub 4}. The scanning electron microscopy (SEM) images show that the morphology change with the deposition of ZnIn{sub 2}S{sub 4} over TiO{sub 2} thin film and a total coverage of the electrode surface was obtained. Optical absorption spectroscopy study of ZnIn{sub 2}S{sub 4}/TiO{sub 2} heterostructure exhibits a remarkable red-shift compared to the TiO{sub 2} and ZnIn{sub 2}S{sub 4} achieve the best efficiency of visible light absorption. Therefore, it is expected to apply to visible-light photocatalysis and solar cells. To investigate the effect of the heterojunction on the photocatalytic activity of ZnIn{sub 2}S{sub 4}/TiO{sub 2} thin films, photodegradation of methylene blue in the presence of ZnIn{sub 2}S{sub 4} was performed. ZnIn{sub 2}S{sub 4}/TiO{sub 2} heterostructure exhibited strong photocatalytic activity, and the degradation of methylene blue eached 91% after irradiation only for 4 h. Also, the study of the photocurrent density produced

Characterization of thin Zn-Ni alloy coatings electrodeposited on low carbon steel

International Nuclear Information System (INIS)

El Hajjami, A.; Gigandet, M.P.; De Petris-Wery, M.; Catonne, J.C.; Duprat, J.J.; Thiery, L.; Raulin, F.; Pommier, N.; Starck, B.; Remy, P.

2007-01-01

The characteristics of initial layer formation in alkaline bath for Zn-Ni (12-15%) alloy electrodeposition on low carbon steel plates are detected in a nanometric thickness range by electron probe microanalysis (EPMA), with both bulk sample and thin film on substrate correction procedure, glow discharge optical emission spectroscopy (GDOES) and gracing incidence X-ray diffraction (GIXRD). The Zn-Ni coatings were elaborated using either intensiostatic or potentiostatic mode. A preferential deposition of Ni, in the initial thin layer, is detected by these analyses; according to EPMA and GDOES measurements, a layer rich in nickel at the interface substrate/deposit is observed (90 wt.% Ni) and approved by GIXRD; the thin layer of Ni formed in the first moments of electrolysis greatly inhibits the Zn deposition. The initial layer depends upon the relative ease of hydrogen and metal discharge and on the different substrate surfaces involved. The electrodeposition of zinc-nickel alloys in the first stage is a normal phenomenon of codeposition, whereby nickel - the more noble metal - is deposited preferentially

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.

Structural and electrical properties of CZTS thin films by electrodeposition

Science.gov (United States)

Rao, M. C.; Basha, Sk. Shahenoor

2018-06-01

CZTS (Cu2ZnSnS4) thin films were coated on ITO glass substrates by single bath electrodeposition technique. The prepared films were subsequently characterized by XRD, SEM, FTIR, UV-visible spectroscopy and Raman studies. The thickness of the thin films was measured by wedge method. X-ray diffraction studies revealed the formation of polycrystalline phase. The morphological surface of the prepared thin films was examined by SEM and AFM and showed the presence of microcrystals on the surface of the samples. The elemental analysis and their compositional ratios present in the samples were confirmed by the energy dispersive X-ray analysis. Functional groups and the position of band structure involved in the materials were confirmed by FTIR. Optical absorption studies were performed on the prepared thin films in the wavelength ranging from 300 to 1000 nm and the energy bandgap values were found to be in the range from 1.39 to 1.60 eV. Raman spectral peak which was observed at 360 cm-1 correspond to kesterite phase, was formed due to the vibration of the molecules. Electrical measurements confirmed the nature of the thin film depending on the charge concentration present in the samples.

Effect of Electrodeposition Potential on Composition of CuIn1−xGaxSe2 Absorber Layer for Solar Cell by One-Step Electrodeposition

Directory of Open Access Journals (Sweden)

Rui-Wei You

2014-01-01

Full Text Available CIGS polycrystalline thin films were successfully fabricated by one-step cathodic electrodeposition on Mo-coated glass. In this study, we applied a galvanometry mode with three-electrode potentiostatic systems to produce a constant concentration electroplating solution, which were composed of CuCl2, InCl3, GaCl3, and SeO2. Then these as-electrodeposited films were annealed in argon atmosphere and characterized by X-ray diffraction. The results revealed that annealing treatment significantly improved the crystallinity of electrodeposited films and formed CIGS chalcopyrite structure, but at low applied deposition voltage (−950 mV versus SCE there appeared second phase. The cross-section morphology revealed that applied voltage at −1350 mV versus SCE has uniform deposition, and higher applied voltage made grain more unobvious. The deposition rate and current density are proportional to deposition potential, and hydrogen was generated apparently when applying potential beyond −1750 mV versus SCE. It was found that the CIGS compound did not match exact stoichiometry of Cu : In : Ga : Se =1 : x : 1-x : 2. This result suggests the possibility of controlling the property of thin films by varying the applied potential during electrodeposition.

Effect of Electrodeposition Potential on Composition of CuIn1−xGaxSe2 Absorber Layer for Solar Cell by One-Step Electrodeposition

OpenAIRE

You, Rui-Wei; Lew, Kar-Kit; Fu, Yen-Pei

2014-01-01

CIGS polycrystalline thin films were successfully fabricated by one-step cathodic electrodeposition on Mo-coated glass. In this study, we applied a galvanometry mode with three-electrode potentiostatic systems to produce a constant concentration electroplating solution, which were composed of CuCl2, InCl3, GaCl3, and SeO2. Then these as-electrodeposited films were annealed in argon atmosphere and characterized by X-ray diffraction. The results revealed that annealing treatment significantly i...

Electrodeposition of nanocrystalline CdSe thin films from dimethyl sulfoxide solution: Nucleation and growth mechanism, structural and optical studies

International Nuclear Information System (INIS)

Henriquez, R.; Badan, A.; Grez, P.; Munoz, E.; Vera, J.; Dalchiele, E.A.; Marotti, R.E.; Gomez, H.

2011-01-01

Highlights: → Electrodeposition of CdSe nanocrystalline semiconductor thin films. → Polycrystalline wurtzite structure with a slight (1010) preferred orientation. → Absorption edge shifts in the optical properties due to quantum confinement effects. - Abstract: Cadmium selenide (CdSe) nanocrystalline semiconductor thin films have been synthesized by electrodeposition at controlled potential based in the electrochemical reduction process of molecular selenium in dimethyl sulfoxide (DMSO) solution. The nucleation and growth mechanism of this process has been studied. The XRD pattern shows a characteristic polycrystalline hexagonal wurtzite structure with a slight (1 0 1 0) crystallographic preferred orientation. The crystallite size of nanocrystalline CdSe thin films can be simply controlled by the electrodeposition potential. A quantum size effect is deduced from the correlation between the band gap energy and the crystallite size.

Electrodeposition of Metal Matrix Composites and Materials Characterization for Thin-Film Solar Cells

Science.gov (United States)

2017-12-04

Air Mass CNT Carbon Nanotubes DIV Dark Current -Voltage DMA Dynamic Mechanical Analysis EL Electroluminescence FEM Finite Element Method IMM...AFRL-RV-PS- AFRL-RV-PS- TR-2017-0174 TR-2017-0174 ELECTRODEPOSITION OF METAL MATRIX COMPOSITES AND MATERIALS CHARACTERIZATION FOR THIN-FILM SOLAR...research which is exempt from public affairs security and policy review in accordance with AFI 61-201, paragraph 2.3.5.1. This report is available to

Microstructure and optical properties of nanocrystalline Cu2O thin films prepared by electrodeposition.

Science.gov (United States)

Jiang, Xishun; Zhang, Miao; Shi, Shiwei; He, Gang; Song, Xueping; Sun, Zhaoqi

2014-01-01

Cuprous oxide (Cu2O) thin films were prepared by using electrodeposition technique at different applied potentials (-0.1, -0.3, -0.5, -0.7, and -0.9 V) and were annealed in vacuum at a temperature of 100°C for 1 h. Microstructure and optical properties of these films have been investigated by X-ray diffractometer (XRD), field-emission scanning electron microscope (SEM), UV-visible (vis) spectrophotometer, and fluorescence spectrophotometer. The morphology of these films varies obviously at different applied potentials. Analyses from these characterizations have confirmed that these films are composed of regular, well-faceted, polyhedral crystallites. UV-vis absorption spectra measurements have shown apparent shift in optical band gap from 1.69 to 2.03 eV as the applied potential becomes more cathodic. The emission of FL spectra at 603 nm may be assigned as the near band-edge emission.

Effect of bath temperature on the properties of CuIn{sub x}Ga{sub 1-x} Se{sub 2} thin films grown by the electrodeposition technique

Energy Technology Data Exchange (ETDEWEB)

Cao Jie; Qu Shengchun; Liu Kong; Wang Zhanguo, E-mail: qsc@semi.ac.c [Key Laboratory of Semiconductor Materials Science, Institute of Semiconductors, Chinese Academy of Sciences, Beijing 100083 (China)

2010-08-15

Electrodeposition is a promising and low cost method to synthesize CuIn{sub x} Ga{sub 1-x} Se{sub 2} (CIGS)thin films as an absorber layer for solar cells. The effect of bath temperature on the properties of CIGS thin films was investigated in this paper. CIGS films of 1 {mu}m thickness were electrodeposited potentiostatically from aqueous solution, containing trisodium citrate as a complexing agent, on Mo/glass substrate under a voltage of -0.75 V, and bath temperatures were varied from 20 to 60{sup 0}C. The effects of bath temperature on the properties of CIGS thin films were characterized by X-ray diffraction (XRD) and scanning electron microscopy. XRD revealed the presence of the CuIni{sub 0.7}Ga{sub 0.3} Se{sub 2} phase, the optimal phase for application in solar cells. The grain dimensions and crystallizability increase along with the increase of the bath temperature, and the films become stacked and homogeneous. There were few changes in surface morphology and the composition of the films. (semiconductor materials)

Phase equilibria and interaction between the CsCl-PbCl{sub 2}-PbO system components

Energy Technology Data Exchange (ETDEWEB)

Arkhipov, Pavel A.; Zakiryanova, Irina D. [Russian Academy of Sciences, Ekatherinburg (Russian Federation). Inst. of High Temperature Electrochemistry; Kholkina, Anna S.; Bausheva, Alexandra V.; Khudorozhkova, Anastasia O. [Russian Academy of Sciences, Ekatherinburg (Russian Federation). Inst. of High Temperature Electrochemistry; Ural Federal Univ., Ekatherinburg (Russian Federation)

2015-07-01

Thermal analysis was applied to determine liquidus temperatures in the CsCl-PbCl{sub 2}-PbO system, with the PbO concentration ranging from 0 to 20 mol%. The temperature dependence of the PbO solubility in the CsCl-PbCl{sub 2} eutectic melt was studied, and the thermodynamic parameters of the PbO dissolution were calculated. The type, morphology, and composition of oxychloride ionic groupings in the melt were determined in situ using Raman spectroscopy.

Crystallization of Electrodeposited Germanium Thin Film on Silicon (100).

Science.gov (United States)

Abidin, Mastura Shafinaz Zainal; Matsumura, Ryo; Anisuzzaman, Mohammad; Park, Jong-Hyeok; Muta, Shunpei; Mahmood, Mohamad Rusop; Sadoh, Taizoh; Hashim, Abdul Manaf

2013-11-06

We report the crystallization of electrodeposited germanium (Ge) thin films on n-silicon (Si) (100) by rapid melting process. The electrodeposition was carried out in germanium (IV) chloride: propylene glycol (GeCl₄:C₃H₈O₂) electrolyte with constant current of 50 mA for 30 min. The measured Raman spectra and electron backscattering diffraction (EBSD) images show that the as-deposited Ge thin film was amorphous. The crystallization of deposited Ge was achieved by rapid thermal annealing (RTA) at 980 °C for 1 s. The EBSD images confirm that the orientations of the annealed Ge are similar to that of the Si substrate. The highly intense peak of Raman spectra at 300 cm -1 corresponding to Ge-Ge vibration mode was observed, indicating good crystal quality of Ge. An additional sub peak near to 390 cm -1 corresponding to the Si-Ge vibration mode was also observed, indicating the Ge-Si mixing at Ge/Si interface. Auger electron spectroscopy (AES) reveals that the intermixing depth was around 60 nm. The calculated Si fraction from Raman spectra was found to be in good agreement with the value estimated from Ge-Si equilibrium phase diagram. The proposed technique is expected to be an effective way to crystallize Ge films for various device applications as well as to create strain at the Ge-Si interface for enhancement of mobility.

Dielectric properties investigation of Cu2O/ZnO heterojunction thin films by electrodeposition

International Nuclear Information System (INIS)

Li, Qiang; Xu, Mengmeng; Fan, Huiqing; Wang, Hairong; Peng, Biaolin; Long, Changbai; Zhai, Yuchun

2013-01-01

Highlights: ► Bottom-up self-assembly Cu 2 O/ZnO heterojunction was fabricated by electrochemical deposition on indium tin oxide (ITO) flexible substrate (polyethylene terephthalate-PET). ► The dielectric response of Cu 2 O/ZnO heterojunction thin films had been investigated. ► The universal dielectric response was used to investigate the hopping behavior in Cu 2 O/ZnO heterojunction. -- Abstract: Structures and morphologies of the Cu 2 O/ZnO heterojunction electrodeposited on indium tin oxide (ITO) flexible substrate (polyethylene terephthalate-PET) were investigated by X-ray diffraction (XRD), scanning electronic microscopy (SEM), high resolution transmission electron microscopy (HRTEM), respectively. The dielectric response of bottom-up self-assembly Cu 2 O/ZnO heterojunction was investigated. The low frequency dielectric dispersion (LFDD) was observed. The universal dielectric response (UDR) was used to investigate the frequency dependence of dielectric response for Cu 2 O/ZnO heterojunction, which was attributed to the long range and the short range hopping charge carriers at the low frequency and the high frequency region, respectively

Production of CdTe Semiconductor Thin Films by Electrodeposition Technique for Solar Cell Applications

Directory of Open Access Journals (Sweden)

Ahmet PEKSÖZ

2016-08-01

Full Text Available Electro-deposited cadmium tellurite (CuTe thin film was grown onto ITO-coated glass substrate for 120 seconds at the room temperature and a constant cathodic potential of -0.85 V. Deposition solution was prepared from cadmium chloride (CdCl2, sodium tellurite (Na2TeO3 and pure water. The pH value of the deposition solution was adjusted to 2.0 by adding HCl. The EDX analysis shows that the film has 52% Cd and 48% Te elemental compositions. Film thickness was found to be 140 nm. The CdTe thin film exhibits p-type semiconductor character, and has an energy bandgap of 1.47 eV. 

Electrodeposition of thin Pd-Ag films

International Nuclear Information System (INIS)

Hasler, P.; Allmendinger, T.

1993-01-01

Thin Pd-Ag layers were electroplated preferably on brass and on nickel substrates using a two-compartment cell separated by an anion exchange membrane. The weakly alkaline electrolyte contained glycine-glycinate as the major complexing agents. The plating experiments were usually carried out without stirring, at different potentials and temperatures and in the absence or in the presence of sodium benzaldehyde-2,4-disulphonate (BDS). The samples were characterized by scanning electron microscopy and light microscopy. Their compositions were determined analytically by the inductively coupled plasma technique. In addition, the film porosity was tested. Electrodeposition in almost limiting current conditions for both components and without simultaneous hydrogen evolution led to deposits with compositions being in good agreement with the molar metal ratio in the electrolyte (77:23). The best results were achieved between 0 and -50 mV with respect to a reversible hydrogen electrode at 0 C in the presence of BDS. These deposits were bright, had good adherence and exhibited no pores at a film thickness of 1.2 μm. At too negative potentials, the deposits became black and powdery. (orig.)

Indium doped zinc oxide thin films obtained by electrodeposition

International Nuclear Information System (INIS)

Machado, G.; Guerra, D.N.; Leinen, D.; Ramos-Barrado, J.R.; Marotti, R.E.; Dalchiele, E.A.

2005-01-01

Indium doped ZnO thin films were obtained by co-electrodeposition (precursor and dopant) from aqueous solution. XRD analysis showed typical patterns of the hexagonal ZnO structure for both doped and undoped films. No diffraction peaks of any other structure such as In 2 O 3 or In(OH) 3 were found. The incorporation of In into the ZnO film was verified by both EDS and XPS measurements. The bandgap energy of the films varied from 3.27 eV to 3.42 eV, increasing with the In concentration in the solution. This dependence was stronger for the less cathodic potentials. The incorporation of In into the film occurs as both, an In donor state in the ZnO grains and as an amorphous In 2 O 3 at the grain boundaries

Electrode processes during the electrorefiniment of lead in the KCl-PbCl2-PbO melt

Directory of Open Access Journals (Sweden)

P. S. Pershin

2015-03-01

Full Text Available The influence of PbO addition on current efficiency during the electrorefinement of lead in the KCl-PbCl2-PbO melt was investigated. It was shown that with PbO concentration in the KCl-PbCl2 eqiumolar mixture increasing, the current efficiency of lead decreases. Electrode processes mechanism is proposed.

Electrochemical degradation of waters containing O-Toluidine on PbO2 and BDD anodes

International Nuclear Information System (INIS)

Hmani, Emna; Chaabane Elaoud, Sourour; Samet, Youssef; Abdelhedi, Ridha

2009-01-01

Electrochemical oxidation of O-Toluidine (OT) was studied by galvanostatic electrolysis using lead dioxide (PbO 2 ) and boron-doped diamond (BDD) as anodes. The influence of operating parameters, such as current density, initial concentration of OT and temperature was investigated. Measurements of chemical oxygen demand were used to follow the oxidation. The experimental data indicated that on PbO 2 and BDD anodes, OT oxidation takes place by reaction with electrogenerated hydroxyl radicals and is favoured by low current density and high temperature. Furthermore, BDD anodes offer significant advantages over PbO 2 in terms of current efficiency and oxidation rate.

Studies on electrodeposited silver sulphide thin films by double exposure holographic interferometry

International Nuclear Information System (INIS)

Prabhune, V.B.; Shinde, N.S.; Fulari, V.J.

2008-01-01

Silver sulphide (Ag 2 S) thin films have been deposited on to stainless steel and fluorine doped tin oxide (FTO) glass substrates by the electrodeposition process, in potentiostatic mode using silver nitrate (AgNO 3 ), sodium thiosulphate (Na 2 S 2 O 3 ) as a precursor sources and Ethylene Diamine Tetra Acetic Acid (EDTA) was used as a complexing agent. The deposition potential of the compound was investigated by cyclic voltammetry. The structural and optical properties of the deposited films have been studied using X-ray diffraction (XRD) and optical absorption techniques, respectively. XRD studies reveal that the films are polycrystalline with monoclinic crystal structure. Optical absorption study shows the presence of direct transition with bandgap energy 1.1 eV. The determination of thickness and stress of the Ag 2 S thin films was carried out by Double Exposure Holographic Interferometry (DEHI) technique.

Study of the electrodeposition of rhenium thin films by electrochemical quartz microbalance and X-ray photoelectron spectroscopy

International Nuclear Information System (INIS)

Schrebler, R.; Cury, P.; Suarez, C.; Munoz, E.; Vera, F.; Cordova, R.; Gomez, H.; Ramos-Barrado, J.R.; Leinen, D.; Dalchiele, E.A.

2005-01-01

Rhenium thin films were prepared by electrodeposition from an aqueous solution containing 0.1 M Na 2 SO 4 +H 2 SO 4 , pH 2 in presence of y mM HReO 4 . As substrates polycrystalline gold (y=0.75 mM HReO 4 ) and monocrystalline n-Si(100) (y=40 mM HReO 4 ) were used. The electrochemical growth of rhenium was studied by cyclic voltammetry and electrochemical quartz microbalance on gold electrodes. The results found in the potential region before the hydrogen evolution reaction (her) showed that ReO 3 , ReO 2 and Re 2 O 3 with different hydration grades can be formed. In the potential region where the her is occurring, either on gold or n-Si(100) the electrodeposition of metallic rhenium takes place. On both substrates, rhenium films were formed by electrolysis at constant potential and X-ray photoelectron spectroscopy technique was used to characterise these deposits. It was concluded that the electrodeposited films were of metallic rhenium and only the uppermost atomic layer contained rhenium oxide species

Electrodeposition of CdSe coatings on ZnO nanowire arrays for extremely thin absorber solar cells

Energy Technology Data Exchange (ETDEWEB)

Majidi, Hasti [Department of Chemical and Biological Engineering, Drexel University, 3141 Chestnut St, Philadelphia, PA 19104 (United States); Baxter, Jason B., E-mail: jbaxter@drexel.ed [Department of Chemical and Biological Engineering, Drexel University, 3141 Chestnut St, Philadelphia, PA 19104 (United States)

2011-02-15

We report on electrodeposition of CdSe coatings onto ZnO nanowire arrays and determine the effect of processing conditions on material properties such as morphology and microstructure. CdSe-coated ZnO nanowire arrays have potential use in extremely thin absorber (ETA) solar cells, where CdSe absorbs visible light and injects photoexcited electrons into the ZnO nanowires. We show that room-temperature electrodeposition enables growth of CdSe coatings that are highly crystalline, uniform, and conformal with precise control over thickness and microstructure. X-ray diffraction and transmission electron microscopy show nanocrystalline CdSe in both hexagonal and cubic phases with grain size {approx}5 nm. Coating morphology depends on electrodeposition current density. Uniform and conformal coatings were achieved using moderate current densities of {approx}2 mA cm{sup -2} for nanowires with roughness factor of {approx}10, while lower current densities resulted in sparse nucleation and growth of larger, isolated islands. Electrodeposition charge density controls the thickness of the CdSe coating, which was exploited to investigate the evolution of the morphology at early stages of nucleation and growth. UV-vis transmission spectroscopy and photoelectrochemical solar cell measurements demonstrate that CdSe effectively sensitizes ZnO nanowires to visible light.

Electrodeposition of CdSe coatings on ZnO nanowire arrays for extremely thin absorber solar cells

International Nuclear Information System (INIS)

Majidi, Hasti; Baxter, Jason B.

2011-01-01

We report on electrodeposition of CdSe coatings onto ZnO nanowire arrays and determine the effect of processing conditions on material properties such as morphology and microstructure. CdSe-coated ZnO nanowire arrays have potential use in extremely thin absorber (ETA) solar cells, where CdSe absorbs visible light and injects photoexcited electrons into the ZnO nanowires. We show that room-temperature electrodeposition enables growth of CdSe coatings that are highly crystalline, uniform, and conformal with precise control over thickness and microstructure. X-ray diffraction and transmission electron microscopy show nanocrystalline CdSe in both hexagonal and cubic phases with grain size ∼5 nm. Coating morphology depends on electrodeposition current density. Uniform and conformal coatings were achieved using moderate current densities of ∼2 mA cm -2 for nanowires with roughness factor of ∼10, while lower current densities resulted in sparse nucleation and growth of larger, isolated islands. Electrodeposition charge density controls the thickness of the CdSe coating, which was exploited to investigate the evolution of the morphology at early stages of nucleation and growth. UV-vis transmission spectroscopy and photoelectrochemical solar cell measurements demonstrate that CdSe effectively sensitizes ZnO nanowires to visible light.

A green preparation method of battery grade α-PbO based on Pb-O2 fuel cell

Science.gov (United States)

Wang, Pingyuan; Pan, Junqing; Gong, Shumin; Sun, Yanzhi

2017-08-01

In order to solve the problem of high pollution and high energy consumption of the current lead oxide (PbO) preparation processes, a new clean and energy saving preparation method for high purity α-PbO via discharge of a Pb-O2 fuel cell is reported. The fuel cell with metallic lead anode, oxygen cathode, and 30% NaOH electrolyte can provide a discharge voltage of 0.66-0.38 V corresponding to discharge current range of 5-50 mA cm-2. PbO is precipitated from the NaHPbO2-containing electrolyte through a cooling crystallization process after discharge process, and the XRD patterns indicate the structure is pure α-PbO. The mother liquid after crystallization can be recycled for the next batch. The obtained PbO mixed with 60% Shimadzu PbO is superior to the pure Shimadzu PbO in discharge capacity and cycle ability.

Structural, optical and electrical studies on pulse electrodeposited CdIn2S4 thin films

International Nuclear Information System (INIS)

Kokate, A.V.; Asabe, M.R.; Shelake, S.B.; Hankare, P.P.; Chougule, B.K.

2007-01-01

CdIn 2 S 4 thin films were prepared by pulse electrodeposition technique over F:SnO 2 glass and stainless steel substrates in galvanostatic mode from an aqueous acidic bath containing CdSO 4 , InCl 3 and Na 2 S 2 O 3 . The growth kinetics of the film has been studied and the deposition parameters such as electrolyte bath concentration, bath temperature, time of deposition, deposition current and pH of the bath are optimized. X-ray diffraction (XRD) analysis of the as deposited and annealed films shows polycrystalline nature. Energy dispersive analysis by X-ray (EDAX) confirms nearly stoichiometric CdIn 2 S 4 nature of the film. Scanning electron microscope (SEM) studies show that, the deposited films are well adherent and grains are uniformly distributed over the surface of the substrate. The optical transmission spectra show a direct band gap of 2.16 eV. Conductivity measurements have been carried out at different temperatures and electrical parameters such as activation energy, trapped energy state and barrier heights etc. have been determined

Electrodeposition of In{sub 2}O{sub 3} thin films from a dimethylsulfoxide based electrolytic solution

Energy Technology Data Exchange (ETDEWEB)

Henriquez, R.; Munoz, E.; Gomez, H. [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Curauma Valparaiso (Chile); Dalchiele, E.A.; Marotti, R.E. [Instituto de Fisica and CINQUIFIMA, Facultad de Ingenieria, Montevideo (Uruguay); Martin, F.; Leinen, D.; Ramos-Barrado, J.R. [Laboratorio de Materiales y Superficie, Departamento de Fisica Aplicada and Ingenieria Quimica, Universidad de Malaga (Spain)

2013-02-15

Indium (III) oxide (In{sub 2}O{sub 3}) thin films have been obtained after heat treatment of In(OH){sub 3} precursor layers grown by a potential cycling electrodeposition (PCED) method from a dimethylsulfoxide (DMSO) based electrolytic solution onto fluorine-doped tin oxide (FTO) coated glass substrates. X-ray diffraction (XRD) measurements indicate the formation of a polycrystalline In{sub 2}O{sub 3} phase with a cubic structure. Scanning electron microscopy (SEM) and atomic force microscopy (AFM) showed a smooth morphology of the In{sub 2}O{sub 3} thin films after an optimized heat treatment had been developed. The surface composition and chemical state of the semiconductor films was established by X-ray photoelectron spectroscopy analysis. The nature of the semiconductor material, flat band potential and donor density were determined from Mott-Schottky plots. This study reveals that the In{sub 2}O{sub 3} films exhibited n-type conductivity with an average donor density of 2.2 x 10{sup 17} cm{sup -3}. The optical characteristics were determined through transmittance spectra. The direct and indirect band gap values obtained are according to the accepted values for the In{sub 2}O{sub 3} films of 2.83 and 3.54 eV for the indirect and direct band gap values. (Copyright copyright 2013 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Interfacially enhancement of PBO/epoxy composites by grafting MWCNTs onto PBO surface through melamine as molecular bridge

Science.gov (United States)

Lv, Junwei; Wang, Bin; Ma, Qi; Wang, Wenjing; Xiang, Dong; Li, Mengyao; Zeng, Lan; Li, Hui; Li, Yuntao; Zhao, Chunxia

2018-06-01

Melamine and multi-walled carbon nanotubes (MWCNTs) were grafted onto Poly-p-phenylene benzobisoxazole (PBO) fiber surface effectively via layer-by-layer method. Both of them have been chemically bonded as fourier transform infrared spectroscopy (FTIR) confirmed. Grafting melamine overcame the inertness of PBO surface. Ammoniation was processed on PBO surface through grafting melamine so that the MWCNTs could be grafted onto PBO surface. Scanning electron microscopy (SEM) images indicated that melamine used as molecular bridge could increase MWCNTs’ quantity on PBO surface. X-ray photoelectron spectroscopy (XPS) results revealed the variation of chemical composition of PBO surface. Test of interfacial shear strength (IFSS) and tensile strength indicated the great mechanical properties of modified PBO fibers when combining with epoxy resin. Furthermore, whole reaction was processed under a simple condition. Results in this research also promised a potential method to modify PBO surface.

Fabrication of a nano-structured PbO2 electrode by using printing technology: surface characterization and application

International Nuclear Information System (INIS)

Kannan, K.; Muthuraman, G.; Cho, G.; Moon, I. S.

2014-01-01

This investigation aimed to introduce printing technology for the first time to prepare a nanostrucutured PbO 2 electrode and its application to a cerium redox transfer process. The new method of nano-size PbO 2 preparation demonstrated that nano-PbO 2 could be obtained in less time and at less cost at room temperature. The prepared nano-PbO 2 screen printed on a Ti electrode by three different compositions under similar conditions showed through surface and electrochemical analyses no adherence on Ti and no contact with other nano-PbO 2 particles. Gravure printing of nano-PbO 2 on a PET (poly ethylene thin) film at high pressure was done with two different compositions for the first time. The selective composition of 57.14 % nano-PbO 2 powder with 4.28 % carbon black and 38.58 % ECA (ethyl carbitol acetate) produced a film with a nanoporous structure with an electron transfer ability. Finally, the optimized gravure-printed nano-PbO 2 electrode was applied to the oxidation of Ce(III) to Ce(IV) by using cyclic voltammetry. The gravure-printed nano-PbO 2 should pave the way to promising applications in electrochemical and sensor fields.

Structural aspects of B2O3-substituted (PbO)0.5(SiO2)0.5 glasses

International Nuclear Information System (INIS)

Sudarsan, V.; Kulshreshtha, S.K.; Shrikhande, V.K.; Kothiyal, G.P.

2002-01-01

Lead borosilicate glasses having general formulae (PbO) 0.5-x (SiO 2 ) 0.5 (B 2 O 3 ) x with 0.0≤x≤0.4 and (PbO) 0.5 (SiO 2 ) 0.5-y (B 2 O 3 ) y with 0.0≤y≤0.5 have been prepared by a conventional melt-quench method and characterized by 29 Si, 11 B magic angle spinning (MAS) NMR techniques and infrared spectroscopy, as regards their structural features. From 29 Si NMR results, it has been inferred that with increasing concentration of boron oxide, (PbO) 0.5-x (SiO 2 ) 0.5 (B 2 O 3 )x glasses exhibit a systematic increase in the number of Q 4 structural units of Si at the expense of Q 2 structural units, along with the formation of Si-O-B linkages. On the other hand, for (PbO) 0.5 (SiO 2 ) 0.5-y (B 2 O 3 ) y glasses, there is no direct interaction between SiO 2 and B 2 O 3 in the glass network, as revealed by the 29 Si MAS NMR studies. Boron exists in both trigonal and tetrahedral configurations for these two series of glasses and for the (PbO) 0.5 (SiO 2 ) 0.5-y (B 2 O 3 ) y series of glasses; the relative concentration of these two structural units remains almost constant with increasing B 2 O 3 concentration. In contrast, for (PbO) 0.5-x (SiO 2 ) 0.5 (B 2 O 3 ) x glasses, there is a slight increase in the number of BO 3 structural units above x = 0.2, as there is a competition between SiO 2 and B 2 O 3 for interaction with Pb 2+ , thereby leading to the formation of BO 3 structural units. For both series of glasses, the thermal expansion coefficient is found to decrease with increasing B 2 O 3 concentration, the effect being more pronounced for the (PbO) 0.5-x (SiO 2 ) 0.5 (B 2 O 3 ) x series of glasses due to the increased concentration of Q 4 structural units of silicon and better cross-linking as a result of the formation of Si-O-B-type linkages. (author)

Preparation of 235U target by electrodeposition

International Nuclear Information System (INIS)

Chen Qiping; Zhong Wenbin; Li Yougen

2004-12-01

A target for the production of fission 99 Mo in a nuclear reactor is composed of an enclosed, cylindrical vessel. Preferable vessel is comprised of stainless steel, having a thin, continuous, uniform layer of 235 U integrally bonded to its inner walls. Two processes are introduced for electrodepositing uranium on to the inner walls of the vessel. One processes is electrodepositing UO 2 from UO 2 (NO 3 ) 2 -(NH 4 ) 2 CO 4 ·H 2 O solution; the other is electrodepositing pure uranium metal from molten salt. Its plating efficiency and plating quantity from a molten bath is higher than UO 2 from the aqueous system. (authors)

Adsorption of organic layers over electrodeposited magnetite (Fe3O4) thin films

International Nuclear Information System (INIS)

Cortes, M.; Gomez, E.; Sadler, J.; Valles, E.

2011-01-01

Research highlights: → Adherent low roughness magnetite films ranging from 80 nm to 3.75 μm-thick were electrodeposited on Au/glass substrates under galvanostatic control. → X-ray diffraction and magnetic measurements corroborates the purity of the electrodeposited magnetite. → Both dodecanethiol and oleic acid are shown to adsorb on the magnetite prepared at low temperature, significantly inducing the hydrophobicity of the surface. → Contact angle and voltammetric measurements, as well as XPS confirm the monolayers formation. - Abstract: The formation of monolayers of two organic compounds (oleic acid and dodecanethiol) over magnetite films was studied. Magnetite films ranging from 80 nm to 3.75 μm-thick were electrodeposited on Au on glass substrates under galvanostatic control, with deposition parameters optimized for minimum surface roughness. Films were characterised by SEM and AFM, showing granular deposits with a low rms roughness of 5-40 nm measured over an area of 1 μm 2 . The growth rate was estimated by measuring cross-sections of the thin films. Pure magnetite with an fcc structure is observed in XRD diffractograms. The adsorption of both oleic acid and dodecanethiol on the magnetite films was tested by immersing them in ethanol solutions containing the organic molecules, for different deposition time, temperature and cleaning procedure. Monolayer formation in both cases was studied by contact angle and voltammetric measurements, as well as XPS.

Characterization of thin CeO{sub 2} films electrochemically deposited on HOPG

Energy Technology Data Exchange (ETDEWEB)

Faisal, Firas [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany); Toghan, Arafat, E-mail: arafat.toghan@yahoo.com [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany); Chemistry Department, Faculty of Science, South Valley University, 83523 Qena (Egypt); Khalakhan, Ivan; Vorokhta, Mykhailo; Matolin, Vladimír [Department of Surface and Plasma Science, Charles University in Prague, V Holešovičkách 747/2, 180 00 Prague 8 (Czech Republic); Libuda, Jörg [Lehrstuhl für Physikalische Chemie II, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany); Erlangen Catalysis Resource Center, Friedrich-Alexander-Universität Erlangen-Nürnberg, Egerlandstrasse 3, 91058 Erlangen (Germany)

2015-09-30

Graphical abstract: - Highlights: • Preparation of proton exchange membrane fuel cells catalyst using electrochemical thin film deposition. • Electrodeposition thin films of CeO{sub 2} on HOPG substrates. • The samples were characterized by in-situ AFM and ex-situ XPS. • XPS results reveal that the electrochemically deposited cerium oxide films are stoichiometric. • Exposing the films to ambient air, cracking structures are formed. - Abstract: Electrodeposition is widely used for industrial applications to deposit thin films, coatings, and adhesion layers. Herein, CeO{sub 2} thin films were deposited on a highly oriented pyrolytic graphite (HOPG) substrate by cathodic electrodeposition. The influence of the deposition parameters on the yield and on the film morphology is studied and discussed. Morphology and composition of the electrodeposited films were characterized by in-situ atomic force microscopy (AFM), scanning electron microscopy (SEM), Energy Dispersive X-ray spectroscopy (EDX), and X-ray photoelectron spectroscopy (XPS). By AFM we show that the thickness of CeO{sub 2} films can be controlled via the Ce{sup 3+} concentration in solution and the deposition time. After exposing the films to ambient air, cracking structures are formed, which were analyzed by AFM in detail. The chemical composition of the deposits was analyzed by XPS indicating the formation of nearly stoichiometric CeO{sub 2}.

CATHODIC ELECTRODEPOSITION OF Cu 4 SnS 4 THIN FILMS FROM ACIDIC SOLUTION

Directory of Open Access Journals (Sweden)

Anuar Kassim

2017-11-01

Full Text Available In this work the synthesis of copper tin sulfide thin films by electrodeposition is carried out. The films were deposited onto ITO glass substrates from anaqueous solution bath containingcopper sulfate, tin chloride and sodium thiosulfate at pH 1 and room temperature. Prior to the deposition, a cyclic voltammetry experiment was carried out between two potential limits (+1000 to -1000 mV versus Ag/AgCl to probe the effect of the applied potential and to determine the most likely suitable electrodeposition potential for the deposition of copper tin sulfide. The deposition was attempted at various cathodic potentials such as -400, -600, -800, -1000 mV to determine the optimum deposition potential. The films have been characterized by techniques such as optical absorption, X-ray diffraction and atomic force microscopy. The XRD patterns show that the films are polycrystalline with orthorhombic structure. The AFMstudies reveal the electrodeposited films were smooth, compact and uniform at deposition potentials of –600 mV versus Ag/AgCl. The direct optical band-gap energy was obtained to be 1.58 eV.

Preparation of uranium electrodeposited target in aqueous system

International Nuclear Information System (INIS)

Chen Qiping; Li Yougen; Zhong Wenbin

2006-03-01

The main factors affecting uranium electrodeposition were tested and discussed. In the primary experiment about preparation of uranium isotopic target by electrodeposition, a stainless steel disk has been chosen as the target material, the electrolytic bath is comprised of UO 2 (NO 3 ) 2 and (NH 4 ) 2 C 2 O 4 , which has been adjusted to a pH of 2-3. Composition of the lost electrolytic bath was analysed by spectrophotometer. The thickness of resulting film is about 8-10 mg/cm 2 , the target having a thin, continuous, uniform layer of uranium, and its electrodeposited rate is more than 80%. (authors)

Selective formation of biphasic thin films of metal–organic frameworks by potential-controlled cathodic electrodeposition

OpenAIRE

Li, Minyuan Miller; Dinca, Mircea

2013-01-01

Cathodic electrodeposition lends itself to the formation of biphasic metal–organic framework thin films at room temperature from single deposition baths using potential bias as the main user input. Depending on the applied potential, we selectively deposit two different phases as either bulk mixtures or bilayer films.

Preparation of uranium electrodeposited target in aqueous system

Energy Technology Data Exchange (ETDEWEB)

Qiping, Chen; Yougen, Li; Wenbin, Zhong [China Academy of Engineering Physics, Mianyang (China). Inst. of Nuclear Physics and Chemistry

2006-03-15

The main factors affecting uranium electrodeposition were tested and discussed. In the primary experiment about preparation of uranium isotopic target by electrodeposition, a stainless steel disk has been chosen as the target material, the electrolytic bath is comprised of UO{sub 2}(NO{sub 3}){sub 2} and (NH{sub 4}){sub 2}C{sub 2}O{sub 4}, which has been adjusted to a pH of 2-3. Composition of the lost electrolytic bath was analysed by spectrophotometer. The thickness of resulting film is about 8-10 mg/cm{sup 2}, the target having a thin, continuous, uniform layer of uranium, and its electrodeposited rate is more than 80%. (authors)

CATHODIC ELECTRODEPOSITION OF Cu 4 SnS 4 THIN FILMS FROM ACIDIC SOLUTION

Directory of Open Access Journals (Sweden)

Anuar Kassim

2017-11-01

Full Text Available In this work the synthesis of copper tin sulfide thin films by electrodeposition is carried out. The films were deposited onto ITO glass substrates from an aqueous solution bath containing copper sulfate, tin chloride and sodium thiosulfate at pH 1 and room temperature. Prior to the deposition, a cyclic voltammetry experiment was carried out  between two potential limits (+1000 to -1000 mV versus Ag/AgCl to probe the effect of  the applied potential and to determine the most likely suitable electrodeposition potential  for the deposition of copper tin sulfide. The deposition was attempted at various cathodic potentials such as -400, -600, -800, -1000 mV to determine the optimum deposition  potential. The films have been characterized by techniques such as optical absorption, Xray diffraction  and  atomic  force  microscopy. The XRD patterns show that the films are polycrystalline with orthorhombic structure. The AFM studies reveal the electrodeposited films were smooth, compact and uniform at deposition potentials of –600 mV versus  Ag/AgCl. The direct optical band-gap energy was obtained to be 1.58 eV.

OXIDACIÓN ELECTROQUÍMICA DE LAMBDACIALOTRINA SOBRE ELECTRODOS DE PBO2-BI

Directory of Open Access Journals (Sweden)

Leonardo Cifuentes

2015-09-01

Full Text Available The electrochemical oxidation of lambdacyhalotrin in a triton X-100 water solution on a PbO2-Bi electrode has been studied. It was discovered that electrocatalytic degradation proceeded through the Langmuir-Hinshelwood (L-H mechanism. The Langmuir adsorption equilibrium constant of the organic compound on the PbO2-Bi surface (0.67 (±0.02 mg-1L and the L-H maximum reaction rate for lambdacyhalotrin oxidation (0.040 (±0.002 mg L-1 min-1 was also determined on the basis of kinetic data. Oxidation/mineralization was tested at electrode potential higher than 2.3 V vs. Ag/AgCl, in this conditions the higher degradation percent of 85 (±4 % has been obtained.

Effects of Preparation Conditions on the CuInS2 Films Prepared by One-Step Electrodeposition Method

Directory of Open Access Journals (Sweden)

Rongfeng Guan

2015-01-01

Full Text Available CuInS2 thin films were prepared onto indium tin oxide (ITO substrates by sulfurization of electrodeposited CuxInySz precursor films under S atmosphere. The influences of deposition potential, Cu2+/In3+ ratio, sulfurization temperature, and sulfur content on the CuInS2 thin films were investigated. Phases and structures were characterized by powder X-ray diffraction and Raman spectroscopy; surface morphology was characterized by Scanning Electron Microscopy; optical and electrical properties were characterized by UV-Vis absorption and Mott-Schottky curves, respectively. As a result, the optimal well-crystallized CuInS2 films preparation parameters were determined to be deposition potential of −0.8 V, Cu2+/In3+ ratio of 1.4, sulfur content of 1 g, and the sulfurization temperature of 550°C for 1 h; CuInS2 thin films prepared by one-step electrodeposition present the p-type semiconductor, with thickness about 4-5 μm and their optical band gaps in the range of 1.53~1.55 eV.

Low-temperature preparation of crystalline nanoporous TiO2 films by surfactant-assisted anodic electrodeposition

Czech Academy of Sciences Publication Activity Database

Wessels, K.; Feldhoff, A.; Wark, M.; Rathouský, Jiří; Oekermann, T.

2006-01-01

Roč. 9, č. 6 (2006), C93-C96 ISSN 1099-0062 Institutional research plan: CEZ:AV0Z40400503 Keywords : thin films * cathodic electrodeposition * phase-stability * ZnO films Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.009, year: 2006

Comparative study of silicate glasses containing Bi2O3, PbO and BaO: Radiation shielding and optical properties

International Nuclear Information System (INIS)

Kirdsiri, K.; Kaewkhao, J.; Chanthima, N.; Limsuwan, P.

2011-01-01

Research highlights: → We change Bi 2 O 3 , PbO and BaO concentration in silicate glasses. → The densities of Bi 2 O 3 glasses more than PbO glasses and BaO glasses. → The Um of Bi 2 O 3 glasses and PbO glasses are comparable and more than BaO glasses. → This suggests that Bi 2 O 3 can replace PbO in radiation shielding glasses. - Abstract: The radiation shielding and optical properties of xBi 2 O 3 :(100-x)SiO 2 , xPbO:(100-x)SiO 2 and xBaO:(100-x)SiO 2 glass systems (where 30 ≤ x ≤ 70 is the composition by weight%) have been investigated. Total mass attenuation coefficients (μ m ) of glasses at 662 keV were improved by increasing their Bi 2 O 3 and PbO content, which raised the photoelectric absorption in glass matrices. Raising the BaO content to the same fraction range, however, brought no significant change to μ m . These results indicate that photon is strongly attenuated in Bi 2 O 3 and PbO containing glasses, and but not in BaO containing glass. The results from the optical absorption spectra show an edge that was not sharply defined; clearly indicating the amorphous nature of glass samples. It is observed that the cutoff wavelength for Bi 2 O 3 containing glass was longer than PbO and BaO containing glasses.

The influence of different electrodeposition E/t programs on the photoelectrochemical properties of α-Fe2O3 thin films

International Nuclear Information System (INIS)

Schrebler, Ricardo S.; Altamirano, Hernan; Grez, Paula; Herrera, Francisco V.; Munoz, Eduardo C.; Ballesteros, Luis A.; Cordova, Ricardo A.; Gomez, Humberto; Dalchiele, Enrique A.

2010-01-01

In this work morphological, structural and photoelectrochemical properties of n-type α-Fe 2 O 3 (hematite) thin films synthetized by means of two different electrochemical procedures: potential cycling electrodeposition (PC) and potential pulsed electrodeposition (PP) have been studied. The X-ray diffraction measurements showed that the films obtained after a thermal treatment at 520 o C present a nanocrystalline character. Scanning electron microscopy allowed finding that hematite films obtained by PP technique exhibit nanostructured morphology. The electrochemical and capacitance (Mott-Schottky and parallel capacitance) measurements showed that when in the PC and PP procedures the anodic limit E λ,A is being made more anodic, a decrease of the majority carriers concentration (N D ) and the surface states number has been observed. The photovoltammetry measurements indicated that the hematite films formed with the PP technique present a photocurrent one order of magnitude higher than the ones exhibited by the iron oxide films formed by PC. For instance, PP hematite films exhibit photovoltaic conversion efficiencies of 0.96% which are 2.5 times higher than the corresponding to the PC ones (0.38%). The maximum incident photon-to-current efficiency measured at λ = 370 and 600 nm was observed for hematite films grown by the PP procedure. By means of the photocurrent transient technique a decrease in the recombination process for those samples synthesized by PP was observed. The results obtained are discussed considering the influence of the anodic limit of the potential employed during the preparation of the iron oxyhydroxide (β-FeOOH) precursor film, all of this related to a decrease of the oxygen defects in this material and to a decrease of Fe(II) amount that is formed during the electrodeposition process.

Porous quasi three-dimensional nano-Mn3O4 + PbO2 composite as supercapacitor electrode material

International Nuclear Information System (INIS)

Dan Yuanyuan; Lin Haibo; Liu Xiaolei; Lu Haiyan; Zhao Jingzhe; Shi Zhan; Guo Yupeng

2012-01-01

Highlights: ► We prepare nano-PbO 2 + Mn 3 O 4 composite material by composite deposition method. ► The nano-PbO 2 + Mn 3 O 4 composite has porous quasi three-dimensional structure. ► Maximum electrochemically effective area (R F ) of the composite is 72. ► The composite shows high specific capacitance up to ∼340 F g −1 . ► A general knowledge of the pesudocapacitance behavior of the composite is acquired. - Abstract: Nano-Mn 3 O 4 + PbO 2 composite electrode materials with different compositions are prepared by anodic composite electrodeposition in Pb 2+ plating solution containing suspended nano-Mn 3 O 4 particles (40–60 nm). The particles are synthesized via one-step homogeneous precipitation at low temperature. The composite materials are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and scanning electron microscopy (SEM) analyses. The results indicate that the composite composed of γ-Mn 3 O 4 and β-PbO 2 is porous and quasi three-dimensional (3D), and its maximum electrochemically effective area ratio (R F ) is 72. The capacitance performance of the composite is determined by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and charge–discharge test. The composite shows a high specific capacitance up to 338 F g −1 .

A study on the electrodeposition of NiFe alloy thin films using chronocoulometry and electrochemical quartz crystal microgravimetry

CERN Document Server

Myung, N S

2001-01-01

Ni, Fe and NiFe alloy thin films were electrodeposited at a polycrystalline Au surface using a range of electrolytes and potentials. Coulometry and EQCM were used for real-time monitoring of electroplating efficiency of the Ni and Fe. The plating efficiency of NiFe alloy thin films was computed with the aid of ICP spectrometry. In general, plating efficiency increased to a steady value with deposition time. Plating efficiency of Fe was lower than that of Ni at -0.85 and -1.0 V but the efficiency approached to the similar plateau value to that of Ni at more negative potentials. The films with higher content of Fe showed different stripping behavior from the ones with higher content of Ni. Finally, compositional data and real-time plating efficiency are presented for films electrodeposited using a range of electrolytes and potentials.

Electrodeposition of Cu-In alloys for preparing CuInS sub 2 thin films

Energy Technology Data Exchange (ETDEWEB)

Herrero, J; Ortega, J [Inst. de Energias Renovables (CIEMAT), Madrid (Spain)

1990-01-01

Copper-indium alloys were prepared by electroplating from citric acid (C{sub 6}H{sub 8}O{sub 7}.H{sub 2}O) baths onto Ti substrate. Formation of the alloys was carried out by direct codeposition of the elements and by sequential electrodeposition of copper and indium. Studies of the alloy formation by electrochemical measurements and X-ray diffraction were performed. The presence of Cu{sub 7}In{sub 4} in direct deposit as well as in sequentially electrodeposited material was observed during the alloy formation. The as-deposited layers were heated in H{sub 2}S. X-ray diffraction showed the annealed layers to be CuInS{sub 2} with the chalcopyrite structure, where the CuIn{sub 5}S{sub 8} phase was included during the annealing process. Photoelectrochemical characterization of the samples allowed us to determine the photoconductivity which is related with the Cu/In ratio in the samples. The energy gap for CuInS{sub 2} photoelectrodes in polysulphide solution was 1.57 Ev. (orig.).

Electrical and magnetic properties of electrodeposited nickel incorporated diamond-like carbon thin films

Science.gov (United States)

Pandey, B.; Das, D.; Kar, A. K.

2015-05-01

Nanocomposite diamond-like carbon (DLC) thin films have been synthesized by incorporating nickel (Ni) nanoparticles in DLC matrix with varying concentration of nickel. DLC and Ni-DLC thin films have been deposited on ITO coated glass substrates employing low voltage electrodeposition method. Electrical properties of the samples were studied by measuring current-voltage characteristics and dielectric properties. The current approaches toward an ohmic behavior with metal addition. This tendency of increasing ohmicity is enhanced with increase in dilution of the electrolyte. The conductivity increases with Ni addition and interestingly it continues to increase with dilution of Ni concentration in the electrolyte in the range of our study. Magnetic properties for DLC and Ni-DLC thin film samples were examined by electron paramagnetic resonance (EPR) measurements and Super Conducting Quantum Interference Device (SQUID) measurements. g-Value for DLC is 2.074, whereas it decreases to 2.055 with Ni addition in the electrolyte. This decrement arises from the increased sp2 content in DLC matrix. The magnetic moment vs. magnetic field (m-H) curves of Ni-DLC indicate superparamagnetic behavior which may be due to ferromagnetic contribution from the incorporated nickel nanoparticles in the DLC matrix. The ZFC curve of Ni-DLC after the blocking temperature shows a combined contribution of ferromagnetic, superparamagnetic and paramagnetic nature of the materials persisting up to 300 K.

Electrochemical disinfection of simulated ballast water on PbO2/graphite felt electrode

International Nuclear Information System (INIS)

Chen, Shuiping; Hu, Weidong; Hong, Jianxun; Sandoe, Steve

2016-01-01

A novel PbO 2 /graphite felt electrode was constructed by electrochemical deposition of PbO 2 on graphite felt and characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) analysis. The prepared electrode is a viable technology for inactivation of Escherichia coli, Enterococcus faecalis, and Artemia salina as indicator organisms in simulated ballast water treatment, which meets the International Maritime Organization (IMO) Regulation D-2. The effects of contact time and current density on inactivation were investigated. An increase in current density generally had a beneficial effect on the inactivation of the three species. E.faecalis and A.salina were more resistant to electrochemical disinfection than E. coli. The complete disinfection of E.coli was achieved in <8 min at an applied current density of 253 A/m 2 . Complete inactivation of E. faecalis and A.salina was achieved at the same current density after 60 and 40 min of contact time, respectively. A. salina inactivation follows first-order kinetics. - Highlights: •A novel PbO 2 /graphite felt anode was developed for the electrochemical treatment of the simulated ballast water. •The technology meets the IMO D‐2 regulation and provides a high degree of removal of the microorganisms of ballast water without any additional chemical substances. •E.faecalis, E.coli, and A.salina cells in simulated ballast water were completely inactivated after 60, 8 and 40 min of contact time at 253 A/m 2 of current density, respectively.

Structural, optical and electrical properties of CeO2 thin films simultaneously prepared by anodic and cathodic electrodeposition

Science.gov (United States)

Yang, Yumeng; Du, Xiaoqing; Yi, Chenxi; Liu, Jiao; Zhu, Benfeng; Zhang, Zhao

2018-05-01

CeO2 thin films were deposited on stainless steel (SS) and indium tin oxide (ITO)-coated glass by simultaneous anodic and cathodic electrodeposition, and the influence of negative potential on the formation of ceria films was studied with scanning electron microscopy, X-ray diffraction, Raman spectroscopy, van der Pauw measurements, UV-visible spectroscopy and X-ray photoelectron spectroscopy. The results show that CeO2 films on the anode are slightly affected by the potential, but the particle size, crystal orientation, strain, film thickness, resistivity and Ce(III) content of the films on the cathode increases with increasing potential on the SS substrate. Contradictory to the results of the SS cathode, redshift (Ed changed from 3.95 eV to 3.56 eV and Ei changed from 3.42 eV to 3.04 eV) occurring in the absorption spectrum of CeO2 deposited on the ITO-coated glass cathode indicates that the content of Ce3+ in the cathodic films is dependent on the adopted substrates and decreases as the applied potential is increased.

Preparation of thin hexagonal highly-ordered anodic aluminum oxide (AAO) template onto silicon substrate and growth ZnO nanorod arrays by electrodeposition

Science.gov (United States)

Chahrour, Khaled M.; Ahmed, Naser M.; Hashim, M. R.; Elfadill, Nezar G.; Qaeed, M. A.; Bououdina, M.

2014-12-01

In this study, anodic aluminum oxide (AAO) templates of Aluminum thin films onto Ti-coated silicon substrates were prepared for growth of nanostructure materials. Hexagonally highly ordered thin AAO templates were fabricated under controllable conditions by using a two-step anodization. The obtained thin AAO templates were approximately 70 nm in pore diameter and 250 nm in length with 110 nm interpore distances within an area of 3 cm2. The difference between first and second anodization was investigated in details by in situ monitoring of current-time curve. A bottom barrier layer of the AAO templates was removed during dropping the voltage in the last period of the anodization process followed by a wet etching using phosphoric acid (5 wt%) for several minutes at ambient temperature. As an application, Zn nanorod arrays embedded in anodic alumina (AAO) template were fabricated by electrodeposition. Oxygen was used to oxidize the electrodeposited Zn nanorods in the AAO template at 700 °C. The morphology, structure and photoluminescence properties of ZnO/AAO assembly were analyzed using Field-emission scanning electron microscope (FESEM), Energy dispersive X-ray spectroscopy (EDX), Atomic force microscope (AFM), X-ray diffraction (XRD) and photoluminescence (PL).

Preparation and characterization of electrodeposited SnS:In thin films: Effect of In dopant

Science.gov (United States)

Kafashan, Hosein; Balak, Zohre

2017-09-01

SnS:In thin films were grown on fluorine doped tin oxide (FTO) substrate by cathodic electrodeposition technique. The solution was containing 2 mM SnCl2 and 16 mM Na2S2O3 and different amounts of 1 mM InCl3 as In-dopant. The pH, bath temperature, deposition time, and deposition potential (E) were fixed at 2.1, 60 °C, 30 min, and - 1 V, respectively. The XRD results showed that the synthesized films were polycrystalline orthorhombic SnS. The XPS results demonstrated that the films were composed of Sn, S and In. According to the FESEM images, an increase in In-dopant concentration leads to a change in morphology from grain-like to sheet-like having a nanoscale thickness of 20-80 nm and fiber-like. The PL spectra of undoped SnS exhibited four emission peaks including a UV peak, two blue emission peaks, and an IR emission peak. According to the UV-Vis spectra, the direct band gap of SnS:In thin films was estimated to be 1.40-1.66 eV.

Synthesis of shape memory alloys using electrodeposition

Science.gov (United States)

Hymer, Timothy Roy

Shape memory alloys are used in a variety of applications. The area of micro-electro-mechanical systems (MEMS) is a developing field for thin film shape memory alloys for making actuators, valves and pumps. Until recently thin film shape memory alloys could only be made by rapid solidification or sputtering techniques which have the disadvantage of being "line of sight". At the University of Missouri-Rolla, electrolytic techniques have been developed that allow the production of shape memory alloys in thin film form. The advantages of this techniques are in-situ, non "line of sight" and the ability to make differing properties of the shape memory alloys from one bath. This research focused on the electrodeposition of In-Cd shape memory alloys. The primary objective was to characterize the electrodeposited shape memory effect for an electrodeposited shape memory alloy. The effect of various operating parameters such as peak current density, temperature, pulsing, substrate and agitation were investigated and discussed. The electrodeposited alloys were characterized by relative shape memory effect, phase transformation, morphology and phases present. Further tests were performed to optimize the shape memory by the use of a statistically designed experiment. An optimized shape memory effect for an In-Cd alloy is reported for the conditions of the experiments.

Preparation of thin films, with base to precursor materials of type Cu-In-Se elaborated by electrodeposition for the solar cells elaboration

International Nuclear Information System (INIS)

Fernandez, A.M.

1999-01-01

Thin films of chalcogenide compounds are promising because they have excellent optoelectronic characteristics to be applied in solar cells. In particular, CuInSe 2 and Cd Te thin films have shown high solar to electrical conversion efficiency. However, this efficiency is limited by the method of preparation, in this case, physical vapor deposition techniques are used. In order to increase the area of deposition t is necessary to use chemical methods, for example, electrodeposition technique. In this paper, the preparation of Cu-In-Se precursors thin films by electrochemical method is reported. These precursors were used to build solar cells with 7.9 % of efficiency. (Author)

Electrochemical preparation and characterization of CuInSe2 thin films for photovoltaic applications

International Nuclear Information System (INIS)

Guillen Arqueros, C.

1992-01-01

The objective of this work has been to investigate the electrodeposition as a low-cost, large-area fabrication process to obtain CuInSe 2 this films for efficient photovoltaic devices. this objective entails the elucidation of thin film deposition mechanism, the study of the fundamental properties of electrodeposited material, and also the modification of their physical and chemical parameters for photovoltaic applications. CuInSe 2 thin films have been successfully electrodeposited from a citric was characterized by compositional, structural, electrical, optical and electrochemical measurements, relating their properties with the preparation parameters and also studying the effect of various thermal and chemical treatments. The results showed post-deposition treatment are needed for optimizing these films for solar cells fabrication: first, an annealing in inert atmosphere at temperatures above 400 degrees celsius to obtain a high recrystallization in the chalcopyrite structure, and after a chemical etching in KCN solution to remove secondary phases of Cu x Se and Se which are frequently electrodeposited with the CuInSe 2 . The treated samples showed appropriate photovoltaic activity in a semiconductor-electrolite liquid junction. (author) 193 ref

Electrodeposition and electrochemical characterisation of thick and thin coatings of Sb and Sb/Sb2O3 particles for Li-ion battery anodes

International Nuclear Information System (INIS)

Bryngelsson, Hanna; Eskhult, Jonas; Edstroem, Kristina; Nyholm, Leif

2007-01-01

The possibilities to electrodeposit thick coatings composed of nanoparticles of Sb and Sb 2 O 3 for use as high-capacity anode materials in Li-ion batteries have been investigated. It is demonstrated that the stability of the coatings depends on their Sb 2 O 3 concentrations as well as microstructure. The electrodeposition reactions in electrolytes with different pH and buffer capacities were studied using chronopotentiometry and electrochemical quartz crystal microbalance measurements. The obtained deposits, which were characterised with XRD and SEM, were also tested as anode materials in Li-ion batteries. The influence of the pH and buffer capacity of the deposition solution on the composition and particle size of the deposits were studied and it is concluded that depositions from a poorly buffered solution of antimony-tartrate give rise to good anode materials due to the inclusion of precipitated Sb 2 O 3 nanoparticles in the Sb coatings. Depositions under conditions yielding pure Sb coatings give rise to deposits composed of large crystalline particles with poor anode stabilities. The presence of a plateau at about 0.8 V versus Li + /Li due to SEI forming reactions and the origin of another plateau at about 0.4 V versus Li + /Li seen during the lithiation of thin Sb coatings are also discussed. It is demonstrated that the 0.4 V plateau is present for Sb coatings for which the (0 1 2) peak is the main peak in the XRD diffractogram

Electrical and magnetic properties of electrodeposited nickel incorporated diamond-like carbon thin films

Energy Technology Data Exchange (ETDEWEB)

Pandey, B., E-mail: pandey.beauty@yahoo.com [Department of Applied Physics, Indian School of Mines, Dhanbad 826004 (India); Das, D. [UGC-DAE CSR, Sector III/LB-8, Bidhan Nagar, Kolkata 700098 (India); Kar, A.K. [Department of Applied Physics, Indian School of Mines, Dhanbad 826004 (India)

2015-05-15

Highlights: • Electrical and magnetic properties of DLC and Ni-DLC thin films are studied. • The ohmicity and conductivity of DLC films rise with nickel addition. • The ohmicity of Ni-DLC is enhanced with increase in dilution of electrolyte. • Dielectric loss is high for Ni-DLC and decreases with frequency till 100 kHz. • (m–H) and (m–T) curves of Ni-DLC indicate superparamagnetic behavior. - Abstract: Nanocomposite diamond-like carbon (DLC) thin films have been synthesized by incorporating nickel (Ni) nanoparticles in DLC matrix with varying concentration of nickel. DLC and Ni-DLC thin films have been deposited on ITO coated glass substrates employing low voltage electrodeposition method. Electrical properties of the samples were studied by measuring current–voltage characteristics and dielectric properties. The current approaches toward an ohmic behavior with metal addition. This tendency of increasing ohmicity is enhanced with increase in dilution of the electrolyte. The conductivity increases with Ni addition and interestingly it continues to increase with dilution of Ni concentration in the electrolyte in the range of our study. Magnetic properties for DLC and Ni-DLC thin film samples were examined by electron paramagnetic resonance (EPR) measurements and Super Conducting Quantum Interference Device (SQUID) measurements. g-Value for DLC is 2.074, whereas it decreases to 2.055 with Ni addition in the electrolyte. This decrement arises from the increased sp{sup 2} content in DLC matrix. The magnetic moment vs. magnetic field (m–H) curves of Ni-DLC indicate superparamagnetic behavior which may be due to ferromagnetic contribution from the incorporated nickel nanoparticles in the DLC matrix. The ZFC curve of Ni-DLC after the blocking temperature shows a combined contribution of ferromagnetic, superparamagnetic and paramagnetic nature of the materials persisting up to 300 K.

Studying the initial stages of film electrodeposition of magnetic cobalt-tungsten alloys

International Nuclear Information System (INIS)

Rachinskas, V.S.; Orlovskaya, L.V.; Parfenov, V.A.; Yasulajtene, V.V.

1996-01-01

Initial stages of magnetic film electrodeposition by recording potentiodynamic polarization and j c ,t-curves, determination of surface structure of electrolytically deposited films by the method of XPS and study of thin coating properties have been considered. It is shown that at initial stage of electrodeposition of magnetic Co-W-films a sharp decrease in cathode process rate and formation of Co(OH) 2 , WO 3 and/or WO 4 2- occur on Cu-cathode surface. Electrodeposition of metallic magnetic Co-W-alloy, consisting of Co, W and containing basic compounds of co-deposited metals, takes place after a certain time period depending on deposition E c . 6 refs.; 3 figs

Electrochemical disinfection of simulated ballast water on PbO2/graphite felt electrode.

Science.gov (United States)

Chen, Shuiping; Hu, Weidong; Hong, Jianxun; Sandoe, Steve

2016-04-15

A novel PbO2/graphite felt electrode was constructed by electrochemical deposition of PbO2 on graphite felt and characterized by X-ray powder diffraction (XRD) and scanning electron microscopy (SEM) analysis. The prepared electrode is a viable technology for inactivation of Escherichia coli, Enterococcus faecalis, and Artemia salina as indicator organisms in simulated ballast water treatment, which meets the International Maritime Organization (IMO) Regulation D-2. The effects of contact time and current density on inactivation were investigated. An increase in current density generally had a beneficial effect on the inactivation of the three species. E.faecalis and A.salina were more resistant to electrochemical disinfection than E. coli. The complete disinfection of E.coli was achieved in <8min at an applied current density of 253A/m(2). Complete inactivation of E. faecalis and A.salina was achieved at the same current density after 60 and 40min of contact time, respectively. A. salina inactivation follows first-order kinetics. Copyright © 2016 Elsevier Ltd. All rights reserved.

Solar cells based on electrodeposited thin films of ZnS, CdS, CdSSe and CdTe

Science.gov (United States)

Weerasinghe, Ajith R.

The motivations of this research were to produce increased efficiency and low-cost solar cells. The production efficiency of Si solar cells has almost reached their theoretical limit, and reducing the manufacturing cost of Si solar cells is difficult to achieve due to the high-energy usage in material purifying and processing stages. Due to the low usage of materials and input energy, thin film solar cells have the potential to reduce the costs. CdS/CdTe thin film solar cells are already the cheapest on $/W basis. The cost of CdTe solar cells can be further reduced if all the semiconducting layers are fabricated using the electrodeposition (ED) method. ED method is scalable, low in the usage of energy and raw materials. These benefits lead to the cost effective production of semiconductors. The conventional method of fabricating CdS layers produces Cd containing waste solutions routinely, which adds to the cost of solar cells.ZnS, CdS and CdS(i-X)Sex buffer and window layers and CdTe absorber layers have been successfully electrodeposited and explored under this research investigation. These layers were fully characterised using complementary techniques to evaluate the material properties. Photoelectrochemical (PEC) studies, optical absorption, X-ray diffraction (XRD), X-ray fluorescence (XRF), scanning electron microscopy (SEM), energy-dispersive X-ray (EDX) spectroscopy, atomic force microscopy (AFM) and Raman spectroscopy were utilised to evaluate the material properties of these solid thin film layers. ZnS and CdS thin film layers were electrodeposited from Na-free chemical precursors to avoid the group I element (Na) to reduce deterioration of CdTe devices. Deposition parameters such as, growth substrates, temperature, pH, growth cathodic voltage, stirring rate, time and chemical concentrations were identified to fabricate the above semiconductors. To further optimise these layers, a heat treatment process specific to the material was developed. In addition

Dependency of the band gap of electrodeposited Copper oxide thin films on the concentration of copper sulfate (CuSO4.5H2O) and pH in bath solution for photovoltaic applications

KAUST Repository

Islam, Md. Anisul

2016-03-10

In this study, Copper oxide thin films were deposited on copper plate by electrodeposition process in an electrolytic bath containing CuSO4.5H2O, 3M lactic acid and NaOH. Copper oxide films were electrodeposited at different pH and different concentration of CuSO4.5H2O and the optical band gap was determined from their absorption spectrum which was obtained from UV-Vis absorption spectroscopy. It was found that copper oxide films which were deposited at low concentration of CuSO4.5H2O have higher band gap than those deposited at higher bath concentration. The band gap of copper oxide films also significantly changes with pH of the bath solution. It was also observed that with the increase of the pH of bath solution band gap of copper oxide film decreased. © 2015 IEEE.

Electrodeposited CuInS2 Using Dodecylbenzene Sulphonic Acid As a Suspending Agent for Thin Film Solar Cell

Directory of Open Access Journals (Sweden)

Shaker Ebrahim

2012-01-01

Full Text Available CulnS2 thin films were electrochemically deposited onto fluoride-doped tin oxide (FTO substrate in presence of dodecylbenzene sulphonic acid to adjust pH of the solution and as a suspending agent for the sulfur. Cyclic voltammetry and chronoamperometry were carried out to determine the optimum pH. The composition, crystallinity, and optical properties of the compounds synthesized were studied by energy dispersive X-ray (EDX, X-ray diffraction, and UV-Visible spectra. It was found that the increasing of pH shifts the electrodeposited voltage toward more negative and lowers the deposition current. It was concluded that CuInS2 with atomic stoichiometric ratio was prepared at pH equal to 1.5 and 150 ml of 0.1 M sodium thiosulphate, 5 ml of 0.1 M indium chloride, and 5 ml of 0.1 M cupper chloride. The energy gaps were calculated to be 1.95 and 2.2 eV for CuInS2 prepared at 1.5 and 2.5 of pH, respectively. It was found that sc, oc, and are 1.02×10−4 A/cm2, 0.52 V, and 1.3×10−2%, respectively, for FTO/CuInS2/ZnO/FTO heterojunction solar cell.

Effect of Deposition Time on the Photoelectrochemical Properties of Cupric Oxide Thin Films Synthesized via Electrodeposition Method

Directory of Open Access Journals (Sweden)

Yaw Chong Siang

2016-01-01

Full Text Available The main aim of this study was to investigate the effect of deposition time on the physicochemical and photoelectrochemical properties of cupric oxide (CuO thin films synthesized via electrodeposition method. Firstly, the electrodeposition of amorphous CuO films on fluorine-doped tin oxide (FTO working electrodes with varying deposition time between 5 and 30 min was carried out, followed by annealing treatment at 500 °C. Resultant nanocrystalline CuO thin films were characterised using field emission-scanning electron microscopy (FE-SEM, photocurrent density, and photoluminescence measurements. Through FE-SEM analysis, it was observed that the surface of thin films was composed of irregular-sized CuO nanocrystals. A smaller CuO nanocrystals size will lead to a higher photoactivity due to the increase in overall catalytic surface area. In addition, the smaller CuO nanocrystals size will prolongs the electron-hole recombination rate due to the increase in copious amount of surface defects. From this study, it was revealed that the relationship between deposition time and CuO film thickness was non-linear. This could be due to the detachment of CuO thin films from the FTO surface at an increasing amount of CuO mass being deposited. It was observed that the amount of light absorbed by CuO thin films increased with film thickness until a certain extent whereby, any further increase in the film thickness will result in a reduction of light photon penetration. Therefore, the CuO nanocrystals size and film thickness have to be compromised in order to yield a higher catalytic surface area and a lower rate of surface charge recombination. Finally, it was found that the deposition time of 15 min resulted in an average CuO nanocrystals size of 73.7 nm, optimum film thickness of 0.73 μm, and corresponding photocurrent density of 0.23 mA/cm2 at the potential bias of - 0.3 V (versus Ag/AgCl. The PL spectra for the deposition time of 15 min has the lowest

Phase-Change Memory Properties of Electrodeposited Ge-Sb-Te Thin Film

Science.gov (United States)

Huang, Ruomeng; Kissling, Gabriela P.; Jolleys, Andrew; Bartlett, Philip N.; Hector, Andrew L.; Levason, William; Reid, Gillian; De Groot, C. H. `Kees'

2015-11-01

We report the properties of a series of electrodeposited Ge-Sb-Te alloys with various compositions. It is shown that the Sb/Ge ratio can be varied in a controlled way by changing the electrodeposition potential. This method opens up the prospect of depositing Ge-Sb-Te super-lattice structures by electrodeposition. Material and electrical characteristics of various compositions have been investigated in detail, showing up to three orders of magnitude resistance ratio between the amorphous and crystalline states and endurance up to 1000 cycles.

Production and characterization of TI/PbO2 electrodes by a thermal-electrochemical method

Directory of Open Access Journals (Sweden)

Laurindo Edison A.

2000-01-01

Full Text Available Looking for electrodes with a high overpotential for the oxygen evolution reaction (OER, useful for the oxidation of organic pollutants, Ti/PbO2 electrodes were prepared by a thermal-electrochemical method and their performance was compared with that of electrodeposited electrodes. The open-circuit potential for these electrodes in 0.5 mol L-1 H2SO4 presented quite stable similar values. X-ray diffraction analyses showed the thermal-electrochemical oxide to be a mixture of ort-PbO, tetr-PbO and ort-PbO2. On the other hand, the electrodes obtained by electrodeposition were in the tetr-PbO2 form. Analyses by scanning electron microscopy showed that the basic morphology of the thermal-electrochemical PbO2 is determined in the thermal step, being quite distinct from that of the electrodeposited electrodes. Polarization curves in 0.5 mol L-1 H2SO4 showed that in the case of the thermal-electrochemical PbO2 electrodes the OER was shifted to more positive potentials. However, the values of the Tafel slopes, quite high, indicate that passivating films were possibly formed on the Ti substrates, which could eventually explain the somewhat low current values for OER.

Cathodic electrochemical deposition of Magnéli phases TinO2n−1 thin films at different temperatures in acetonitrile solution

International Nuclear Information System (INIS)

Ertekin, Zeliha; Tamer, Uğur; Pekmez, Kadir

2015-01-01

Highlights: • TiO x films were prepared by cathodic electrodeposition in acetonitrile. • One-step electrodeposition of TiO x films without heat treatment process. • Different crystalline Ti n O 2n−1 films (γTi 3 O 5 , λTi 3 O 5 , Ti 4 O 7 , Ti 5 O 9 ) were obtained. - Abstract: The Magnéli phase titanium oxide films prepared by cathodic electrodeposition on indium–tin-oxide coated glass substrates from saturated peroxo-titanium solution in acetonitrile. Electrodeposited brownish semi-conductor thin films were identified via X-ray diffraction, Raman spectroscopy, UV–vis spectroscopy and scanning electron microscopy (SEM). The effects of different potentials and temperatures on the crystallinity of the thin films have been discussed. Ti 3 O 5 , Ti 4 O 7 and Ti 5 O 9 as the most favorable forms of the Ti n O 2n−1 were electrodeposited on ITO electrode at electrochemical deposition potentials and different temperatures. The present investigation reveals that the electrochemical deposition of crystalline Ti n O 2n−1 films by a simple one-step electrodeposition method (without any heat treatment) in acetonitrile solution is possible and very promising as a preparation method for electrochemical applications

Electrodeposition route to synthesize cigs films – an economical way ...

African Journals Online (AJOL)

Electrodeposition route to synthesize cigs films – an economical way to harness solar energy. ... for solar cells, how the charge separation in this nano scale photovoltaic (PV) materials occurs which help in absorption of radiation, and the electro-deposition route, a low cost one, produces thin film solar cells are analyzed.

Room-temperature synthesis and characterization of porous CeO2 thin films

International Nuclear Information System (INIS)

Chu, Dewei; Masuda, Yoshitake; Ohji, Tatsuki; Kato, Kazumi

2012-01-01

CeO 2 thin films with hexagonal-shaped pores were successfully prepared by a facile electrodeposition at room temperature combined with an etching process. By using electrodeposited ZnO nanorods as a soft template, the morphology, and microstructure of the CeO 2 could be controlled. TEM observation indicated that as-prepared CeO 2 film is composed of nanocrystals with average size of several nanometers, while XPS analysis showed the coexistence of Ce 3+ and Ce 4+ in the film. The photoluminescence properties of CeO 2 films were measured, which showed much higher sensitivity compared to bare substrate. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Optimization of the Electrodeposition Parameters to Improve the Stoichiometry of In2S3 Films for Solar Applications Using the Taguchi Method

Directory of Open Access Journals (Sweden)

Maqsood Ali Mughal

2014-01-01

Full Text Available Properties of electrodeposited semiconductor thin films are dependent upon the electrolyte composition, plating time, and temperature as well as the current density and the nature of the substrate. In this study, the influence of the electrodeposition parameters such as deposition voltage, deposition time, composition of solution, and deposition temperature upon the properties of In2S3 films was analyzed by the Taguchi Method. According to Taguchi analysis, the interaction between deposition voltage and deposition time was significant. Deposition voltage had the largest impact upon the stoichiometry of In2S3 films and deposition temperature had the least impact. The stoichiometric ratios between sulfur and indium (S/In: 3/2 obtained from experiments performed with optimized electrodeposition parameters were in agreement with predicted values from the Taguchi Method. The experiments were carried out according to Taguchi orthogonal array L27 (3^4 design of experiments (DOE. Approximately 600 nm thick In2S3 films were electrodeposited from an organic bath (ethylene glycol-based containing indium chloride (InCl3, sodium chloride (NaCl, and sodium thiosulfate (Na2S2O3·5H2O, the latter used as an additional sulfur source along with elemental sulfur (S. An X-ray diffractometer (XRD, energy dispersive X-ray spectroscopy (EDS unit, and scanning electron microscope (SEM were, respectively, used to analyze the phases, elemental composition, and morphology of the electrodeposited In2S3 films.

Influences of magnetic field on the fractal morphology in copper electrodeposition

Science.gov (United States)

Sudibyo; How, M. B.; Aziz, N.

2018-01-01

Copper magneto-electrodeposition (MED) is used decrease roughening in the copper electrodeposition process. This technology plays a vital role in electrodeposition process to synthesize metal alloy, thin film, multilayer, nanowires, multilayer nanowires, dot array and nano contacts. The effects of magnetic fields on copper electrodeposition are investigated in terms of variations in the magnetic field strength and the electrolyte concentration. Based on the experimental results, the mere presence of magnetic field would result in a compact deposit. As the magnetic field strength is increased, the deposit grows denser. The increment in concentration also leads to the increase the deposited size. The SEM image analysis showed that the magnetic field has a significant effect on the surface morphology of electrodeposits.

Effects of atmospheric air plasma treatment on interfacial properties of PBO fiber reinforced composites

Energy Technology Data Exchange (ETDEWEB)

Zhang, Chengshuang, E-mail: cszhang83@163.com; Li, Cuiyun; Wang, Baiya; Wang, Bin; Cui, Hong

2013-07-01

Poly(p-phenylene benzobisoxazole) (PBO) fiber was modified by atmospheric air plasma treatment. The effects of plasma treatment power and speed on both surface properties of PBO fibers and interfacial properties of PBO/epoxy composites were investigated. Surface chemical composition of PBO fibers were analyzed by X-ray photoelectron spectroscopy (XPS). Surface morphologies of the fibers and interface structures of the composites were examined using scanning electron microscopy (SEM). Interfacial adhesion property of the composites was evaluated by interlaminar shear strength (ILSS). Mechanical properties of PBO multifilament were measured by universal testing machine. The results indicate that atmospheric air plasma treatment introduced some polar or oxygen-containing groups to PBO fiber surfaces, enhanced surface roughness and changed surface morphologies of PBO fibers by plasma etching and oxidative reactions. The plasma treatment also improved interfacial adhesion of PBO/epoxy composites but has little effect on tensile properties of PBO multifilament. The ILSS of PBO/epoxy composites increased to 40.0 MPa after atmospheric air plasma treatment with plasma treatment power of 300 W and treatment speed of 6 m/min.

Effects of annealing temperature on the physicochemical, optical and photoelectrochemical properties of nanostructured hematite thin films prepared via electrodeposition method

International Nuclear Information System (INIS)

Phuan, Yi Wen; Chong, Meng Nan; Zhu, Tao; Yong, Siek-Ting; Chan, Eng Seng

2015-01-01

Highlights: • Nanostructured hematite thin films were synthesized via electrodeposition method. • Effects of annealing on size, grain boundary and PEC properties were examined. • Photocurrents generation was enhanced when the thin films were annealed at 600 °C. • The highest photocurrent density of 1.6 mA/cm 2 at 0.6 V vs Ag/AgCl was achieved. - Abstract: Hematite (α-Fe 2 O 3 ) is a promising photoanode material for hydrogen production from photoelectrochemical (PEC) water splitting due to its wide abundance, narrow band-gap energy, efficient light absorption and high chemical stability under aqueous environment. The key challenge to the wider utilisation of nanostructured hematite-based photoanode in PEC water splitting, however, is limited by its low photo-assisted water oxidation caused by large overpotential in the nominal range of 0.5–0.6 V. The main aim of this study was to enhance the performance of hematite for photo-assisted water oxidation by optimising the annealing temperature used during the synthesis of nanostructured hematite thin films on fluorine-doped tin oxide (FTO)-based photoanodes prepared via the cathodic electrodeposition method. The resultant nanostructured hematite thin films were characterised using field emission-scanning electron microscopy (FE-SEM) coupled with energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV-visible spectroscopy and Fourier transform infrared spectroscopy (FTIR) for their elemental composition, average nanocrystallites size and morphology; phase and crystallinity; UV-absorptivity and band gap energy; and the functional groups, respectively. Results showed that the nanostructured hematite thin films possess good ordered nanocrystallites array and high crystallinity after annealing treatment at 400–600 °C. FE-SEM images illustrated an increase in the average hematite nanocrystallites size from 65 nm to 95 nm when the annealing temperature was varied from 400 °C to 600 °C. As the

Effects of annealing temperature on the physicochemical, optical and photoelectrochemical properties of nanostructured hematite thin films prepared via electrodeposition method

Energy Technology Data Exchange (ETDEWEB)

Phuan, Yi Wen [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 46150 Selangor DE (Malaysia); Chong, Meng Nan, E-mail: Chong.Meng.Nan@monash.edu [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 46150 Selangor DE (Malaysia); Sustainable Water Alliance, Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 46150 Selangor DE (Malaysia); Zhu, Tao; Yong, Siek-Ting [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 46150 Selangor DE (Malaysia); Chan, Eng Seng [School of Engineering, Chemical Engineering Discipline, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 46150 Selangor DE (Malaysia); Sustainable Water Alliance, Advanced Engineering Platform, Monash University Malaysia, Jalan Lagoon Selatan, Bandar Sunway 46150 Selangor DE (Malaysia)

2015-09-15

Highlights: • Nanostructured hematite thin films were synthesized via electrodeposition method. • Effects of annealing on size, grain boundary and PEC properties were examined. • Photocurrents generation was enhanced when the thin films were annealed at 600 °C. • The highest photocurrent density of 1.6 mA/cm{sup 2} at 0.6 V vs Ag/AgCl was achieved. - Abstract: Hematite (α-Fe{sub 2}O{sub 3}) is a promising photoanode material for hydrogen production from photoelectrochemical (PEC) water splitting due to its wide abundance, narrow band-gap energy, efficient light absorption and high chemical stability under aqueous environment. The key challenge to the wider utilisation of nanostructured hematite-based photoanode in PEC water splitting, however, is limited by its low photo-assisted water oxidation caused by large overpotential in the nominal range of 0.5–0.6 V. The main aim of this study was to enhance the performance of hematite for photo-assisted water oxidation by optimising the annealing temperature used during the synthesis of nanostructured hematite thin films on fluorine-doped tin oxide (FTO)-based photoanodes prepared via the cathodic electrodeposition method. The resultant nanostructured hematite thin films were characterised using field emission-scanning electron microscopy (FE-SEM) coupled with energy dispersive X-ray spectroscopy (EDX), X-ray diffraction (XRD), UV-visible spectroscopy and Fourier transform infrared spectroscopy (FTIR) for their elemental composition, average nanocrystallites size and morphology; phase and crystallinity; UV-absorptivity and band gap energy; and the functional groups, respectively. Results showed that the nanostructured hematite thin films possess good ordered nanocrystallites array and high crystallinity after annealing treatment at 400–600 °C. FE-SEM images illustrated an increase in the average hematite nanocrystallites size from 65 nm to 95 nm when the annealing temperature was varied from 400 °C to 600

Fabrication of mesoporous cerium dioxide films by cathodic electrodeposition.

Science.gov (United States)

Kim, Young-Soo; Lee, Jin-Kyu; Ahn, Jae-Hoon; Park, Eun-Kyung; Kim, Gil-Pyo; Baeck, Sung-Hyeon

2007-11-01

Mesoporous cerium dioxide (Ceria, CeO2) thin films have been successfully electrodeposited onto ITO-coated glass substrates from an aqueous solution of cerium nitrate using CTAB (Cetyltrimethylammonium Bromide) as a templating agent. The synthesized films underwent detailed characterizations. The crystallinity of synthesized CeO2 film was confirmed by XRD analysis and HR-TEM analysis, and surface morphology was investigated by SEM analysis. The presence of mesoporosity in fabricated films was confirmed by TEM and small angle X-ray analysis. As-synthesized film was observed from XRD analysis and HR-TEM image to have well-crystallized structure of cubic phase CeO2. Transmission electron microscopy and small angle X-ray analysis revealed the presence of uniform mesoporosity with a well-ordered lamellar phase in the CeO2 films electrodeposited with CTAB templating.

Room-temperature synthesis and characterization of porous CeO{sub 2} thin films

Energy Technology Data Exchange (ETDEWEB)

Chu, Dewei; Masuda, Yoshitake; Ohji, Tatsuki; Kato, Kazumi [National Institute of Advanced Industrial Science and Technology (AIST), Anagahora, Shimoshidami, Moriyama-ku, Nagoya (Japan)

2012-01-15

CeO{sub 2} thin films with hexagonal-shaped pores were successfully prepared by a facile electrodeposition at room temperature combined with an etching process. By using electrodeposited ZnO nanorods as a soft template, the morphology, and microstructure of the CeO{sub 2} could be controlled. TEM observation indicated that as-prepared CeO{sub 2} film is composed of nanocrystals with average size of several nanometers, while XPS analysis showed the coexistence of Ce{sup 3+} and Ce{sup 4+} in the film. The photoluminescence properties of CeO{sub 2} films were measured, which showed much higher sensitivity compared to bare substrate. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

A Nose for Hydrogen Gas: Fast, Sensitive H2 Sensors Using Electrodeposited Nanomaterials.

Science.gov (United States)

Penner, Reginald M

2017-08-15

showed a faster response to H 2 exposure than Pd nanowires operating at the same elevated temperature, but they had a surprising disadvantage: The resistance change observed for Pt nanowires was exactly the same for all H 2 concentrations. Electron surface scattering was implicated in the mechanism for these sensors. Work on Pt nanowires lead in 2015 to the preparation of Pd nanowires that were electrochemically modified with thin Pt layers (Pd@Pt nanowires). Relative to Pd nanowires, Pt@Pd nanowires showed accelerated response and recovery to H 2 while retaining the same high sensitivity to H 2 concentration seen for sensors based upon pure Pd nanowires. A new chapter in H 2 sensing (2017) involves the replacement of metal nanowires with carbon nanotube ropes decorated with electrodeposited Pd nanoparticles (NPs). Even higher sensitivity and faster sensor response and recovery are enabled by this sensor architecture. Sensor properties are strongly dependent on the size and size monodispersity of the Pd NPs, with smaller NPs yielding higher sensitivity and more rapid response/recovery. We hope the lessons learned from this science over 15 years will catalyze the development of sensors based upon electrodeposited nanomaterials for gases other than H 2 .

Dielectric and electrical conductivity studies of bulk lead (II) oxide (PbO)

Energy Technology Data Exchange (ETDEWEB)

Darwish, A.A.A., E-mail: aaadarwish@gmail.com [Department of Physics, Faculty of Education at Al-Mahweet, Sana’a University, Al-Mahwit (Yemen); Department of Physics, Faculty of Science, University of Tabuk, P.O. Box 741, Tabuk 71491, Tabuk (Saudi Arabia); El-Zaidia, E.F.M.; El-Nahass, M.M. [Department of Physics, Faculty of Education, Ain Shams University, Rorxy, Cairo 11757 (Egypt); Hanafy, T.A. [Department of Physics, Faculty of Science, University of Tabuk, P.O. Box 741, Tabuk 71491, Tabuk (Saudi Arabia); Department of Physics, Faculty of Science, Fayoum University, 63514 El Fayoum (Egypt); Al-Zubaidi, A.A. [Department of Physics, Faculty of Science, University of Tabuk, P.O. Box 741, Tabuk 71491, Tabuk (Saudi Arabia)

2014-03-15

Highlights: • The AC measurements of PbO were measured at temperature range 313–523 K. • The dielectric constants increased with temperature. • The mechanism responsible for AC conduction is electronic hopping. -- Abstract: The dielectric properties, the impedance spectroscopy and AC conductivity of bulk PbO have been investigated as a function of frequency and temperature. The measurements were carried out in the frequency range from 40 to 5 × 10{sup 6} Hz and in temperature range from 313 to 523 K. The frequency response of dielectric constant, ε{sub 1}, and dielectric loss index, ε{sub 2}, as a function of temperature were studied. The values of ε{sub 1} and ε{sub 2} were found to decrease with the increase in frequency. However, they increase with the increase in temperature. The presence of a single arc in the complex modulus spectrum at different temperatures confirms the single-phase character of the PbO. The AC conductivity exhibited a universal dynamic response: σ{sub AC} = Aω{sup s}. The AC conductivity was also found to increase with increasing temperature and frequency. The correlation barrier hopping (CBH) model was found to apply to the AC conductivity data. The calculated values of s were decreased with temperature. This behavior reveals that the conduction mechanism for PbO samples is CBH. The activation energy for AC conductivity decreases with increasing frequency. This confirms that the hopping conduction to the dominant mechanism for PbO samples.

Effect of electrodeposition and annealing of ZnO on optical and photovoltaic properties of the p-Cu2O/n-ZnO solar cells

International Nuclear Information System (INIS)

Hussain, Sajad; Cao Chuanbao; Nabi, Ghulam; Khan, Waheed S.; Usman, Zahid; Mahmood, Tariq

2011-01-01

Highlights: → The p-Cu 2 O/n-ZnO heterojunction was fabricated by using electrodeposition and rf sputtering techniques, respectively. → The effect of electrodeposition on optical and photovoltaic properties of the p-Cu 2 O/n-ZnO solar cells has been examined. → The preannealing of ZnO thin films has enhanced the efficiency of solar cells. → The efficiency of the solar cell was measured 0.46%. - Abstract: Cu 2 O/ZnO p-n heterojunction solar cells were fabricated by rf sputtering deposition of n-ZnO layer, followed by electrodeposition of p-Cu 2 O layer. The different electrodeposition potentials were applied to deposit Cu 2 O on ZnO. The particle size, crystal faces, crystallinity of Cu 2 O is important factor which determine the p-n junction interface and consequently their effect on the performance of the heterojunction solar cell. It is observed that at -0.6 V, p-Cu 2 O film generates fewer surface states in the interband region due to the termination of [1 1 0] resulting in higher efficiency (0.24%) with maximum particle size (53 nm). The bandgap of Cu 2 O at this potential is found to be 2.17 eV. Furthermore, annealing of ZnO film was performed to get rid of deteriorating one and two dimensional defects, which always reduce the performance of solar cell significantly. We found that the solar cell performance efficiency is nearly doubled by increasing the annealing temperature of ZnO thin films due to increasing electrical conductance and electron mobility. Doping studies and fine tuning of the junction morphology will be necessary to further improve the performance of Cu 2 O/ZnO heterojunction solar cells.

PbO networks composed of single crystalline nanosheets synthesized by a facile chemical precipitation method

Energy Technology Data Exchange (ETDEWEB)

Samberg, Joshua P. [Department of Materials Science and Engineering, North Carolina State University, 911 Partners Way, Engineering Building I, Raleigh, NC 27695-7907 (United States); Kajbafvala, Amir, E-mail: amir.kajbafvala@gmail.com [Department of Materials Science and Engineering, North Carolina State University, 911 Partners Way, Engineering Building I, Raleigh, NC 27695-7907 (United States); Koolivand, Amir [Department of Chemistry, North Carolina State University, 2620 Yarbrough Drive, Raleigh, NC 27695 (United States)

2014-03-01

Graphical abstract: - Highlights: • Synthesis of PbO networks through a simple chemical precipitation route. • The synthesis method is rapid and low-cost. • Each network is composed of single crystalline PbO nanosheets. • A possible growth mechanism is proposed for synthesized PbO networks. - Abstract: For the field of energy storage, nanostructured lead oxide (PbO) shows immense potential for increased specific energy and deep discharge for lead acid battery technologies. In this work, PbO networks composed of single crystalline nanosheets were synthesized utilizing a simple, low cost and rapid chemical precipitation method. The PbO networks were prepared in a single reaction vessel from starting reagents of lead acetate dehydrate, ammonium hydroxide and deionized water. Lead acetate dehydrate was chosen as a reagent, as opposed to lead nitrate, to eliminate the possibility of nitrate contamination of the final product. X-ray diffraction (XRD) analysis, high resolution scanning electron microscopy (HRSEM) and high resolution transmission electron microscopy (HRTEM) analysis were used to characterize the synthesized PbO networks. The reproducible method described herein synthesized pure β-PbO (massicot) powders, with no byproducts. A possible formation mechanism for these PbO networks is proposed. The growth is found to proceed predominately in the 〈1 1 1〉 and 〈2 0 0〉 directions while being limited in the 〈0 1 1〉 direction.

PbO networks composed of single crystalline nanosheets synthesized by a facile chemical precipitation method

International Nuclear Information System (INIS)

Samberg, Joshua P.; Kajbafvala, Amir; Koolivand, Amir

2014-01-01

Graphical abstract: - Highlights: • Synthesis of PbO networks through a simple chemical precipitation route. • The synthesis method is rapid and low-cost. • Each network is composed of single crystalline PbO nanosheets. • A possible growth mechanism is proposed for synthesized PbO networks. - Abstract: For the field of energy storage, nanostructured lead oxide (PbO) shows immense potential for increased specific energy and deep discharge for lead acid battery technologies. In this work, PbO networks composed of single crystalline nanosheets were synthesized utilizing a simple, low cost and rapid chemical precipitation method. The PbO networks were prepared in a single reaction vessel from starting reagents of lead acetate dehydrate, ammonium hydroxide and deionized water. Lead acetate dehydrate was chosen as a reagent, as opposed to lead nitrate, to eliminate the possibility of nitrate contamination of the final product. X-ray diffraction (XRD) analysis, high resolution scanning electron microscopy (HRSEM) and high resolution transmission electron microscopy (HRTEM) analysis were used to characterize the synthesized PbO networks. The reproducible method described herein synthesized pure β-PbO (massicot) powders, with no byproducts. A possible formation mechanism for these PbO networks is proposed. The growth is found to proceed predominately in the 〈1 1 1〉 and 〈2 0 0〉 directions while being limited in the 〈0 1 1〉 direction

Composition controlled preparation of Cu–Zn–Sn precursor films for Cu{sub 2}ZnSnS{sub 4} solar cells using pulsed electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Dang, Wenping; Ren, Xiaodong; Zi, Wei; Jia, Lujian [Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Liu, Shengzhong, E-mail: szliu@dicp.ac.cn [Key Laboratory of Applied Surface and Colloid Chemistry, National Ministry of Education, School of Materials Science and Engineering, Shaanxi Normal University, Xi' an 710062 (China); Dalian Institute of Chemical Physics, Dalian National Laboratory for Clean Energy, Chinese Academy of Sciences, Dalian, 116023 (China)

2015-11-25

A pulsed electrodeposition technique is developed to prepare Cu–Zn–Sn (CZT) precursor films for the Cu{sub 2}ZnSnS{sub 4} (CZTS) solar cells. The CZT precursor films are co-deposited on Mo-coated substrate using a cyanide-free electrolyte containing Zn (II) and Sn (II) salts. During the deposition, CuSO{sub 4} solution is supplied at controlled rate using a peristaltic pump to effectively regulate Cu{sup 2+} concentration. In addition, C{sub 6}H{sub 5}Na{sub 3}O{sub 7} is used as a coordination ligand to further balance activities of the Cu{sup 2+}, Sn{sup 2+} and Zn{sup 2+}. The CZTS films are then prepared using a sulfurization process to convert the electrodeposited CZT precursors at 580 °C in a sulphur atmosphere. The annealed thin films are characterized by X-ray diffraction (XRD), Raman spectroscopy, field emission scanning electron microscopy (FE-SEM), EDAX and X-ray photoelectron spectroscopy (XPS) techniques for their structural, morphological, compositional and chemical properties. It is found that the addition rate of Cu (II) has significant effects on the properties of the CZTS thin films. The CZTS film prepared using the optimized copper addition rate (0.15 ml/min) shows pure kesterite phase, Cu-poor and Zn-rich composition, compact morphology and good band gap ∼1.45 eV. Solar cells using the structure glass/Mo/CZTS/CdS/i-ZnO/ZnO:Al achieves a respectable external quantum efficiency and solar cell efficiency. - Highlights: • Developed a composition controlled pulsed electrodeposition for CZTS solar cells. • Electrochemistry and CZT composition regulated by measured Cu supply rate. • Complex chemistry used to regulate ion activities and electrodeposition. • Achieved a respectable CZTS solar cell quantum efficiency.

Electrodeposition: Principles, Applications and Methods

International Nuclear Information System (INIS)

Nur Ubaidah Saidin; Ying, K.K.; Khuan, N.I.

2011-01-01

Electrodeposition technique has been around for a very long time. It is a process of coating a thin layer of one metal on top of a different metal to modify its surface properties, by donating electrons to the ions in a solution. This bottom-up fabrication technique is versatile and can be applied to a wide range of potential applications. Electrodeposition is gaining popularity in recent years due to its capability in fabricating one-dimensional nano structures such as nano rods, nao wires and nano tubes. In this paper, we present an overview on the fabrication and characterization of high aspect ratio nano structures prepared using the nano electrochemical deposition system set up in our laboratory. (author)

Influence of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) on zinc electrodeposition

International Nuclear Information System (INIS)

Lehr, I.L.; Saidman, S.B.

2012-01-01

This work is a study of the electrodeposition of zinc onto SAE 4140 steel electrodes using solutions containing zinc sulfate and bis(2-ethylhexyl) sodium sulfosuccinate (AOT). The influence of different parameters such as electrolyte concentration, electrodeposition time and temperature on the morphology of the electrodeposits was analyzed. The deposits were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction. The variation of open circuit potential over time in chloride solutions was also evaluated. The nucleation-growth process and consequently the morphology of the electrodeposits are modified in the presence of AOT. The surfactant induces the formation of a porous deposit.

Influence of sodium bis(2-ethylhexyl) sulfosuccinate (AOT) on zinc electrodeposition

Science.gov (United States)

Lehr, I. L.; Saidman, S. B.

2012-03-01

This work is a study of the electrodeposition of zinc onto SAE 4140 steel electrodes using solutions containing zinc sulfate and bis(2-ethylhexyl) sodium sulfosuccinate (AOT). The influence of different parameters such as electrolyte concentration, electrodeposition time and temperature on the morphology of the electrodeposits was analyzed. The deposits were characterized by scanning electron microscopy (SEM), energy dispersive X-ray (EDX) and X-ray diffraction. The variation of open circuit potential over time in chloride solutions was also evaluated. The nucleation-growth process and consequently the morphology of the electrodeposits are modified in the presence of AOT. The surfactant induces the formation of a porous deposit.

X-ray spectroscopic study of amorphous and polycrystalline PbO films, α-PbO, and β-PbO for direct conversion imaging.

Science.gov (United States)

Qamar, A; LeBlanc, K; Semeniuk, O; Reznik, A; Lin, J; Pan, Y; Moewes, A

2017-10-13

We investigated the electronic structure of Lead Oxide (PbO) - one of the most promising photoconductor materials for direct conversion x-ray imaging detectors, using soft x-ray emission and absorption spectroscopy. Two structural configurations of thin PbO layers, namely the polycrystalline and the amorphous phase, were studied, and compared to the properties of powdered α-PbO and β-PbO samples. In addition, we performed calculations within the framework of density functional theory and found an excellent agreement between the calculated and the measured absorption and emission spectra, which indicates high accuracy of our structural models. Our work provides strong evidence that the electronic structure of PbO layers, specifically the width of the band gap and the presence of additional interband and intraband states in both conduction and valence band, depend on the deposition conditions. We tested several model structures using DFT simulations to understand what the origin of these states is. The presence of O vacancies is the most plausible explanation for these additional electronic states. Several other plausible models were ruled out including interstitial O, dislocated O and the presence of significant lattice stress in PbO.

Effect of Substrates on the Photoelectrochemical Reduction of Water over Cathodically Electrodeposited p-Type Cu2O Thin Films.

Science.gov (United States)

Shyamal, Sanjib; Hajra, Paramita; Mandal, Harahari; Singh, Jitendra Kumar; Satpati, Ashis Kumar; Pande, Surojit; Bhattacharya, Chinmoy

2015-08-26

In this study, we demonstrate development of p-Cu2O thin films through cathodic electrodeposition technique at constant current of 0.1 mA/cm(2) on Cu, Al, and indium tin oxide (ITO) substrates from basic CuSO4 solution containing Triton X-100 as the surfactant at 30-35 °C. The optical and morphological characterizations of the semiconductors have been carried out using UV-vis spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and Raman spectroscopy. The band gap energy of ∼2.1 eV is recorded, whereas SEM reveals that the surface morphology is covered with Cu2O semiconductors. XRD analyses confirm that with change in substrate, the size of Cu2O "cubic" crystallites decreases from ITO to Al to Cu substrates. Photoelectrochemical characterizations under dark and illuminated conditions have been carried out through linear sweep voltammetry, chronoamperometry and electrochemical impedance spectroscopic analysis. The photoelectrochemical reduction of water (H2O → H2) in pH 4.9 aqueous solutions over the different substrates vary in the order of Cu > Al > ITO. The highest current of 4.6 mA/cm(2) has been recorded over the Cu substrate even at a low illumination of 35 mW/cm(2), which is significantly higher than the values (2.4 mA/cm(2) on Au coated FTO or 4.07 mA/cm(2) on Cu foil substrate at an illumination of 100 mW/cm(2)) reported in literature.

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.

Lead Oxide- PbO Humidity Sensor

Directory of Open Access Journals (Sweden)

Sk. Khadeer Pasha

2010-11-01

Full Text Available Alcohol thermal route has been used to synthesize nanocrystalline PbO at a low temperature of 75 oC using lead acetate. The synthesized PbO (P75 was annealed in the temperatures ranging from 200-500 oC for 2 h to study the effect of crystal structure and phase changes and were labeled as P200, P300, P400 and P500, respectively. X-Ray diffraction and FT-IR spectroscopy were carried out to identify the structural phases and vibrational stretching frequencies respectively. The TEM images revealed the porous nature of P75 sample which is an important criterion for the humidity sensor. The dc resistance measurements were carried out in the relative humidity (RH range 5-98 %. Among the different prepared, P75 possessed the highest humidity sensitivity of 6250, while the heat treated sample P500 have a low sensitivity of 330. The response and recovery characteristics of the maximum sensitivity sample P75 were 170 s and 40 s respectively.

Electrochemical preparation and characterization of CuInSe{sub 2} thin films for photovoltaic applications; Preparacion electroquimica y caracterizacion de laminas delgadas de CuInSe{sub 2} para aplicaciones fotovoltaicas

Energy Technology Data Exchange (ETDEWEB)

Guillen Arqueros, C

1993-12-31

The objective of this work has been to investigate the electrodeposition as a low-cost, large-area fabrication process to obtain CuInSe{sub 2} this films for efficient photovoltaic devices. this objective entails the elucidation of thin film deposition mechanism, the study of the fundamental properties of electrodeposited material, and also the modification of their physical and chemical parameters for photovoltaic applications. CuInSe{sub 2} thin films have been successfully electrodeposited from a citric was characterized by compositional, structural, electrical, optical and electrochemical measurements, relating their properties with the preparation parameters and also studying the effect of various thermal and chemical treatments. The results showed post-deposition treatment are needed for optimizing these films for solar cells fabrication: first, an annealing in inert atmosphere at temperatures above 400 degrees celsius to obtain a high recrystallization in the chalcopyrite structure, and after a chemical etching in KCN solution to remove secondary phases of Cu{sub x}Se and Se which are frequently electrodeposited with the CuInSe{sub 2}. The treated samples showed appropriate photovoltaic activity in a semiconductor-electrolite liquid junction. (author) 193 ref.

Enhancement of solar hydrogen evolution from water by surface modification with CdS and TiO2 on porous CuInS2 photocathodes prepared by an electrodeposition-sulfurization method.

Science.gov (United States)

Zhao, Jiao; Minegishi, Tsutomu; Zhang, Li; Zhong, Miao; Gunawan; Nakabayashi, Mamiko; Ma, Guijun; Hisatomi, Takashi; Katayama, Masao; Ikeda, Shigeru; Shibata, Naoya; Yamada, Taro; Domen, Kazunari

2014-10-27

Porous films of p-type CuInS2, prepared by sulfurization of electrodeposited metals, are surface-modified with thin layers of CdS and TiO2. This specific porous electrode evolved H2 from photoelectrochemical water reduction under simulated sunlight. Modification with thin n-type CdS and TiO2 layers significantly increased the cathodic photocurrent and onset potential through the formation of a p-n junction on the surface. The modified photocathodes showed a relatively high efficiency and stable H2 production under the present reaction conditions. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

ELECTRODEPOSITION OF NICKEL ON URANIUM

Science.gov (United States)

Gray, A.G.

1958-08-26

A method is described for preparing uranium objects prior to nickel electroplating. The process consiats in treating the surface of the uranium with molten ferric chloride hexahydrate, at a slightiy elevated temperature. This treatment etches the metal surface providing a structure suitable for the application of adherent electrodeposits and at the same time plates the surface with a thin protective film of iron.

Effects of PbO on the oxide films of incoloy 800HT in simulated primary circuit of PWR

International Nuclear Information System (INIS)

Tan, Yu; Yang, Junhan; Wang, Wanwan; Shi, Rongxue; Liang, Kexin; Zhang, Shenghan

2016-01-01

Effects of trace PbO on oxide films of Incoloy 800HT were investigated in simulated primary circuit water chemistry of PWR, also with proper Co addition. The trace PbO addition in high temperature water blocked the protective spinel oxides formation of the oxide films of Incoloy 800HT. XPS results indicated that the lead, added as PbO into the high temperature water, shows not only +2 valance but also +4 and 0 valances in the oxide film of 800HT co-operated with Fe, Cr and Ni to form oxides films. Potentiodynamic polarization results indicated that as PbO concentration increased, the current densities of the less protective oxide films of Incoloy 800HT decreased in a buffer solution tested at room temperature. The capacitance results indicated that the donor densities of oxidation film of Incoloy 800HT decreased as trace PbO addition into the high temperature water. - Highlights: • Trace PbO addition into the high temperature water block the formation of spinel oxides on Incoloy 800HT. • The donor density of oxide film decreases with trace PbO addition. • The current density of potentiodynamic polarization decreases of oxide film with trace PbO addition.

Growth and characterization of ZnO thin films prepared by electrodeposition technique

Energy Technology Data Exchange (ETDEWEB)

Fahoume, M.; Maghfoul, O.; Aggour, M. [L.P.M.C., Faculte des Sciences, Universite Ibn Tofail, BP. 133-14000 Kenitra (Morocco); Hartiti, B. [L.P.M.A.E.R., Faculte des Sciences et Techniques, B.P. 146 Mohammedia (Morocco); Chraibi, F.; Ennaoui, A. [L.P.M., Faculte des Sciences, Universite Mohammed V, BP.1014 Rabat (Morocco)

2006-06-15

ZnO thin films were deposited on either indium tin oxide-coated glass or copper substrate by the electrodeposition process, using zinc chloride and flowing air as precursors. The effect of pH on the structural and morphological ZnO films was studied and the optimum deposition conditions have been outlined. The kinetics of the growth of the films have been investigated. We note that the rate of deposition of ZnO in an acidic solution was larger than in a basic solution. The structure of the films was studied using X-ray diffractometry (XRD) and transmission electron microscopy (TEM). The surface morphology and thickness of the films were determined using scanning electron microscopy. The X-ray diffraction analysis shows that the films are polycrystalline with hexagonal crystal structure (zincite) at pH 4. The optical transmittance of ZnO decreases with varying film thickness. The optical energy bandgap was found to be 3.26eV. (author)

Effect of electrodeposition potential on composition and morphology ...

Indian Academy of Sciences (India)

The underpotential deposition mechanism of Cu–Se and In–Se phases was observed in ... Thin films; cyclic voltammetry; CuInGaSe (CIGS); solar cell; electrodeposition. 1. ... trode was a Pt spiral wire and the working electrode was. 735 ...

Stability of B2O3-PbO glasses under irradiation

International Nuclear Information System (INIS)

Biron, I.; Barbu, A.

1987-07-01

The stability of B 2 O 3 -PbO glasses under in situ electron irradiation have been investigated owing to a careful measurement of the local temperature rise of the sample under the beam. It is shown that, both inside and outside miscibility gap, droplets of pure lead feature Brownian Motion and coagulate at a rate depending on the electron flux and the temperature. The evolution of the density of particle have been measured and by using the coagulation theory of Smoluchowsky, the viscosity of the practically pur B 2 O 3 matrix has been obtained: it is drastically reduced by up to 10 orders of magnitude by irradiation. It is shown and discussed that this effect come from electronic excitation but is much more important when atomic displacement are present

Influence of titanium oxide films on copper nucleation during electrodeposition

International Nuclear Information System (INIS)

Chang, Hyun K.; Choe, Byung-Hak; Lee, Jong K.

2005-01-01

Copper electrodeposition has an important industrial role because of various interconnects used in electronic devices such as printed wire boards. With an increasing trend in device miniaturization, in demand are void-free, thin copper foils of 10 μm thick or less with a very low surface profile. In accordance, nucleation kinetics of copper was studied with titanium cathodes that were covered with thin, passive oxide films of 2-3 nm. Such an insulating oxide layer with a band gap of 3 eV is supposed to nearly block charge transfer from the cathode to the electrolyte. However, significant nucleation rates of copper were observed. Pipe tunneling mechanism along a dislocation core is reasoned to account for the high nucleation kinetics. A dislocation core is proposed to be a high electron tunneling path with a reduced energy barrier and a reduced barrier thickness. In supporting the pipe tunneling mechanism, both 'in situ' and 'ex situ' scratch tests were performed to introduce extra dislocations into the cathode surface, that is, more high charge paths via tunneling, before electrodeposition

Moessbauer study in the glass system PbO. 2B/sub 2/O/sub 3/. Fe/sub 2/O/sub 3/

Energy Technology Data Exchange (ETDEWEB)

Sekhon, S S; Kamal, R [Punjabi Univ., Patiala (India). Dept. of Physics

1978-05-01

The Moessbauer technique has been employed to study the structure and crystallite formation in the glass system PbO.2B/sub 2/O/sub 3/ containing upto 30 wt% Fe/sub 2/O/sub 3/. Like alkali borate glasses, this glass system also exhibits a broadened quadrupole doublet and iron ions are present in Fe/sup 3 +/ state. Above about 20 wt%, the crystallites of magnetically ordered states have been identified. Susceptibility variation with concentration suggests the formation of a superparamagnetic state.

The poisoning effect of PbO on Mn-Ce/TiO{sub 2} catalyst for selective catalytic reduction of NO with NH{sub 3} at low temperature

Energy Technology Data Exchange (ETDEWEB)

Zhou, Lingling [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Li, Caiting, E-mail: ctli@hnu.edu.cn [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China); Zhao, Lingkui; Zeng, Guangming; Gao, Lei; Wang, Yan; Yu, Ming’e [College of Environmental Science and Engineering, Hunan University, Changsha 410082 (China); Key Laboratory of Environmental Biology and Pollution Control (Hunan University), Ministry of Education, Changsha 410082 (China)

2016-12-15

Highlights: • The poisoning effects of PbO-doped Mn-Ce/TiO{sub 2} catalysts for low temperature NH{sub 3}-SCR were investigated. • Low concentration of Mn{sup 4+} and chemisorbed oxygen (O{sub b}) were not favorable for the generation of intermediates. • The decreased Ce{sup 3+} and less reducible of manganese oxides hindered the redox cycle (Mn{sup 3+} + Ce{sup 4+} ↔ Mn{sup 4+} + Ce{sup 3+}). • The doping of PbO not only altered acid sites but also inhibited ammonia adsorption as well as activation. • The poisoning of PbO resulted in the decrease of ad-NO{sub x} species (only a spot of bidentate nitrates remained). - Abstract: Lead oxide (PbO) as one of the typical heavy metals in flue gas from power plants has strong accumulation as well as poisoning effects on SCR catalysts. In this paper, a series of PbO-doped Mn-Ce/TiO{sub 2} catalysts were synthesized by impregnation method. The poisoning effects of PbO over Mn-Ce/TiO{sub 2} samples for selective catalytic reduction of NO by NH{sub 3} were investigated based on catalytic activity test and characterizations. The NO conversion of Mn-Ce/TiO{sub 2} was greatly decreased after the addition of PbO. It was obvious that the NO conversion efficiency of Mn-Ce/TiO{sub 2} catalyst declined from 96.75% to about 40% at 200 °C when Pb:Mn molar ratio reached 0.5. Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), Hydrogen temperature programmed reduction (H{sub 2}-TPR), Ammonia temperature programmed desorption (NH{sub 3}-TPD) and Fourier transform infrared spectroscopy (FT-IR) were carried out to study the deactivation reasons of PbO poisoned catalysts. Manganese oxides’ crystallization, less reducible of manganese and cerium oxides, the decreasing of surface area, Mn{sup 4+} as well as Ce{sup 3+} concentration and chemisorbed oxygen (O{sub b}) after the introduction of PbO, all of these resulted in a poor SCR performance

Electrodeposition of organic-inorganic tri-halide perovskites solar cell

Science.gov (United States)

Charles, U. A.; Ibrahim, M. A.; Teridi, M. A. M.

2018-02-01

Perovskite (CH3NH3PbI3) semiconductor materials are promising high-performance light energy absorber for solar cell application. However, the power conversion efficiency of perovskite solar cell is severely affected by the surface quality of the deposited thin film. Spin coating is a low-cost and widely used deposition technique for perovskite solar cell. Notably, film deposited by spin coating evolves surface hydroxide and defeats from uncontrolled precipitation and inter-diffusion reaction. Alternatively, vapor deposition (VD) method produces uniform thin film but requires precise control of complex thermodynamic parameters which makes the technique unsuitable for large scale production. Most deposition techniques for perovskite require tedious surface optimization to improve the surface quality of deposits. Optimization of perovskite surface is necessary to significantly improve device structure and electrical output. In this review, electrodeposition of perovskite solar cell is demonstrated as a scalable and reproducible technique to fabricate uniform and smooth thin film surface that circumvents the need for high vacuum environment. Electrodeposition is achieved at low temperatures, supports precise control and optimization of deposits for efficient charge transfer.

Influence of secondary phases during annealing on re-crystallization of CuInSe{sub 2} electrodeposited films

Energy Technology Data Exchange (ETDEWEB)

Gobeaut, A. [Laboratoire de Reactivite et Chimie des Solides, 33 rue St Leu, 80039 Amiens (France); Laffont, L., E-mail: lydia.laffont@u-picardie.f [Laboratoire de Reactivite et Chimie des Solides, 33 rue St Leu, 80039 Amiens (France); Tarascon, J.-M. [Laboratoire de Reactivite et Chimie des Solides, 33 rue St Leu, 80039 Amiens (France); Parissi, L.; Kerrec, O. [Institut de Recherche et de Developpement de l' Energie Photovoltaique, 6 quai Watier, 78401 Chatou cedex (France)

2009-06-01

Electrodeposited CuInSe{sub 2} thin films are of potential importance, as light absorber material, in the next generation of photovoltaic cells as long as we can optimize their annealing process to obtain dense and highly crystalline films. The intent of this study was to gain a basic understanding of the key experimental parameters governing the structural-textural-composition evolution of thin films as function of the annealing temperature via X-ray diffraction, scanning/transmission electron microscopy and thermal analysis measurements. The crystallization of the electrodeposited CuInSe{sub 2} films, with the presence of Se and orthorhombic Cu{sub 2} {sub -} {sub x}Se (o-Cu{sub 2} {sub -} {sub x}Se) phases, occurs over two distinct temperature ranges, between 220 {sup o}C and 250 {sup o}C and beyond 520 {sup o}C. Such domains of temperature are consistent with the melting of elemental Se and the binary CuSe phase, respectively. The CuSe phase forming during annealing results from the reaction between the two secondary species o-Cu{sub 2} {sub -} {sub x}Se and Se (o-Cu{sub 2} {sub -} {sub x}Se + Se {yields} 2 CuSe) but can be decomposed into the cubic {beta}-Cu{sub 2} {sub -} {sub x}Se phase by slowing down the heating rate. Formation of liquid CuSe beyond 520{sup o}C seems to govern both the grain size of the films and the porosity of the substrate-CuInSe{sub 2} film interface. A simple model explaining the competitive interplay between the film crystallinity and the interface porosity is proposed, aiming at an improved protocol based on temperature range, which will enable to enhance the film crystalline nature while limiting the interface porosity.

Effects of air dielectric barrier discharge plasma treatment time on surface properties of PBO fiber

International Nuclear Information System (INIS)

Wang Qian; Chen Ping; Jia Caixia; Chen, Mingxin; Li Bin

2011-01-01

In this paper, the effects of air dielectric barrier discharge (DBD) plasma treatment time on surface properties of poly(p-phenylene benzobisoxazole) (PBO) fiber were investigated. The surface characteristics of PBO fiber before and after the plasma treatments were analyzed by dynamic contact angle (DCA) analysis, scanning electron microscopy (SEM), atomic force microscopy (AFM) and X-ray photoelectron spectroscopy (XPS). DCA measurements indicated that the surface wettability of PBO fiber was improved significantly by increasing the fiber surface free energy via air DBD plasma treatments. The results were confirmed by the improvement of adhesion of a kind of thermoplastic resin to PBO fiber which was observed by SEM, showing that more resin was adhering evenly to the fiber surface. AFM measurement revealed that the surface topography of PBO fiber became more complicated and the surface roughness was greatly enhanced after the plasma treatments, and XPS analysis showed that some new polar groups (e.g. -O-C=O) were introduced on plasma treated PBO fiber surface. The results of this study also showed that the surface properties of PBO fiber changed with the elongation of plasma treatment time.

CZTS absorber layer for thin film solar cells from electrodeposited metallic stacked precursors (Zn/Cu-Sn)

Energy Technology Data Exchange (ETDEWEB)

Khalil, M.I., E-mail: mdibrahim.khalil@polimi.it [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano (Italy); Atici, O. [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano (Italy); Lucotti, A. [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Piazza Leonardo da Vinci 32, 20133 Milano (Italy); Binetti, S.; Le Donne, A. [Department of Materials Science and Solar Energy Research Centre (MIB-SOLAR), University of Milano- Bicocca, Via Cozzi 53, 20125 Milano (Italy); Magagnin, L., E-mail: luca.magagnin@polimi.it [Dipartimento di Chimica, Materiali e Ing. Chimica “Giulio Natta”, Politecnico di Milano, Via Mancinelli 7, 20131 Milano (Italy)

2016-08-30

Highlights: • CZTS absorber layer was fabricated by electrodeposition—annealing route from stacked bilayer precursor (Zn/Cu-Sn). • Different characterization techniques have ensured the well formed Kesterite CZTS along the film thickness also. • Two different excitation wavelengths of laser lines (514.5 and 785 nm) have been used for the Raman characterization of the films. • No significant Sn loss is observed in CZTS films after the sulfurization of the stacked bilayer precursors. • Photoluminescence spectroscopy reveals the PL peak of CZTS at 1.15 eV at low temperature (15 K). - Abstract: In the present work, Kesterite-Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films were successfully synthesized from stacked bilayer precursor (Zn/Cu-Sn) through electrodeposition-annealing route. Adherent and homogeneous Cu-poor, Zn-rich stacked metal Cu-Zn-Sn precursors with different compositions were sequentially electrodeposited, in the order of Zn/Cu-Sn onto Mo foil substrates. Subsequently, stacked layers were soft annealed at 350 °C for 20 min in flowing N{sub 2} atmosphere in order to improve intermixing of the elements. Then, sulfurization was completed at 585 °C for 15 min in elemental sulfur environment in a quartz tube furnace with N{sub 2} atmosphere. Morphological, compositional and structural properties of the films were investigated using SEM, EDS and XRD methods. Raman spectroscopy with two different excitation lines (514.5 and 785 nm), has been carried out on the sulfurized films in order to fully characterize the CZTS phase. Higher excitation wavelength showed more secondary phases, but with low intensities. Glow discharge optical emission spectroscopy (GDOES) has also been performed on films showing well formed Kesterite CZTS along the film thickness as compositions of the elements do not change along the thickness. In order to investigate the electronic structure of the CZTS, Photoluminescence (PL) spectroscopy has been carried out on the films, whose

Humidity-sensitive characteristics of PbCrO4-PbO thick film elements. PbCrO4-PbO kei atsumaku soshi no kanshitsu tokusei

Energy Technology Data Exchange (ETDEWEB)

Kaneko, F [Shonan Institute of Technology, Kanagawa (Japan); Nanba, N [Kantogakuin University, Tokyo (Japan)

1992-12-20

This paper describes humidity-sensitive characteristics, which depend on the host composition being PbCrO4 or Pb2CrO5, in the system PbCrO4 combined with various oxides, such as Al2O3, Fe2O3, ZrO2, SnO2, TiO2, ThO2, and Ta2O5. In order to confirm the predominant phase over elements in the system PbCrO4-PbO, the effect of composition and microstructure on the humidity-sensitive characteristics of thick film elements were examined. Consequently, it was found that the humidity-sensitivity in low humidity region increased as the host composition of elements changed from hydrophobic PbCrO4 to hydrophilic Pb2CrO5. It was also shown that these results can be interpreted by a humidity-sensitive mechanism proposed for hydrophilic Pb2CrO5. Furthermore, an absorption model of H2O molecules on to the surface of Pb2CrO5 in the PbCrO4-PbO system humidity sensor was provided. 4 refs., 12 figs.

Electrodeposition of ZnO nano-wires lattices with a controlled morphology

International Nuclear Information System (INIS)

Elias, J.; Tena-Zaera, R.; Katty, A.; Levy-Clement, C.

2006-01-01

In this work, it is shown that the electrodeposition is a changeable low cost method which allows, according to the synthesis conditions, to obtain not only plane thin layers of ZnO but different nano-structures too. In a first part, are presented the formation conditions of a compact thin layer of nanocrystalline ZnO electrodeposited on a conducing glass substrate. This layer plays a buffer layer role for the deposition of a lattice of ZnO nano-wires. The step of nano-wires nucleation is not only determined by the electrochemical parameters but by the properties of the buffer layer too as the grain sizes and its thickness. In this context, the use of an electrodeposition method in two steps allows to control the nano-wires length and diameter and their density. The morphology and the structural and optical properties of these nano-structures have been analyzed by different techniques as the scanning and transmission electron microscopy, the X-ray diffraction and the optical spectroscopy. These studies show that ZnO nano-structures are formed of monocrystalline ZnO nano-wires, presenting a great developed surface and a great optical transparency in the visible. These properties make ZnO a good material for the development of nano-structured photovoltaic cells as the extremely thin absorber cells (PV ETA) or those with dye (DSSC) which are generally prepared with porous polycrystalline TiO 2 . Its replacement by a lattice of monocrystalline ZnO nano-wires allows to reduce considerably the number of grain boundaries and in consequence to improve the transport of the electrons. The results are then promising for the PV ETA cells with ZnO nano-wires. (O.M.)

Texture control and seeded nucleation of nanosize structures of ferroelectric thin films

Science.gov (United States)

Muralt, Paul

2006-09-01

An overview is given on nucleation phenomena of Pb(Zr ,Ti)O3 (PZT) thin films on Pt(111)-based substrates. Emphasis is given on in situ growth methods, particularly in situ reactive sputtering from three metallic targets. Growth of PZT thin films is discussed from the point of view of the PbOx-TiO2 phase diagram, PbO vapor pressure, and classical nucleation theory. The role of thin TiO2 affinity layers and spots is explained in the frame of this theory. Activation energies for desorption and chemisorption are adapted to comply with the fact that nucleation rates on TiO2 are much larger than the ones on bare Pt(111). The model reproduces well the PbO surface flux from bare Pt(111) to the affinity spots in the case of PbTiO3 nucleation and the reversed tendency in the case of PZT 40/60 nucleation, explaining experimental observations. The critical size of nuclei was calculated to contain 8-10unit cells for PbTiO3/Pt nucleation and 14-17 for PZT/Pt nucleation.

Effect of PbO on the elastic behavior of ZnO–P2O5 glass systems

Directory of Open Access Journals (Sweden)

H.A.A. Sidek

Full Text Available A series of ternary phosphate glasses in the form of 40(P2O5–(60 − xZnO–xPbO and 50(P2O5–(50 − xZnO–xPbO where x = 0–60 mol%, have been successfully prepared by conventional melt quenching technique. Both longitudinal and shear ultrasonic velocities were measured in different compositions of PbO using the MBS8000 ultrasonic data acquisition system at 10 MHz frequency and at room temperature. The ultrasonic velocity data, the density and the calculated elastic moduli are found to be composition dependent and discussed in terms of PbO modifiers. The correlation of elastic moduli with the atomic packing density of these glasses was discussed. To predict the compositional dependence of elastic moduli of this glass system, the interpretation of the variation in the experimental elastic behavior observed has been studied based on various of the bond compression and the Makishima–Mackenzie models. Keywords: Elastic moduli, Glasses, Zinc phosphate, Bond compression, Makishima–Mackenzie models

Tuning the electrodeposition parameters of silver to yield micro/nano structures from room temperature protic ionic liquids

International Nuclear Information System (INIS)

Suryanto, Bryan H.R.; Gunawan, Christian A.; Lu Xunyu; Zhao Chuan

2012-01-01

Controlled electrodeposition of silver onto glassy carbon, gold and indium tin oxide-coated glass substrates has been achieved from three room temperature protic ionic liquids (PILs), ethylammonium nitrate, triethylammonium methylsulfonate, and bis(2-methoxyethyl)ammonium acetate. Cyclic voltammetric, chronoamperometric, together with microscopic and X-ray techniques reveal that micro/nanostructured Ag thin films of controlled morphology, size, density, and uniformity can be achieved by tuning the electrodeposition parameters such as potential, time, types of PILs, substrate materials, and ionic liquid viscosity by altering the water content. Chronoamperometric results provide direct evidence that electrodeposition of Ag in protic ionic liquids takes place through a progressive nucleation and diffusion-controlled 3D growth mechanism. The as prepared Ag micro/nanoparticles have been employed as electrocatalysts for oxygen reduction reaction and exhibit excellent catalytic activity. The study provides promise for using protic ionic liquids as alternative electrolytes to conventional aprotic ionic liquids for electrodeposition of metals and nanostructured electrocatalysts.

Preparation of CuGaSe2 absorber layers for thin film solar cells by annealing of efficiently electrodeposited Cu-Ga precursor layers from ionic liquids

International Nuclear Information System (INIS)

Steichen, M.; Larsen, J.; Guetay, L.; Siebentritt, S.; Dale, P.J.

2011-01-01

CuGaSe 2 absorber layers were prepared on molybdenum substrates by electrochemical codeposition of copper and gallium and subsequential annealing in selenium vapour. The electrodeposition was made from a deep eutectic based ionic liquid consisting of choline chloride/urea (Reline) with a plating efficiency of over 85%. The precursor film composition is controlled by the ratio of the copper to gallium fluxes under hydrodynamic conditions and by the applied deposition potential. X-ray diffraction reveals CuGa 2 alloying during the electrodeposition and CuGaSe 2 formation after annealing. Photoluminescence (PL) and photocurrent spectroscopy revealed the good opto-electronic properties of the CuGaSe 2 absorber films. The absorber layers have been converted to full devices with the best device achieving 4.0 % solar conversion efficiency.

Thin metal organic frameworks coatings by cathodic electrodeposition for solid-phase microextraction and analysis of trace exogenous estrogens in milk.

Science.gov (United States)

Lan, Hangzhen; Pan, Daodong; Sun, Yangying; Guo, Yuxing; Wu, Zhen

2016-09-21

Cathodic electrodeposition (CED) has received great attention in metal-organic frameworks (MOFs) synthesis due to its distinguished properties including simplicity, controllability, mild synthesis conditions, and product continuously. Here, we report the fabrication of thin (Et3NH)2Zn3(BDC)4 (E-MOF-5) film coated solid phase microextraction (SPME) fiber by a one-step in situ cathodic electrodeposition strategy. Several etched stainless steel fibers were placed in parallel in order to achieve simultaneously electrochemical polymerization. The influence of different polymerization parameters Et3NHCl concentration and polymerization time were evaluated. The proposed method requires only 20 min for the preparation of E-MOF-5 coating. The optimum coating showed excellent thermal stability and mechanical durability with a long lifetime of more than 120 repetitions SPME operations, and also exhibited higher extraction selectivity and capacity to four estrogens than commonly-used commercial PDMS coating. The limits of detection for the estrogens were 0.17-0.56 ng mL(-1). Fiber-to-fiber reproducibility (n = 8) was in the respective ranges of 3.5%-6.1% relative standard deviation (RSD) for four estrogens for triplicate measurements at 200 ng mL(-1). Finally, the (E-MOF-5) coated fiber was evaluated for ethinylestradiol (EE2), bisphenol A (BPA), diethylstilbestrol (DES), and hexestrol (HEX) extraction in the spiked milk samples. The extraction performance of this new coating was satisfied enough for repeatable use without obvious decline. Copyright © 2016 Elsevier B.V. All rights reserved.

PBO Borehole Strainmeters and Pore Pressure Sensors: Recording Hydrological Strain Signals

Science.gov (United States)

Gottlieb, M. H.; Hodgkinson, K. M.; Mencin, D.; Henderson, D. B.; Johnson, W.; Van Boskirk, E.; Pyatt, C.; Mattioli, G. S.

2017-12-01

UNAVCO operates a network of 75 borehole strainmeters along the west coast of the United States and Vancouver Island, Canada as part of the Plate Boundary Observatory (PBO), the geodetic component of the NSF-funded Earthscope program. Borehole strainmeters are designed to detect variations in the strain field at the nanostrain level and can easily detect transient strains caused by aseismic creep events, Episodic Tremor and Slip (ETS) events and seismically induced co- and post-seimic signals. In 2016, one strainmeter was installed in an Oklahoma oil field to characterize in-situ deformation during CO2 injection. Twenty-three strainmeter sites also have pore pressure sensors to measure fluctuations in groundwater pressure. Both the strainmeter network and the pore pressure sensors provide unique data against which those using water-level measurements, GPS time-series or InSAR data can compare possible subsidence signals caused by groundwater withdrawal or fluid re-injection. Operating for 12 years, the PBO strainmeter and pore pressure network provides a long-term, continuous, 1-sps record of deformation. PBO deploys GTSM21 tensor strainmeters from GTSM Technologies, which consist of four horizontal strain gauges stacked vertically, at different orientations, within a single 2 m-long instrument. The strainmeters are typically installed at depths of 200 to 250 m and grouted into the bottom of 15 cm diameter boreholes. The pore pressure sensors are Digiquartz Depth Sensors from Paros Scientific. These sensors are installed in 2" PVC, sampling groundwater through a screened section 15 m above the co-located strainmeter. These sensors are also recording at 1-sps with a resolution in the hundredths of hPa. High-rate local barometric pressure data and low-rate rainfall data also available at all locations. PBO Strainmeter and pore pressure data are available in SEED, SAC-ASCII and time-stamped ASCII format from the IRIS Data Managements Center. Strainmeter data are

Variation of magnetoimpedance of electrodeposited NiFe/Cu with deposition current density

Science.gov (United States)

Mishra, A. C.; Jha, A. K.

2017-12-01

An investigation about influence of deposition current density on electrodeposited magnetic film is reported in this paper. Ferromagnetic NiFe thin films were electrodeposited on copper wires of 100 μm diameter for various electrdepostion current densities ranging from 10 to 60 mA/cm2 maintaining equal thickness in all films. The composition of deposited film varied with deposition current density and in particular, a composition of Ni79Fe21 was achieved for a current density of 20 mA/cm2. The surface microstructure of the film deposited at the current density of 20 mA/cm2 was found to have excellent smoothness. The coercivity of the film was lowest and highest value of magnetoimpedance was measured for this film. The influence of current density on film composition and hence magnetic properties was attributed to the change of deposition mechanism.

Electrodeposited cadmium selenide films for solar cells; Electrodeposition de couches minces de CdSe: Application a la conversion photovoltaique

Energy Technology Data Exchange (ETDEWEB)

Bnamar, E.; Rami, M.; Fahoume, M.; Chraibi, F.; Ennaoui, A. [Universite Mohammed 5, Rabat (Morocco). Faculte des Sciences; Fahoume, M. [Universite Ibn Tofail, Faculte des Sciences, Kenitra (Morocco)

1998-01-01

Solar cells based on II-IV semiconductors are among the leading candidates for low-cost photovoltaic conversion of solar energy due to their high absorption coefficients and therefore the low materials consumption for their production. The synthesis of polycrystalline Cd Se thin films by cathodic electrodeposition on conducting substrates is described in this paper. Electrodeposition involves potentiostatic reduction from an acid aqueous bath. The influence of bath temperature and deposition potential on the crystallinity is discussed. For optimized deposition parameters, the XRD patterns reveal cubic and hexagonal Cd Se. Electron probe microanalysis shows an excess of Se in the samples. Photoelectrochemical studies of the films in aqueous polysulfide allowed us to determine the photovoltaic properties e.g.: semiconducting type, short-circuit current, open circuit voltage and fill factor. (authors) 5 refs.

Effects of highly ordered TiO2 nanotube substrates on the nucleation of Cu electrodeposits.

Science.gov (United States)

Ryu, Won Hee; Park, Chan Jin; Kwon, Hyuk Sang

2010-05-01

We investigated the effects of TiO2 nanotube substrates on the nucleation density of Cu during electrodeposition in a solution of CuSO4 and H2SO4 at 50 degrees C compared with those of pure Ti and micro-porous TiO2 substrates. During electrodeposition, the density of Cu nuclei on the TiO2 nanotube substrate increased and the average size of Cu nuclei decreased with increasing anodizing voltage and time for the synthesis of the substrate. In addition, the nucleation density of Cu electrodeposits on the highly ordered TiO2 nanotube substrate was much higher than that on pure Ti and micro-porous TiO2 substrates.

PBO Operations in Alaska and Cascadia, Combining Regions and Collaborating with our Regional Partners

Science.gov (United States)

Austin, K. E.; Boyce, E. S.; Dausz, K.; Feaux, K.; Mattioli, G. S.; Pyatt, C.; Willoughby, H.; Woolace, A. C.

2015-12-01

During the last year, the Alaska and the Cascadia regions of the EarthScope Plate Boundary Observatory (PBO) network were combined into a single management unit. While both remain distinct regions with their own challenges and engineering staff, every effort has been made to operate as a single team to improve efficiency and provide the highest possible data quality and uptime. Over the last several years a concerted effort has been made to work collaboratively with other institutions and stakeholders to defray ongoing costs by sharing staff and resources. UNAVCO currently operates four integrated GPS/seismic stations in collaboration with the Alaska Earthquake Center, eight with the Alaska Volcano Observatory, and three with the EarthScope TA. By the end of 2015, PBO and TA plan to install another 3 integrated and/or co-located geodetic and seismic systems. While most of these are designed around existing PBO stations, the 2014 installation at Middleton Island is a new station for both groups, providing PBO with an opportunity to expand geodetic data in Alaska. There were two major joint maintenance efforts in 2015:, the largest was a 5 day mission among PBO, AVO, and TA, which shared boat, helicopter, and staff on and around Augustine Volcano; the second, was a 10 day helicopter mission shared between AVO and PBO on Unimak Island. PBO Pacific Northwest is working closely with University of Washington to co-locate at least 9 Earthquake Early Warning Systems, which include the addition of strong motion sensors and high speed RT telemetry at PBO sites. The project is managed by University of Washington but UNAVCO is providing land contact information and infrastructure support. Summer 2015 upgrades include a complete overhaul of aging radio technology at two major networks and several small radio networks in Cascadia. The upgrades will increase reliability and enhance the speed of existing telemetry infrastructure and will continue through summer 2018.

Electrochemical Deposition of Lanthanum Telluride Thin Films and Nanowires

Science.gov (United States)

Chi, Su (Ike); Farias, Stephen; Cammarata, Robert

2013-03-01

Tellurium alloys are characterized by their high performance thermoelectric properties and recent research has shown nanostructured tellurium alloys display even greater performance than bulk equivalents. Increased thermoelectric efficiency of nanostructured materials have led to significant interests in developing thin film and nanowire structures. Here, we report on the first successful electrodeposition of lanthanum telluride thin films and nanowires. The electrodeposition of lanthanum telluride thin films is performed in ionic liquids at room temperature. The synthesis of nanowires involves electrodepositing lanthanum telluride arrays into anodic aluminum oxide (AAO) nanoporous membranes. These novel procedures can serve as an alternative means of simple, inexpensive and laboratory-environment friendly methods to synthesize nanostructured thermoelectric materials. The thermoelectric properties of thin films and nanowires will be presented to compare to current state-of-the-art thermoelectric materials. The morphologies and chemical compositions of the deposited films and nanowires are characterized using SEM and EDAX analysis.

Effect of deposition temperature of TiO2 on the piezoelectric property of PbTiO3 film grown by PbO gas phase reaction sputtering

International Nuclear Information System (INIS)

Kim, Jiyoon; Kim, Yunseok; Park, Moonkyu; No, Kwangsoo; Hong, Seungbum; Buehlmann, Simon; Kim, Yong Kwan

2010-01-01

A 17 nm thick PbTiO 3 (PTO) films were fabricated via PbO gas phase reaction with TiO 2 starting layer in a sputtering chamber. The influence of deposition temperature of TiO 2 on the piezoelectric properties of PTO thin films was investigated. The remnant piezoresponse of PTO films nonlinearly increased as a function of TiO 2 deposition temperature, which is correlated with the increase in average grain diameter of PTO film. As grain size increases, the restriction on remnant piezoresponse imposed by the grain boundary via coupling between local strain and polarization becomes less pronounced, which results in the increase in remnant piezoresponse. Furthermore, we found that the vertical shift in piezoresponse hysteresis loops is closely related to the residual stress state. A strong correlation between the negative vertical shift and the residual tensile stress reveals that residual stress on the resulting PTO film contributed to the asymmetric piezoelectric property.

Electro-Plating and Characterisation of CdTe Thin Films Using CdCl2 as the Cadmium Source

Directory of Open Access Journals (Sweden)

Nor A. Abdul-Manaf

2015-09-01

Full Text Available Cadmium telluride (CdTe thin films have been successfully prepared from an aqueous electrolyte bath containing cadmium chloride (CdCl2·H2O and tellurium dioxide (TeO2 using an electrodeposition technique. The structural, electrical, morphological and optical properties of these thin films have been characterised using X-ray diffraction (XRD, Raman spectroscopy, optical profilometry, DC current-voltage (I-V measurements, photoelectrochemical (PEC cell measurement, scanning electron microscopy (SEM, atomic force microscopy (AFM and UV-Vis spectrophotometry. It is observed that the best cathodic potential is 698 mV with respect to standard calomel electrode (SCE in a three electrode system. Structural analysis using XRD shows polycrystalline crystal structure in the as-deposited CdTe thin films and the peaks intensity increase after CdCl2 treatment. PEC cell measurements show the possibility of growing p-, i- and n-type CdTe layers by varying the growth potential during electrodeposition. The electrical resistivity of the as-deposited layers are in the order of 104 Ω·cm. SEM and AFM show that the CdCl2 treated samples are more roughness and have larger grain size when compared to CdTe grown by CdSO4 precursor. Results obtained from the optical absorption reveal that the bandgap of as-deposited CdTe (1.48–1.52 eV reduce to (1.45–1.49 eV after CdCl2 treatment. Full characterisation of this material is providing new information on crucial CdCl2 treatment of CdTe thin films due to its built-in CdCl2 treatment during the material growth. The work is progressing to fabricate solar cells with this material and compare with CdTe thin films grown by conventional sulphate precursors.

Electrodeposition of Fe{sub 2}O{sub 3} nanoparticles and its supercapacitive properties

Energy Technology Data Exchange (ETDEWEB)

Kadam, S. L., E-mail: snehal.kadam54@gmail.com; Padwal, P. M., E-mail: pal-soni279@yahoo.com; Mane, S. M., E-mail: manesagar99@gmail.com; Kulkarni, S. B., E-mail: sbk-physics@yahoo.com [Department of Physics, The Institute of Science, Madam Cama Road, Mumbai-400032 (India)

2016-04-13

Fe{sub 2}O{sub 3} metal oxide nanoparticles are synthesized by electrodeposition method on stainless steel substrate. The crystal structure and surface morphological studies of the obtained metal oxide thin film are carried out by using X-ray diffraction (XRD) technique and Scanning Electron Microscopy (SEM) respectively. The electrochemical properties of Fe{sub 2}O{sub 3} thin film like Cyclic Voltammetry (CV), Galvonostatic Charge-Discharge (GCD) and Electrochemical Impedance Spectroscopy (EIS) are studied in a bath of 0.5 M Na{sub 2}SO{sub 4} as electrolyte. The observed specific capacitance shows improved values 135 Fg{sup −1} at 5 mVs{sup −1} scan rate. The electrochemical stability of Fe{sub 2}O{sub 3} electrode is investigated using cyclic voltammetry for 1000 cycles at a scan rate 50 mVs{sup −1}. The Fe{sub 2}O{sub 3} electrode exhibits superior cycling stability with only 4-5% capacitance loss after one thousand cycles. The values of specific power and specific energy of Fe{sub 2}O{sub 3} electrode obtained from Galvonostatic charge discharge studies are 2250 W.kg{sup −1} and 63.15 Wh.kg{sup −1} respectively at current density 1 A/g. From all the electrochemical properties of Fe{sub 2}O{sub 3} electrode, it indicates that it will be promising electrode material for supercapacitor application.

Preparation and properties of antimony thin film anode materials

Institute of Scientific and Technical Information of China (English)

SU Shufa; CAO Gaoshao; ZHAO Xinbing

2004-01-01

Metallic antimony thin films were deposited by magnetron sputtering and electrodeposition. Electrochemical properties of the thin film as anode materials for lithium-ion batteries were investigated and compared with those of antimony powder. It was found that both magnetron sputtering and electrodeposition are easily controllable processes to deposit antimony films with fiat charge/discharge potential plateaus. The electrochemical performances of antimony thin films, especially those prepared with magnetron sputtering, are better than those of antimony powder. The reversible capacities of the magnetron sputtered antimony thin film are above 400 mA h g-1 in the first 15 cycles.

Characterizations of electrodeposited Ni–CeO{sub 2} nanocomposite coatings

Energy Technology Data Exchange (ETDEWEB)

Kasturibai, S., E-mail: s.kasturibai@yahoo.co.in [Department of Chemistry, Alagappa Government Arts College, Karaikudi 630 003, Tamilnadu (India); Advanced Nanocomposite Coatings Laboratory, Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamilnadu (India); Kalaignan, G. Paruthimal, E-mail: pkalaignan@yahoo.com [Advanced Nanocomposite Coatings Laboratory, Department of Industrial Chemistry, School of Chemical Sciences, Alagappa University, Karaikudi 630 003, Tamilnadu (India)

2014-10-15

The expansion of current machinery requires metallic materials with better surface properties. In the present investigation, CeO{sub 2} reinforced nickel nanocomposite coatings were deposited on mild steel substrate by direct current electrodeposition process employing nickel acetate bath. The effect of incorporation of CeO{sub 2} particles in the Ni nanocomposite coatings on the micro hardness and corrosion behaviour has been evaluated. Smooth and compact nanocomposite deposits containing well-distributed cerium oxide particles were obtained. The crystallite structure was fcc for electrodeposited nickel and Ni–CeO{sub 2} nanocomposite coatings. It has been observed that, the presence of CeO{sub 2} nanoparticles favours the [111] and [200] texture of nickel matrix. The co-deposition of CeO{sub 2} nanoparticles with nickel was found to be favoured at applied current density of 8 A dm{sup −2}. The micro hardness values of the nickel nanocomposite coatings (725 HV) was higher than that of pure nickel (265 HV).The decrease in I{sub corr} values and increase in Constant Phase Element values were investigated in 3.5% NaCl solution which showed the higher corrosion resistant nature of Ni–CeO{sub 2} coatings. - Highlights: • Ni–CeO{sub 2} composite coatings have electrodeposited from eco-friendly acetate bath. • Inclusion of CeO{sub 2} in the composite coating has refined the crystallite size. • Micro hardness values have increased with CeO{sub 2} content in the composite coatings. • The negative shift of E{sub corr} confirming cathodic protective nature of coatings.

Investigation of electronic quality of electrodeposited cadmium sulphide layers from thiourea precursor for use in large area electronics

Energy Technology Data Exchange (ETDEWEB)

Ojo, A.A., E-mail: chartell2006@yahoo.com; Dharmadasa, I.M.

2016-09-01

CdS layers used in thin film solar cells and other electronic devices are usually grown by wet chemical methods using CdCl{sub 2} as the Cadmium source and either Na{sub 2}S{sub 2}O{sub 3}, NH{sub 4}S{sub 2}O{sub 3} or NH{sub 2}CSNH{sub 2} as Sulphur sources. Obviously, one of the sulphur precursors should produce more suitable CdS layers required to give the highest performing devices. This can only be achieved by comprehensive experimental work on growth and characterisation of CdS layers from the above mentioned sulphur sources. This paper presents the results observed on CdS layers grown by electrodepositing using two electrode configuration and thiourea as the sulphur precursor. X-ray diffraction (XRD), Raman spectroscopy, optical absorption, scanning electron microscopy (SEM), energy-dispersive X-ray analysis (EDX) and photoelectrochemical (PEC) cell methods have been used to characterise the material properties. In order to test and study the electronic device quality of the layers, ohmic and rectifying contacts were fabricated on the electroplated layers. Schottky barriers, formed on the layers were also compared with previously reported work on Chemical Bath Deposited CBD-CdS layers and bulk single crystals of CdS. Comparatively, Schottky diodes fabricated on electroplated CdS layers using two-electrode system and thiourea precursor exhibit excellent electronic properties suitable for electronic devices such as thin film solar panels and large area display devices. - Highlights: • Precipitate-free electrodeposition of CdS is achievable using Thiourea precursor. • Electrodeposition of CdS using 2-electrode configuration. • The electrodeposited CdS shows excellent electronic properties. • Exploration of the effect of heat treatment temperature and heat treatment duration.

Study of SrBi4Ti4O15 (SBTi) dielectric properties of doped PbO

International Nuclear Information System (INIS)

Rodrigues Junior, C.A.; Silva Filho, J.M.; Freitas, D.B.; Oliveira, R.G.M.; Sombra, B.; Sales, J.C.

2012-01-01

The ceramic SrBi 4 Ti 4 O 15 (SBTI), cation-deficient perovskite A 5 B 4 O 15 , was prepared by the method of solid state reaction and then doped with PbO (in the range 2-10% by weight). The samples were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and impedance spectroscopy at room temperature. The X-ray analysis was performed by the Rietveld refinement. The micrographs of the samples show globular-shaped grains (doped PbO). The dielectric properties: dielectric constant (Κ' or έ) and dielectric loss tangent (tan δ), were measured at room temperature in the frequency range 100 Hz - 1 MHz dielectric properties of these 1 MHz sample doped with 10 % PbO showed the dielectric constant Κ'= 168.34 and dielectric loss tangent tanδ, = 7,1.10 -2 . These results show a good possibility of miniaturization of electronic devices such as capacitors. (author)

The effect of solution pH on the electrochemical performance of nanocrystalline metal ferrites MFe2O4 (M=Cu, Zn, and Ni) thin films

Science.gov (United States)

Elsayed, E. M.; Rashad, M. M.; Khalil, H. F. Y.; Ibrahim, I. A.; Hussein, M. R.; El-Sabbah, M. M. B.

2016-04-01

Nanocrystalline metal ferrite MFe2O4 (M=Cu, Zn, and Ni) thin films have been synthesized via electrodeposition-anodization process. Electrodeposited (M)Fe2 alloys were obtained from aqueous sulfate bath. The formed alloys were electrochemically oxidized (anodized) in aqueous (1 M KOH) solution, at room temperature, to the corresponding hydroxides. The parameters controlling the current efficiency of the electrodeposition of (M)Fe2 alloys such as the bath composition and the current density were studied and optimized. The anodized (M)Fe2 alloy films were annealed in air at 400 °C for 2 h. The results revealed the formation of three ferrite thin films were formed. The crystallite sizes of the produced films were in the range between 45 and 60 nm. The microstructure of the formed film was ferrite type dependent. The corrosion behavior of ferrite thin films in different pH solutions was investigated using open circuit potential (OCP) and potentiodynamic polarization measurements. The open circuit potential indicates that the initial potential E im of ZnFe2O4 thin films remained constant for a short time, then sharply increased in the less negative direction in acidic and alkaline medium compared with Ni and Cu ferrite films. The values of the corrosion current density I corr were higher for the ZnFe2O4 films at pH values of 1 and 12 compared with that of NiFe2O4 and CuFe2O4 which were higher only at pH value 1. The corrosion rate was very low for the three ferrite films when immersion in the neutral medium. The surface morphology recommended that Ni and Cu ferrite films were safely used in neutral and alkaline medium, whereas Zn ferrite film was only used in neutral atmospheres.

Thermodynamics of gallium arsenide electrodeposition

International Nuclear Information System (INIS)

Perrault, G.G.

1986-01-01

Gallium Arsenide is well known as a very interesting compound for photoelectrical devices. Up to now, it has been prepared mostly by high temperature technology, and the authors considered that it might be of interest to set up an electrodeposition technique suitable to prepare thin layers of this compound. A reaction sequence similar to the one observed for Cadmium Sulfide or Cadmium Telluride could be considered. In these cases, the metal chalcogenide is obtained from the precipitation of the metal ions dissolved in the solutions by the reduction product of the metalloidic compound

ANOMALOUS ELECTRODEPOSITION OF Fe-Ni ALLOY COATING FROM SIMPLE AND COMPLEX BATHS AND ITS MAGNETIC PROPERTY

Directory of Open Access Journals (Sweden)

M A Islam

2010-03-01

Full Text Available Electrodeposition of Fe-Ni thin films has been carried on copper substrate under various electrodeposition conditions from two simple and six complex baths. Sulfate baths composing of NiSO4. 7H2O, FeSO4.7H2O, H3BO3 and Na2SO4KEYWORDS: Anomalous Electrodeposition, Fe-Ni Coating, Complexing agent, Current Density, Magnetic Property. 1. INTRODUCTION Alloy electrodeposition technologies can extend tremendously the potential of electrochemical deposition processes to provide coatings that require unique mechanical, chemical and physical properties [1]. There has been a great research interest in the development and characterization of iron-nickel (Fe-Ni thin films due to their operational capacity, economic interest, magnetic and other properties [2]. Due to their unique low coefficient of thermal expansion (CTE and soft magnetic properties, Fe-Ni alloys have been used in industrial applications for over 100 years [3]. Typical examples of applications that are based on the low CTE of Fe-Ni alloys include: thermostatic bimetals, glass sealing, integrated circuit packaging, cathode ray tube, shadow masks, membranes for liquid natural gas tankers; applications based on the soft magnetic properties include: read-write heads for magnetic storage, magnetic actuators, magnetic shielding, high performance transformer cores. comprise the simple baths whereas complex baths were prepared by adding ascorbic acid, saccharin and citric acid in simple baths. The effect of bath composition, pH and applied current density on coating appearance, composition, morphology and magnetic property were studied. Wet chemical analysis technique was used to analyze the coating composition whereas SEM and VSM were used to study the deposit morphology and magnetic property respectively. Addition of complexing agents in plating baths suppressed the anomalous nature of Fe-Ni alloy electrodeposition. Coatings obtained from simple baths were characterized by coarse grained non

Photon mass attenuation coefficients of a silicon resin loaded with WO3, PbO, and Bi2O3 Micro and Nano-particles for radiation shielding

Science.gov (United States)

Verdipoor, Khatibeh; Alemi, Abdolali; Mesbahi, Asghar

2018-06-01

Novel shielding materials for photons based on silicon resin and WO3, PbO, and Bi2O3 Micro and Nano-particles were designed and their mass attenuation coefficients were calculated using Monte Carlo (MC) method. Using lattice cards in MCNPX code, micro and nanoparticles with sizes of 100 nm and 1 μm was designed inside a silicon resin matrix. Narrow beam geometry was simulated to calculate the attenuation coefficients of samples against mono-energetic beams of Co60 (1.17 and 1.33 MeV), Cs137 (663.8 KeV), and Ba133 (355.9 KeV). The shielding samples made of nanoparticles had higher mass attenuation coefficients, up to 17% relative to those made of microparticles. The superiority of nano-shields relative to micro-shields was dependent on the filler concentration and the energy of photons. PbO, and Bi2O3 nanoparticles showed higher attenuation compared to WO3 nanoparticles in studied energies. Fabrication of novel shielding materials using PbO, and Bi2O3 nanoparticles is recommended for application in radiation protection against photon beams.

Magnetic properties and microstructure investigation of electrodeposited FeNi/ITO films with different thickness

International Nuclear Information System (INIS)

Cao, Derang; Wang, Zhenkun; Feng, Erxi; Wei, Jinwu; Wang, Jianbo; Liu, Qingfang

2013-01-01

Highlights: •FeNi alloy thin films with different thickness deposited on Indium Tin Oxides (ITOs) conductive glass substrates by electrodeposition method. •A columnar crystalline microstructure and domain structure were obtained in FeNi thin films. •Particular FMR spectra of FeNi alloy with different thickness were studied. -- Abstract: FeNi alloy thin films with different thickness deposited on Indium Tin Oxides (ITOs) conductive glass substrates from the electrolytes by electrodeposition method have been studied by magnetic force microscopy (MFM), scanning electron microscopy (SEM) and ferromagnetic resonance (FMR) technique. For these films possessing an in-plane isotropy, the remanence decreases with the increasing of film thickness and the critical thickness that a stripe domain structure emerges is about 116 nm. Characteristic differences of the FMR spectra of different thickness are also observed. The results show that the resonance field at high measured angle increases firstly then decreases with increasing thickness, which may be related to the striped domain structure

Electrochemical synthesis of nanoplatelets-like CuS0.2Se0.8 thin film for photoluminescence applications

Directory of Open Access Journals (Sweden)

Sharma A. K.

2015-06-01

Full Text Available Copper sulfide-selenide (CuS0.2Se0.8 thin films were deposited on FTO coated glass substrate (fluorine doped tin oxide and stainless steel substrates using electrodeposition technique. Deposited thin films were characterized using different characterization techniques viz. X-ray diffraction (XRD, scanning electron microscopy (SEM, UV-Vis spectroscopy, photoluminescence spectroscopy and surface wettability. XRD study showed polycrystalline nature with cubic phase of the films. Scanning electron microscopy showed that the surface area of the substrate was covered by the nanoplatelets structure of a thickness of 140 to 150 nm and optical study showed that the direct band gap was ~1.90 eV. Surface wettability showed hydrophobic nature of the CuS0.2Se0.8 thin films.

Uranium enrichment reduction in the Prototype Gen-IV sodium-cooled fast reactor (PGSFR) with PBO reflector

Energy Technology Data Exchange (ETDEWEB)

Hartanto, Donny; Kim, Chi Hyung; Kim, Yong Hee [Dept. of Nuclear and Quantum Engineering, Korea Advanced Institute of Science and Technology (KAIST), Daejeon (Korea, Republic of)

2016-04-15

The Korean Prototype Gen-IV sodium-cooled fast reactor (PGSFR) is supposed to be loaded with a relatively-costly low-enriched U fuel, while its envisaged transuranic fuels are not available for transmutation. In this work, the U-enrichment reduction by improving the neutron economy is pursued to save the fuel cost. To improve the neutron economy of the core, a new reflector material, PbO, has been introduced to replace the conventional HT9 reflector in the current PGSFR core. Two types of PbO reflectors are considered: one is the conventional pin-type and the other one is an inverted configuration. The inverted PbO reflector design is intended to maximize the PbO volume fraction in the reflector assembly. In addition, the core radial configuration is also modified to maximize the performance of the PbO reflector. For the baseline PGSFR core with several reflector options, the U enrichment requirement has been analyzed and the fuel depletion analysis is performed to derive the equilibrium cycle parameters. The linear reactivity model is used to determine the equilibrium cycle performances of the core. Impacts of the new PbO reflectors are characterized in terms of the cycle length, neutron leakage, radial power distribution, and operational fuel cost.

ELECTRO-DEGRADATION OF REACTIVE BLUE DYES USING CYLINDER MODIFIED ELECTRODE: Ti/β-PbO2 AS DIMENSIONALLY STABLE ANODE

Directory of Open Access Journals (Sweden)

Aris Mukimin

2010-12-01

Full Text Available A cylinder modified electrode of the β-PbO2 was fabricated by anodic electro-deposition method on titanium substrate. The PbO2 layer prepared from high acid solution (pH: 0.3 that contains a mixed of 0.5 M Pb(NO32, 1 M HNO3, and 0,02 M NaF. The physicochemical properties of the PbO2 electrode were analyzed by using Energy Dispersive X-Ray Analysis and X-Ray Diffraction. The analyses have shown that oxide layer has an O/Pb ratio about 1.6 and the PbO impurities are formed in the surface layer besides the β-PbO2. The modified electrode was used as anode paired stainless cathode in the electro-degradation of reactive blue dye. The results of the electro-catalytic oxidation process of the dye solution were expressed in terms of the remaining intensity dye and chemical oxygen demand (COD values. The modified electrode has removal efficiency of the reactive blue dye at voltage of 7 V, pH of 7, concentration NaCl of 2 g/L, initial dye concentration of 100 mg/L with simple and short time operations.

Micro-electrodeposition techniques for the preparation of small actinide counting sources for ultra-high resolution alpha spectrometry by microcalorimetry

International Nuclear Information System (INIS)

Plionis, A.A.; Hastings, E.P.; LaMont, S.P.; Dry, D.E.; Bacrania, M.K.; Rabin, M.W.; Rim, J.H.

2009-01-01

Special considerations and techniques are desired for the preparation of small actinide counting sources. Counting sources have been prepared on metal disk substrates (planchets) with an active area of only 0.079 mm 2 . This represents a 93.75% reduction in deposition area from standard electrodeposition methods. The actinide distribution upon the smaller planchet must remain thin and uniform to allow alpha particle emissions to escape the counting source with a minimal amount of self-attenuation. This work describes the development of micro-electrodeposition methods and optimization of the technique with respect to deposition time and current density for various planchet sizes. (author)

Cathodic electrodeposition of amorphous elemental selenium from an air- and water-stable ionic liquid.

Science.gov (United States)

Redman, Daniel W; Murugesan, Sankaran; Stevenson, Keith J

2014-01-14

Electrodeposition of selenium from 1-propyl-1-methylpiperidinium bis(trifluoromethylsulfonyl)imide is reported. In situ UV-vis spectroelectrochemistry was used to investigate the reduction of diethyl selenite to form elemental selenium thin films from an ionic liquid-acetonitrile medium. Three reduction peaks of diethyl selenite were observed via cyclic voltammetry and are attributed to the stepwise reduction of the selenium precursor adsorbed on the electrode. The electrodeposition mechanism is influenced by both potential and time. Electrodeposition at -1.7 V vs Pt QRE resulted in the deposition of elemental selenium nanoparticles that with time coalesced to form a continuous film. At reduction potentials more negative than -1.7 V the morphology of the deposit changed significantly due to the reduction of elemental Se to Se(2-). In addition, p-type photoconductivity of the films was observed during the spectroelectrochemical measurements. X-ray diffraction and Raman spectroscopy confirmed that the deposited selenium films were amorphous. X-ray photoelectron spectroscopy and energy dispersive X-ray spectroscopy confirm the films consisted of pure selenium with minor residual contamination from the precursor and ionic liquid.

Electrodeposition synthesis and electrochemical properties of nanostructured γ-MnO 2 films

Science.gov (United States)

Chou, Shulei; Cheng, Fangyi; Chen, Jun

The thin films of carambola-like γ-MnO 2 nanoflakes with about 20 nm in thickness and at least 200 nm in width were prepared on nickel sheets by combination of potentiostatic and cyclic voltammetric electrodeposition techniques. The as-prepared MnO 2 nanomaterials, which were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), were used as the active material of the positive electrode for primary alkaline Zn/MnO 2 batteries and electrochemical supercapacitors. Electrochemical measurements showed that the MnO 2 nanoflake films displayed high potential plateau (around 1.0 V versus Zn) in primary Zn/MnO 2 batteries at the discharge current density of 500 mA g -1 and high specific capacitance of 240 F g -1 at the current density of 1 mA cm -2. This indicated the potential application of carambola-like γ-MnO 2 nanoflakes in high-power batteries and electrochemical supercapacitors. The growth process for the one- and three-dimensional nanostructured MnO 2 was discussed on the basis of potentiostatic and cyclic voltammetric techniques. The present synthesis method can be extended to the preparation of other nanostructured metal-oxide films.

Diffusion and segregation of substrate copper in electrodeposited Ni-Fe thin films

International Nuclear Information System (INIS)

Ahadian, M.M.; Iraji zad, A.; Nouri, E.; Ranjbar, M.; Dolati, A.

2007-01-01

The Cu surface segregation is investigated in the electrodeposited Ni-Fe layers using X-ray photoelectron spectroscopy (XPS), Auger electron spectroscopy (AES), secondary ion mass spectroscopy (SIMS) and atomic force microscopy (AFM). The results indicate that Cu segregation and accumulation take place in areated and deareated baths and the amount of segregated copper increases after air exposure. This phenomenon is explained by lower interfacial tension of the Cu in comparison with Ni and Fe. Our results reveal more surface segregation in the electrodeposit than vacuum reported results. This should be due to interface charging and higher surface diffusion in applied potential. The effect of interface charging on the interfacial tension is discussed based on Lippmann equation. Increasing of the Cu accumulation after air exposure is related to selective oxidation in alloys and higher tendency of Cu to surface oxidation

Recent Advances in Superhydrophobic Electrodeposits

Directory of Open Access Journals (Sweden)

Jason Tam

2016-03-01

Full Text Available In this review, we present an extensive summary of research on superhydrophobic electrodeposits reported in the literature over the past decade. As a synthesis technique, electrodeposition is a simple and scalable process to produce non-wetting metal surfaces. There are three main categories of superhydrophobic surfaces made by electrodeposition: (i electrodeposits that are inherently non-wetting due to hierarchical roughness generated from the process; (ii electrodeposits with plated surface roughness that are further modified with low surface energy material; (iii composite electrodeposits with co-deposited inert and hydrophobic particles. A recently developed strategy to improve the durability during the application of superhydrophobic electrodeposits by controlling the microstructure of the metal matrix and the co-deposition of hydrophobic ceramic particles will also be addressed.

The effect of annealing on structural, optical and photosensitive properties of electrodeposited cadmium selenide thin films

Directory of Open Access Journals (Sweden)

Somnath Mahato

2017-06-01

Full Text Available Cadmium selenide (CdSe thin films have been deposited on indium tin oxide coated glass substrate by simple electrodeposition method. X-ray Diffraction (XRD studies identify that the as-deposited CdSe films are highly oriented to [002] direction and they belong to nanocrystalline hexagonal phase. The films are changed to polycrystalline structure after annealing in air for temperatures up to 450 °C and begin to degrade afterwards with the occurrence of oxidation and porosity. CdSe completely ceases to exist at higher annealing temperatures. CdSe films exhibit a maximum absorbance in the violet to blue-green region of an optical spectrum. The absorbance increases while the band gap decreases with increasing annealing temperature. Surface morphology also shows that the increase of the annealing temperature caused the grain growth. In addition, a number of distinct crystals is formed on top of the film surface. Electrical characteristics show that the films are photosensitive with a maximum sensitivity at 350 °C.

Improvement of interfacial adhesion and nondestructive damage evaluation for plasma-treated PBO and Kevlar fibers/epoxy composites using micromechanical techniques and surface wettability.

Science.gov (United States)

Park, Joung-Man; Kim, Dae-Sik; Kim, Sung-Ryong

2003-08-15

Comparison of interfacial properties and microfailure mechanisms of oxygen-plasma treated poly(p-phenylene-2,6-benzobisoxazole (PBO, Zylon) and poly(p-phenylene terephthalamide) (PPTA, Kevlar) fibers/epoxy composites were investigated using a micromechanical technique and nondestructive acoustic emission (AE). The interfacial shear strength (IFSS) and work of adhesion, Wa, of PBO or Kevlar fiber/epoxy composites increased with oxygen-plasma treatment, due to induced hydrogen and covalent bondings at their interface. Plasma-treated Kevlar fiber showed the maximum critical surface tension and polar term, whereas the untreated PBO fiber showed the minimum values. The work of adhesion and the polar term were proportional to the IFSS directly for both PBO and Kevlar fibers. The microfibril fracture pattern of two plasma-treated fibers appeared obviously. Unlike in slow cooling, in rapid cooling, case kink band and kicking in PBO fiber appeared, whereas buckling in the Kevlar fiber was observed mainly due to compressive and residual stresses. Based on the propagation of microfibril failure toward the core region, the number of AE events for plasma-treated PBO and Kevlar fibers increased significantly compared to the untreated case. The results of nondestructive AE were consistent with microfailure modes.

Experimental Study of Liquidus of the "FeO"-SiO2-PbO Slags in Equilibrium with Air and with Metallic Lead

Science.gov (United States)

Shevchenko, Maksym; Hidayat, Taufiq; Hayes, Peter C.; Jak, Evgueni

Limited data are available on phase equilibria of the "FeO"-SiO2-PbO slag system at conditions used in the lead smelting due to difficulties from lead vaporization and interactions with metal and ceramic crucibles. Recently experimental procedures have been developed and successfully applied to complex industrial slag-metal-matte systems involving high temperature equilibration on a primary phase substrate and rapid quenching followed by the electron probe X-ray microanalysis. The liquidus isotherms and invariant lines in the "FeO"-SiO2-PbO slag system in equilibrium with air and with metallic lead have been constructed. Preliminary data compared to the FactSage package predictions demonstrate differences in some aspects, indicating the possibility for further improvement of the thermodynamic database. The present work is a part of the integrated experimental and thermodynamic modelling research program on multi-phase lead systems in support of the optimization and development of complex lead smelting, refining and recycling technologies.

Nanoindentation and micro-mechanical fracture toughness of electrodeposited nanocrystalline Ni–W alloy films

International Nuclear Information System (INIS)

Armstrong, D.E.J.; Haseeb, A.S.M.A.; Roberts, S.G.; Wilkinson, A.J.; Bade, K.

2012-01-01

Nanocrystalline nickel–tungsten alloys have great potential in the fabrication of components for microelectromechanical systems. Here the fracture toughness of Ni–12.7 at.%W alloy micro-cantilever beams was investigated. Micro-cantilevers were fabricated by UV lithography and electrodeposition and notched by focused ion beam machining. Load was applied using a nanoindenter and fracture toughness was calculated from the fracture load. Fracture toughness of the Ni–12.7 at.%W was in the range of 1.49–5.14 MPa √m. This is higher than the fracture toughness of Si (another important microelectromechanical systems material), but considerably lower than that of electrodeposited nickel and other nickel based alloys. - Highlights: ► Micro-scale cantilevers manufactured by electro-deposition and focused ion beam machining. ► Nanoindenter used to perform micro-scale fracture test on Ni-13at%W micro-cantilevers. ► Calculation of fracture toughness of electrodeposited Ni-13at%W thin films. ► Fracture toughness values lower than that of nanocrystalline nickel.

Nanoindentation and micro-mechanical fracture toughness of electrodeposited nanocrystalline Ni-W alloy films

Energy Technology Data Exchange (ETDEWEB)

Armstrong, D.E.J., E-mail: david.armstrong@materials.ox.ac.uk [Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH (United Kingdom); Haseeb, A.S.M.A. [Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Roberts, S.G.; Wilkinson, A.J. [Department of Materials, University of Oxford, Parks Road, Oxford, OX1 3PH (United Kingdom); Bade, K. [Institut fuer Mikrostrukturtechnik (IMT), Karlsruhe Institute of Technology, Hermann-von-Helmholtz-Platz 1, 76344 Eggenstein-Leopoldshafen (Germany)

2012-04-30

Nanocrystalline nickel-tungsten alloys have great potential in the fabrication of components for microelectromechanical systems. Here the fracture toughness of Ni-12.7 at.%W alloy micro-cantilever beams was investigated. Micro-cantilevers were fabricated by UV lithography and electrodeposition and notched by focused ion beam machining. Load was applied using a nanoindenter and fracture toughness was calculated from the fracture load. Fracture toughness of the Ni-12.7 at.%W was in the range of 1.49-5.14 MPa {radical}m. This is higher than the fracture toughness of Si (another important microelectromechanical systems material), but considerably lower than that of electrodeposited nickel and other nickel based alloys. - Highlights: Black-Right-Pointing-Pointer Micro-scale cantilevers manufactured by electro-deposition and focused ion beam machining. Black-Right-Pointing-Pointer Nanoindenter used to perform micro-scale fracture test on Ni-13at%W micro-cantilevers. Black-Right-Pointing-Pointer Calculation of fracture toughness of electrodeposited Ni-13at%W thin films. Black-Right-Pointing-Pointer Fracture toughness values lower than that of nanocrystalline nickel.

Effect of parameters on the electrodeposition of Ni-TiO2 nanocomposite coatings

International Nuclear Information System (INIS)

Le Thi Phuong Thao; Nguyen Duc Hung; Nguyen Duy Ket

2013-01-01

The Ni-TiO 2 composite was formed from nickel chloride solution by coelectrodeposition. Effect of stirring rate, current density, kind of current, electrodeposition time and concentration of TiO 2 in the solution on the codeposition of the particle in the nanocomposite coating was investigated. The composition of coating was characterized with energy dispersive analyzer system (EDX). Results showed that, the amount of nano-TiO 2 embedded in coatings depended on these factors. When the amount of nanoparticles in bath of electrochemical was 6 g/1, the codeposition of the TiO 2 particle in the matrix reached 10.53% at current density 3 A/dm 2 , stirring rate of 600 rpm and 20 minutes electrodeposition. (author)

Electrodeposition Techniques for the Preparation of Beta-Sprectroscopy Sources of Rare-Earth Elements

DEFF Research Database (Denmark)

Hansen, P. Gregers; Høgh, J.; Nielsen, H. L.

1964-01-01

Thin, uniform radioactive deposits of rare earths and related elements can be prepared by cathodic electrodeposition of their hydroxides. The main theoretical and experimental features of this process are reviewed and plating cell design and the choice of conditions are described together...

Ballistic magnetoresistance of electrodeposited nanocontacts in thin film and micrometer wire gaps

International Nuclear Information System (INIS)

Garcia, N.; Cheng, H.; Wang, H.; Nikolic, N.D.; Guerrero, C.A.; Papageorgopoulos, A.C.

2004-01-01

In this paper, we review the recent advances and progress in ballistic magnetoresistance (BMR) in magnetic nanocontacts electrodeposited in thin films and micrometer gaps. We report the influence of magnetostriction in the measurements under different configurations and substrates, as well as the contribution of the magnetic material forming the contacts. To avoid the magnetostriction effect, we have fabricated magnetic nanocontacts in Cu wires and Cu films. Similar BMR results can be observed in these systems. Our results show that the BMR effect should depend on the microproperties of the nanocontacts and should not be related with the macroproperties of the electrodes. The magnetostriction results, measured by an atomic force microscopy system with a built-in electromagnet, clearly show that there is no direct relationship between the displacement (caused by the magnetostriction effect) and the value of BMR. In fact, we present large magnetoresistance values for permalloy, coinciding with displacements in the latter's structure less than 1 nm, which is the smallest clearly observable shift allowed by our atomic force microscope. Repetitions of hundreds of R(H) curves are presented for different materials with different coercive fields. The interpretation of the results is based on the formation of an interfacial transparent layer (non-stoichiometric oxide, sulfur, etc.) at the nanocontact where the theory can explain large magnetoresistance values

Electro-Deposition Laboratory

Data.gov (United States)

Federal Laboratory Consortium — The electro-deposition laboratory can electro-deposit various coatings onto small test samples and bench level prototypes. This facility provides the foundation for...

Atomistic minimal model for estimating profile of electrodeposited nanopatterns

Science.gov (United States)

Asgharpour Hassankiadeh, Somayeh; Sadeghi, Ali

2018-06-01

We develop a computationally efficient and methodologically simple approach to realize molecular dynamics simulations of electrodeposition. Our minimal model takes into account the nontrivial electric field due a sharp electrode tip to perform simulations of the controllable coating of a thin layer on a surface with an atomic precision. On the atomic scale a highly site-selective electrodeposition of ions and charged particles by means of the sharp tip of a scanning probe microscope is possible. A better understanding of the microscopic process, obtained mainly from atomistic simulations, helps us to enhance the quality of this nanopatterning technique and to make it applicable in fabrication of nanowires and nanocontacts. In the limit of screened inter-particle interactions, it is feasible to run very fast simulations of the electrodeposition process within the framework of the proposed model and thus to investigate how the shape of the overlayer depends on the tip-sample geometry and dielectric properties, electrolyte viscosity, etc. Our calculation results reveal that the sharpness of the profile of a nano-scale deposited overlayer is dictated by the normal-to-sample surface component of the electric field underneath the tip.

Microscopic and magnetic properties of template assisted electrodeposited iron nanowires

Energy Technology Data Exchange (ETDEWEB)

Irshad, M. I., E-mail: imrancssp@gmail.com; Mohamed, N. M., E-mail: noranimuti-mohamed@petronas.com.my; Yar, A., E-mail: asfandyarhargan@gmail.com [Department of Fundamental & Applied Sciences, Universiti Teknologi PETRONAS, 31750 PERAK (Malaysia); Ahmad, F., E-mail: faizahmad@petronas.com.my; Abdullah, M. Z., E-mail: zaki-abdullah@petronas.com.my [Department of Mechanical Engineering, Universiti Teknologi PETRONAS, 31750 PERAK (Malaysia)

2015-07-22

Nanowires of magnetic materials such as Iron, nickel, cobalt, and alloys of them are one of the most widely investigated structures because of their possible applications in high density magnetic recording media, sensor elements, and building blocks in biological transport systems. In this work, Iron nanowires have been prepared by electrodeposition technique using Anodized Aluminium Oxide (AAO) templates. The electrolyte used consisted of FeSO{sub 4.}6H{sub 2}O buffered with H{sub 3}BO{sub 3} and acidized by dilute H{sub 2}SO{sub 4}. FESEM analysis shows that the asdeposited nanowires are parallel to one another and have high aspect ratio with a reasonably high pore-filing factor. To fabricate the working electrode, a thin film of copper (∼ 220 nm thick) was coated on back side of AAO template by e-beam evaporation system to create electrical contact with the external circuit. The TEM results show that electrodeposited nanowires have diameter around 100 nm and are polycrystalline in structure. Magnetic properties show the existence of anisotropy for in and out of plane configuration. These nanowires have potential applications in magnetic data storage, catalysis and magnetic sensor applications.

Defects controlling electrical and optical properties of electrodeposited Bi doped Cu2O

Science.gov (United States)

Brandt, Iuri S.; Tumelero, Milton A.; Martins, Cesar A.; Plá Cid, Cristiani C.; Faccio, Ricardo; Pasa, André A.

2018-04-01

Doping leading to low electrical resistivity in electrodeposited thin films of Cu2O is a straightforward requirement for the construction of efficient electronic and energy devices. Here, Bi (7 at. %) doped Cu2O layers were deposited electrochemically onto Si(100) single-crystal substrates from aqueous solutions containing bismuth nitrate and cupric sulfate. X-ray photoelectron spectroscopy shows that Bi ions in a Cu2O lattice have an oxidation valence of 3+ and glancing angle X-ray diffraction measurements indicated no presence of secondary phases. The reduction in the electrical resistivity from undoped to Bi-doped Cu2O is of 4 and 2 orders of magnitude for electrical measurements at 230 and 300 K, respectively. From variations in the lattice parameter and the refractive index, the electrical resistivity decrease is addressed to an increase in the density of Cu vacancies. Density functional theory (DFT) calculations supported the experimental findings. The DFT results showed that in a 6% Bi doped Cu2O cell, the formation of Cu vacancies is more favorable than in an undoped Cu2O one. Moreover, from DFT data was observed that there is an increase (decrease) of the Cu2O band gap (activation energy) for 6% Bi doping, which is consistent with the experimental results.

Electrodeposition synthesis and electrochemical properties of nanostructured {gamma}-MnO{sub 2} films

Energy Technology Data Exchange (ETDEWEB)

Chou, Shulei; Cheng, Fangyi; Chen, Jun [Institute of New Energy Material Chemistry, Nankai University, Tianjin 300071 (China)

2006-11-08

The thin films of carambola-like {gamma}-MnO{sub 2} nanoflakes with about 20nm in thickness and at least 200nm in width were prepared on nickel sheets by combination of potentiostatic and cyclic voltammetric electrodeposition techniques. The as-prepared MnO{sub 2} nanomaterials, which were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), were used as the active material of the positive electrode for primary alkaline Zn/MnO{sub 2} batteries and electrochemical supercapacitors. Electrochemical measurements showed that the MnO{sub 2} nanoflake films displayed high potential plateau (around 1.0V versus Zn) in primary Zn/MnO{sub 2} batteries at the discharge current density of 500mAg{sup -1} and high specific capacitance of 240Fg{sup -1} at the current density of 1mAcm{sup -2}. This indicated the potential application of carambola-like {gamma}-MnO{sub 2} nanoflakes in high-power batteries and electrochemical supercapacitors. The growth process for the one- and three-dimensional nanostructured MnO{sub 2} was discussed on the basis of potentiostatic and cyclic voltammetric techniques. The present synthesis method can be extended to the preparation of other nanostructured metal-oxide films. (author)

Study on borate glass system containing with Bi2O3 and BaO for gamma-rays shielding materials: Comparison with PbO

International Nuclear Information System (INIS)

Kaewkhao, J.; Pokaipisit, A.; Limsuwan, P.

2010-01-01

In this work, the mass attenuation coefficients and shielding parameters of borate glass matrices containing with Bi 2 O 3 and BaO have been investigated at 662 keV, and compare with PbO in same glass structure. The theoretical values were calculated by WinXCom software and compare with experiential data. The results found that the mass attenuation coefficients were increased with increasing of Bi 2 O 3 , BaO and PbO concentration, due to increase photoelectric absorption of all glass samples. However, Compton scattering gives dominant contribution to the total mass attenuation coefficients for studied glass samples. Moreover the half value layers (HVL) of glass samples were also better than ordinary concretes and commercial window glass. These results reflecting that the Bi-based glass can use replace Pb in radiation shielding glass. In the case of Ba, may be can use at appropriate energy such as X-rays or lower.

The electrodeposition of multilayers on a polymeric substrate in flexible organic photovoltaic solar cells

Science.gov (United States)

Guedes, Andre F. S.; Guedes, Vilmar P.; Souza, Monica L.; Tartari, Simone; Cunha, Idaulo J.

2015-09-01

Flexible organic photovoltaic solar cells have drawn intense attention due to their advantages over competing solar cell technologies. The method utilized to deposit as well as to integrate solutions and processed materials, manufacturing organic solar cells by the Electrodeposition System, has been presented in this research. In addition, we have demonstrated a successful integration of a process for manufacturing the flexible organic solar cell prototype and we have discussed on the factors that make this process possible. The maximum process temperature was 120°C, which corresponds to the baking of the active polymeric layer. Moreover, the new process of the Electrodeposition of complementary active layer is based on the application of voltage versus time in order to obtain a homogeneous layer with thin film. This thin film was not only obtained by the electrodeposition of PANI-X1 on P3HT/PCBM Blend, but also prepared in perchloric acid solution. Furthermore, these flexible organic photovoltaic solar cells presented power conversion efficiency of 12% and the inclusion of the PANI-X1 layer reduced the effects of degradation on these organic photovoltaic panels induced by solar irradiation. Thus, in the Scanning Electron Microscopy (SEM), these studies have revealed that the surface of PANI-X1 layers is strongly conditioned by the dielectric surface morphology.

Development of CuInTe{sub 2} thin film solar cells by electrochemical route with low temperature (80 °C) heat treatment procedure

Energy Technology Data Exchange (ETDEWEB)

Lakhe, Manorama [Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune 411007 (India); Mahapatra, S.K. [Department of Applied Physics, Birla Institute of Technology, Mesra, Ranchi 835215 (India); Chaure, Nandu B., E-mail: n.chaure@physics.unipune.ac.in [Electrochemical Laboratory, Department of Physics, Savitribai Phule Pune University, Pune 411007 (India)

2016-02-15

Graphical abstract: Dark and illuminated J–V characteristic for Cell B, successively heat treated at 80 °C for 60 min and corresponding dV/d(J + J{sub L}) versus 1/(J + J{sub L}) plot. Efficiency, η = 3.8%, series resistance, R{sub s} = 43 Ω and ideality factor, n = 1.9 are measured for Cell B. - Highlights: • Temperature, 80 °C is sufficient to produce highly crystalline CuInTe{sub 2} thin films. • Stoichiometric, uniform and well adherent thin films of CuInTe{sub 2} were electrodeposited. • 3.8% efficiency was measured for a cell prepared by successive heat treatment at 80 °C. • ‘R{sub s}’ and ‘n’ investigated for Cell A and B were 47, 43 Ω and 2.0 and 1.9, respectively. - Abstract: The effect of successive low-temperature heat treatment on the properties of electrodeposited CuInTe{sub 2} (CIT) thin films is investigated. The electrodeposition potential, −0.8 V versus Ag/AgCl was optimized by cyclic voltammetry onto CdS coated Fluorine doped tin oxide substrate. The samples were successively heat treated at 80 °C for 5, 30 and 60 min in an air ambient. The structural, morphological, compositional, electrical and optoelectronic properties were studied using XRD, Raman spectroscopy, SEM, FESEM, EDS, Current–Voltage and Capacitance–Voltage measurements. As-prepared CIT film exhibited amorphous nature, whereas the systematic development in the crystallinity was observed in successively heat treated samples. Compact, densely packed, globular surface morphology was observed. The Cu/In ratio was found to be increased systematically from 0.60 to 0.82 with heat treatment duration. The solar cell devices successively heat treated at 80 °C for 30 and 60 min measured an efficiency (η), 3.4% and 3.8%, respectively.

Electrochemical synthesis, structure and phase composition of nano structured amorphous thin layers of NiW and Ni-Mo

International Nuclear Information System (INIS)

Vitina, I.; Lubane, M.; Belmane, V.; Rubene, V.; Krumina, A.

2006-01-01

Full text: Nano structured Ni-W thin layers containing W 6-37 wt.% were electrodeposited on a copper substratum. The W content in the layer changes, and it is determined by the electrolyte pH in the range 8.0-9.6 and the cathode current density in the range 1.0-10.0 A/dm 2 . The atomic composition and thermal stability of structure of the electrodeposited thin layers depend for the most part on the conditions of the electrodeposition and less on the W content in the layer. Cracking of the Ni-W layers electrodeposited at the electrolyte pH 8.5 and containing 34-37 wt.% W and 8.5 wt.% W was observed. The cracking increases at heating at 400 deg C for 50 h. On the contrary, no cracking of the Ni-W layer electrodeposited at the electrolyte pH 9.0 and containing 25 wt.% W was observed. The atomic composition of the layer remains practically unchanged at heating at 400 deg C for 50 h. The layer binds oxygen up to 7 wt.%. According to X-ray diffraction, in spite of the W content 35-37 wt.% in the layer, nano structured layers rather than amorphous layers were obtained which at heating at 400 deg C depending on the W content crystallises as Ni or intermetallic compounds Ni x W y if the W content is approx. 25 wt.%. Amorphous Ni-Mo alloys containing 35-52 wt.% Mo was electrodeposited on copper substratum at the cathode current densities of 0.5-1.5 A/dm2 and the electrolyte pH 6.8-8.6. Formation of thin layer (∼1-2μm) of X-ray amorphous Ni-Mo alloy, the Mo content, the characteristics of structure depend on the electrodeposition process, the electrolyte pH, and the cathode current density. The Ni-Mo layer deposited at the electrolyte pH above 8.6 and below average 6.8 had a nanocrystalline structure rather than characteristics of amorphous structure. Ni- W and Ni-Mo alloys were electrodeposited from citrate electrolyte not containing ammonium ions

Development of Electrodeposited Zn/nano-TiO2 Composite Coatings with Enhanced Corrosion Performance

Science.gov (United States)

Benea, L.; Dănăilă, E.

2017-06-01

Pure zinc coatings have been found ineffective when are used in aggressive environments such as those which contain chlorides or industrial pollutants [1]. In this paper, Zn/nano-TiO2 composite coatings with various contents of TiO2 nanoparticles (diameter size of 10 nm) were prepared on low-carbon steel by electro-codeposition technique. The deposition was carried out at different cathodic potentials ranging from -1600 mV to -2100 mV for different deposition times between 5-15 min. Pure Zn coatings were also produced under the same experimental conditions for comparison. Present work aims to investigate the effects of selected electrodeposition parameters (cathodic potential, TiO2 nanoparticle concentration in the plating bath and electrodeposition time) on the corrosion behavior of electrodeposited Zn/nano-TiO2 composite obtained. The corrosion experiments were performed in natural seawater, using electrochemical methods such as open circuit potential, potentiodynamic polarization and linear polarization resistance. The results showed that the inclusion of TiO2 nanoparticles into zinc matrix lead to an improved corrosion resistance comparatively with pure zinc coatings obtained under similar conditions.

Electrodeposition synthesis of MnO{sub 2}/TiO{sub 2} nanotube arrays nanocomposites and their visible light photocatalytic activity

Energy Technology Data Exchange (ETDEWEB)

Xu, Xuyao [School of Chemistry Science and Technology, and Institute of Physical Chemistry, Zhanjiang Normal University, Zhanjiang 524048 (China); Zhou, Xiaosong, E-mail: zxs801213@163.com [School of Chemistry Science and Technology, and Institute of Physical Chemistry, Zhanjiang Normal University, Zhanjiang 524048 (China); Li, Xiaoyu, E-mail: lixiaoyu@iga.ac.cn [Key Laboratory of Wetland Ecology and Environment, Northeast Institute of Geography and Agroecology, Chinese Academy of Science, Changchun 130012 (China); Yang, Fei [The State Key Laboratory of Resources and Environmental Information System, Institute of Geographic Sciences and Natural Resources Research of Chinese Academy of Sciences, 11A, Datun Road, Chaoyang District, Beijing 100101 (China); Jin, Bei; Xu, Tan; Li, Guosheng; Li, Manyi [School of Chemistry Science and Technology, and Institute of Physical Chemistry, Zhanjiang Normal University, Zhanjiang 524048 (China)

2014-11-15

Highlights: • MnO{sub 2}/TiO{sub 2} nanotube arrays nanocomposites are prepared by electrodeposition. • MnO{sub 2}/TiO{sub 2} exhibits high visible light photocatalytic activity. • The results of XRD show the depositions are attributed to α-MnO{sub 2}. • A photocatalytic mechanism is discussed under visible light irradiation. - Abstract: MnO{sub 2}/TiO{sub 2} nanotube arrays nanocomposite photocatalysts have been synthesized through an electrodeposition method. X-ray powder diffraction analysis and X-ray photoelectron spectroscopy measurements reveal that the products of electrodeposition method are MnO{sub 2}. Scanning electron microscopy measurements suggest that the depositions are deposited on the surface or internal of the nanotube. UV–vis light absorbance spectra demonstrate the excellent adsorption properties of MnO{sub 2}/TiO{sub 2} over the whole region of visible light, which enables this novel photocatalytic material to possess remarkable activity in the photocatalytic degradation of acid Orange II under visible light radiation. Moreover, a possible photocatalytic mechanism is discussed.

Preparation of thin arsenic and radioarsenic targets for neutron capture studies

International Nuclear Information System (INIS)

Fassbender, M.; Bach, H.; Bond, E.; Nortier, F.M.; Vieira, D.

2009-01-01

A simple method for the electrodeposition of elemental arsenic (As) on a metal backing from aqueous solutions has been developed. The method was successfully applied to stable As ( 75 As). Thin (2.5 mg cm -2 ) coherent, smooth layers of the metalloid on Ti foils (2.5 μm thickness) were obtained. Electrodeposits served as targets for 75 As(n,γ) 76 As neutron capture experiments at Los Alamos Neutron Science Center (LANSCE). Respective 73 As(n,γ) 74 As experiments are planned for the near future, and 73 As targets will be prepared in a similar fashion utilizing the new electrodeposition method. The preparation of an 73 As (half-life 80.3 days) plating bath solution from proton irradiated germanium has been demonstrated. Germanium target irradiation was performed at the Los Alamos Isotope Production Facility (IPF). (author)

Using the particle beam optics lab. (PBO LABtm) for beamline design and analysis

International Nuclear Information System (INIS)

Gillespie, G.H.; Hill, B.W.; Martono, H.; Moore, J.M.; Lampel, M.C.; Brown, N.A.

1999-01-01

The Particle Beam Optics Interactive Computer Laboratory (PBO Lab) represents a new approach to providing software for particle beam optics modeling. The PBO Lab includes four key elements: a graphic user interface shell; a graphic beamline construction kit for users to interactively and visually construct optical beam lines; a knowledge database on the physics and technology of optical elements, and various charged particle optics computational engines. A first-order matrix code, including a space charge model, can be used to produce scaled images of beamlines together with overlays of single trajectories and beam envelopes. The qualitative results of graphically sliding beamline components, or adjusting bend angles, can be explored interactively. Quantitative computational engines currently include the third-order TRANSPORT code and the multi-particle ray tracing program TURTLE. The use of the PBO Lab for designing and analyzing a second order achromatic bend is illustrated with the Windows 95/NT version of the software. (authors)

Enhanced photoelectrocatalytic performance of α-Fe2O3 thin films by surface plasmon resonance of Au nanoparticles coupled with surface passivation by atom layer deposition of Al2O3.

Science.gov (United States)

Liu, Yuting; Xu, Zhen; Yin, Min; Fan, Haowen; Cheng, Weijie; Lu, Linfeng; Song, Ye; Ma, Jing; Zhu, Xufei

2015-12-01

The short lifetime of photogenerated charge carriers of hematite (α-Fe2O3) thin films strongly hindered the PEC performances. Herein, α-Fe2O3 thin films with surface nanowire were synthesized by electrodeposition and post annealing method for photoelectrocatalytic (PEC) water splitting. The thickness of the α-Fe2O3 films can be precisely controlled by adjusting the duration of the electrodeposition. The Au nanoparticles (NPs) and Al2O3 shell by atom layer deposition were further introduced to modify the photoelectrodes. Different constructions were made with different deposition orders of Au and Al2O3 on Fe2O3 films. The Fe2O3-Au-Al2O3 construction shows the best PEC performance with 1.78 times enhancement by localized surface plasmon resonance (LSPR) of NPs in conjunction with surface passivation of Al2O3 shells. Numerical simulation was carried out to investigate the promotion mechanisms. The high PEC performance for Fe2O3-Au-Al2O3 construction electrode could be attributed to the Al2O3 intensified LSPR, effective surface passivation by Al2O3 coating, and the efficient charge transfer due to the Fe2O3-Au Schottky junctions.

Fabrication of ruthenium thin film and characterization of its chemical mechanical polishing process

International Nuclear Information System (INIS)

Chou, Yi-Sin; Yen, Shi-Chern; Jeng, King-Tsai

2015-01-01

The fabrication of Ru thin film is conducted on titanium (Ti)-based rotating disk electrodes (RDE) by electrodeposition and characteristics of its chemical mechanical polishing (CMP) are investigated to be employed for copper diffusion layer applications in various semiconductor-device interconnects. The electrodeposits obtained under different electrodeposition conditions are characterized using atomic force microscope (AFM) and field emission scanning electron microscope (FESEM). Experimental results indicate that the Ru electrodeposition exhibits a Tafel behavior with a 2e metal ion reduction process. Both exchange current density and cathodic transfer coefficient are determined. A quasi Koutecky–Levich analysis is proposed to analyze the electrodeposition processes under different applied current density conditions and the activation overpotentials together with electrodeposition rate constants are obtained. For Ru CMP operations, slurries containing metal-free 2wt% ammonium persulfate and 2wt% silica abrasive at various pH values are employed. Potentiodynamic polarization studies indicate that the corrosion current density varies in the presence of ammonia while the static etch rate remains low. Both chemical and mechanical effects are investigated and analyzed, and the CMP efficacy factors are obtained. - Highlights: • Ru electrodeposition is a 2e metal ion reduction process with Tafel behavior. • Ru electrodeposition on Ti RDE fits a quasi Koutecky–Levich equation. • Metal-free slurry is employed for CMP operation to avoid contamination. • The Ru CMP process is affected by the surface condition and the pH of slurry. • The CMP efficacy factor should be high in order to obtain a smooth surface

Fabrication of ruthenium thin film and characterization of its chemical mechanical polishing process

Energy Technology Data Exchange (ETDEWEB)

Chou, Yi-Sin [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Yen, Shi-Chern, E-mail: scyen@ntu.edu.tw [Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan (China); Jeng, King-Tsai [Research Division I, TIER, 7F, No. 16-8, Dehuei St., Taipei 10461, Taiwan (China)

2015-07-15

The fabrication of Ru thin film is conducted on titanium (Ti)-based rotating disk electrodes (RDE) by electrodeposition and characteristics of its chemical mechanical polishing (CMP) are investigated to be employed for copper diffusion layer applications in various semiconductor-device interconnects. The electrodeposits obtained under different electrodeposition conditions are characterized using atomic force microscope (AFM) and field emission scanning electron microscope (FESEM). Experimental results indicate that the Ru electrodeposition exhibits a Tafel behavior with a 2e metal ion reduction process. Both exchange current density and cathodic transfer coefficient are determined. A quasi Koutecky–Levich analysis is proposed to analyze the electrodeposition processes under different applied current density conditions and the activation overpotentials together with electrodeposition rate constants are obtained. For Ru CMP operations, slurries containing metal-free 2wt% ammonium persulfate and 2wt% silica abrasive at various pH values are employed. Potentiodynamic polarization studies indicate that the corrosion current density varies in the presence of ammonia while the static etch rate remains low. Both chemical and mechanical effects are investigated and analyzed, and the CMP efficacy factors are obtained. - Highlights: • Ru electrodeposition is a 2e metal ion reduction process with Tafel behavior. • Ru electrodeposition on Ti RDE fits a quasi Koutecky–Levich equation. • Metal-free slurry is employed for CMP operation to avoid contamination. • The Ru CMP process is affected by the surface condition and the pH of slurry. • The CMP efficacy factor should be high in order to obtain a smooth surface.

2010 ELECTRODEPOSITION GORDON RESEARCH CONFERENCE, AUGUST 1-6, 2010

Energy Technology Data Exchange (ETDEWEB)

Peter Searson

2010-08-06

The 2010 Gordon Conference on Electrodeposition will present cutting-edge research on electrodeposition with emphasis on (i) advances in basic science, (ii) developments in next-generation technologies, and (iii) new and emerging areas. The Conference will feature a wide range of topics, from atomic scale processes, nucleation and growth, thin film deposition, and electrocrystallization, to applications of electrodeposition in devices including microelectronics, solar energy, and power sources. The Conference will bring together investigators from a wide range of scientific disciplines, including chemical engineering, materials science and engineering, physics, and chemistry. The Conference will feature invited speakers at the forefront of the field, and a late-breaking news session that will provide the opportunity for graduate students, post-docs, and junior faculty to participate. The collegial atmosphere of this Conference, with scientific talks and poster sessions, as well as opportunities for informal gatherings in the afternoons and evenings, provides an avenue for scientists from different disciplines to discuss current issues and promotes cross-disciplinary collaborations in the various research areas represented. The Conference will be held at Colby-Sawyer College, located in the Mt. Kearsarge-Lake Sunapee Region of New Hampshire. The surrounding mountains, forests, and lakes provide a beautiful setting for this conference. The attendance is limited so early application is strongly advised.

Preparation of porous lead from shape-controlled PbO bulk by in situ electrochemical reduction in ChCl-EG deep eutectic solvent

Science.gov (United States)

Ru, Juanjian; Hua, Yixin; Xu, Cunying; Li, Jian; Li, Yan; Wang, Ding; Zhou, Zhongren; Gong, Kai

2015-12-01

Porous lead with different shapes was firstly prepared from controlled geometries of solid PbO bulk by in situ electrochemical reduction in choline chloride-ethylene glycol deep eutectic solvents at cell voltage 2.5 V and 353 K. The electrochemical behavior of PbO powders on cavity microelectrode was investigated by cyclic voltammetry. It is indicated that solid PbO can be directly reduced to metal in the solvent and a nucleation loop is apparent. Constant voltage electrolysis demonstrates that PbO pellet can be completely converted to metal for 13 h, and the current efficiency and specific energy consumption are about 87.79% and 736.82 kWh t-1, respectively. With the electro-deoxidation progress on the pellet surface, the reduction rate reaches the fastest and decreases along the distance from surface to inner center. The morphologies of metallic products are porous and mainly consisted of uniform particles which connect with each other by finer strip-shaped grains to remain the geometry and macro size constant perfectly. In addition, an empirical model of the electro-deoxidation process from spherical PbO bulk to porous lead is also proposed. These findings provide a novel and simple route for the preparation of porous metals from oxide precursors in deep eutectic solvents at room temperature.

Thin-Film Materials Synthesis and Processing Facility

Data.gov (United States)

Federal Laboratory Consortium — FUNCTION: Provides a wide capability for deposition and processing of thin films, including sputter and ion-beam deposition, thermal evaporation, electro-deposition,...

Substrate type < 111 >-Cu{sub 2}O/<0001 >-ZnO photovoltaic device prepared by photo-assisted electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Zamzuri, Mohd, E-mail: zamzuri@tf.me.tut.ac.jp [Department of Mechanical Eng., Toyohashi University of Technology, 1-1 Hibari Gaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan); School of Manufacturing Eng., Universiti Malaysia Perlis, Kampus Tetap Pauh Putra, Jln Arau-Changlun, 02600 Arau, Perlis (Malaysia); Sasano, Junji [Department of Mechanical Eng., Toyohashi University of Technology, 1-1 Hibari Gaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan); Mohamad, Fariza Binti [Faculty of Electrical & Electronic Eng., University Tun Hussein Onn Malaysia, 86400, Parit Raja, Batu Pahat, Johor (Malaysia); Izaki, Masanobu [Department of Mechanical Eng., Toyohashi University of Technology, 1-1 Hibari Gaoka, Tempaku, Toyohashi, Aichi 441-8580 (Japan)

2015-11-30

The substrate-type < 0001 > ZnO/<111 > Cu{sub 2}O photovoltaic (PV) device has been constructed by electrodeposition of a < 111 >-p-Cu{sub 2}O layer on an Au(111)/Si wafer substrate followed by stacking the n-ZnO layer by electrodeposition during light irradiation in aqueous solutions. The PV device was fabricated by stacking the Al:ZnO-window by sputtering and the top Al electrode by vacuum evaporation. The < 0001 >-ZnO layer was composed of aggregates of hexagonal columnar grains grown in the direction normal to the surface, and pores could be observed between the ZnO grains at the deposition time last 1800 s. The < 0001 >-ZnO/<111 >-Cu{sub 2}O PV device showed a photovoltaic performance under AM1.5 illumination, and showed the improved short-circuit current density of 5.87 mA cm{sup −2} by stacking the AZO-TCO due to the increase in the diffusion length of the carrier. - Highlights: • Substrate type ZnO/Cu{sub 2}O photovoltaic devices only by electrodeposition • ZnO layer was stacked on the Cu{sub 2}O layer by photo-assisted electrodeposition. • AZO/ZnO/Cu{sub 2}O photovoltaic devices with a short-circuit current density of 5.87 mA cm{sup −2}.

Rocking disc electro-deposition of copper films on Mo/MoSe{sub 2} substrates

Energy Technology Data Exchange (ETDEWEB)

Cummings, Charles Y.; Frith, Paul E. [Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom); Zoppi, Guillaume; Forbes, Ian [Northumbria Photovoltaics Applications Centre, Northumbria University, NE1 8ST (United Kingdom); Rogers, Keith D. [Cranfield Health, Cranfield University, Shrivenham Campus, Swindon, SN6 8LA (United Kingdom); Lane, David W. [Department of Applied Science, Security and Resilience, Cranfield University, Shrivenham, Swindon, SN6 8LA (United Kingdom); Marken, Frank, E-mail: F.Marken@bath.ac.uk [Department of Chemistry, University of Bath, Claverton Down, Bath BA2 7AY (United Kingdom)

2011-08-31

A novel electro-deposition method based on a rocking disc system with {pi}/3 amplitude and variable frequency is introduced. Uniform copper films were deposited from a 0.1 M CuSO{sub 4}/3.0 M NaOH/0.2 M sorbitol bath directly onto 12.1 cm{sup 2} Mo/MoSe{sub 2} substrates with X-ray diffraction showing a thickness variation of {+-}5% over this area. Investigation of the mass transport conditions suggests (i) uniform diffusion over the sample, (ii) a rate of mass transport proportional to the square root of the rocking rate, and (iii) turbulent conditions, which are able to dislodge gas bubbles during electro-deposition.

Optical properties of zinc oxide-based ternary compounds synthesized by electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Cembrero, J. [Departament d' Enginyeria Mecanica i Materials, Universitat Politecnica de Valencia, Cami de Vera s/n, 46022 Valencia (Spain); Mollar, M.; Tortosa, M. [Departament de Fisica Aplicada, Universitat Politecnica de Valencia, Cami de Vera s/n, 46022 Valencia (Spain); Mari, B.

2008-07-01

Structure, morphology and optical properties of ZnO thin films grown by electrodeposition under different conditions changing both solvent (water or dimethylsulfoxide) and substrate (polycrystalline FTO or monocrystalline GaN) are reported. The results point out the advantage of using dimethylsulfoxide when uniform, oriented and highly transparent films are required. On the other hand electrodeposition in aqueous bath produces perfectly defined hexagonal ZnO columns which can be fully oriented by chosing a suitable substrate. Photoluminescence has only been observed for ZnO films grown in aqueous bath. Ternary compounds as ZnMO (M=Cd,Co,Mn) with a controlled ratio between both cations, and morphology and structure like binary ZnO can be easily obtained from dimethylsulfoxide. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Electrodeposition of silver nanoparticle arrays on transparent conductive oxides

International Nuclear Information System (INIS)

Zhang, Dezhong; Tang, Yang; Jiang, Fuguo; Han, Zhihua; Chen, Jie

2016-01-01

Highlights: • The sliver nanoparticles' size and the distance between nanoparticles are tunable. - Abstract: In this paper, we present a facile method for the preparation of silver nanoparticles on aluminum-doped zinc oxide (AZO) via electrodeposition techniques at room temperature. The morphology and structure of silver nanoparticles are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), respectively. Due to localized surface plasmon resonances, as-prepared silver nanoparticles on AZO glass exhibited different reflectivity in contrast with bare AZO glass. The weighted reflection of AZO substrate increased from 10.2% to 12.8%. The high reflection property of silver nanoparticle arrays on AZO substrate might be applicable for thin film solar cells and other optoelectronics applications.

Electrodeposition of silver nanoparticle arrays on transparent conductive oxides

Energy Technology Data Exchange (ETDEWEB)

Zhang, Dezhong; Tang, Yang, E-mail: tangyang@nicenergy.com; Jiang, Fuguo; Han, Zhihua; Chen, Jie

2016-04-30

Highlights: • The sliver nanoparticles' size and the distance between nanoparticles are tunable. - Abstract: In this paper, we present a facile method for the preparation of silver nanoparticles on aluminum-doped zinc oxide (AZO) via electrodeposition techniques at room temperature. The morphology and structure of silver nanoparticles are characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), respectively. Due to localized surface plasmon resonances, as-prepared silver nanoparticles on AZO glass exhibited different reflectivity in contrast with bare AZO glass. The weighted reflection of AZO substrate increased from 10.2% to 12.8%. The high reflection property of silver nanoparticle arrays on AZO substrate might be applicable for thin film solar cells and other optoelectronics applications.

The influence of Fe2+ concentration and deposition time on the corrosion resistance of the electrodeposited zinc–nickel–iron alloys

Directory of Open Access Journals (Sweden)

M.M. Abou-Krisha

2016-11-01

Full Text Available Electrodeposition operating conditions for Zn–Ni–Fe alloys from sulfate baths and the corrosion resistance of the electrodeposited alloys were studied. The comparison between Zn–Ni and Zn–Ni–Fe alloys co-deposition revealed that the remarkable inhibition of Ni and Fe deposition takes place due to the presence of Zn2+ in the plating bath. The electrodeposition was performed on the steel substrate, under galvanostatic conditions, for varying Fe2+ bath concentrations and at different times. X-ray diffraction studies of the deposit showed the presence of Fe3Ni2 phase and γ-phase with a composition of Ni2Zn11. The obtained data also exposed that the corrosion resistance increases as a result of increasing Fe2+ concentration and deposition time. Investigation was carried out using cyclic voltammetry and galvastatic techniques for electrodeposition, while linear polarization resistance and anodic linear sweeping voltammetry techniques were used for corrosion study.

Synthesis and characterization of a PbO2-clay nanocomposite: Removal of lead from water using montmorillonite

International Nuclear Information System (INIS)

Aroui, L.; Zerroual, L.; Boutahala, M.

2012-01-01

Graphical abstract: The replacement of Na by Pb in the interlayer space of the smectite leads to a decrease in the intensity of the the (0 0 1) reflection as the concentration of lead nitrate increases. A significant restructuring at the particle scale is observed leading probably to the exfoliation of the caly. In addition, the thermal behaviour of the montmorillonite samples with regard to their dehydration and dehydroxilation capacities is significantly influenced. This leads to a lowering of the water content and a decrease in the ionic conductivity of the clay. Highlights: ► In the clay, Pb replaces Na ions and a significant restructuring at the particle scale is observed. ► Pb influenced significantly the thermal behaviour of the clay with regard to its dehydration. ► In the interlayer space, the exchange of Na by Pb leads to a decrease in the protonic conductivity. ► A PbO 2 -clay nanocomposite material with good conductivity is synthesized. -- Abstract: The aim of this paper is to present the results obtained with Pb(II) sorption on an Algerian Clay. The experiments were carried out using a batch process. Powder X-rays diffraction patterns (PXRD) prove that in the montmorillonite Pb replaces Na ions. A significant restructuring at the particle scale is observed leading to the disappearance of the d 001 reflection of the clay at high concentrations of lead. The replacement of hydrated Na with Pb ions influenced significantly the thermal behaviour of the montmorillonite samples with regard to their dehydration and dehydroxilation capacities with a lowering of the water content. A PbO 2 -clay composite material with good electrical conductivity is synthesized.

Electrochemical growth and studies of CuInSe2 thin films

International Nuclear Information System (INIS)

Prasher, Dixit; Chandel, Tarun; Rajaram, Poolla

2014-01-01

Thin films of CuInSe 2 were grown on fluorine doped tin oxide (<10 Ω/□) coated glass using the electrodeposition technique. The electrodeposition was carried out potentiostatically using an aqueous bath consisting of solutions of CuCl 2 , InCl 3 and SeO 2 with ethylenediamine-dihydrochloride (EDC) added for complexation. CuInSe 2 films were also deposited without using any complexing agent in the bath. To improve the crystallinity the CuInSe 2 films were annealed in vaccum at 300 °C for one hour. The annealed films were analyzed by x-ray diffraction, transmission electron microscopy (TEM), scanning electron microscopy (SEM), energy dispersive analysis of x-rays (EDAX), atomic force microscopy (AFM) and optical spectra. The results obtained in this work show that by adding a suitable complexing agent to the electrochemical bath, nanocrystalline CuInSe 2 , 20 nm to 30 nm in size, can be grown. The composition of the CuInSe 2 films can be controlled by means of the bath composition and stoichiometric films can be obtained for a bath with ionic Cu:In:Se composition close to 1:4:2. AFM micrographs show that the particles are generally oval shaped for near stoichiometric compositions. However for extreme copper rich layers, the morphology is completely different, the particles in this case appearing in the form of nanoflakes. Each flake has a thickness in the nano range, but the surface extends to a length of several microns. (papers)

Laterally enhanced growth of electrodeposited Au to form ultrathin films on nonconductive surfaces

International Nuclear Information System (INIS)

Kobayashi, Chiaki; Saito, Mikiko; Homma, Takayuki

2012-01-01

We investigated the laterally enhanced growth of electrodeposited Au for fabricating nanogap electrodes. To enhance the lateral growth, we carried out electrodeposition over patterned electrodes onto a SiO 2 surface modified with self-assembled monolayers (SAMs) or dendrimers with amine groups. The morphology and thickness of the Au films were controlled by adjusting deposition conditions such as duration, applied potential, and Au ion concentration in the bath. To investigate the mechanism of the laterally enhanced growth, the surface states of SAM- or dendrimer-modified SiO 2 were analyzed by X-ray photoelectron spectroscopy (XPS). The XPS results indicate the existence of organic molecules and Au ions on the SiO 2 surface, which suggests that laterally enhanced growth is induced by the Au ions coordinated on the amine groups of the organic molecules. To further analyze the mechanism of the laterally enhanced growth, we investigated the relationship between the morphology of the laterally enhanced growth of Au and the amount of Au ions on organic molecules. The laterally enhanced growth of Au is expected to be useful for fabricating thin film nanogap electrodes.

New insight into the mechanism of cathodic electrodeposition of zinc oxide thin films onto vitreous carbon

OpenAIRE

Ait Ahmed , N.; Eyraud , M.; Hammache , H.; Vacandio , F.; Sam , S.; Gabouze , N.; Knauth , P.; Pelzer , K.; Djenizian , T.

2014-01-01

International audience; In this study, the mechanism of zinc oxide (ZnO) electrodeposition from aqueous zinc nitrate solution at 70°C was investigated on vitreous carbon and bulk zinc electrodes using cyclic voltammetry experiments. Mechanisms are presented for the ZnO formation: the first widely accepted route corresponds to ZnO precipitation from Zn 2+ and OH-produced by NO3-reduction; the second route, which is discussed in this article, is due to Zn 2+ reduction into metallic Zn followed ...

Structural and optical properties of electrodeposited molybdenum oxide thin films

International Nuclear Information System (INIS)

Patil, R.S.; Uplane, M.D.; Patil, P.S.

2006-01-01

Electrosynthesis of Mo(IV) oxide thin films on F-doped SnO 2 conducting glass (10-20/Ω/□) substrates were carried from aqueous alkaline solution of ammonium molybdate at room temperature. The physical characterization of as-deposited films carried by thermogravimetric/differential thermogravimetric analysis (TGA/DTA), infrared spectroscopy and X-ray diffraction (XRD) showed the formation of hydrous and amorphous MoO 2 . Scanning electron microscopy (SEM) revealed a smooth but cracked surface with multi-layered growth. Annealing of these films in dry argon at 450 deg. C for 1 h resulted into polycrystalline MoO 2 with crystallites aligned perpendicular to the substrate. Optical absorption study indicated a direct band gap of 2.83 eV. The band gap variation consistent with Moss rule and band gap narrowing upon crystallization was observed. Structure tailoring of as-deposited thin films by thermal oxidation in ambient air to obtain electrochromic Mo(VI) oxide thin films was exploited for the first time by this novel route. The results of this study will be reported elsewhere

Influence of ZrO2 particles on fluorine-doped lead dioxide electrodeposition process from nitrate bath

International Nuclear Information System (INIS)

Yao, Yingwu; Zhou, Tao; Zhao, Chunmei; Jing, Qiming; Wang, Yang

2013-01-01

The influence of ZrO 2 particles on fluorine-doped lead dioxide electrodeposition process on the glass carbon electrode (GCE) from lead nitrate electrolytes was studied by cyclic voltammetry (CV) and chronoamperometry (CA), coupled with the scanning electron microscope (SEM). Instantaneous nucleation mechanism is found for fluorine-doped lead dioxide electrodeposition in the presence of ZrO 2 particles according to Scharifker–Hills’ model with three-dimensional growth. The results show that the addition of ZrO 2 particles decrease the active surface area of the GCE, and the growth of the lead dioxide crystallites was obstructed

Effect of Magnetic Field on Surface Morphology and Magnetic Properties of FeCu/Cu Nano layers Prepared by Electrodeposition Technique: Investigation of Magneto-hydrodynamic Effect

Directory of Open Access Journals (Sweden)

M. Merikhi

2015-10-01

Full Text Available In this paper, the effect of magnetic field on the morphology, structure and magnetic properties of electrodeposited FeCu/Cu thin films was investigated. The films were deposited on Au2PdAg/glass substrates using electrodeposition technique in potentiostatic control. The magnetic fields of 5000 and 7000 Oe were applied on deposition bath during deposition. Two series of thin films were prepared in the same deposition conditions, one in the presence and the other in absence of magnetic field and the products were compared. The results indicate that applying the magnetic field has a significant effect on the growth process, i.e. morphology, crystal structure and magnetic properties of the films. The morphology and structure of the FeCu/Cu Nano layers were studied using X-ray diffraction (XRD and scanning electron microscopy (SEM. The weight percentages of the elements in the deposited multilayers were determined by energy dispersive X-ray spectroscopy (EDS. Magnetic properties of thin films were studied using the vibrating sample magnetometer (VSM.

Electrodeposition of WO3 nanoparticles into surface mounted metal-organic framework HKUST-1 thin films

Science.gov (United States)

Yoo, Hyeonseok; Welle, Alexander; Guo, Wei; Choi, Jinsub; Redel, Engelbert

2017-03-01

We describe a novel procedure to fabricate WO3@surface-mounted metal-organic framework (SURMOF) hybrid materials by electrodeposition of WO3 nanoparticles into HKUST-1, also termed Cu3(BTC)2 SURMOFs. These materials have been characterized using x-ray diffraction, time-of-flight secondary ion mass spectrometry, scanning electron microscopy, x-ray photoelectron spectroscopy as well as linear sweep voltammetry. The WO3 semiconductor/SURMOF heterostructures were further tested as hybrid electrodes in their performance for hydrogen evolution reaction from water.

Lithographically patterned electrodeposition of gold, silver, and nickel nanoring arrays with widely tunable near-infrared plasmonic resonances.

Science.gov (United States)

Halpern, Aaron R; Corn, Robert M

2013-02-26

A novel low-cost nanoring array fabrication method that combines the process of lithographically patterned nanoscale electrodeposition (LPNE) with colloidal lithography is described. Nanoring array fabrication was accomplished in three steps: (i) a thin (70 nm) sacrificial nickel or silver film was first vapor-deposited onto a plasma-etched packed colloidal monolayer; (ii) the polymer colloids were removed from the surface, a thin film of positive photoresist was applied, and a backside exposure of the photoresist was used to create a nanohole electrode array; (iii) this array of nanoscale cylindrical electrodes was then used for the electrodeposition of gold, silver, or nickel nanorings. Removal of the photoresist and sacrificial metal film yielded a nanoring array in which all of the nanoring dimensions were set independently: the inter-ring spacing was fixed by the colloidal radius, the radius of the nanorings was controlled by the plasma etching process, and the width of the nanorings was controlled by the electrodeposition process. A combination of scanning electron microscopy (SEM) measurements and Fourier transform near-infrared (FT-NIR) absorption spectroscopy were used to characterize the nanoring arrays. Nanoring arrays with radii from 200 to 400 nm exhibited a single strong NIR plasmonic resonance with an absorption maximum wavelength that varied linearly from 1.25 to 3.33 μm as predicted by a simple standing wave model linear antenna theory. This simple yet versatile nanoring array fabrication method was also used to electrodeposit concentric double gold nanoring arrays that exhibited multiple NIR plasmonic resonances.

Electrochemical synthesis of photoactive In/sub 2/Se/sub 3/ thin films

Energy Technology Data Exchange (ETDEWEB)

Herrero, J; Ortega, J

1987-12-01

In/sub 2/Se/sub 3/ thin films were grown by alternate electrodeposition of selenium and indium from separate baths onto titanium substrates with subsequent thermal annealing. The influence of annealing temperature on the properties of the obtained films was examined. The results of X-ray diffraction patterns led to the conclusion that films were ..beta..-phase when the temperature ranged between 300 and 500/sup 0/C. At 600/sup 0/C the thin film loses Se and the ratio Se/In decreases. Only photoanodic response, n-type thin films, was observed when the samples were tested in a photoelectrochemical cell with a sulfite/sulfate redox couple. Values of the photocurrent on the spectra response were increased when the annealing temperature was also increased, showing the best photocurrent values at 500/sup 0/C, and the films that were annealed at 600/sup 0/C showed no photoactivity. Spectral responses after chemical etching of the samples showed a significant increase of the photocurrent. Application of Gaertner-Butler's model to the interface semiconductor-electrolyte makes it possible to obtain the semiconductor energy gap, on samples heated at 500/sup 0/C, corresponding to a direct allowed band transition.

Influence of co-electrodeposited Gold particles on the electrocatalytic properties of CoHCF thin films

International Nuclear Information System (INIS)

Kumar, Alam Venugopal Narendra; Joseph, James

2014-01-01

The electrochemical modification of solid electrodes with metal hexacyanoferrate thin films for enhancing the interfacial properties has created interest for over the past three decades. The preparation of Prussian blue (PB) Au nano composites for the enhancement in the electrocatalytic properties of PB on glassy carbon electrode has been reported by us. The incorporation of Au nano particles in Cobalt hexacyanoferrate (CoHCF) films on Glassy carbon by co-electrodeposition is expected to benefit its interfacial electron transfer properties. The present work describes the effect on the interfacial properties by incorporated Au particles in CoHCF (CoHCF(Au)) modified electrodes. The CoHCF(Au) modified electrodes were characterized by UV-Vis spectrophotometry, Cyclic Voltammetry, AC Impedance, FE-SEM etc., Influence on the electrocatalytic properties of CoHCF(Au) films have been explored by performing two important reactions i) Hydrazine elecrtro-oxidation ii) Oxygen evolution reaction. Our results reveal that CoHCF(Au) modified GC electrode perform better in terms of charge transport in the redox film and also for the electrooxidation of hydrazine in comparision with simple CoHCF modified electrodes. By using the current-transient technique (chrono method i vs t curve) the hydrazine diffusion coefficient (D 0 ) were calculated. Diffusion coefficient of hydrazine was approximately three times higher on CoHCF(Au) electrode, 9.5 × 10 −5 cm 2 s −1 compared with simple CoHCF modified electrode, 3.3× 10 −5 cm 2 s −1 . Similarly, we also discuss results which reveal that CoHCF(Au) electrodes enhances electrocatalytic activity in splitting water to oxygen in 0.1 M NaOH solution compared to simple CoHCF and Au deposited on GC electrodes

Nanostructured ‘Anastacia’ flowers for Zn coating by electrodepositing ZnO at room temperature

Energy Technology Data Exchange (ETDEWEB)

Alves, Marta M., E-mail: martamalves@tecnico.ulisboa.pt [ICEMS Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001, Lisboa (Portugal); Santos, Catarina F.; Carmezim, Maria J. [ICEMS Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001, Lisboa (Portugal); EST Setúbal, DEM, Instituto Politécnico de Setúbal, Campus IPS, 2910 Setúbal (Portugal); Montemor, Maria F. [ICEMS Instituto Superior Técnico, Universidade de Lisboa, Av. Rovisco Pais 1049-001, Lisboa (Portugal)

2015-03-30

Graphical abstract: - Highlights: • Functional coating of Zn with ZnO ‘Anastacia’ flowers. • Flowers are composed by nano-hexagonal units of single-crystal wurtzite ZnO. • The growth mechanism of these flowers is discussed. • Room temperature yield cost-effective electrodeposited ZnO ‘Anastacia’ flowers. - Abstract: Functional coatings composed of ZnO, a new flowered structured denominated as ‘Anastacia’ flowers, were successfully obtained through a facile and green one-step electrodeposition approach on Zn substrate. Electrodeposition was performed at constant cathodic potential, in Zn(NO{sub 3}){sub 2} aqueous solution, at pH 6 and at room temperature. The resulting ZnO thin uniform layer, with an average thickness of 300 nm, bearing top 3D hierarchical nanostructures that compose ‘Anastacia’ flowers, was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman. The results reveal a nano-architecture structure composed by nano-hexagonal units of single-crystal wurtzite ZnO structure with a [0 0 0 1] growth direction along the longitudinal particles axis. Other morphological features, sphere-like, rod-like and random distributed hexagons were also obtained by varying the electrodeposition time as observed by SEM. The Raman spectroscopy revealed the typical peak of ZnO wurtzite for all the obtained morphologies. Coatings wettability was studied and the different morphologies display distinct water contact angles with the ‘Anastacia’ flowers coating showing a wettability of 110°. These results pave the way for simple and low-cost routes for the production of novel functionalized coatings of ZnO over Zn, with potential for biomedical devices.

Nanostructured ‘Anastacia’ flowers for Zn coating by electrodepositing ZnO at room temperature

International Nuclear Information System (INIS)

Alves, Marta M.; Santos, Catarina F.; Carmezim, Maria J.; Montemor, Maria F.

2015-01-01

Graphical abstract: - Highlights: • Functional coating of Zn with ZnO ‘Anastacia’ flowers. • Flowers are composed by nano-hexagonal units of single-crystal wurtzite ZnO. • The growth mechanism of these flowers is discussed. • Room temperature yield cost-effective electrodeposited ZnO ‘Anastacia’ flowers. - Abstract: Functional coatings composed of ZnO, a new flowered structured denominated as ‘Anastacia’ flowers, were successfully obtained through a facile and green one-step electrodeposition approach on Zn substrate. Electrodeposition was performed at constant cathodic potential, in Zn(NO 3 ) 2 aqueous solution, at pH 6 and at room temperature. The resulting ZnO thin uniform layer, with an average thickness of 300 nm, bearing top 3D hierarchical nanostructures that compose ‘Anastacia’ flowers, was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Raman. The results reveal a nano-architecture structure composed by nano-hexagonal units of single-crystal wurtzite ZnO structure with a [0 0 0 1] growth direction along the longitudinal particles axis. Other morphological features, sphere-like, rod-like and random distributed hexagons were also obtained by varying the electrodeposition time as observed by SEM. The Raman spectroscopy revealed the typical peak of ZnO wurtzite for all the obtained morphologies. Coatings wettability was studied and the different morphologies display distinct water contact angles with the ‘Anastacia’ flowers coating showing a wettability of 110°. These results pave the way for simple and low-cost routes for the production of novel functionalized coatings of ZnO over Zn, with potential for biomedical devices

Electrodeposited Pt for cost-efficient and flexible dye-sensitized solar cells

International Nuclear Information System (INIS)

Kim, Seok-Soon; Nah, Yoon-Chae; Noh, Yong-Young; Jo, Jang; Kim, Dong-Yu

2006-01-01

Pt electrodes were prepared by direct and pulse current electrodeposition for use as counter electrodes in dye-sensitized solar cells. Scanning electron microscope and transmission electron microscope images confirmed the formation of uniform Pt nanoclusters of ∼40 nm composed of 3 nm nanoparticles, when the pulse current electrodeposition method was used, as opposed to the dendritic growth of Pt by the results from direct current electrodeposition. By applying pulse electrodeposited Pt which has a 1.86 times higher surface area compared to direct current electrodeposited Pt, short-circuit current and conversion efficiency were increased from 10.34 to 14.11 mA/cm 2 and from 3.68 to 5.03%, respectively. In addition, a flexible solar cell with a pulse current electrodeposited Pt counter electrode with a conversion efficiency of 0.86% was demonstrated

New silicate-germanate Cs2Pb2[(Si0.6Ge0.4)2O7] from the series A2Pb2[B2O7], A = K, Cs, B = Si, Ge with the umbrella-like [PbO3]4- group

Science.gov (United States)

Belokoneva, Elena L.; Morozov, Ivan A.; Volkov, Anatoly S.; Dimitrova, Olga V.; Stefanovich, Sergey Yu.

2018-04-01

New silicate-germanate Cs2Pb2[(Si0.6Ge0.4)2O7] was synthesized in multi-components hydrothermal solution with 20 w.% concentration of Cs2CO3 mineralizer, pH = 10. Novel mixed compound belongs to the structure type A2Pb2[B2O7] previously indicated for powders with A = K, B=Si or Ge. Singe crystal structure determination of Cs2Pb2[(Si0.6Ge0.4)2O7] revealed the need for the correction of the space group of the earlier suggested structural model from P-3 to P-3m1, as well as for the splitting of the Pb-atom position. Umbrella-like groups [PbO3]4- are located between [(Si,Ge)O4]4- tetrahedra in mica-like honeycomb layers and play the role of tetrahedra with the Pb-lone-pair as the forth apex. Crystal chemical comparison revealed similarities and differences with the classical structure type of α-celsian Ba[Al2Si2O8] with the tetrahedral double layer. Recently investigated nonlinear optical acentric borates Pb2(BO3)(NO3) and Pb2(BO3)Cl are both related to this structural type, possessing umbrella-like groups [PbO3]4- and honeycomb layers [Pb2(BO3)]+ with the BO3-triangles on the tetrahedral positions.

Performance evaluation of symmetric supercapacitor based on cobalt hydroxide [Co(OH)2] thin film electrodes

International Nuclear Information System (INIS)

Jagadale, A.D.; Kumbhar, V.S.; Dhawale, D.S.; Lokhande, C.D.

2013-01-01

In the present investigation, we have successfully assembled symmetric supercapacitor device based on cobalt hydroxide [Co(OH) 2 ] thin film electrodes using 1 M KOH as an electrolyte. Initially, potentiodynamic electrodeposition method is employed for the preparation of Co(OH) 2 thin films onto stainless steel substrate. These films are characterized for structural and morphological elucidations using X-ray diffraction (XRD) and scanning electron microscopy (SEM), respectively. The XRD reveals formation of β-Co(OH) 2 material with hexagonal crystal structure. The SEM images show formation of nanoflakes like microstructure with average flake width 100 nm. Electrochemical characterizations of Co(OH) 2 based symmetric supercapacitor cell are carried out using cyclic voltammetry, charge–discharge and electrochemical impedance spectroscopy (EIS) techniques. In the performance evaluation the maximum values of specific capacitance, specific energy and specific power are encountered as 44 F g −1 , 3.96 Wh kg −1 and 42 kW kg −1 . The value of equivalent series resistance (ESR) is estimated as 2.3 Ω using EIS

Electrodeposited Ni-B coatings: Formation and evaluation of hardness and wear resistance

International Nuclear Information System (INIS)

Krishnaveni, K.; Sankara Narayanan, T.S.N.; Seshadri, S.K.

2006-01-01

The formation of electrodeposited Ni-B alloy coatings using a dimethylamine borane (DMAB) modified Watt's nickel bath and evaluation of their structural characteristics, hardness and wear resistance are discussed. The boron content in the electrodeposited Ni-B alloy coating is determined by the ratio of rate of reduction of nickel and rate of decomposition of DMAB. The boron content of the electrodeposited Ni-B coating decreases as the current density increased from 0.4 to 4 A dm -2 . XRD diffraction pattern of electrodeposited Ni-B coatings in their as-plated condition exhibits the presence of Ni (1 1 1) (2 0 0) and (2 2 0) reflections with (1 1 1) texture. Heat treatment at 400 deg. C for 1 h has resulted in the formation of nickel boride phases, which results in an increase in hardness and wear resistance. The mechanism of wear in electrodeposited Ni-B coatings is intensive plastic deformation of the coating due to the ploughing action of the hard counter disk

Order/disorder in electrodeposited aluminum-titanium alloys

Directory of Open Access Journals (Sweden)

Stafford G.R.

2003-01-01

Full Text Available The composition, morphology, and crystallographic microstructure of Al-Ti alloys electrodeposited from two different chloroaluminate molten salt electrolytes were examined. Alloys containing up to 28 % atomic fraction Ti were electrodeposited at 150 °C from 2:1 AlCl3-NaCl with controlled additions of Ti2+. The apparent limit on alloy composition is proposed to be due to a mechanism by which Al3Ti forms through the reductive decomposition of [Ti(AlCl43]-. The composition of Al-Ti alloys electrodeposited from the AlCl3-EtMeImCl melt at 80 °C is limited by the diffusion of Ti2+ to the electrode surface. Alloys containing up to 18.4 % atomic fraction Ti are only obtainable at high Ti2+ concentrations in the melt and low current densities. Alloys electrodeposited from the higher temperature melt have an ordered L12 crystal structure while alloys of similar composition but deposited at lower temperature are disordered fcc. The appearance of antiphase boundaries in the ordered alloys suggests that the deposit may be disordered initially and then orders in the solid state, subsequent to the charge transfer step and adatom incorporation into the lattice. This is very similar to the disorder-trapping observed in rapidly solidified alloys. The measured domain size is consistent with a mechanism of diffusion-controlled doman growth at the examined deposition temperatures and times.

Engineering of Metal Microstructures; Process-Microstructure-Property Relationships for Electrodeposits

DEFF Research Database (Denmark)

Jensen, Jens Dahl

2002-01-01

and concentration of additives, current density, and mass transport. The grown films were analysed by a variety of characterisation techniques - including optical light microscopy, electron microscopy, atomic force microscopy, X-ray diffraction, thin film tensile testing, and nano-indentation. Studies of anomalous...... introduced in the deposits with the use of sodium-saccharin, which led to embrittlement of the deposits. By using ultrasonic streaming near the cathode during electrodeposition in the Watts type electrolyte, improved material distribution in machined 3-dimensional groove geometries was observed...

An Effective Electrodeposition Mode for Porous MnO2/Ni Foam Composite for Asymmetric Supercapacitors

Science.gov (United States)

Tsai, Yi-Chiun; Yang, Wein-Duo; Lee, Kuan-Ching; Huang, Chao-Ming

2016-01-01

Three kinds of MnO2/Ni foam composite electrode with hierarchical meso-macroporous structures were prepared using potentiodynamic (PD), potentiostatic (PS), and a combination of PS and PD(PS + PD) modes of electrodeposition. The electrodeposition mode markedly influenced the surface morphological, textural, and supercapacitive properties of the MnO2/Ni electrodes. The supercapacitive performance of the MnO2/Ni electrode obtained via PS + PD(PS + PD(MnO2/Ni)) was found to be superior to those of MnO2/Ni electrodes obtained via PD and PS, respectively. Moreover, an asymmetric supercapacitor device, activated carbon (AC)/PS + PD(MnO2/Ni), utilizing PS + PD(MnO2/Ni) as a positive electrode and AC as a negative electrode, was fabricated. The device exhibited an energy density of 7.7 Wh·kg−1 at a power density of 600 W·kg−1 and superior cycling stability, retaining 98% of its initial capacity after 10,000 cycles. The good supercapacitive performance and excellent stability of the AC/PS + PD(MnO2/Ni) device can be ascribed to its high surface area, hierarchical structure, and interconnected three-dimensional reticular configuration of the nickel metal support, which facilitates electrolyte ion intercalation and deintercalation at the electrode/electrolyte interface and mitigates volume change during repeated charge/discharge cycling. These results demonstrate the great potential of the combination of PS and PD modes for MnO2 electrodeposition for the development of high-performance electrodes for supercapacitors. PMID:28773371

Nanostructured tungsten trioxide thin films synthesized for photoelectrocatalytic water oxidation: a review.

Science.gov (United States)

Zhu, Tao; Chong, Meng Nan; Chan, Eng Seng

2014-11-01

The recent developments of nanostructured WO3 thin films synthesized through the electrochemical route of electrochemical anodization and cathodic electrodeposition for the application in photoelectrochemical (PEC) water splitting are reviewed. The key fundamental reaction mechanisms of electrochemical anodization and cathodic electrodeposition methods for synthesizing nanostructured WO3 thin films are explained. In addition, the effects of metal oxide precursors, electrode substrates, applied potentials and current densities, and annealing temperatures on size, composition, and thickness of the electrochemically synthesized nanostructured WO3 thin films are elucidated in detail. Finally, a summary is given for the general evaluation practices used to calculate the energy conversion efficiency of nanostructured WO3 thin films and a recommendation is provided to standardize the presentation of research results in the field to allow for easy comparison of reported PEC efficiencies in the near future. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Improvement in the Sensitivity of PbO Doped Tin Oxide Thick Film Gas Sensor by RF and Microwave Oxygen Plasma Treatment

Directory of Open Access Journals (Sweden)

J. K. SRIVASTAVA

2010-07-01

Full Text Available In the present work efforts have been made to analyze the effect of oxygen plasma and PbO doping on the sensitivity of SnO2-based thick film gas sensor for methanol, propanol and acetone. The effect of substrate temperature on the response of dual frequency (RF and microwave plasma treated thick film sensor array has also been studied. To achieve this, three sensor arrays (each with four tin oxide sensors doped with different (1 %, 2 %, 3 % and 4 % PbO concentrations were fabricated by thick film technology and then treated with oxygen plasma for various durations (5 min, 10 min. and 15 min.. The plasma treated sensors were found to possess appreciably high sensitivity at room temperature in comparison to untreated sensor. The sensitivity showed the increasing trend with plasma exposure time and 15 minutes exposure time was found to be most suitable as the sensitivity of the plasma treated sensors for this duration were high towards all the chosen vapors with maximum (97 % value for propanol. The sensitivity of the sensors were found to be increasing gradually as PbO concentration was varied from 1- 4%.

Semitransparent ZnO/poly(3,4-ethylenedioxythiophene) based hybrid inorganic/organic heterojunction thin film diodes prepared by combined radio-frequency magnetron-sputtering and electrodeposition techniques

International Nuclear Information System (INIS)

Rodríguez-Moreno, Jorge; Navarrete-Astorga, Elena; Martín, Francisco; Schrebler, Ricardo; Ramos-Barrado, José R.; Dalchiele, Enrique A.

2012-01-01

n-ZnO/p-poly(3,4-ethylenedioxythiophene) (PEDOT) semitransparent inorganic–organic hybrid vertical heterojunction thin film diodes have been fabricated with PEDOT and ZnO thin films grown by electrodeposition and radio-frequency magnetron-sputtering respectively, onto a tin doped indium oxide coated glass substrate. The diode exhibited an optical transmission of ∼ 40% to ∼ 50% in the visible region between 450 and 700 nm. The current–voltage (I–V) characteristics of the heterojunction show good rectifying diode characteristics, with a ratio of forward current to the reverse current as high as 35 in the range − 4 V to + 4 V. The I–V characteristic was examined in the framework of the thermionic emission model. The ideality factor and barrier height were obtained as 4.0 and 0.88 eV respectively. - Highlights: ► Semitransparent inorganic–organic heterojunction thin film diodes investigated ► n-ZnO/p-poly(3,4-ethylenedioxythipohene) used for the heterojunction ► Diodes exhibited an optical transmission of ∼ 40%–∼ 50% in the visible region ► Heterojunction current–voltage features show good rectifying diode characteristics ► A forward to reverse current ratio as high as 35 (− 4 V to + 4 V range) was attained

A Study on the Effect of Electrodeposition Parameters on the Morphology of Porous Nickel Electrodeposits

Science.gov (United States)

Sengupta, Srijan; Patra, Arghya; Jena, Sambedan; Das, Karabi; Das, Siddhartha

2018-03-01

In this study, the electrodeposition of nickel foam by dynamic hydrogen bubble-template method is optimized, and the effects of key deposition parameters (applied voltage and deposition time) and bath composition (concentration of Ni2+, pH of the bath, and roles of Cl- and SO4 2- ions) on pore size, distribution, and morphology and crystal structure are studied. Nickel deposit from 0.1 M NiCl2 bath concentration is able to produce the honeycomb-like structure with regular-sized holes. Honeycomb-like structure with cauliflower morphology is deposited at higher applied voltages of 7, 8, and 9 V; and a critical time (>3 minutes) is required for the development of the foamy structure. Compressive residual stresses are developed in the porous electrodeposits after 30 seconds of deposition time (-189.0 MPa), and the nature of the residual stress remains compressive upto 10 minutes of deposition time (-1098.6 MPa). Effect of pH is more pronounced in a chloride bath compared with a sulfate bath. The increasing nature of pore size in nickel electrodeposits plated from a chloride bath (varying from 21 to 48 μm), and the constant pore size (in the range of 22 to 24 μm) in deposits plated from a sulfate bath, can be ascribed to the striking difference in the magnitude of the corresponding current-time profiles.

Electrodeposition of flake-like Cu_2O on vertically aligned two-dimensional TiO_2 nanosheet array films for enhanced photoelectrochemical properties

International Nuclear Information System (INIS)

Yang, Lei; Zhang, Miao; Zhu, Kerong; Lv, Jianguo; He, Gang; Sun, Zhaoqi

2017-01-01

Highlights: • Flake-like Cu_2O/TNS with exposed {001} facets constructed p-n heterostructure. • The TNS arrays were used as starting substrates for Cu_2O growth. • The Cu_2O/TNS prepared at −0.4 V exhibits the best photoelectrochemical property. - Abstract: A novel Cu_2O/TNS composite structure of single crystal TiO_2 nanosheet (TNS) arrays decorated with flake-like Cu_2O were synthesized by a facile hydrothermal reaction followed by the electrodeposition process. The effects of deposition potential on the microstructure, morphology, and optical property of the thin films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis spectrophotometer. When the deposition potential is higher than −0.4 V, peaks corresponding to Cu appear, meanwhile, flake-like Cu_2O become agglomerating, and transform into dense Cu_2O particles. Additionally, photoelectrochemical experiments indicate that the films deposited at −0.4 V show the lowest resistivity and highest exciton separation efficiency. This enhanced photoelectrochemical properties can be explained by synergistic effect of p-type flake-like Cu_2O and n-type TiO_2 heterojunctions combined with two-dimensional TiO_2 nanosheet with exposed highly reactive {001} facets.

Fabricating Copper Nanotubes by Electrodeposition

Science.gov (United States)

Yang, E. H.; Ramsey, Christopher; Bae, Youngsam; Choi, Daniel

2009-01-01

Copper tubes having diameters between about 100 and about 200 nm have been fabricated by electrodeposition of copper into the pores of alumina nanopore membranes. Copper nanotubes are under consideration as alternatives to copper nanorods and nanowires for applications involving thermal and/or electrical contacts, wherein the greater specific areas of nanotubes could afford lower effective thermal and/or electrical resistivities. Heretofore, copper nanorods and nanowires have been fabricated by a combination of electrodeposition and a conventional expensive lithographic process. The present electrodeposition-based process for fabricating copper nanotubes costs less and enables production of copper nanotubes at greater rate.

Electrocatalysis of the hydrogen evolution reaction by rhenium oxides electrodeposited by pulsed-current

International Nuclear Information System (INIS)

Vargas-Uscategui, Alejandro; Mosquera, Edgar; Chornik, Boris; Cifuentes, Luis

2015-01-01

Highlights: • Rhenium oxides were produced by means of pulsed current electrodeposition over ITO. • The electrocatalytic behavior of rhenium oxides electrodeposited over ITO was studied. • Electrodeposited rhenium oxides showed electrocatalytic behavior increasing the rate of the hydrogen evolution reaction. • The electrocatalysis behavior was explained considering the relative abundance of Re species on the surface of the electrodeposited material. - Abstract: Rhenium oxides are materials of interest for applications in the catalysis of reactions such as those occurring in fuel cells and photoelectrochemical cells. This research work was devoted to the production of rhenium oxide by means of pulsed current electrodeposition for the electrocatalysis of the hydrogen evolution reaction (HER). Rhenium oxides were electrodeposited over a transparent conductive oxide substrate (Indium Tin-doped Oxide – ITO) in an alkaline aqueous electrolyte. The electrodeposition process allowed the production of rhenium oxides islands (200–600 nm) with the presence of three oxidized rhenium species: Re"I"V associated to ReO_2, Re"V"I associated to ReO_3 and Re"V"I"I associated to H(ReO_4)H_2O. Electrodeposited rhenium oxides showed electrocatalytic behavior over the HER and an increase of one order of magnitude of the exchange current density was observed compared to the reaction taking place on the bare substrate. The electrocatalytic behavior varied with the morphology and relative abundance of oxidized rhenium species in the electrodeposits. Finally, two mechanisms of electrocatalysis were proposed to explain experimental results.

Electrodeposition of ZnO nano-wires lattices with a controlled morphology; Electrodepot de reseaux de nanofils de ZnO a morphologie controlee

Energy Technology Data Exchange (ETDEWEB)

Elias, J.; Tena-Zaera, R.; Katty, A.; Levy-Clement, C. [Centre National de la Recherche Scientifique (CNRS), Lab. de Chimie Metallurgique des Terres Rares, UPR 209, 94 - Thiais (France)

2006-07-01

In this work, it is shown that the electrodeposition is a changeable low cost method which allows, according to the synthesis conditions, to obtain not only plane thin layers of ZnO but different nano-structures too. In a first part, are presented the formation conditions of a compact thin layer of nanocrystalline ZnO electrodeposited on a conducing glass substrate. This layer plays a buffer layer role for the deposition of a lattice of ZnO nano-wires. The step of nano-wires nucleation is not only determined by the electrochemical parameters but by the properties of the buffer layer too as the grain sizes and its thickness. In this context, the use of an electrodeposition method in two steps allows to control the nano-wires length and diameter and their density. The morphology and the structural and optical properties of these nano-structures have been analyzed by different techniques as the scanning and transmission electron microscopy, the X-ray diffraction and the optical spectroscopy. These studies show that ZnO nano-structures are formed of monocrystalline ZnO nano-wires, presenting a great developed surface and a great optical transparency in the visible. These properties make ZnO a good material for the development of nano-structured photovoltaic cells as the extremely thin absorber cells (PV ETA) or those with dye (DSSC) which are generally prepared with porous polycrystalline TiO{sub 2}. Its replacement by a lattice of monocrystalline ZnO nano-wires allows to reduce considerably the number of grain boundaries and in consequence to improve the transport of the electrons. The results are then promising for the PV ETA cells with ZnO nano-wires. (O.M.)

Templated electrodeposition of functional nanostructures: nanowires, nanotubes and nanocubes

OpenAIRE

Maijenburg, A.W.

2014-01-01

This thesis is entitled “Templated electrodeposition of functional nanostructures: nanowires, nanotubes and nanocubes”. Templated electrodeposition is the synthesis technique that was used throughout this thesis, and it comprises the use of a template with specific shape and dimensions for the formation of different types of nanostructures. Throughout this thesis, three different nanostructures were made: nanowires (Chapters 2 to 6), nanotubes (Chapters 2 and 5) and nanocubes (Chapters 7 and ...

A statistical approach for optimizing parameters for electrodeposition of indium (III) sulfide (In2S3) films, potential low-hazard buffer layers for photovoltaic applications

Science.gov (United States)

Mughal, Maqsood Ali

Clean and environmentally friendly technologies are centralizing industry focus towards obtaining long term solutions to many large-scale problems such as energy demand, pollution, and environmental safety. Thin film solar cell (TFSC) technology has emerged as an impressive photovoltaic (PV) technology to create clean energy from fast production lines with capabilities to reduce material usage and energy required to manufacture large area panels, hence, lowering the costs. Today, cost ($/kWh) and toxicity are the primary challenges for all PV technologies. In that respect, electrodeposited indium sulfide (In2S3) films are proposed as an alternate to hazardous cadmium sulfide (CdS) films, commonly used as buffer layers in solar cells. This dissertation focuses upon the optimization of electrodeposition parameters to synthesize In2S3 films of PV quality. The work describe herein has the potential to reduce the hazardous impact of cadmium (Cd) upon the environment, while reducing the manufacturing cost of TFSCs through efficient utilization of materials. Optimization was performed through use of a statistical approach to study the effect of varying electrodeposition parameters upon the properties of the films. A robust design method referred-to as the "Taguchi Method" helped in engineering the properties of the films, and improved the PV characteristics including optical bandgap, absorption coefficient, stoichiometry, morphology, crystalline structure, thickness, etc. Current density (also a function of deposition voltage) had the most significant impact upon the stoichiometry and morphology of In2S3 films, whereas, deposition temperature and composition of the solution had the least significant impact. The dissertation discusses the film growth mechanism and provides understanding of the regions of low quality (for example, cracks) in films. In2S3 films were systematically and quantitatively investigated by varying electrodeposition parameters including bath

Development of Electrodeposited CIGS Solar Cells: Cooperative Research and Development Final Report, CRADA Number CRD-09-357

Energy Technology Data Exchange (ETDEWEB)

Neale, Nathan [National Renewable Energy Lab. (NREL), Golden, CO (United States)

2016-09-01

At present, most PV materials are fabricated by vacuum technologies. Some of the many disadvantages of vacuum technology are complicated instrumentation, material waste, high cost of deposition per surface area, and instability of some compounds at the deposition temperature. Solution-based approaches for thin-film deposition on large areas are particularly desirable because of the low capital cost of the deposition equipment, relative simplicity of the processes, ease of doping, uniform deposition on a variety of substrates (including interior and exterior of tubes and various nonplanar devices), and potential compatibility with high-throughput (e.g., roll-to-roll) processing. Of the nonsilicon solar photovoltaic device modules that have been deployed to date, those based on the n-CdS/p-CdTe is a leading candidate. Two features in the optical characteristics of CdTe absorber are particularly attractive for photovoltaic conversion of sunlight; (a) its energy bandgap of 1.5 eV, which provides an optimal match with the solar spectrum and thus facilitates its efficient utilization and (b) the direct mode of the main optical transition which results in a large absorption coefficient and turn permits the use of thin layer (1-2 um) of active material. Thin films of CdTe required for these devices have been fabricated by a variety of methods (e.g., vapor transport deposition, vacuum deposition, screen printing and close-spaced sublimation). Electrodeposition is another candidate deserves more attention. This project will focus on delivering low-cost, high efficiency electrodeposited CdTe-based device.

Electrodeposition of gold nanoparticles on mesoporous TiO{sub 2} photoelectrode to enhance visible region photocurrent

Energy Technology Data Exchange (ETDEWEB)

Supriyono,; Krisnandi, Yuni Krisyuningsih; Gunlazuardi, Jarnuzi, E-mail: jarnuzi@ui.ac.id [Department of Chemistry, FMIPA, Universitas Indonesia, Kampus UI Depok (Indonesia)

2016-04-19

Electrodeposition of gold nanoparticles (Au NPs) on the mesoporous TiO{sub 2} photoelectrode to enchance visible region photocurrent have been investigated. Mesoporous TiO{sub 2} was prepared by a sol gel method and immobilized to the fluorine doped tin oxide (FTO) substrate by dip coating technique. Gold nanoparticles were electrodeposited on the TiO{sub 2} surface and the result FTO/TiO{sub 2}/Au was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive spectroscopy (EDS), UV-Vis diffuse reflectance spectroscopy (DRS), and X-ray diffraction (XRD). The generated photocurrent was evaluated with an electrochemical workstation (e-DAQ/e-recorder 401) using 60 W wolfram lamp as visible light source. The photoelectrochemical evaluation indicated that the presence of gold nanoparticles on TiO{sub 2} photoelectrode shall enhance the photocurrent up to 50%.

Preparation of Cu{sub 2}ZnSnS{sub 4} thin films by sulfurization of co-electroplated Cu-Zn-Sn precursors

Energy Technology Data Exchange (ETDEWEB)

Araki, Hideaki; Kubo, Yuki; Jimbo, Kazuo; Maw, Win Shwe; Katagiri, Hironori; Yamazaki, Makoto; Oishi, Koichiro; Takeuchi, Akiko [Nagaoka National College of Technology, 888 Nishikatakai, Nagaoka, Niigata 940-8532 (Japan)

2009-05-15

Cu{sub 2}ZnSnS{sub 4} (CZTS) thin films were prepared by sulfurization of electrodeposited Cu-Zn-Sn precursors. The Cu-Zn-Sn precursors were deposited on Mo-coated glass substrates in a one-step process from an electrolyte containing copper (II) sulfate pentahydrate, zinc sulfate heptahydrate, tin (II) chloride dehydrate and tri-sodium citrate dehydrate. The precursors were sulfurized by annealing with sulfur at temperatures of 580 C and 600 C in an N{sub 2} atmosphere. X-ray diffraction peaks attributable to CZTS were detected in the sulfurized films. Photovoltaic cells with the structure glass/Mo/CZTS/ CdS/ZnO:Al/Al were fabricated using the CZTS films by sulfurizing the electrodeposited precursors. The best photovoltaic cell performance was obtained with Zn-rich samples. An open-circuit voltage of 540 mV, a short-circuit current of 12.6 mA/cm{sup 2} and an efficiency of 3.16% were achieved. (copyright 2009 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

Study of CdTe and HgCdTe thin films obtained by electrochemical methods

International Nuclear Information System (INIS)

Guillen, C.

1990-01-01

Cadmium telluride polycrystalline thin films were fabricated on SnO 2 -coated glass substrates by potentiostatic electrodeposition and characterized by X-ray diffraction, energy dispersive X-ray analyses (EDAX), optical and electrical measurements. The films dseposited at potentials more positive than -0.65 V vs.SCE were p-type but those deposited at more negative potentials were n-type. All CdTe thin films showed a band-gap energy about 1.45 eV and a large absorption coeffici-ent (a=10 5 cm -1 ) above de band edge. The addition of even small amounts of mercury to the CdTe produces higuer conductivity values and lower band-gap energies. We have prepared HgCdTe thin films where the band-gap energies ranged between 0.93 and 0.88 eV depending on the ratio of mercury to cadmium. Heat treatment at 300 0 C increases the crystalline diameter and alter the composition of the electrodeposited films, a decrease of the resistivity values was also observed. (Author)

Electrodeposition of enzymes-integrated mesoporous composite films by interfacial templating: A paradigm for electrochemical biosensors

International Nuclear Information System (INIS)

Wang, Dongming; Tan, Yiwei

2014-01-01

The development of nanostructured electrodes for electrochemical biosensors is of significant interest for modern detection, portable devices, and enhanced performance. However, development of such sensors still remains challenging due to the time-consuming, detriment-to-nature, and costly modifications of both electrodes and enzymes. In this work, we report a simple one-step approach to fabricating high-performance, direct electron transfer (DET) based nanoporous enzyme-embedded electrodes by electrodeposition coupled with recent progress in potential-controlled interfacial surfactant assemblies. In contrast to those previously electrodeposited mesoporous materials that are not bioactive, we imparted the biofunctionality to electrodeposited mesoporous thin films by means of the amphiphilic phospholipid templates strongly interacting with enzymes. Thus, phospholipid-templated mesoporous ZnO films covalently inlaid with the pristine enzymes were prepared by simple one-step electrodeposition. We further demonstrate two examples of such hybrid film electrodes embedded with alcohol dehydrogenase (ADH) and glucose oxidase (GOx), which are effectively employed as electrochemical biosensors for amperometric sensing of ethanol and glucose without using any electron relays. The favorable mass transport and large contact surface area provided by nanopores play an important role in improving the performance of these two biosensors, such as excellent sensitivities, low detection limits, and fast response. The matrix mesoporous films acting as effective electronic bridges are responsible for DET between enzyme molecules and metal electrode

Synthesis of MnO2-graphene composites with enhanced supercapacitive performance via pulse electrodeposition under supergravity field

International Nuclear Information System (INIS)

Liu, Tingting; Shao, Guangjie; Ji, Mingtong; Wang, Guiling

2014-01-01

A method of pulse electrodeposition under supergravity field was proposed to synthesize MnO 2 -graphene composites. Supergravity is very efficient for promoting mass transfer and decreasing concentration polarization during the electrodeposition process. The synthesis was conducted on our homemade supergravity equipment. The strength of supergravity field depended on the rotating speed of the ring electrode. 3D flower like MnO 2 spheres composed of nanoflakes were acquired when the rotating speed was 3000 rpm. Graphene nanosheets play as a role of conductive substrates for MnO 2 growing. The composites are evaluated as electrode materials for supercapacitors. Electrochemical results show that the maximum specific capacitance of the MnO 2 -graphene composite is 595.7 F g −1 at a current density of 0.5 A g −1 . In addition, the composite exhibits excellent cycle stability with no capacitance attenuation after 1000 cycles. The approach provides new ideas for developing supercapacitor electrode materials with high performance. - Graphical abstract: 3D flower like MnO 2 spheres composed of nanoflakes were acquired at 3000 rpm. - Highlights: • MnO 2 -graphene composites were prepared by pulse electrodeposition under supergravity. • 3D flower like MnO 2 spheres are anchored on the graphene nanosheets. • The MnO 2 -graphene electrode exhibits a specific capacitance of 595.7 F g −1

Investigations on the electrodeposition behaviors of Bi0.5Sb1.5Te3 thin film from nitric acid baths

International Nuclear Information System (INIS)

Li Feihui; Huang Qinghua; Wang Wei

2009-01-01

The electrochemical reduction process of Bi 3+ , HTeO 2 + , Sb III and their mixtures in nitric acid medium was investigated by means of cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS) measurements. The reduction products electrodeposited at various potentials were examined using X-ray diffraction (XRD) and energy dispersive spectroscopy (EDS). The results show that cathodic process in the nitric acid solution containing Bi 3+ , HTeO 2 + and Sb III involves the following reduction reactions in different polarizing potential ranges: In low polarizing potential ranges, Te 0 is formed firstly on the electrode surface through the electrochemical reduction of HTeO 2 + ; with the negative shift of the cathodic polarizing potential, the reduction reaction of Bi 3+ with Te 0 to form Bi 2 Te 3 takes place; when the cathodic polarizing potential is negative enough, Bi 3+ and Sb III react with Te 0 to form Bi 0.5 Sb 1.5 Te 3 . The results indicate that Bi 0.5 Sb 1.5 Te 3 films can be fabricated by controlling the electrodepositing potential in a proper high potential ranges.

Electrodeposition of engineering alloy coatings

DEFF Research Database (Denmark)

Christoffersen, Lasse

Nickel based electrodeposited alloys were investigated with respect to their deposition process, heat treatment, hardness, corrosion resistance and combined wear-corrosion resistance. The investigated alloys were Ni-B, Ni-P and Ni-W, which are not fully developed for industrial utilisation...... are written in brackets). Temperature and especially pH influenced the cathodic efficiency of the electrodeposition processes for Ni-W and Ni-P. Mass balance problems of the development alloy processes are identified.Heat treatment for one hour at approx. 350°C, 400°C and 600°C of electrodeposited Ni-B, Ni......-P and Ni-W, respectively, resulted in hardness values of approx. 1000 HV0.1 in the case of Ni-P(6), approx. 1100 HV0.1 in the case of Ni-W(40-53) and approx. 1300 HV0.1 in the case of Ni-B(5). Cracks, which emerged during electrodeposition and heat treatment, were observed on Ni-W and Ni-B.The corrosion...

Utilization of electrodeposition for electrothermal atomic absorption spectrometry determination of gold

International Nuclear Information System (INIS)

Konecna, Marie; Komarek, Josef

2007-01-01

Gold was determined by electrothermal atomic absorption spectrometry after electrochemical preconcentration on the graphite ridge probe used as a working electrode and sample support. The probe surface was electrochemically modified with Pd, Re and the mixture of both. The electrolysis of gold was performed under galvanostatic control at 0.5 mA. Maximum pyrolysis temperature for the probe surface modified with Pd was 1200 deg. C, with Re 1300 deg. C. The relative standard deviation for the determination of 2 μg l -1 Au was not higher than 5.6% (n = 8) for 2 min electrodeposition. The sensitivity of gold determination was reproducible for 300 electrodeposition and atomization cycles. When the probe surface was modified with a mixture of Pd and Re the detection limit was 31 ng l -1 for 2 min electrodeposition, 3.7 ng l -1 for 30 min, 1.5 ng l -1 for 1 h and 0.4 ng l -1 for 4 h electrodeposition, respectively. The procedure was applied to the determination of gold in river water samples. The relative standard deviation for the determination of 2.5 ng l -1 Au at 4 h electrodeposition time at 0.5 mA was 7.5%

Preparation and characterization of electrodeposited CuInSe{sub 2} thin films; Preparation et caracterisation des couches minces de CuInSe{sub 2} electrodeposees

Energy Technology Data Exchange (ETDEWEB)

Fahoume, M.; Chraibi, F.; Ennaoui, A. [Universite Mohammed 5, Rabat (Morocco). Faculte des Sciences; Fahoume, M.; Aggour, M. [Universite Ibn Tofail, Faculte des Sciences, Kenitra (Morocco)

1998-01-01

CuInSe{sub 2} is one of the most promising materials for use in photoelectrochemical as well in photovoltaic solar cells because of its excellent photoactive properties such as high optical absorption coefficient (10`4-10`5 cm`-`1) and good stability. It has been prepared from an aqueous solution containing CuCl{sub 2}, InCl{sub 3}, H{sub 2}SeO{sub 3} complexed by citrate (Na{sub 3}C{sub 6}H{sub 5}O{sub 7}). The kinetics of electrodeposition has been studied by using the rotating disk electrode method (RDE). X-ray diffraction showed the formation of CuInSe{sub 2} films, of chalcopyrite structure, at potentials ranged between -0.95 V and - 1.12 V (vs. SSE). The composition of the deposited films has been studied by energy dispersive analysis of X-rays (EDAX) and Rutherford backscattering spectroscopy (RBS). From the results, it has been found that stoichiometric chalcopyrite CuInSe{sub 2} has been obtained by controlling both composition, deposition potential, solution temperature and pH. (authors) 16 refs.

Evaluation of H{sub 2}O{sub 2}-generation during oxygen reduction at electrodeposited Pt particles on mask scratched electrodes

Energy Technology Data Exchange (ETDEWEB)

Kishi, Akira; Inoue, Mitsuhiro; Umeda, Minoru, E-mail: mumeda@vos.nagaokaut.ac.jp

2013-08-15

In this study, the Pt particle deposition was systematically performed by our proposed mask scratch and subsequent Pt electrodeposition in order to investigate the H{sub 2}O{sub 2}-byproduct generation efficiency during O{sub 2} reduction. By peeling a part of polymer layer coated on a glassy carbon substrate using an atomic force microscope cantilever, scratched areas are regularly made. The Pt particles are deposited only on the above-mentioned scratched areas, indicating that the controlled Pt deposition has been achieved. The background cyclic voltammetry of the prepared electrodes showed that the deposited nanoparticles are certainly composed of Pt. Moreover, the electrochemical surface area of the deposited Pt (Pt-ESA) linearly increases with the increasing scratched area, revealing that the Pt-ESAs can be controlled by the mask scratch-based Pt electrodeposition method. It should be noted that an increase in the Pt-ESA not only increases the O{sub 2} reduction currents, but also enhances the H{sub 2}O{sub 2} generation efficiency.

Chirality of magneto-electrodeposited metal film electrodes

International Nuclear Information System (INIS)

Mogi, Iwao; Watanabe, Kazuo

2008-01-01

The chiral electrode behaviors of magneto-electrodeposited (MED) Ag and Cu films were examined for the electrochemical reactions of D-glucose, L-glucose and L-cysteine. The Ag and Cu films were electrodeposited under a magnetic field of 2 T parallel (+2 T) or antiparallel (-2 T) to the faradaic current. For MED films of both Ag and Cu, the oxidation current of L-glucose was larger than that of D-glucose on the +2 T-film electrodes, and the results were opposite on the - 2 T-film electrodes. These facts demonstrate that the MED metal films possess the ability of chiral recognition for D- and L-glucoses. The MED Ag film electrodes also exhibited chiral behavior for the oxidation of L-cysteine

Acidic aqueous uranium electrodeposition for target fabrication

International Nuclear Information System (INIS)

Saliba-Silva, A.M.; Oliveira, E.T.; Garcia, R.H.L.; Durazzo, M.

2013-01-01

Direct irradiation of targets inside nuclear research or multiple purpose reactors is a common route to produce 99 Mo- 99m Tc radioisotopes. The electroplating of low enriched uranium over nickel substrate might be a potential alternative to produce targets of 235 U. The electrochemistry of uranium at low temperature might be beneficial for an alternative route to produce 99 Mo irradiation LEU targets. Electrodeposition of uranium can be made using ionic and aqueous solutions producing uranium oxide deposits. The performance of uranium electrodeposition is relatively low because a big competition with H 2 evolution happens inside the window of electrochemical reduction potential. This work explores possibilities of electroplating uranium as UO 2 2+ (Uranium-VI) in order to achieve electroplating uranium in a sufficient amount to be commercially irradiated in the future Brazilian RMB reactor. Electroplated nickel substrate was followed by cathodic current electrodeposition from aqueous UO 2 (NO 3 ) 2 solution. EIS tests and modeling showed that a film formed differently in the three tested cathodic potentials. At the lower level, (-1.8V) there was an indication of a double film formation, one overlaying the other with ionic mass diffusion impaired at the interface with nickel substrate as showed by the relatively lower admittance of Warburg component. (author)

Preparation and characterization of electrodeposited cobalt nanowires

International Nuclear Information System (INIS)

Irshad, M. I.; Mohamed, N. M.; Ahmad, F.; Abdullah, M. Z.

2014-01-01

Electrochemical deposition technique has been used to deposit cobalt nanowires into the nano sized channels of Anodized Aluminium Oxide (AAO) templates. CoCl 2 Ðœ‡6H2O salt solution was used, which was buffered with H 3 BO 3 and acidified by dilute H 2 SO 4 to increase the plating life and control pH of the solution. Thin film of copper around 150 nm thick on one side of AAO template coated by e-beam evaporation system served as cathode to create electrical contact. FESEM analysis shows that the as-deposited nanowires are highly aligned, parallel to one another and have high aspect ratio with a reasonably high pore-filing factor. The TEM results show that electrodeposited cobalt nanowires are crystalline in nature. The Hysteresis loop shows the magnetization properties for in and out of plane configuration. The in plane saturation magnetization (Ms) is lower than out of plane configuration because of the easy axis of magnetization is perpendicular to nanowire axis. These magnetic nanowires could be utilized for applications such as spintronic devices, high density magnetic storage, and magnetic sensor applications

Preparation and characterization of electrodeposited cobalt nanowires

Energy Technology Data Exchange (ETDEWEB)

Irshad, M. I., E-mail: imrancssp@gmail.com; Mohamed, N. M., E-mail: noranimuti-mohamed@petronas.com.my [Department of Fundamental and Applied Sciences, Universiti Teknologi PETRONAS, 31750 PERAK (Malaysia); Ahmad, F., E-mail: faizahmad@petronas.com.my; Abdullah, M. Z., E-mail: zaki-abdullah@petronas.com.my [Department of Mechanical Engineering, Universiti Teknologi PETRONAS, 31750 PERAK (Malaysia)

2014-10-24

Electrochemical deposition technique has been used to deposit cobalt nanowires into the nano sized channels of Anodized Aluminium Oxide (AAO) templates. CoCl{sub 2}Ðœ‡6H2O salt solution was used, which was buffered with H{sub 3}BO{sub 3} and acidified by dilute H{sub 2}SO{sub 4} to increase the plating life and control pH of the solution. Thin film of copper around 150 nm thick on one side of AAO template coated by e-beam evaporation system served as cathode to create electrical contact. FESEM analysis shows that the as-deposited nanowires are highly aligned, parallel to one another and have high aspect ratio with a reasonably high pore-filing factor. The TEM results show that electrodeposited cobalt nanowires are crystalline in nature. The Hysteresis loop shows the magnetization properties for in and out of plane configuration. The in plane saturation magnetization (Ms) is lower than out of plane configuration because of the easy axis of magnetization is perpendicular to nanowire axis. These magnetic nanowires could be utilized for applications such as spintronic devices, high density magnetic storage, and magnetic sensor applications.

Study of broadband near-infrared emission in Tm3+-Er3+ codoped TeO2-WO3-PbO glasses.

Science.gov (United States)

Balda, R; Fernández, J; Fernández-Navarro, J M

2009-05-25

In this work, we report the near-infrared emission properties of Tm(3+)-Er(3+) codoped tellurite TeO(2)-WO(3)-PbO glasses under 794 nm excitation. A broad emission from 1350 to 1750 nm corresponding to the Tm(3+) and Er(3+) emissions is observed. The full width at half-maximum of this broadband increases with increasing [Tm]/[Er] concentration ratio up to a value of ~ 160 nm. The energy transfer between Tm(3+) and Er(3+) ions is evidenced by both the temporal behavior of the near-infrared luminescence and the effect of Tm3+ codoping on the visible upconversion of Er(3+) ions.

The mechanism of cathodic electrodeposition of epoxy coatings and the corrosion behaviour of the electrodeposited

Directory of Open Access Journals (Sweden)

VESNA B. MISKOVIC-STANKOVIC

2002-05-01

Full Text Available The model of organic film growth on a cathode during electrodeposition process proposes the current density-time and film thickness-time relationships and enables the evaluation of the rate contants for the electrochemical reaction of OH– ion evolution and for the chemical reaction of organic film deposition. The dependences of film thickness and rate constants on the applied voltage, bath temperature and resin concentration in the electrodeposition bath have also been obtained. The deposition parameters have a great effect on the cathodic electrodeposition process and on the protective properties of the obtained electrodeposited coatings. From the time dependences of the pore resistance, coating capacitance and relative permittivity, obtained from impedance measurements, the effect of applied voltage, bath temperature and resin concentration on the protective properties of electrodeposited coatings has been shown. Using electrochemical impedance spectroscopy, thermogravimetric analysis, gravimetric liquid sorption experiments, differential scanning calorimetry and optical miscroscopy, the corrosion stability of epoxy coatings was investigated. A mechanism for the penetration of electrolyte through an organic coating has been suggested and the shape and dimensions of the conducting macropores have been determined. It was shown that conduction through a coating depends only on the conduction through the macropores, although the quantity of electrolyte in the micropores of the polymer net is about one order of magnitude greater than that inside the conducting macropores.

Preparation of Gd2O3 Ultrafine Nanoparticles by Pulse Electrodeposition Followed by Heat-treatment Method

Directory of Open Access Journals (Sweden)

Mustafa Aghazadeh

2016-12-01

Full Text Available Gd2O3 nanoparticles were prepared by a two–step process; cathodic electrodeposition followed by heat-treatment method. First, Gd(OH3 nanoparticles was galvanostatically deposited from nitrate bath on the steel substrate by pulse current (PC mode. The deposition experiments was conducted at a typical on-time and off-time (ton=1ms and toff=1ms for 60 min. The electrodeposited precursor was then heat-treated at 600 oC for 3h to obtain oxide product (i.e. Gd2O3. The morphological and structural analyses confirmed that the gadolinium hydroxynitrate nanoparticles with composition of [Gd(OH2.5(NO30.5 yH2O] and uniform size about 10 nm have been prepared during pulse cathodic electrodeposition process. Furthermore, mechanism of the gadolinium hydroxynitrate nanoparticles was explained based on the base (OH– electrogeneration process on the cathode surface. The morphological observations by SEM and TEM, and structural analyses via XRD and FT-IR revealed that the oxide product is composed of well-dispersed Gd2O3 nanoparticles with pure cubic crystalline structure. It was observed that the calcination process has no effect on the morphology of the Gd2O3 nanoparticles. Mechanism of oxide formation during heat-treatment step was investigated by DSC-TG analysis and discussed in detail. The results of this work showed that pulse current deposition followed by heat–treatment can be recognized as an easy and facile method for preparation of the Gd2O3 fine nanoparticles.

Electrochemical corrosion measurements on noble electrodeposits

DEFF Research Database (Denmark)

Christoffersen, Lasse; Maahn, Ernst Emanuel

1998-01-01

Novel electrodeposits are compared with hard chrome and electroless Ni-P with respect to production, corrosion resistance and hardness.......Novel electrodeposits are compared with hard chrome and electroless Ni-P with respect to production, corrosion resistance and hardness....

Electrodeposition of a Au-Dy2O3 Composite Solid Oxide Fuel Cell Catalyst from Eutectic Urea/Choline Chloride Ionic Liquid

Directory of Open Access Journals (Sweden)

Claudio Mele

2012-12-01

Full Text Available  In this research we have fabricated and tested Au/Dy2O3 composites for applications as Solid Oxide Fuel Cell (SOFC electrocatalysts. The material was obtained by a process involving electrodeposition of a Au-Dy alloy from a urea/choline chloride ionic liquid electrolyte, followed by selective oxidation of Dy to Dy2O3 in air at high temperature. The electrochemical kinetics of the electrodeposition bath were studied by cyclic voltammetry, whence optimal electrodeposition conditions were identified. The heat-treated material was characterised from the morphological (scanning electron microscopy, compositional (X-ray fluorescence spectroscopy and structural (X-ray diffractometry points of view. The electrocatalytic activity towards H2 oxidation and O2 reduction was tested at 650 °C by electrochemical impedance spectrometry. Our composite electrodes exhibit an anodic activity that compares favourably with the only literature result available at the time of this writing for Dy2O3 and an even better cathodic performance.

Semitransparent ZnO/poly(3,4-ethylenedioxythiophene) based hybrid inorganic/organic heterojunction thin film diodes prepared by combined radio-frequency magnetron-sputtering and electrodeposition techniques

Energy Technology Data Exchange (ETDEWEB)

Rodriguez-Moreno, Jorge; Navarrete-Astorga, Elena; Martin, Francisco [Laboratorio de Materiales y Superficies (Unidad Asociada al CSIC), Departamentos de Fisica Aplicada and Ing. Quimica, Universidad de Malaga, E29071 Malaga (Spain); Schrebler, Ricardo [Instituto de Quimica, Facultad de Ciencias, Pontificia Universidad Catolica de Valparaiso, Casilla 4059, Valparaiso (Chile); Ramos-Barrado, Jose R. [Laboratorio de Materiales y Superficies (Unidad Asociada al CSIC), Departamentos de Fisica Aplicada and Ing. Quimica, Universidad de Malaga, E29071 Malaga (Spain); Dalchiele, Enrique A., E-mail: dalchiel@fing.edu.uy [Instituto de Fisica, Facultad de Ingenieria, Herrera y Reissig 565, C.C. 30, 11000 Montevideo (Uruguay)

2012-12-15

n-ZnO/p-poly(3,4-ethylenedioxythiophene) (PEDOT) semitransparent inorganic-organic hybrid vertical heterojunction thin film diodes have been fabricated with PEDOT and ZnO thin films grown by electrodeposition and radio-frequency magnetron-sputtering respectively, onto a tin doped indium oxide coated glass substrate. The diode exhibited an optical transmission of {approx} 40% to {approx} 50% in the visible region between 450 and 700 nm. The current-voltage (I-V) characteristics of the heterojunction show good rectifying diode characteristics, with a ratio of forward current to the reverse current as high as 35 in the range - 4 V to + 4 V. The I-V characteristic was examined in the framework of the thermionic emission model. The ideality factor and barrier height were obtained as 4.0 and 0.88 eV respectively. - Highlights: Black-Right-Pointing-Pointer Semitransparent inorganic-organic heterojunction thin film diodes investigated Black-Right-Pointing-Pointer n-ZnO/p-poly(3,4-ethylenedioxythipohene) used for the heterojunction Black-Right-Pointing-Pointer Diodes exhibited an optical transmission of {approx} 40%-{approx} 50% in the visible region Black-Right-Pointing-Pointer Heterojunction current-voltage features show good rectifying diode characteristics Black-Right-Pointing-Pointer A forward to reverse current ratio as high as 35 (- 4 V to + 4 V range) was attained.

Preparation and characterization of chalcopyrite compound for thin film solar cells

Directory of Open Access Journals (Sweden)

Sh. Ebrahim

2011-03-01

Full Text Available CulnS2 thin films were electrodeposited onto indium tin oxide substrate by the electrodeposition technique. Cyclic voltammetry and chronoamperometry were carried out to determine the optimum pH and the amount of sodium thiosulfate for electroplating CuInS2 compound. The composition, crystallinity and optical properties of the compounds synthesized were studied by energy dispersive X-ray (EDX, (SEM, X-ray diffraction and UV–Visible spectra. It was found that the increasing pH shifts the electrodepositions voltage toward more negative and lowers the deposition current. Increasing the amount of sodium thiosulfate also decreases the deposition current but it has no effect on the deposition potential. It was concluded that CuInS2 with atomic stoichiometric ratio was prepared at pH equals 1 and 150 ml of 0.1 M sodium thiosulfate, 5 ml of 0.1 M indium chloride and 5 ml of 0.1 M cupper acetate. The energy gaps were calculated to be 1.6, 1.7 and 1.75 eV for CuInS2 prepared at 1, 1.5 and 2 of pH, respectively. It was indicated that the amount of the sodium thiosulfate has a slight effect on the energy gap.

Characterization of Pb(Zr, Ti)O3 thin films fabricated by plasma enhanced chemical vapor deposition on Ir-based electrodes

International Nuclear Information System (INIS)

Lee, Hee-Chul; Lee, Won-Jong

2002-01-01

Structural and electrical characteristics of Pb(Zr, Ti)O 3 (PZT) ferroelectric thin films deposited on various Ir-based electrodes (Ir, IrO 2 , and Pt/IrO 2 ) using electron cyclotron resonance plasma enhanced chemical vapor deposition were investigated. On the Ir electrode, stoichiometric PZT films with pure perovskite phase could be obtained over a very wide range of processing conditions. However, PZT films prepared on the IrO 2 electrode contain a large amount of PbO x phases and exhibited high Pb-excess composition. The deposition characteristics were dependent on the behavior of PbO molecules on the electrode surface. The PZT thin film capacitors prepared on the Ir bottom electrode showed different electrical properties depending on top electrode materials. The PZT capacitors with Ir, IrO 2 , and Pt top electrodes showed good leakage current characteristics, whereas those with the Ru top electrode showed a very high leakage current density. The PZT capacitor exhibited the best fatigue endurance with an IrO 2 top electrode. An Ir top electrode provided better fatigue endurance than a Pt top electrode. The PZT capacitor with an Ir-based electrode is thought to be attractive for the application to ferroelectric random access memory devices because of its wide processing window for a high-quality ferroelectric film and good polarization, fatigue, and leakage current characteristics

Apparatus for eliminating electrodeposition of radioactive nuclide

International Nuclear Information System (INIS)

Inomata, Ichiro; Ishibe, Tadao; Matsunaga, Masaaki; Konuki, Ryoichi; Suzuki, Kazunori; Watanabe, Minoru; Tomoshige, Shozo; Kondo, Kozo.

1990-01-01

In a conventional device for eliminating by radioactive nuclides electrodeposition, a liquid containing radioactive nuclides is electrolyzed under a presence of non-radioactive heavy metals and removing radioactive nuclides by electrodepositing them together with the heavy metals. Two anode plates are opposed in an electrolysis vessel of this device. A plurality (4 to 6) of cathode plates are arranged between the anodes in parallel with them and the cathode surfaces opposed to the anodes are insulated. Further, such a plurality of cathode plates are grouped into respective units. Alternatively, the anode plate is made of platinum-plated titanium material and the cathode plate is made of stainless steel. In the thus constituted electrodeposition eliminating device, since the cathode surface directed to the anodes on both ends are insulated, all of electric current from the anode reach the core cathode after flowing around the cathodes at both ends. As a result, there is no substantial difference in the flowing length of the electrolyzing current to each of the cathodes and these is neither difference in the electrodeposition amount. The electrodeposited products are adhered uniformly and densely to the electrodes and, simultaneously, Co-60 and Mn-54, etc. are also electrodeposited. (I.S.)

Theory and practice of metal electrodeposition

CERN Document Server

Gamburg, Yuliy D

2011-01-01

fills the gap between modern developments in electrochemistry and outdated information on metals electrodeposition currently available in competing titles essential information on the theoretical and practical electrochemistry necessary to investigate modern metal deposition is provided part of the growing literature on electrodeposition

Alloy formation during chromium electrodeposition at niobium cathode in molten salts

International Nuclear Information System (INIS)

Kuznetsov, S.A.; Glagolevskaya, A.L.

1993-01-01

Alloy formation during electrodeposition of chromium at niobium cathode is studied in salt melts. It is shown that during chromium electrodeposition at niobium support intermetallic compound Cr 2 Nb is formed. Thermodynamic characteristics of Cr 0.66 Nb 0.33 alloy are determined. 10 refs., 1 fig

Lead dioxide electrodes for high potential anodic processes

Directory of Open Access Journals (Sweden)

A. B. VELICHENKO

2001-12-01

Full Text Available Doping of PbO2 by cations (Fe3+, Co2+ and Ni2+, by F- and by cations and F- simultaneously is discussed as a way of improving the stability and electrochemical activity in processes occurring at high potentials. Doping allows the control of the amount of structural water in an oxide. Radiotracer experiments showed that high electrodeposition current densities favour the segregation of incorporated tritium (protons at the surface. On the other hand, fluorine doping results in a marked decrease in the amount of surface oxygen species. The influence of doping with metal cations strongly depends on the nature of the metal. Iron behaves like fluorine, while nickel causes an accumulation of surface oxygen species. Doped PbO2 electrodes have quite good activities for the electrogeneration of ozone. In particular, Fe and Co doped PbO2 showed a current efficiency of 15–20 % for this process. This result is relevant to our recent studies on “cathodic oxidation”, i.e., an ozone mediated electrochemical method in which an O2 stream is used to sweep the O2/O3 gas mixture produced at a PbO2 anode into the cathodic compartment of the same electrochemical cell containing polluting species.

Synthesis of Co3O4 nanosheets via electrodeposition followed by ozone treatment and their application to high-performance supercapacitors

Science.gov (United States)

Kung, Chung-Wei; Chen, Hsin-Wei; Lin, Chia-Yu; Vittal, R.; Ho, Kuo-Chuan

2012-09-01

A thin film of Co3O4 nanosheets is electrodeposited on a flexible Ti substrate by a one-step potentiostatic method, followed by an UV-ozone treatment for 30 min. The films before and after the UV-ozone treatment are characterized with X-ray diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The film is composed of Co(OH)2 before UV-ozone treatment, and of Co3O4 after the treatment. The morphologies of both films are examined by scanning electron microscopy (SEM) and transmission electron microscope (TEM). The obtained films are composed of nanosheets, and there is no change in their sheet-like morphology before and after the UV-ozone treatment. When applied for a supercapacitor, the Co3O4 modified Ti electrode (Co3O4/Ti) shows a far higher capacitance than that of the Co(OH)2 modified Ti electrode. The electrodeposition time and NaOH concentration in the electrolyte are optimized. A remarkably high specific capacitance of 1033.3 F g-1 is obtained for the Co3O4 thin film at a charge-discharge current density of 2.5 A g-1. The long-term stability data shows that there is still 77% of specific capacitance remaining after 3000 repeated charge-discharge cycles. The high specific capacitance and long-term stability suggest the potential use of Co3O4/Ti for making a flexible supercapacitor.

Electrodeposition of Al-Mn alloy on AZ31B magnesium alloy in molten salts

International Nuclear Information System (INIS)

Zhang Jifu; Yan Chuanwei; Wang Fuhui

2009-01-01

The Al-Mn alloy coatings were electrodeposited on AZ31B Mg alloy in AlCl 3 -NaCl-KCl-MnCl 2 molten salts at 170 deg. C aiming to improve the corrosion resistance. However, in order to prevent AZ31B Mg alloy from corrosion during electrodeposition in molten salts and to ensure excellent adhesion of coatings to the substrate, AZ31B Mg alloy should be pre-plated with a thin zinc layer as intermediate layer. Then the microstructure, composition and phase constituents of the coatings were investigated by scanning electron microscopy (SEM), energy-dispersive X-ray spectrometry (EDX), and X-ray diffraction (XRD). It was indicated that, by adjusting the MnCl 2 content in the molten salts from 0.5 wt% to 2 wt%, the Mn content in the alloy coating was increased and the phase constituents were changed from f.c.c Al-Mn solid solution to amorphous phase. The corrosion resistance of the coatings was evaluated by potentiodynamic polarization measurements in 3.5% NaCl solution. It was confirmed that the Al-Mn alloy coatings exhibited good corrosion resistance with a chear passive region and significantly reduced corrosion current density at anodic potentiodynamic polarization. The corrosion resistance of the alloy coatings was also related with the microstructure and Mn content of the coatings.

Electrochemical preparation and characterization of n-CdSe sub 0. 65 Te sub 0. 35 polycrystalline thin films: Influence of annealing

Energy Technology Data Exchange (ETDEWEB)

Gutierrez, M T; Ortega, J [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain). Inst. de Energias Renovables

1989-12-01

CdSe{sub 0.65}Te{sub 0.35} thin films have been prepared by electrodeposition. The films were characterized by X-ray diffraction, optical and photoelectrochemical methods. The influence of annealing treatments on the physical parameters (grain size, d, donor concentration, N{sub D}, and hole diffusion length, L{sub P}) determining the photoelectrochemical behaviour of electrodeposited CdSe{sub 0.65}Te{sub 0.35} thin films in contact with sulfide/polysulfide electrolytes have been systematically studied. (orig.).

Template-assisted electrodeposition of Ni and Ni/Au nanowires on planar and curved substrates

Science.gov (United States)

Guiliani, Jason; Cadena, John; Monton, Carlos

2018-02-01

We present a variant of the template-assisted electrodeposition method that enables the synthesis of large arrays of nanowires (NWs) on flat and curved substrates. This method uses ultra-thin (50 nm-10 μm) anodic aluminum oxide membranes as a template. We have developed a procedure that uses a two-polymer protective layer to transfer these templates onto almost any surface. We have applied this technique to the fabrication of large arrays of Ni and segmented composition Ni/Au NWs on silicon wafers, Cu tapes, and thin (0.2 mm) Cu wires. In all cases, a complete coverage with NWs is achieved. The magnetic properties of these samples show an accentuated in-plane anisotropy which is affected by the form of the substrate (flat or curve) and the length of the NWs. Unlike current lithography techniques, the fabrication method proposed here allows the integration of complex nanostructures into devices, which can be fabricated on unconventional surfaces.

Effect of methanol ratio in mixed solvents on optical properties and wettability of ZnO films by cathodic electrodeposition

International Nuclear Information System (INIS)

Zhang, Miao; Xu, Kai; Jiang, Xishun; Yang, Lei; He, Gang; Song, Xueping; Sun, Zhaoqi; Lv, Jianguo

2014-01-01

Highlights: • Different surface morphologies of ZnO films were prepared by cathodic electrodeposition. • The surface morphologies are controlled through add different ratio methanol to electrolyte. • The morphology changes from nanorods with hexagonal structure to net-like nanostructure. • The wettability of films shows obvious change with increasing methanol ratio. • The maximum light-induced CA change has been observed with the methanol ratio of 0.8. - Abstract: ZnO thin films were prepared in the electrolyte with different methanol ratio by cathodic electrodeposition method. Microstructure, surface morphology, optical properties and wettability of the thin films were investigated by X-ray diffractometer, field-emission scanning electron microscope, ultraviolet–visible spectroscope, fluorescence spectrometer and water contact angle apparatus. Increase of methanol ratio in the solvents may restrain the (0 0 2) plane preferential orientation in some extent. Change of current density curves with the ratio of methanol in the solution play a vital role on electrochemical reaction kinetics, microstructure and/or surface morphology of ZnO thin films. With the methanol ratio increase from 0 to 0.8, the surface morphology changes from nanorods to net-like nanostructure. The adsorbed NO 3 − ions on the polar planes hinder the crystal growth along the c-axis and redirect the growth direction along the nonpolar planes. The maximum and minimum band gaps have been obtained in the ZnO thin films with the methanol ratio of 0.4 and 0.6, respectively. Change of contact angle before UV irradiation may be related to surface morphology and oxygen vacancies. The maximum light-induced water contact angle change has been observed in the sample with the methanol ratio of 0.8. The results may be attributed to the higher surface roughness and net-like morphology

Effect of methanol ratio in mixed solvents on optical properties and wettability of ZnO films by cathodic electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Zhang, Miao; Xu, Kai; Jiang, Xishun; Yang, Lei; He, Gang; Song, Xueping [School of Physics and Material Science, Anhui University, Hefei 230601 (China); Sun, Zhaoqi, E-mail: szq@ahu.edu.cn [School of Physics and Material Science, Anhui University, Hefei 230601 (China); Lv, Jianguo, E-mail: lvjg1@163.com [School of Electronic and Information Engineering, Hefei Normal University, Hefei 230601 (China)

2014-12-05

Highlights: • Different surface morphologies of ZnO films were prepared by cathodic electrodeposition. • The surface morphologies are controlled through add different ratio methanol to electrolyte. • The morphology changes from nanorods with hexagonal structure to net-like nanostructure. • The wettability of films shows obvious change with increasing methanol ratio. • The maximum light-induced CA change has been observed with the methanol ratio of 0.8. - Abstract: ZnO thin films were prepared in the electrolyte with different methanol ratio by cathodic electrodeposition method. Microstructure, surface morphology, optical properties and wettability of the thin films were investigated by X-ray diffractometer, field-emission scanning electron microscope, ultraviolet–visible spectroscope, fluorescence spectrometer and water contact angle apparatus. Increase of methanol ratio in the solvents may restrain the (0 0 2) plane preferential orientation in some extent. Change of current density curves with the ratio of methanol in the solution play a vital role on electrochemical reaction kinetics, microstructure and/or surface morphology of ZnO thin films. With the methanol ratio increase from 0 to 0.8, the surface morphology changes from nanorods to net-like nanostructure. The adsorbed NO{sub 3}{sup −} ions on the polar planes hinder the crystal growth along the c-axis and redirect the growth direction along the nonpolar planes. The maximum and minimum band gaps have been obtained in the ZnO thin films with the methanol ratio of 0.4 and 0.6, respectively. Change of contact angle before UV irradiation may be related to surface morphology and oxygen vacancies. The maximum light-induced water contact angle change has been observed in the sample with the methanol ratio of 0.8. The results may be attributed to the higher surface roughness and net-like morphology.

Deuterium retention in molten salt electrodeposition tungsten coatings

International Nuclear Information System (INIS)

Zhou, Hai-Shan; Xu, Yu-Ping; Sun, Ning-Bo; Zhang, Ying-Chun; Oya, Yasuhisa; Zhao, Ming-Zhong; Mao, Hong-Min; Ding, Fang; Liu, Feng; Luo, Guang-Nan

2016-01-01

Highlights: • We investigate D retention in electrodeposition W coatings. • W coatings are exposed to D plasmas in the EAST tokamak. • A cathodic current density dependence on D retention is found. • Electrodeposition W exhibits lower D retention than VPS-W. - Abstract: Molten salt electrodeposition is a promising technology to manufacture the first wall of a fusion reactor. Deuterium (D) retention behavior in molten salt electrodeposition tungsten (W) coatings has been investigated by D-plasma exposure in the EAST tokamak and D-ion implantation in an ion beam facility. Tokamak exposure experiments demonstrate that coatings prepared with lower current density exhibit less D retention and milder surface damage. Deuterium-ion implantation experiments indicate the D retention in the molten salt electrodeposition W is less than that in vacuum plasma spraying W and polycrystalline W.

Deuterium retention in molten salt electrodeposition tungsten coatings

Energy Technology Data Exchange (ETDEWEB)

Zhou, Hai-Shan [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Xu, Yu-Ping [Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Sun, Ning-Bo; Zhang, Ying-Chun [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing (China); Oya, Yasuhisa [Radioscience Research Laboratory, Faculty of Science, Shizuoka University, Shizuoka (Japan); Zhao, Ming-Zhong [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Mao, Hong-Min [Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Ding, Fang; Liu, Feng [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Luo, Guang-Nan, E-mail: gnluo@ipp.ac.cn [Institute of Plasma Physics, Chinese Academy of Sciences, Hefei (China); Science Island Branch of Graduate School, University of Science and Technology of China, Hefei (China); Hefei Center for Physical Science and Technology, Hefei (China); Hefei Science Center of Chinese Academy of Science, Hefei (China)

2016-12-15

Highlights: • We investigate D retention in electrodeposition W coatings. • W coatings are exposed to D plasmas in the EAST tokamak. • A cathodic current density dependence on D retention is found. • Electrodeposition W exhibits lower D retention than VPS-W. - Abstract: Molten salt electrodeposition is a promising technology to manufacture the first wall of a fusion reactor. Deuterium (D) retention behavior in molten salt electrodeposition tungsten (W) coatings has been investigated by D-plasma exposure in the EAST tokamak and D-ion implantation in an ion beam facility. Tokamak exposure experiments demonstrate that coatings prepared with lower current density exhibit less D retention and milder surface damage. Deuterium-ion implantation experiments indicate the D retention in the molten salt electrodeposition W is less than that in vacuum plasma spraying W and polycrystalline W.

Synthesis of ZnTe nanowires onto TiO2 nanotubular arrays by pulse-reverse electrodeposition

International Nuclear Information System (INIS)

Gandhi, T.; Raja, K.S.; Misra, M.

2009-01-01

Growth of ZnTe nanowires using a pulse-reverse electrodeposition technique from a non-aqueous solution is reported. ZnTe nanowires were grown on to an ordered nanotubular TiO 2 template in a propylene carbonate solution at 130 o C inside a controlled atmosphere glove box. The pulse-reverse electro deposition process consisted of a cathodic pulse at - 0.62 V and an anodic pulse at 0.75 V Vs Zn 2+ /Zn. Stoichiometry growth of crystalline ZnTe nanowires was observed in the as-deposited condition. The anodic pulse cycle of the pulse-reverse electrodeposition process presumably introduced zinc vacancies as deep level acceptors at an energy level of E v + 0.47 eV. The resultant ZnTe nanowires showed p-type semiconductivity with a resistivity of 7.8 x 10 4 Ω cm and a charge carrier density of 1.67 x 10 14 cm -3 . Annihilation of the defects occurred upon thermal annealing that resulted in marginal decrease in the defect density.

Effect of Surface Roughness and Structure Features on Tribological Properties of Electrodeposited Nanocrystalline Ni and Ni/Al2O3 Coatings

Science.gov (United States)

Góral, Anna; Lityńska-Dobrzyńska, Lidia; Kot, Marcin

2017-05-01

Metal matrix composite coatings obtained by electrodeposition are one of the ways of improving the surfaces of materials to enhance their durability and properties required in different applications. This paper presents an analysis of the surface topography, microstructure and properties (residual stresses, microhardness, wear resistance) of Ni/Al2O3 nanocomposite coatings electrodeposited on steel substrates from modified Watt's-type baths containing various concentrations of Al2O3 nanoparticles and a saccharin additive. The residual stresses measured in the Ni/Al2O3 coatings decreased with an increasing amount of the co-deposited ceramics. It was established that the addition of Al2O3 powder significantly improved the coatings' microhardness. The wear mechanism changed from adhesive-abrasive to abrasive with a rising amount of Al2O3 particles and coating microhardness. Nanocomposite coatings also exhibited a lower coefficient of friction than that of a pure Ni-electrodeposited coating. The friction was found to depend on the surface roughness, and the smoother surfaces gave lower friction coefficients.

2008 Gordon Research Conference on Electrodeposition [Conference summary report

Energy Technology Data Exchange (ETDEWEB)

Moffat, Thomas P.; Gray, Nancy Ryan

2009-01-01

Electrodeposition melds key aspects of electrochemistry and materials science. In the last decade the advent of a variety of remarkable in situ characterization methods combined with the ever expanding application of wet chemical processing in high end technological endeavors has transformed the nature of the field. The 'old black magic' is giving way to the rigors of science as the electrodeposition process plays a central role in the fabrication of state-of-the-art ULSI and MEMS devices as well as being a key tool in the fabrication of novel materials and nanostructures. This year the conference will consider several timely issues such as how electrodeposition can contribute to the effective production of energy conversion devices, ranging from solar collectors to fuel cell electrocatalysts. Likewise, the challenge of building contacts and interconnects for next generation electronics will be examined over length scales ranging from individual atoms or molecules to chip stacking. Electrochemical fabrication of magnetic materials and devices as well as composite materials will also be discussed. Nucleation and growth phenomena underlie all aspect of electrochemical deposition and this year's meeting will consider the effect of both adsorbates and stress state on morphological evolution during thin film growth. A variety of new measurement methods for studying the growing electrode/electrolyte interface will also be detailed. In addition to the scheduled talks a session of short talks on late breaking news will be held Wednesday evening. There will also be at least two lively poster sessions that are essential elements of the conference and to which all attendees are encouraged to contribute. This will be 7th Electrodeposition GRC and based on past experience it is the premier 'mixing bowl' where young investigators and international experts have an extended opportunity to interact in a fun and collegial atmosphere. The afternoons provide

Influence of atmospheric pressure plasma treatment on surface properties of PBO fiber

International Nuclear Information System (INIS)

Zhang Ruiyun; Pan Xianlin; Jiang Muwen; Peng Shujing; Qiu Yiping

2012-01-01

Highlights: ► PBO fibers were treated with atmospheric pressure plasmas. ► When 1% of oxygen was added to the plasma, IFSS increased 130%. ► Increased moisture regain could enhance plasma treatment effect on improving IFSS with long treatment time. - Abstract: In order to improve the interfacial adhesion property between PBO fiber and epoxy, the surface modification effects of PBO fiber treated by atmospheric pressure plasma jet (APPJ) in different time, atmosphere and moisture regain (MR) were investigated. The fiber surface morphology, functional groups, surface wettability for control and plasma treated samples were analyzed by scanning electron microscope (SEM), X-ray photoelectron spectroscopy (XPS) and water contact angle measurements, respectively. Meanwhile, the fiber interfacial shear strength (IFSS), representing adhesion property in epoxy, was tested using micro-bond pull-out test, and single fiber tensile strength was also tested to evaluate the mechanical performance loss of fibers caused by plasma treatment. The results indicated that the fiber surface was etched during the plasma treatments, the fiber surface wettability and the IFSS between fiber and epoxy had much improvement due to the increasing of surface energy after plasma treatment, the contact angle decreased with the treatment time increasing, and the IFSS was improved by about 130%. The processing atmosphere could influence IFSS significantly, and moisture regains (MR) of fibers also played a positive role on improving IFSS but not so markedly. XPS analysis showed that the oxygen content on fiber surface increased after treatment, and C=O, O-C=O groups were introduced on fiber surface. On the other hand, the observed loss of fiber tensile strength caused by plasma treatment was not so remarkable to affect the overall performance of composite materials.

Structural defects in electrodeposited Ni studied by positron annihilation

International Nuclear Information System (INIS)

Vertes, A.; Szeles, C.; Czako-Nagy, I.; Lakatos-Varsanyi, M.

1982-01-01

Structural investigation of electrodeposited Ni was carried out by positron annihilation (PA) technique. Additional Moessbauer effect and X-ray diffraction measurements were also performed. The samples were produced under different plating conditions resulting in stress in the range -100 to +600 N/mm 2 . From the positron lifetime measurements it seems that the defect pattern of electrodeposited Ni samples might be substantially different from sample to sample with different deposition and plating conditions. (Auth.)

Electrodeposition of Zn-Co and Zn-Co-Fe alloys from acidic chloride electrolytes

NARCIS (Netherlands)

Lodhi, Z.F.; Mol, J.M.C.; Hovestad, A.; Terryn, H.; Wit, J.H.W. de

2007-01-01

The electrodeposition operating conditions for Zn-Co and Zn-Co-Fe alloys from chloride baths were studied. The electrodeposition was performed on a high strength steel substrate, under galvanostatic conditions, for a range of current densities at varying Co2+ and Fe2+ bath concentrations and at

Electrodeposition and Thermoelectric Properties of Cu-Se Binary Compound Films

Science.gov (United States)

Yang, Mengqian; Shen, Zhengwu; Liu, Xiaoqing; Wang, Wei

2016-03-01

Cu-Se binary compound films have been prepared by electrodeposition from solutions containing CuSO4, H2SeO3, and H2SO4 and their composition, structure, and thermoelectric performance analyzed. Moving the depositing potential negatively increased the Cu content in the film, remarkably so for relatively low Cu2+ concentration in the solution. X-ray diffraction analysis showed that the phase composition of the films varied with their Cu content. Cu-Se binary compound films electrodeposited from solutions with different concentration ratios of CuSO4 to H2SeO3 showed two different phases: α-Cu2- x Se (monoclinic) with Se content in the range of 33.3 at.% to 33.8 at.%, and β-Cu2Se (cubic) with Se content in the range of 35.3 at.% to 36.0 at.%. The highest power factor for electrodeposited Cu2- x Se film was 0.13 mW/(K2 m) with Seebeck coefficient of 56.0 μV/K.

Preparation and characterization of a PbO protective glass; Elaboration et caracterisation d un verre protecteur a base de PbO

Energy Technology Data Exchange (ETDEWEB)

Ayadi, Azzedine; Stiti, Nacera; Benaissa, Abdelazeze [Laboratoire des materiaux mineraux et composites, Faculte des sciences de l ingenieur - Universite de Boumerdes - 35000 Boumerdes - (Algeria); Palou, Martin [Departement ceramique et verre, Faculte de chimie, Universite de Bratislava - (Slovakia)

2006-07-01

The study of the binary system of lead silicate glass PbO-SiO{sub 2}, and particularly the glasses having more than 80% of PbO and no alkaline oxides allows to answer to some preoccupations and requirements towards these glasses, in particular their transparencies and their attenuation power, on account of the high values of the refractive index and the density of these glasses. Radiation protection is a field which concerns all the countries of the world including Algeria; this country is then concerned by the import of this product used in hospitals for instance. On account of the importance of this glass and of its wide application domain, it is interesting to study it in order to be able to manufacture it in Algeria and to improve its properties. The aim of this work is then to prepare different lead silicate glasses allowing a maximal absorption of the ionizing radiations. (O.M.)

Electrodeposition of Fe_3O_4 layer from solution of Fe_2(SO_4)_3 with addition ethylene glycol

International Nuclear Information System (INIS)

Dahlan, Dahyunir; Asrar, Allan

2016-01-01

The electrodeposition of Fe_3O_4 layer from the solution Fe_2(SO_4)_3 with the addition of ethylene glycol on Indium Tin Oxide (ITO) substrate has been performed. The electrodeposition was carried out using a voltage of 5 volts for 120 seconds, with and without the addition of 2% wt ethylene glycol. Significant effects of temperature on the resulting the samples is observed when they are heated at 400 °C. Structural characterization using X-ray diffraction (XRD) shows that all samples produce a layer of Fe_3O_4 with particle size less than 50 nanometers. The addition of ethylene glycol and the heating of the sample causes a shrinkage in particle size. The scanning electron microscopy (SEM) characterization shows that Fe_3O_4 layer resulting from the process of electrodeposition of Fe_2(SO_4)_3 without ethylene glycol, independent of whether the sample is heated or not, is uneven and buildup. Layer produced by the addition of ethylene glycol without heating produces spherical particles. On contrary, when the layer is heated the spherical particles transform to irregularly-shaped particles with smaller size.

Fabrication, characterization and electrocatalytic application of a lead dioxide electrode with porous titanium substrate

International Nuclear Information System (INIS)

Zhang, Wenli; Kong, Haishen; Lin, Haibo; Lu, Haiyan; Huang, Weimin; Yin, Jian; Lin, Zheqi; Bao, Jinpeng

2015-01-01

In this study, PbO 2 electrode was prepared on porous Ti/SnO 2 –Sb 2 O 5 substrate (denoted as 3D-Ti/PbO 2 electrode), and its electrochemical properties were investigated in detail. The electrodeposition mechanism of 3D-Ti/PbO 2 electrode was investigated by cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Scanning electron microscope (SEM) result showed that the 3D-Ti/PbO 2 electrode possessed porous structure when it was electrodeposited for time less than 30 min. The 3D-Ti/PbO 2 electrode prepared for 10 min had more active sites than the lead dioxide electrode electrodeposited on planar titanium substrate (denoted as 2D-Ti/PbO 2 electrode) and its electrochemical porosity is about 54%. The embedded structure between porous Ti/SnO 2 –Sb 2 O 5 substrate and PbO 2 coating increased the stability of 3D-Ti/PbO 2 electrode. The service life of 3D-Ti/PbO 2 electrode was about 350 h which was much longer than 2D-Ti/PbO 2 electrode. What's more, 3D-Ti/PbO 2 electrode had better electrocatalytic activity towards phenol degradation than 2D-Ti/PbO 2 electrode. - Highlights: • 3D-Ti/PbO 2 electrode was prepared on a porous titanium substrate. • The electrochemical active surface area was investigated. • The activity of 3D-Ti/PbO 2 electrode towards phenol oxidation was investigated. • 3D-Ti/PbO 2 electrode shows superior electrocatalytic activity.

Electrodepositing of Au on hollow PS micro-spheres

International Nuclear Information System (INIS)

Sun Jingyuan; Zhang Yunwang; Du Kai; Wan Xiaobo; Xiao Jiang; Zhang Wei; Zhang Lin; Chen Jing

2010-01-01

Using the self-regulating new micro-sphere electrodepositing device, the techniques of electrodepositing gold on hollow PS micro-spheres were established. The experiment was carried out under the following conditions: voltage was about 0.7 ∼ 0.8 V, current density was 2.0 mA · cm -2 , the temperature was 45 degree C, cathode rotating rate was 250 r · min -1 , flow rate of the solution was 7 mL · min -1 · cm -2 . Hollow gold-plated micro-spheres were prepared with well spherical symmetry, uniform thickness and surface smoothness under 500 nm. The speed of the gold depositing was 6 μm · h -1 . (authors)

Interfacial electronic structure of electrodeposited Ag nanoparticles on iron oxide nanorice particles

Energy Technology Data Exchange (ETDEWEB)

Sohn, Young Ku [Dept. of Chemistry, Yeungnam University, Gyeongsan (Korea, Republic of)

2016-12-15

A bimetallic hybrid nanostructure of uni- formly electrodeposited Ag NPs on an Fe oxide nanorice particle template was developed. Figure 6 schematically illustrates uniform electrodeposition of Ag NPs on Fe oxide nanorice supported on a Si substrate. According to Ar + ion depth-probling XPS spectra, the electrodeposited Ag NPs are metallic, and the Fe oxide nanorice particles consist of a metallic shell covered by ultrathin FeOOH or Fe 2 O 3 shells. When the template was functionalized with 1,4-diisocyanobenzene, one terminal NC group was bridge- bonded as in the N C form on the Fe surface. The newly developed selective facial electrodeposition method will be very useful for facial fabrication of bimetallic hybrid systems for diverse application areas.

High-performance flexible electrode based on electrodeposition of polypyrrole/MnO2 on carbon cloth for supercapacitors

Science.gov (United States)

Fan, Xingye; Wang, Xiaolei; Li, Ge; Yu, Aiping; Chen, Zhongwei

2016-09-01

A highly flexible electrodes based on electrodeposited MnO2 and polypyrrole composite on carbon cloth is designed and developed by a facile in-situ electrodeposition technique. Such flexible composite electrodes with multiply layered structure possess a high specific capacitance of 325 F g-1 at a current density of 0.2 A g-1, and an excellent rate capability with a capacitance retention of 70% at a high current density of 5.0 A g-1. The superior electrochemical performance is mainly due to the unique electrode with improved ion- and electron-transportation pathways as well as the efficient utilization of active materials and electrode robustness. The excellent electrochemical performance and the low cost property endow this flexible nanocomposite electrode with great promise in applications of flexible supercapacitors.

PbTe mechanosynthesis from PbO and Te

International Nuclear Information System (INIS)

Rojas-Chavez, Hugo; Diaz-de la Torre, Sebastian; Jaramillo-Vigueras, David; Plascencia, Gabriel

2009-01-01

Experimental results concerning the mechanosynthesis (MSY), of PbTe from the PbO-Te powder system, at room temperature an atmospheric conditions are reported. XRD results for samples milled for and after 5.4 ks only show PbTe diffraction peaks; neither Te nor PbO or any other solid phase were detected. Particle size and morphology, was followed by SEM observations. Phase evolution and quantification was monitored by Rietveld refinements of the X-ray diffraction data. It was found that the use of lead oxide as a component of the mechanosynthesis system reduces milling time with respect to the Pb-Te metallic system with mechanical alloying.

Cationic electrodepositable coating composition comprising lignin

Science.gov (United States)

Fenn, David; Bowman, Mark P; Zawacky, Steven R; Van Buskirk, Ellor J; Kamarchik, Peter

2013-07-30

A cationic electrodepositable coating composition is disclosed. The present invention in directed to a cationic electrodepositable coating composition comprising a lignin-containing cationic salt resin, that comprises (A) the reaction product of: lignin, an amine, and a carbonyl compound; (B) the reaction product of lignin, epichlorohydrin, and an amine; or (C) combinations thereof.

Removal of Cd 2+ ion from diluted aqueous solutions by electrodeposition on reticulated vitreous carbon electrodes

Directory of Open Access Journals (Sweden)

Tramontina Jucelânia

2002-01-01

Full Text Available The electrodeposition of Cd2+ ion was investigated in pH 4.8 sulfuric-sulfate solutions in the presence of dissolved O2. In potentiostatic conditions, using reticulated vitreous carbon (RVC electrodes of 30, 60 and 100 pores per inch (ppi, high removal efficiency values were achieved in the potential range from --0.90 to --1.10 V for solutions containing 5 and 10 mg L-1 of Cd2+ ion. In this potential range, Cd electrodeposition is a mass transport controlled reaction and the concentration of the metallic ion decays exponentially with time following a pseudo-first order kinetics. For the 30 ppi RVC, the current efficiency and removal efficiency values found were, respectively, 45 % and 96 % for a solution containing 10 mg L-1 of Cd2+ ion after 30 minutes electrolysis at --0.90 V while 33 % and 99% were found for the 60 ppi RVC. The concentration decay of Cd2+ ion in the solution was monitored after each experiment by anodic stripping voltammetry at a hanging mercury drop electrode.

Nanostructured zinc oxide photoelectrodes by green routes M-SILAR and electrodeposition for dye sensitized solar cell

Science.gov (United States)

Gaikwad, M. A.; Suryawanshi, M. P.; Maldar, P. S.; Dongale, T. D.; Moholkar, A. V.

2018-04-01

Surfactant-free, ultrasound assisted modified successive ionic layer adsorption and reaction (M-SILAR) method and home-made microcontroller based low-cost potentiostat system are employed to prepare zinc oxide (ZnO) nanostructure based thin films. The comparison between physicochemical as well as photoelectrochemical (PEC) properties of the nanostructures prepared via two different template free, simplistic and cost-effective green routes have been discussed in detail. X-ray diffraction and Raman analysis confirm the formation of phase pure ZnO with the hexagonal crystal structure. Surface morphology significantly affects the physicochemical as well as PEC properties of ZnO thin films. Nanorods (NRs) and nanosheets (NSs) based ZnO thin films sensitized with N3 dye have been directly used as photoelectrodes in the dye-sensitized solar cell (DSSC). The power conversion efficiency (PCE) of 0.59% is achieved with Jsc of 4.04 mA/cm2 and Voc of 0.44 V for the DSSC in which the M-SILAR deposited 1-D ZnO NRs based thin film is used as the photoanode. While relatively less PCE of 0.29% with Jsc of 2.53 mA/cm2 and Voc of 0.36 V is obtained for DSSC prepared using electrodeposited 2-D ZnO NSs. In the NSs like 2-D surface morphology, the presence of multiple grain boundaries are acted as traps for the diffusing electrons, which reduces the electron mobility through it.

Analysis of the first temperate broad host range brucellaphage (BiPBO1 isolated from B. inopinata

Directory of Open Access Journals (Sweden)

Jens Andre Hammerl

2016-01-01

Full Text Available Brucella species are important human and animal pathogens. Though, only little is known about mobile genetic elements of these highly pathogenic bacteria. To date, neither plasmids nor temperate phages have been described in brucellae. We analysed genomic sequences of various reference and type strains and identified a number of putative prophages residing within the Brucella chromosomes. By induction, phage BiPBO1 was isolated from B. inopinata. BiPBO1 is a siphovirus that infects several Brucella species including B. abortus and B. melitensis. Integration of the phage genome occurs adjacent to a tRNA gene in chromosome 1 (chr 1. The bacterial (attB and phage (attP attachment sites comprise an identical sequence of 46 bp. This sequence exists in many Brucella and Ochrobactrum species. The BiPBO1 genome is composed of a 46,877 bp double-stranded DNA. Eighty-seven putative gene products were determined, of which 32 could be functionally assigned. Strongest similarities were found to a temperate phage residing in the chromosome of Ochrobactrum anthropi ATCC 49188 and to prophages identified in several families belonging to the order rhizobiales. The data suggest that horizontal gene transfer may occur between Brucella and Ochrobactrum and underpin the close relationship of these environmental and pathogenic bacteria.

Microstructure and tribological property of nanocrystalline Co–W alloy coating produced by dual-pulse electrodeposition

International Nuclear Information System (INIS)

Su Fenghua; Huang Ping

2012-01-01

Highlights: ► The nanocrystalline Co–W alloy coating were produced by dual-pulse electrodeposition from aqueous bath with cobalt sulfate and sodium tungstate. ► The correlation between the electrodeposition condition, the microstructure and alloy composition, and the hardness and tribological properties of electrodeposited Co–W alloy coatings were established. ► By careful control of the electrodeposition condition and the bath composition, the Co–W alloy coating excellent performance of microhardness and tribological properties, can exhibit excellent performances of microhardness and tribological properties. - Abstract: The nanocrystalline Co–W alloy coatings were produced by dual-pulse electrodeposition from aqueous bath with cobalt sulfate and sodium tungstate (Na 2 WO 4 ). Influence of the current density and Na 2 WO 4 concentration in bath on the microstructure, morphology and hardness of the Co–W alloy coatings were investigated using an X-ray diffraction, a scanning electronic microscope and a Vickers hardness tester, respectively. In addition, the friction and wear properties of the Co–W alloy coating electrodeposited under different condition were evaluated with a ball-on-disk UMT-3MT tribometer. The correlation between the electrodeposition condition, the microstructure and alloy composition, and the hardness and tribological properties of the deposited Co–W alloy coatings were discussed in detail. The results showed that the microhardness of the deposited Co–W alloy coating was significantly affected by its average grain size, W content and crystal orientation. Smaller grain size, higher W content and strong hcp (1 0 0) orientation favor the improvement of the hardness for Co–W alloy coatings. The deposited Co–W alloy coating could obtain the maximum microhardness over 1000 kgf mm −2 by careful control of the electrodeposition conditions. The tribological properties of the electrodeposited Co–W alloy coating were greatly

Challenges of sample preparation for cross sectional EBSD analysis of electrodeposited nickel films

DEFF Research Database (Denmark)

Alimadadi, Hossein; Pantleon, Karen

2009-01-01

Thorough microstructure and crystallographic orientation analysis of thin films by means of electron backscatter diffraction requires cross section preparation of the film-substrate compound. During careful preparation, changes of the rather non-stable as-deposited microstructure must be avoided....... Different procedures for sample preparation including mechanical grinding and polishing, electropolishing and focused ion beam milling have been applied to a nickel film electrodeposited on top of an amorphous Ni-P layer on a Cu-substrate. Reliable EBSD analysis of the whole cross section can be obtained...

Thermal and structural characterization of the vitreous samples in the SiO2 - PbO - Na2O system

Directory of Open Access Journals (Sweden)

Mocioiu Catalina Oana

2006-01-01

Full Text Available Lead-containing glasses have been used from the ancient time. Recently, due to the possible application in optics, electronics, nuclear techniques, wastes inactivation. the interest in these types of glasses has been renewed. For lead waste inactivation, glasses with high amount of PbO in the composition are required, those exhibiting at the same time a high chemical and thermal stability. Thermal behavior of lead-silicate glasses was examined by differential thermal analysis (DTA. Infrared spectroscopy was used to investigate the structure of the glasses. The spectra were interpreted in terms of the structures of silicate group by comparison with the spectra of other silicate crystals. The DTA and infrared data were correlated with the chemical stability tests.

A mechanistic study on templated electrodeposition of one-dimensional TiO2 nanorods and nanotubes using TiOSO4 as a precursor

KAUST Repository

Teo, Gladys Y.

2014-10-01

One-dimensional (1D) TiO2 nanorods and nanotubes have been successfully synthesized by templated electrodeposition within an anodic aluminium oxide membrane (AAM) using an aqueous precursor containing TiOSO 4. The deposition voltages were found to influence the resultant nanostructure of TiO2. Using a precursor of aqueous TiOSO4 at pH 3 maintained at 10 °C, TiO2 nanorods were electrodeposited in the AAM between applied voltages of - 1.4 V to - 1.0 V (vs. Ag/AgCl), while TiO2 nanotubes were obtained at less negative voltages of - 1.0 V to - 0.3 V (vs. Ag/AgCl). Cyclic voltammetry (CV) revealed that nitrate reduction in the voltage range of - 0.3 V to - 1.4 V played an essential role in the formation of TiO2. The mechanism for TiO2 nanotube formation has been elucidated, paving the way for the future tailoring of metal oxide nanostructures by templated electrodeposition. © 2014 Elsevier B.V.

A mechanistic study on templated electrodeposition of one-dimensional TiO2 nanorods and nanotubes using TiOSO4 as a precursor

KAUST Repository

Teo, Gladys Y.; Ryan, Mary P.; Riley, D. Jason

2014-01-01

One-dimensional (1D) TiO2 nanorods and nanotubes have been successfully synthesized by templated electrodeposition within an anodic aluminium oxide membrane (AAM) using an aqueous precursor containing TiOSO 4. The deposition voltages were found to influence the resultant nanostructure of TiO2. Using a precursor of aqueous TiOSO4 at pH 3 maintained at 10 °C, TiO2 nanorods were electrodeposited in the AAM between applied voltages of - 1.4 V to - 1.0 V (vs. Ag/AgCl), while TiO2 nanotubes were obtained at less negative voltages of - 1.0 V to - 0.3 V (vs. Ag/AgCl). Cyclic voltammetry (CV) revealed that nitrate reduction in the voltage range of - 0.3 V to - 1.4 V played an essential role in the formation of TiO2. The mechanism for TiO2 nanotube formation has been elucidated, paving the way for the future tailoring of metal oxide nanostructures by templated electrodeposition. © 2014 Elsevier B.V.

Effect of coating current density on the wettability of electrodeposited copper thin film on aluminum substrate

Directory of Open Access Journals (Sweden)

Arun Augustin

2016-09-01

Full Text Available Copper is the only one solid metal registered by the US Environmental Protection Agency as an antimicrobial touch surface. In touch surface applications, wettability of the surface has high significance. The killing rate of the harmful microbes depends on the wetting of pathogenic solution. Compared to the bulk copper, coated one on aluminum has the advantage of economic competitiveness and the possibility of manufacturing complex shapes. In the present work, the copper coating on the aluminum surface has successfully carried out by electrodeposition using non cyanide alkaline bath. To ensure good adhesion strength, the substrate has been pre-zincated prior to copper deposition. The coating current density is one of the important parameters which determine the nucleation density of the copper on the substrate. To understand the effect of current density on wettability, the coating has done at different current densities in the range of 3 A dm−2 to 9 A dm−2 for fixed time interval. The grain size has been measured from TEM micrographs and showed that as current density increases, grain size reduces from 62 nm to 35 nm. Since the grain size reduces, grain boundary volume has increases. As a result the value of strain energy (calculated by Williamson–Hall method has increased. The density of nodular morphology observed in SEM analysis has been increased with coating current density. Further, wettability studies with respect to double distilled water on the electrodeposited copper coatings which are coated at different current densities are carried out. At higher current density the coating is more wettable by water because at these conditions grain size of the coating decreases and morphology of grain changes to a favorable dense nodularity.

Electrodeposition of milligram amounts of uranium on electropolished stainless steel disks

International Nuclear Information System (INIS)

Aggarwal, S.K.; Shah, P.M.; Duggal, R.K.; Jain, H.C.

1991-01-01

Investigations have been carried out for the electrodeposition of milligram amounts of uranium on electropolished stainless steel disks with an objective of preparing good quality sources for α-spectrometric studies on uranium. The parameters studied include the vatiation of electrodeposition yield as a function of voltage, time, distance between the cathode and anode, and the volume of 0.2M ammonium oxalate solution. The conditions selected for preparing good quality sources with nearly 100% yield were: electrodeposition voltage 25 V, time of deposition 15 min, volume of 0.2M ammonium oxalate solution in the cell 4 ml and a distance of 2 cm between the cathode and anode. The sources prepared using this method have been used successfully for the α-spectrometric determination of 234 U/ 238 U ratios in uranium samples. (author) 6 refs.; 4 figs

Use of carriers for to electrodeposited radium 226

International Nuclear Information System (INIS)

Iturbe, J.L.

1991-10-01

The form of the energy distribution of a monoenergetic alpha particle starting from some emitting source of these particles, it depends on the quantity of material that its cross before being detected. Some authors deposit to the radium-226 by means of direct evaporation of the solution on metallic supports, on millipore paper and by electrodeposition. Some other ones place the radium solution in scintillation liquid, to quantify it by this technique. The objective of the present work is using carriers with the same oxidation state of the radium, that is to say of 2 + , for treating to be electrodeposited to the radium-226 with the biggest possible percentage for later use the alpha spectroscopy technique to quantify it. The carriers that have been used until its they are barium and zinc in form of barium chloride, zinc nitrate and zinc sulfate. The first results indicate that with the zinc solution a yield of 40% of electrodeposited radium has been reached. (Author)

Copper-zinc electrodeposition in alkaline-sorbitol medium: Electrochemical studies and structural, morphological and chemical composition characterization

Science.gov (United States)

de Almeida, M. R. H.; Barbano, E. P.; de Carvalho, M. F.; Tulio, P. C.; Carlos, I. A.

2015-04-01

The galvanostatic technique was used to analyze the electrodeposition of Cu-Zn on to AISI 1010 steel electrode from an alkaline-sorbitol bath with various proportions of the metal ions in the bath: Cu70/Zn30, Cu50/Zn50 and Cu30/Zn70. Coloration of Cu-Zn films were whitish golden, light golden, golden/gray depending on the Cu2+/Zn2+ ratios in the electrodeposition bath, deposition current density (jdep) and charge density (qdep). The highest current efficiency was ∼54.0%, at jdep -1.0 mA cm-2 and qdep 0.40 C cm-2 in the Cu70/Zn30 bath. Energy dispersive spectroscopy indicated that electrodeposits produced from the bath Cu70/Zn30 showed higher Cu content at lower jdep. Also, for same jdep the Cu content increased with qdep. Scanning electron microscopy showed that Cu-Zn electrodeposits of high quality were obtained from the Cu70/Zn30 bath, since the films were fine-grained, except the obtained at jdep -20.0 mA cm-2 and qdep 10.0 C cm-2. Also, these electrodeposits did not present cracks. X-ray analysis of the Cu-Zn electrodeposits obtained at jdep -8.0, -20.0 and -40.0 mA cm-2, in each case, with qdep 2.0 and 10.0 C cm-2, in the Cu70/Zn30 bath, suggested the occurrence of a mixture of the following phases, CuZn, CuZn5 and Cu5Zn8. Galvanostatic electrodeposits of Cu-Zn obtained from sorbitol-alkaline baths exhibited whitish golden color, with good prospects for industrial applications, especially for decorative purposes.

Electrodeposition of flake-like Cu{sub 2}O on vertically aligned two-dimensional TiO{sub 2} nanosheet array films for enhanced photoelectrochemical properties

Energy Technology Data Exchange (ETDEWEB)

Yang, Lei [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Co-operative Innovation Research Center for Weak Signal-Detecting Materials and Devices Integration, Anhui University, Hefei 230601 (China); Institute of Applied Physics AOA, Hefei 230031 (China); Zhang, Miao; Zhu, Kerong [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Lv, Jianguo [School of Electronic & Information Engineering, Hefei Normal University, Hefei 230601 (China); He, Gang [School of Physics & Material Science, Anhui University, Hefei 230601 (China); Sun, Zhaoqi, E-mail: szq@ahu.edu.cn [School of Physics & Material Science, Anhui University, Hefei 230601 (China)

2017-01-01

Highlights: • Flake-like Cu{sub 2}O/TNS with exposed {001} facets constructed p-n heterostructure. • The TNS arrays were used as starting substrates for Cu{sub 2}O growth. • The Cu{sub 2}O/TNS prepared at −0.4 V exhibits the best photoelectrochemical property. - Abstract: A novel Cu{sub 2}O/TNS composite structure of single crystal TiO{sub 2} nanosheet (TNS) arrays decorated with flake-like Cu{sub 2}O were synthesized by a facile hydrothermal reaction followed by the electrodeposition process. The effects of deposition potential on the microstructure, morphology, and optical property of the thin films were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and UV–vis spectrophotometer. When the deposition potential is higher than −0.4 V, peaks corresponding to Cu appear, meanwhile, flake-like Cu{sub 2}O become agglomerating, and transform into dense Cu{sub 2}O particles. Additionally, photoelectrochemical experiments indicate that the films deposited at −0.4 V show the lowest resistivity and highest exciton separation efficiency. This enhanced photoelectrochemical properties can be explained by synergistic effect of p-type flake-like Cu{sub 2}O and n-type TiO{sub 2} heterojunctions combined with two-dimensional TiO{sub 2} nanosheet with exposed highly reactive {001} facets.

Hydrodynamic voltammetric studies of the oxygen reduction at gold nanoparticles-electrodeposited gold electrodes

International Nuclear Information System (INIS)

El-Deab, Mohamed S.; Ohsaka, Takeo

2002-01-01

The electrocatalytic reduction of oxygen at Au nanoparticles-electrodeposited Au electrodes has been studied using rotating disk electrode (RDE) voltammetry in 0.5 M H 2 SO 4 . Upon analyzing and comparison of the limiting currents data obtained at various rotation speeds of this RDE with those obtained at the bulk Au electrode, an effective value of the number of electrons, n, involved in the electrochemical reduction of O 2 was estimated to be ca. 4 for the former electrode and ca. 3 for the bulk Au electrode at the same potential of -350 mV versus Ag/AgCl/KCl(sat.). This indicates the higher possibility of further reduction and decomposition of H 2 O 2 at Au nanoparticles-electrodeposited Au electrode in this acidic medium. The reductive desorption of the self-assembled monolayer of cysteine, which was formed on the Au nanoparticles-electrodeposited Au electrode, was used to monitor the change of the specific activity of the bulk Au electrode upon the electrodeposition of the Au nanoparticles

High dielectric permittivity in the microwave region of SrBi2Nb2O9 (SBN) added La2O3, PbO and Bi2O3, obtained by mechanical alloying

Science.gov (United States)

Rocha, M. J. S.; Silva, P. M. O.; Theophilo, K. R. B.; Sancho, E. O.; Paula, P. V. L.; Silva, M. A. S.; Honorato, S. B.; Sombra, A. S. B.

2012-08-01

This paper presents the microwave dielectric properties and a structural study of SrBi2Nb2O9 (SBN) added La2O3, PbO or Bi2O3 obtained by a solid state procedure. High-energy mechanical milling was used to reduce the particle size, which allows for a better shaping of the green body and an increased reactivity. The mechanical milling activation process produced a reduced sintering temperature in the material, decreasing the loss of the volatile elements and controlling the growth of the grain that is produced when a high temperature is required to obtain dense ceramics. The incorporation of La3+, or Pb2+, or Bi3+ of different amounts (0, 3, 5, 10 and 15 wt%) was used to improve the densification without changing the crystal structure, since with a low doping content these ions can occupy the A site of the perovskite blocks; they can also occupy the Bi3+ sites in Bi2O3 layers. A single orthorhombic phase was formed after calcination at 800 °C for 2 h. X-ray diffraction, Fourier transformation, infrared and Raman spectroscopy have been carried out in order to investigate the effects of doping on SBN. The dielectric permittivity (ɛ‧r) and loss in the microwave region (2-4 GHz) of SBN ceramics with additions of Bi2O3, La2O3 and PbO were studied. Higher values of permittivity (ɛr‧ = 154.6) have been obtained for the SBN added La (15 wt%) a lower loss (tg δ = 0.01531) was also achieved in the SBN added La (15 wt%) sample with PVA and TEOS, respectively. The samples that showed the highest dielectric permittivities were all lanthanum doped, all with values of permittivity above 90. A comparative study associated with different types of binders was completed (with glycerin, PVA and TEOS). This procedure allowed us to obtain phases at lower temperatures than usually appear in the literature. The microwave dielectric properties (permittivity and loss) in the region 2-4 GHz, were studied for all samples. The structural and microwave dielectric properties of SBN show a

The effect of different component ratios in block polymers and processing conditions on electrodeposition efficiency onto titanium

Energy Technology Data Exchange (ETDEWEB)

Fukuhara, Yusuke; Kyuzo, Megumi [Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Tsutsumi, Yusuke [Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan); Nagai, Akiko [Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan); Chen, Peng [Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan); Hanawa, Takao, E-mail: hanawa.met@tmd.ac.jp [Department of Materials Engineering, School of Engineering, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-8656 (Japan); Institute of Biomaterials and Bioengineering, Tokyo Medical and Dental University, 2-3-10 Kanda-surugadai, Chiyoda-ku, Tokyo 101-0062 (Japan)

2015-11-15

Graphical abstract: - Highlights: • MPC polymers with an ability of electrodeposition were synthesized. • MPC polymers were immobilized on titanium substrates by electrodeposition. • Immobilization by electrodeposition of MPC polymer decreased water contact angle and protein adsorption. • Length of MPC unit and electrodeposition time did not influence water contact angle and protein adsorption. - Abstract: 2-Methacryloyloxyethyl phosphorylcholine (MPC) polymers for electrodeposition to titanium surfaces were synthesized. The polymers were block-type copolymers composed of a poly(MPC) segment and a poly(2-aminoethylmethacrylate (AEMA)) segment, which could electronically adsorb to a titanium oxide film on the titanium surface. The polymer was synthesized as expected by nuclear magnetic resonance and gel permeation chromatography. In a 0.26 mmol L{sup −1} PMbA solution adjusted to pH 11, −3.0 V (vs. an Ag/AgCl electrode) was applied to a titanium substrate for 300 s. We evaluated the effects of the molecular structure of poly(MPC-block-AEMA) (PMbA) with a different polymerization degree of MPC unit, whereas the polymerization degree of the AEMA units was fixed. The 15-min electrodeposition of PMbA100 was the most efficient condition in this study. On the other hand, the results of the water contact angle and the amount of adsorbed protein did not change, even when altering the MPC unit number and electrodeposition time. This indicates that the immobilization by electrodeposition of PMbA is important for the inhibition of protein adsorption, while the polymerization degree of the MPC unit and the electrodeposition time do not influence them. This study will enhance the understanding of effective polymer structures for electrodeposition and electrodeposition conditions.

High Discharge Rate Electrodeposited Zinc Electrode for Use in Alkaline Microbattery

Directory of Open Access Journals (Sweden)

A. L. Nor Hairin

2012-01-01

Full Text Available High discharge rate zinc electrode is prepared from electrodeposition process. The electrolytic bath consists of zinc chloride as the metal source and ammonium chloride as the supporting electrolyte. The concentration of the supporting electrolyte is varied from zero until 4 M, while the concentration of zinc chloride is fixed at 2 M. The aim is to produce a porous zinc coating with an enhanced and intimate interfacial area per unit volume. These characteristics shall contribute towards reduced ohmic losses, improved active material utilization, and subsequently producing high rate capacity electrochemical cell. Nitrogen physisorption at 77 K is used to measure the BET surface area and pore volume density of the zinc electrodeposits. The electrodeposited zinc electrodes are then fabricated into alkaline zinc-air microbattery measuring 1 cm2 area x ca. 305 µm thick. The use of inorganic MCM-41 membrane separator enables the fabrication of a compact cell design. The quality of the electrodeposited zinc electrodes is gauged directly from the electrochemical performance of zinc-air cell. Zinc electrodeposits prepared from electrolytic bath of 2 M NH4Cl produces the highest discharge capacity.ABSTRAK: Elektrod zink dengan kadar discas tinggi telah dihasilkan dengan proses saduran elektrokimia. Takungan elektrolit terdiri daripada zink klorida sebagai sumber logam dan ammonium klorida sebagai elektrolit sokongan. Kepekatan elektrolit sokongan diubah daripada sifar hingga 4 M, sementara kepekatan zink klorida ditetapkan pada 2 M. Ini bertujuan untuk mendapatkan saduran zink yang poros dengan luas permukaan per unit isipadu dan sentuhan antaramuka yang dipertingkatkan. Ciri-ciri ini akan menyumbang terhadap pengurangan kehilangan disebabkan kerintangan, pertambahan dalam gunapakai bahan aktif dan akhirnya menghasilkan sel elektrokimia berprestasi tinggi. Physisorpsi nitrogen pada 77 K telah digunakan untuk mengukur luas permukaan BET dan isipadu liang

PBO Borehole Strainmeters: 2017 Episodic Tremor and Slip Event for Southern Vancouver Island, BC, Canada through Olympia, WA, USA

Science.gov (United States)

Van Boskirk, E. J.; Hodgkinson, K. M.; Gottlieb, M. H.; Johnson, W.; Henderson, D. B.; Mencin, D.; Mattioli, G. S.

2017-12-01

The Plate Boundary Observatory's (PBO) borehole strainmeters along the Cascadia Subduction Zone (CSZ) record the development and migration of Episodic Tremor and Slip (ETS). Along the southern Vancouver Island to Olympia, WA portion of the CSZ ETS events seem to repeat every 14 months. ETS events are non-volcanic tremor swarms that occur over periods of weeks, often migrating along segments of the subduction zone and can release the energy equivalent to a M7 or greater earthquake. Each ETS event is different; initial propagation location, ETS movement, duration, and direction all vary. Constraints provided by strainmeter observations of ETS events illuminate strain release patterns along the subducting slab interface and may help resolve questions regarding the location of the locked zone of the slab and what role ETS events play in the CSZ earthquake cycle. The 2017 CSZ ETS began in early February continuing through early April. Beginning in the northern Olympic Peninsula, near Port Angeles, it migrated south towards Olympia over the course of a week. After a two week pause it resumed under the Straits of Juan de Fuca and propagated northwest under Vancouver Island. There are 15 PBO borehole strainmeters along this segment, and ETS strain observations correlate with seismic and GPS measurements. The PBO borehole strainmeters are sensitive even over great distances from the ETS epicenters, and observe compression or extension relative to the ETS migration. Openly available PBO borehole strainmeter data used by the community has made significant contributions to understanding the ETS process, including the determination that ETS slip is tidally modulated. Data are publically available through UNAVCO and IRIS, which provide links to online tutorials and scripts. There are 32 strainmeters covering the CSZ from southern Vancouver Island, Canada to northern California, USA, and data spans back to 2005. Each site has a Gladwin tensor borehole strainmeter, a Malin three

Single potential electrodeposition of nanostructured battery materials for lithium-ion batteries

Science.gov (United States)

Mosby, James Matthew

The increasing reliance on portable electronics is continuing to fuel research in the area of low power lithium-ion batteries, while a new surge in research for high power lithium-ion batteries has been sparked by the demand for plug-in hybrid electric vehicles (PHEV) and plug-in electric vehicles (PEV). To compete with current lead-acid battery chemistry, a few of the shortcomings of lithium-ion battery chemistry need to be addressed. The three main drawbacks of lithium-ion batteries for this application are: (1) low power density, (2) safety, and (3) the high cost of manufacturing. This dissertation covers the development of a low cost fabrication technique for an alternative anode material with high surface area geometries. The anode material is safer than the conventional anode material in lithium-ion batteries and the high surface area geometries permit higher power densities to be achieved. Electrodeposition is an inexpensive alternative method for synthesizing materials for electronics, energy conversion and energy storage applications relative to traditional solid state techniques. These techniques led to expensive device fabrication. Unlike most solid state synthesis routes, electrodeposition can usually be performed from common solutions and at moderate conditions. Three other benefits of using electrodeposition are: (1) it allows precise control of composition and crystallinity, (2) it provides the ability to deposit on complex shapes, and (3) it can deposit materials with nanoscale dimensions. The use of electrodeposition for alternative anode materials results in the deposition of the material directly onto the current collector that is used for the battery testing and applications without the need of additional binders and with excellent electrical contact. While this improves the characterization of the material and lowers the weight of the non-active materials within a battery, it also allows the anode to be deposited onto current collectors with

DC electrodeposition of NiGa alloy nanowires in AAO template

Energy Technology Data Exchange (ETDEWEB)

Maleki, K. [Nanomaterials Group, Department of Materials Engineering, Tarbiat Modares University, Iran, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of); Sanjabi, S., E-mail: sanjabi@modares.ac.ir [Nanomaterials Group, Department of Materials Engineering, Tarbiat Modares University, Iran, P.O. Box: 14115-143, Tehran (Iran, Islamic Republic of); Alemipour, Z. [Department of Physics, University of Kurdistan, Sanandaj (Iran, Islamic Republic of)

2015-12-01

NiGa alloy nanowires were electrodeposited from an acidic sulfate bath into nanoporous anodized alumina oxide (AAO). This template was fabricated by two-step anodizing. The effects of bath composition and current density were explored on the Ga content of electrodeposited nanowires. The Ga content in the deposits was increased by increasing both Ga in the bath composition and electrodepositing current density. The NiGa alloy nanowires were synthesized for Ga content up to 2–4% without significant improving the magnetic properties. Above this threshold Ga clusters were formed and decreased the magnetic properties of the nanowires. For Ga content of the alloy above 30%, the wires were too short and incomplete. X-ray diffraction patterns reveal that the significant increase of Ga content in the nanowires, changes the FCC crystal structure of Ni to an amorphous phase. It also causes a sizeable increase in the Ga cluster size; these both lead to a significant reduction in the coercivity and the magnetization respectively. - Highlights: • NiGa alloy nanowires were electrodeposited from acidic sulphate baths into nanoporous anodized alumina oxide (AAO) template. • The Ga content was increased by increasing the Ga in the bath composition and electrodeposition current density. • The magnetic parameters such as coercivity and magnetization were not changed for the alloy nanowire with Ga content less than 4%.

Potentiostatic electro-deposition of 241Am using room temperature ionic liquids

International Nuclear Information System (INIS)

Sankhe, R.H.; Mirashi, N.N.; Arijit Sengupta; Murali, M.S.

2015-01-01

An attempt was made for the potentiostatic electrodeposition of 241 Am using six different room temperature ionic liquids (RTILs). Effect of electrodeposition time on the % of electrodeposition of 241 Am, pH change of the solution and the temperature change of the systems were investigated. It was observed that for water immiscible RTILs, the least viscous RTIL gave the best yield (when mixed with iso-propanol), while for water miscible RTILs, reverse trend was observed (when mixed with water). Out of all water immiscible RTILs under consideration for the present case, the octyl-methyl-pyrrolidinium bis(trifluoromethylsulfonyl)imide (C 8 mpyNTf 2 ) in isopropanol was found to yield almost quantitative (99.6 %) electrodeposition of 241 Am within 45 min whereas the most effective system was found to be C 8 mimBr with ∼90 % of 241 Am deposited on the electrode for water miscible RTILs. To the best of our knowledge, this is the first approach ever been reported in the literature. (author)

Spin texture of the surface state of three-dimensional Dirac material Ca3PbO

Science.gov (United States)

Kariyado, Toshikaze

2015-04-01

The bulk and surface electronic structures of a candidate three-dimensional Dirac material Ca3PbO and its family are discussed especially focusing on the spin texture on the surface states. We first explain the basic features of the bulk band structure of Ca3PbO, such as emergence of Dirac fermions near the Fermi energy, and compare it with the other known three-dimensional Dirac semimetals. Then, the surface bands and spin-texture on them are investigated in detail. It is shown that the surface bands exhibit strong momentum-spin locking, which may be useful in some application for spin manipulation, induced by a combination of the inversion symmetry breaking at the surface and the strong spin-orbit coupling of Pb atoms. The surface band structure and the spin-textures are sensitive to the surface types.

Spin texture of the surface state of three-dimensional Dirac material Ca3PbO

International Nuclear Information System (INIS)

Kariyado, Toshikaze

2015-01-01

The bulk and surface electronic structures of a candidate three-dimensional Dirac material Ca 3 PbO and its family are discussed especially focusing on the spin texture on the surface states. We first explain the basic features of the bulk band structure of Ca 3 PbO, such as emergence of Dirac fermions near the Fermi energy, and compare it with the other known three-dimensional Dirac semimetals. Then, the surface bands and spin-texture on them are investigated in detail. It is shown that the surface bands exhibit strong momentum-spin locking, which may be useful in some application for spin manipulation, induced by a combination of the inversion symmetry breaking at the surface and the strong spin-orbit coupling of Pb atoms. The surface band structure and the spin-textures are sensitive to the surface types. (paper)

Layered Ni(OH)2-Co(OH)2 films prepared by electrodeposition as charge storage electrodes for hybrid supercapacitors.

Science.gov (United States)

Nguyen, Tuyen; Boudard, Michel; Carmezim, M João; Montemor, M Fátima

2017-01-04

Consecutive layers of Ni(OH) 2 and Co(OH) 2 were electrodeposited on stainless steel current collectors for preparing charge storage electrodes of high specific capacity with potential application in hybrid supercapacitors. Different electrodes were prepared consisting on films of Ni(OH) 2 , Co(OH) 2 , Ni 1/2 Co 1/2 (OH) 2 and layered films of Ni(OH) 2 on Co(OH) 2 and Co(OH) 2 on Ni(OH) 2 to highlight the advantages of the new architecture. The microscopy studies revealed the formation of nanosheets in the Co(OH) 2 films and of particles agglomerates in the Ni(OH) 2 films. Important morphological changes were observed in the double hydroxides films and layered films. Film growth by electrodeposition was governed by instantaneous nucleation mechanism. The new architecture composed of Ni(OH) 2 on Co(OH) 2 displayed a redox response characterized by the presence of two peaks in the cyclic voltammograms, arising from redox reactions of the metallic species present in the layered film. These electrodes revealed a specific capacity of 762 C g -1 at the specific current of 1 A g -1 . The hybrid cell using Ni(OH) 2 on Co(OH) 2 as positive electrode and carbon nanofoam paper as negative electrode display specific energies of 101.3 W h g -1 and 37.8 W h g -1 at specific powers of 0.2 W g -1 and 2.45 W g -1 , respectively.

Electrodeposited nanoparticles: properties and photocatalytic applications

OpenAIRE

Sheridan, Eoin E.

2009-01-01

The work presented in this thesis reports on fundamental studies into electrodeposition of gold and silver nanoparticulate spheroids on a conducting substrate, Fluorine-doped tin-oxide, and the manipulation of the electrodeposition conditions in order to influence and control the size and surface concentration of spheroids. Methods to control the deposition included chemical modification of the surface with an adsorbed monolayer of 3-aminopropyldimethylmethoxysilane, and manipulation of...

Electrodeposition mechanism of quaternary compounds Cu2ZnSnS4: Effect of the additives

Science.gov (United States)

Tang, Aiyue; Li, Zhilin; Wang, Feng; Dou, Meiling; Liu, Jingjun; Ji, Jing; Song, Ye

2018-01-01

The electrodeposition mechanism of pure phase Cu2ZnSnS4 (CZTS) thin film with subsequent annealing was investigated in detail. An electrolyte design principle of quaternary compounds was proposed. The complex ions of Cu(H2C6H5O7)+, Cu2(C6H5O7)+, Zn(C4H5O6)+, Sn(H2C6H5O7)+ and Sn2(C6H5O7)+, which influenced the reduction process and played important roles in co-deposition, were identified by UV spectra. Electrochemical studies indicated that trisodium citrate and tartaric acid could narrow the co-deposition potential range of the four elements to -0.8 V to -1.2 V (vs. SCE). The cause was the synergetic effect that trisodium citrate inhibited the reduction of Cu2+ and Sn2+ and tartaric acid promoted the reduction of Zn2+. The reduction of S2O32- was mainly attributed to the induction effect of the metallic ions, and the H+ dissociated from tartaric acid could also promote the cathode process of S2O32-. The reaction mechanism could be summarized as the following steps: (I) Cu(H2C6H5O7)+, Cu2(C6H5O7)+ → Cu, Sn(H2C6H5O7)+, Sn2(C6H5O7)+ → Sn, Zn(C4H5O6)+ → Zn; (II) the desorption of (H2C6H5O7)- and (C6H5O7)-, and the reduction of S2O32- induced by metallic ions and H+. The mechanism studies provided a path of electrolyte design for multicomponent compounds.

Microstructure and Properties of Ni and Ni/Al2O3 Coatings Electrodeposited at Various Current Densities

Directory of Open Access Journals (Sweden)

Góral A.

2016-03-01

Full Text Available The study presents investigations of an influence of various direct current densities on microstructure, residual stresses, texture, microhardness and corrosion resistance of the nickel coatings electrodeposited from modified Watt’s baths. The properties of obtained coatings were compared to the nano-crystalline composite Ni/Al2O3 coatings prepared under the same plating conditions. The similarities and differences of the obtained coatings microstructures visible on both their surfaces and cross sections and determined properties were presented. The differences in the growth character of the Ni matrix and in the microstructural properties were observed. All electrodeposited Ni and Ni/Al2O3 coatings were compact and well adhering to the steel substrates. The thickness and the microhardness of the Ni and Ni/Al2O3 deposits increased significantly with the current density in the range 2 - 6 A/dm2. Residual stresses are tensile and they reduced as the current density increased. The composite coatings revealed better protection from the corrosion of steel substrate than pure nickel in solution 1 M NaCl.

Effect of tungsten (W) on structural and magnetic properties of electroplated NiFe thin films for MEMS applications

Science.gov (United States)

Kannan, R.; Devaki, P.; Premkumar, P. S.; Selvambikai, M.

2018-04-01

Electrodeposition of nanocrystalline NiFe and NiFeW thin films were carried out from ammonium citrate bath at a constant current density and controlled pH of 8 by varying the bath temperature from 40 °C to 70 °C. The surface morphology and chemical composition of the electrodeposited NiFe and NiFeW soft magnetic thin films were studied by using SEM and EDAX. The SEM micrographs of the films coated at higher electrodeposited bath temperature have no micro cracks and also the films have more uniform surface morphology. The existence of crystalline nature of the coated films were analysed by XRD. The presence of predominant peaks in x-ray diffraction pattern (compared with JCPDS data) reveal that the average crystalline size was in the order of few tens of nano meters. The magnetic properties such as coercivity, saturation magnetization and magnetic flux density have been calculated from vibrating sample magnetometer analysis. The VSM result shows that the NiFeW thin film synthesised at 70 °C exhibit the lower coercivity with higher saturation magnetization. The hardness and adhesion of the electroplated films have been investigated. Reasons for variation in magnetic properties and structural characteristics are also discussed. The electroplated NiFe and NiFeW thin films can be used for Micro Electro Mechanical System (MEMS) applications due to their excellent soft magnetic behaviour.

Swift heavy ion induced modifications in optical and electrical properties of cadmium selenide thin films

Science.gov (United States)

Choudhary, Ritika; Chauhan, Rishi Pal

2017-07-01

The modification in various properties of thin films using high energetic ion beam is an exciting area of basic and applied research in semiconductors. In the present investigations, cadmium selenide (CdSe) thin films were deposited on ITO substrate using electrodeposition technique. To study the swift heavy ion (SHI) induced effects, the deposited thin films were irradiated with 120 MeV heavy Ag9+ ions using pelletron accelerator facility at IUAC, New Delhi, India. Structural phase transformation in CdSe thin film from metastable cubic phase to stable hexagonal phase was observed after irradiation leading to decrease in the band gap from 2.47 eV to 2.12 eV. The phase transformation was analyzed through X-ray diffraction patterns. During SHI irradiation, Generation of high temperature and pressure by thermal spike along the trajectory of incident ions in the thin films might be responsible for modification in the properties of thin films.[Figure not available: see fulltext.

Orientations and Relative Shear-strain Response Coefficients for PBO Gladwin Tensor Strainmeters from Teleseismic Love Waves

Science.gov (United States)

Roeloffs, E. A.

2016-12-01

A Gladwin Tensor Strainmeter (GTSM) is designed to measure changes of the horizontal strain tensor, derived as linear combinations of radial elongations or contractions of the strainmeter's cylindrical housing measured at four azimuths. Each radial measurement responds to changes in the areal, horizontal shear and vertical components of the strain tensor in the surrounding formation. The elastic response coefficients to these components depend on the relative elastic moduli of the housing, formation, and cement. These coefficients must be inferred for each strainmeter after it is cemented into its borehole by analyzing the instrument response to well-characterized strain signals such as earth tides. For some GTSMs of the Earthscope Plate Boundary Observatory (PBO), however, reconciling observed earth-tide signals with modeled tidal strains requires response coefficients that differ substantially between the instrument's four gauges, and/or orientation corrections of tens of degrees. GTSM response coefficients can also be estimated from high-resolution records of teleseismic Love waves from great earthquakes around the world. Such records can be used in conjunction with apparent propagation azimuths from nearby broadband seismic stations to determine the GTSM's orientation. Knowing the orientation allows the ratios between the shear strain response coefficients of a GTSM's four gauges to be estimated. Applying this analysis to 14 PBO GTSMs confirms that orientations of some instruments differ significantly from orientations measured during installation. Orientations inferred from earth-tide response tend to agree with those inferred from Love waves for GTSMs far from tidal water bodies, but to differ for GTSMs closer to coastlines. Orientations derived from teleseismic Love waves agree with those estimated by Grant and Langston (2010) using strains from a broadband seismic array near Anza, California. PBO GTSM recordings of teleseismic Love waves show differences of

Electrochemically modified crystal orientation, surface morphology and optical properties using CTAB on Cu2O thin films

Directory of Open Access Journals (Sweden)

Karupanan Periyanan Ganesan

Full Text Available Cuprous oxide (Cu2O thin films with different crystal orientations were electrochemically deposited in the presence of various molar concentrations of cetyl trimethyl ammonium bromide (CTAB on fluorine doped tin oxide (FTO glass substrate using standard three electrodes system. X-ray diffraction (XRD studies reveal cubic structure of Cu2O with (111 plane orientation, after addition of CTAB in deposition solution, the orientation of crystal changes from (111 into (200 plane. Scanning electron microscope (SEM images explored significant variation on morphology of Cu2O thin films deposited with addition of CTAB compared to without addition of CTAB. Photoluminescence (PL spectra illustrate that the emission peak around at 650 nm is attributed to near band edge emission, and the film prepared at the 3 mM of CTAB exhibits much higher intensity than that of the all other films. UV–Visible spectra show optical absorption in the range of 480–610 nm and the highest transparency of Cu2O film prepared at the concentration of 3 mM CTAB. The optical band gap is increased in the range between 2.16 and 2.45 eV with increasing the CTAB concentrations. Keywords: Cuprous oxide, Crystal orientation, Electrodeposition and cubic structure

Electrodeposition of Zn and Cu–Zn alloy from ZnO/CuO precursors in deep eutectic solvent

Energy Technology Data Exchange (ETDEWEB)

Xie, Xueliang [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Zou, Xingli, E-mail: xinglizou@shu.edu.cn [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Lu, Xionggang, E-mail: luxg@shu.edu.cn [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Lu, Changyuan; Cheng, Hongwei; Xu, Qian [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Zhou, Zhongfu [State Key Laboratory of Advanced Special Steel & Shanghai Key Laboratory of Advanced Ferrometallurgy & School of Materials Science and Engineering, Shanghai University, Shanghai 200072 (China); Institute of Mathematics and Physics, Aberystwyth University, Aberystwyth SY23 3BZ (United Kingdom)

2016-11-01

Graphical abstract: Micro/nanostructured Zn and Cu–Zn alloy films have been electrodeposited directly from ZnO/CuO precursors in ChCl/urea-based DES, the typical nucleation-growth mechanism and the micro/nanostructures-formation process are determined. Display Omitted - Highlights: • Micro/nanostructured Zn films have been electrodeposited directly from ZnO precursor in deep eutectic solvent (DES). • The morphology of the Zn electrodeposits depends on the cathodic potential and temperature. • The electrodeposited Zn films exhibit homogeneous morphologies with controllable particle sizes and improved corrosion resistance. • Cu–Zn alloy films have also been electrodeposited directly from their metal oxides precursors in DES. - Abstract: The electrodeposition of Zn and Cu–Zn alloy has been investigated in choline chloride (ChCl)/urea (1:2 molar ratio) based deep eutectic solvent (DES). Cyclic voltammetry study demonstrates that the reduction of Zn(II) to Zn is a diffusion-controlled quasi-reversible, one-step, two electrons transfer process. Chronoamperometric investigation indicates that the electrodeposition of Zn on a Cu electrode typically involves three-dimensional instantaneous nucleation with diffusion-controlled growth process. Micro/nanostructured Zn films can be obtained by controlling the electrodeposition potential and temperature. The electrodeposited Zn crystals preferentially orient parallel to the (101) plane. The Zn films electrodeposited under more positive potentials and low temperatures exhibit improved corrosion resistance in 3 wt% NaCl solution. In addition, Cu–Zn alloy films have also been electrodeposited directly from CuO–ZnO precursors in ChCl/urea-based DES. The XRD analysis indicates that the phase composition of the electrodeposited Cu–Zn alloy depends on the electrodeposition potential.

Controllable Growth of Ga Film Electrodeposited from Aqueous Solution and Cu(In,Ga)Se2 Solar Cells.

Science.gov (United States)

Bi, Jinlian; Ao, Jianping; Gao, Qing; Zhang, Zhaojing; Sun, Guozhong; He, Qing; Zhou, Zhiqiang; Sun, Yun; Zhang, Yi

2017-06-07

Electrodepositon of Ga film is very challenging due to the high standard reduction potential (-0.53 V vs SHE for Ga 3+ ). In this study, Ga film with compact structure was successfully deposited on the Mo/Cu/In substrate by the pulse current electrodeposition (PCE) method using GaCl 3 aqueous solution. A high deposition rate of Ga 3+ and H + can be achieved by applying a large overpotential induced by high pulse current. In the meanwhile, the concentration polarization induced by cation depletion can be minimized by changing the pulse frequency and duty cycle. Uniform and smooth Ga film was fabricated at high deposition rate with pulse current density 125 mA/cm 2 , pulse frequency 5 Hz, and duty cycle 0.25. Ga film was then selenized together with electrodeposited Cu and In films to make a CIGSe absorber film for solar cells. The solar cell based on the Ga film presents conversion efficiency of 11.04%, fill factor of 63.40%, and V oc of 505 mV, which is much better than those based on the inhomogeneous and rough Ga film prepared by the DCE method, indicating the pulse current electrodeposition process is promising for the fabrication of CIGSe solar cell.

Nanocrystalline Ni-Co Alloy Synthesis by High Speed Electrodeposition

OpenAIRE

Idris, Jamaliah; Christian, Chukwuekezie; Gaius, Eyu

2013-01-01

Electrodeposition of nanocrystals is economically and technologically viable production path for the synthesis of pure metals and alloys both in coatings and bulk form. The study presents nanocrystalline Ni-Co alloy synthesis by high speed electrodeposition. Nanocrystalline Ni-Co alloys coatings were prepared by direct current (DC) and deposited directly on steel and aluminum substrates without any pretreatment, using high speed electrodeposition method. The influence of the electrolysis par...

Structural and electrochemical analysis of chemically synthesized microcubic architectured lead selenide thin films

Science.gov (United States)

Bhat, T. S.; Shinde, A. V.; Devan, R. S.; Teli, A. M.; Ma, Y. R.; Kim, J. H.; Patil, P. S.

2018-01-01

The present work deals with the synthesis of lead selenide (PbSe) thin films by simple and cost-effective chemical bath deposition method with variation in deposition time. The structural, morphological, and electrochemical properties of as-deposited thin films were examined using characterization techniques such as X-ray diffraction spectroscopy (XRD), field-emission scanning electron microscopy (FE-SEM), X-ray photoelectron spectroscopy (XPS), cyclic voltammetry (CV), galvanostatic charge-discharge and electrochemical impedance spectroscopy. XRD reveals formation of rock salt phase cubic structured PbSe. FE-SEM images show the formation of microcubic structured morphology. The existence of the PbSe is confirmed from the XPS analysis. On the other hand, CV curves show four reaction peaks corresponding to oxidation [PbSe and Pb(OH)2] and reduction (PbO2 and Pb(OH)2) at the surface of PbSe thin films. The PbSe:2 sample deposited for 80 min. shows maximum specific capacitance of 454 ± 5 F g- 1 obtained at 0.25 mA cm- 2 current density. The maximum energy density of 69 Wh kg- 1 was showed by PbSe:2 electrode with a power density of 1077 W kg- 1. Furthermore, electrochemical impedance studies of PbSe:2 thin film show 80 ± 3% cycling stability even after 500 CV cycles. Such results show the importance of microcubic structured PbSe thin film as an anode in supercapacitor devices.

Electrodeposition of Ru in TiO_2 nanotubes: increase of photocatalytical activity and identification of deposition route

International Nuclear Information System (INIS)

Castelhano, Douglas Iafrate; Rodrigues, Christiane de Arruda; Bertazzoli, Rodnei

2014-01-01

TiO2 nanotubes are semiconductors widely used in heterogeneous photocatalysis processes. It has a band gap energy (E_b_g) of 3,2 eV and an photoactive crystalline structure (anatase). To increase the photocatalytic activity of this oxide, by lowering the Ebg and reduction of charge recombination rate, a modification of oxide crystalline layer was made with ruthenium, using electrochemical deposition at constant potential. TiO_2 layer was made by anodization process at 20V, followed by thermic treatment in 450 deg C and electrodeposition of Ru at constant potential. Voltammetric studies showed that Ru electrodeposition occurs in two stages, and in the second stage is the deposition of metallic Ru. Photocurrent studies showed that the amount of Ru in the oxide layer varies according with the applied potential and a significant increase of semiconductor activity is obtained with the introduction of small quantities of Ru, increasing at least 70% in current values. Morphological and crystallinity analysis were made using SEM and XRD. To identify and quantify Ru in TiO_2 was used WDS. (author)

Green synthesis of in situ electrodeposited rGO/MnO2 nanocomposite for high energy density supercapacitors

Science.gov (United States)

Rusi; Majid, S. R.

2015-11-01

This paper presents the preparation of in situ electrodeposited rGO/MnO2 nanocomposite as a binder-free electrode for supercapacitor application. The work describes and evaluates the performance of prepared electrode via green and facile electrodeposition technique of in situ rGO/MnO2-glucose carbon nanocomposites. The carbon content in the composite electrode increased after GO and D (+) glucose solution has been added in the deposition electrolyte. This study found that a suitable concentration of D (+) glucose in the deposition electrolyte can slow down the nucleation process of MnO2 particles and lead to uniform and ultrathin nanoflakes structure. The optimize electrode exhibited low transfer resistance and resulted on excellent electrochemical performance in three electrolyte systems viz. Na2SO4, KOH and KOH/K3Fe(CN)6 redox electrolytes. The optimum energy density and power density were 1851 Whkg-1 and 68 kWkg-1 at current density of 20 Ag-1 in mixed KOH/K3Fe(CN)6 electrolyte.

Physical and electrochemical properties of ZnO films fabricated from highly cathodic electrodeposition potentials

Science.gov (United States)

Ismail, Abdul Hadi; Abdullah, Abdul Halim; Sulaiman, Yusran

2017-03-01

The physical and electrochemical properties of zinc oxide (ZnO) film electrode that were prepared electrochemically were studied. ZnO was electrodeposited on ITO glass substrate by applying three different highly cathodic potentials (-1.3 V, -1.5 V, -1.7 V) in a solution containing 70 mM of Zn(NO3)2.xH2O and 0.1 M KCl with bath temperatures of 70 °C and 80 °C. The presence of ZnO was asserted from XRD analysis where the corresponding peaks in the spectra were assigned. SEM images revealed the plate-like hexagonal morphology of ZnO which is in agreement with the XRD analysis. The areal capacitance of the ZnO was observed to increase when the applied electrodeposition potential is increased from -1.3 V to -1.5 V. However, the areal capacitance is found to decrease when the applied electrodeposition potential is further increased to -1.7 V. The resistance of charge transfer (Rct) of the ZnO decreased when the applied electrodeposition potential varies from -1.3 V to -1.7 V due to the decreased particle size of ZnO when more cathodic electrodeposition potential is applied.

Electrodeposition of amine-terminatedpoly(ethylene glycol) to titanium surface

International Nuclear Information System (INIS)

Tanaka, Yuta; Doi, Hisashi; Iwasaki, Yasuhiko; Hiromoto, Sachiko; Yoneyama, Takayuki; Asami, Katsuhiko; Imai, Hachiro; Hanawa, Takao

2007-01-01

The immobilization of poly(ethylene glycol), PEG, to a solid surface is useful to functionalize the surface, e.g., to prevent the adsorption of proteins. No successful one-stage technique for the immobilization of PEG to base metals has ever been developed. In this study, PEG in which both terminals or one terminal had been modified with amine bases was immobilized onto a titanium surface using electrodeposition. PEG was dissolved in a NaCl solution, and electrodeposition was carried out at 310 K with - 5 V for 300 min. The thickness of the deposited PEG layer was evaluated using ellipsometry, and the bonding manner of PEG to the titanium surface was characterized using X-ray photoelectron spectroscopy after electrodeposition. The results indicated that a certain amount of PEG was adsorbed on titanium through both electrodeposition and immersion when PEG was terminated by amine. However, terminated amines existed at the surface of titanium and were combined with titanium oxide as N-HO by electrodeposition, while amines randomly existed in the molecule and showed an ionic bond with titanium oxide by immersion. The electrodeposition of PEG was effective for the inhibition of albumin adsorption. This process is useful for materials that have electroconductivity and a complex morphology

Electrodeposition of Radium

International Nuclear Information System (INIS)

Crespo, M.T.; Jimenez, A.S.

1996-01-01

A study of different electrodeposition methods of radium for its measurement by alpha-spectrometry is presented. The recommended procedure uses an aqueous solution of ammonium oxalate and nitric acid in the presence of microgram amounts of platinum as electrolyte

Microstructure and surface mechanical properties of pulse electrodeposited nickel

Energy Technology Data Exchange (ETDEWEB)

Ul-Hamid, A., E-mail: anwar@kfupm.edu.sa [Center of Research Excellence in Corrosion (CoRE-C), Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia); Dafalla, H.; Quddus, A.; Saricimen, H.; Al-Hadhrami, L.M. [Center of Research Excellence in Corrosion (CoRE-C), Research Institute, King Fahd University of Petroleum and Minerals, P.O. Box 1073, Dhahran 31261 (Saudi Arabia)

2011-09-01

The surface of carbon steel was modified by electrochemical deposition of Ni in a standard Watt's bath using dc and pulse plating electrodeposition. The aim was to compare the microstructure and surface mechanical properties of the deposit obtained by both techniques. Materials characterization was conducted using field emission scanning electron microscope fitted with scanning transmission electron detector, atomic force microscope and X-ray diffractometer. Nanoindentation hardness, elastic modulus, adhesion, coefficients of friction and wear rates were determined for both dc and pulse electrodeposits. Experimental results indicate that pulse electrodeposition produced finer Ni grains compared to dc plating. Size of Ni grains increased with deposition. Both dc and pulse deposition resulted in grain growth in preferred (2 0 0) orientation. However, presence of Ni (1 1 1) grains increased in deposits produced by pulse deposition. Pulse plated Ni exhibited higher hardness, creep and coefficient of friction and lower modulus of elasticity compared to dc plated Ni.

SILVER RECYCLING FROM PHOTO-PROCESSING WASTE USING ELECTRODEPOSITION METHOD

Directory of Open Access Journals (Sweden)

Mochammad Feri Hadiyanto

2010-06-01

Full Text Available Silver electrodeposition of photo-processing waste and without addition of KCN 1,0 M has been studied for silver recycling. Photo procesing waste containing silver in form of [Ag(S2O32]3- was electrolysed at constant potential and faradic efficiency was determined at various of electrolysis times. Electrolysis of 100 mL photo processing waste without addition of KCN 1,0 M was carried out at constant potential 1.20 Volt, while electrolysis 100 mL photo procesing waste with addition of 10 mL KCN 1,0 M electrolysis was done at 1.30 Volt.The results showed that for silver electrodeposition from photo processing waste with addition of KCN 1,0 M was more favorable with faradic efficiency respectively were 93,16; 87,02; 74,74 and 78,35% for 30; 60; 90 and 120 minutes of electrolysis.   Keywords: Silver extraction, electrodeposition, photo-processing waste

Uniform deposition of water-soluble CdS quantum dots on TiO2 nanotube arrays by cyclic voltammetric electrodeposition: Effectively prevent aggregation and enhance visible-light photocatalytic activity

International Nuclear Information System (INIS)

Zhang, Xiaojiao; Lin, Shiwei; Liao, Jianjun; Pan, Nengqian; Li, Danhong; Cao, Xiankun; Li, Jianbao

2013-01-01

Highlights: • Water-soluble CdS QDs were deposited on the TNTAs by DC electrodeposition, CV electrodeposition, and SILAR. • The CV method could effectively prevent the aggregation and uniformly deposit CdS QDs onto the TNTAs. • The CTAB/CdS/TNTAs prepared by the CV method exhibited superior photoelectrical properties and photocatalytic activity. -- Abstract: Water-soluble CdS quantum dots (QDs) covered with cationic surfactant-cetyltrimethylammonium bromide (CTAB) were deposited on the highly ordered TiO 2 nanotube arrays (TNTAs) by various methods, such as direct current (DC) electrodeposition, cyclic voltammetric (CV) electrodeposition, and successive ionic layer adsorption reaction (SILAR). The morphology measurements show that CTAB capping could well control the QD size and the CV method could effectively prevent the nanoparticle aggregation and uniformly deposit QDs onto TNTAs. Among all the deposition methods studied, the sample prepared by the CV method possesses superior photoelectrical properties and photocatalytic activity. A maximum photoconversion efficiency of 2.81% is achieved for the CdS/TNTAs prepared by CV electrodeposition, which exhibits about 17 times enhancement over the efficiency of the sample prepared by DC electrodeposition. And the photocatalytic degradation of methyl orange under visible-light irradiation demonstrates that the rate constant of the sample prepared by the CV method is almost seven times of that of the untreated TNTAs. Moreover, the underlying mechanism for the improving properties has been discussed

Al2O3 coating fabricated on titanium by cathodic microarc electrodeposition

International Nuclear Information System (INIS)

Jin Qian; Xue Wenbin; Li Xijin; Zhu Qingzhen; Wu Xiaoling

2009-01-01

A Al 2 O 3 coating was prepared on titanium substrate by cathodic microarc electrodeposition method in Al(NO 3 ) 3 ethanol solution. The coating thickness was about 80 μm when a 400 V cathodic potential was applied. The morphology and phase constituent of the Al 2 O 3 coating were investigated by scanning electron microscope (SEM) and X-ray diffraction (XRD). The isothermal oxidation at 700 deg. C and electrochemical corrosion behavior of the coated titanium were analyzed. The coating was composed of γ-Al 2 O 3 and little α-Al 2 O 3 phases. The oxidation resistance of the titanium subjected to cathodic microarc treatment was obviously improved. The polarization test indicated that the coated titanium has better corrosion resistance.

Study of the formation process and the characteristics of tantalum layers electrodeposited on Nitinol plates in the 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid

International Nuclear Information System (INIS)

Maho, A.; Delhalle, J.; Mekhalif, Z.

2013-01-01

Highlights: ► Tantalum electrodeposition on Nitinol plates in the [BMP]Tf 2 N ionic liquid at room temperature. ► Generation of intrinsically nanostructured porous tantalum layers in “soft” cathodic current conditions. ► Important impact of substrate nature, working solution composition and electrodeposition duration. ► Primary assessment of surface corrosion resistance and bioactivity. -- Abstract: Thanks to excellent mechanical and biochemical properties, the nickel–titanium shape memory alloy (Nitinol) constitutes an increasingly praised platform material in dental, cardiovascular and orthopedic biomedical devices. In order to strengthen their protective abilities toward corrosion, to reinforce their biocompatibility and to confer them specific osseointegrative capacities, Nitinol plates are covered with a thin tantalum layer by electrodeposition in the 1-butyl-1-methylpyrrolidinium bis(trifluoromethylsulfonyl)imide ionic liquid. XPS and SEM/EDX analyses highlight the chemical and morphological characteristics of the deposits: notably, these present an intrinsic dimpled nanometric structuration which is particularly remarkable considering the “soft” experimental conditions and very interesting for fundamental and applied bioactive perspectives. The present study investigates the specific and synergic effects of the Ni occurrence on the surface of the Nitinol substrates, the presence of fluorine species in the working bath, and the electrodeposition duration on the resulting formation process, morphology and chemical composition of the tantalum coating. Finally, samples are submitted to electrochemical characterizations and in vitro hydroxyapatite growth tests for a primary assessment of their corrosion resistance and osseoinductive features

Microstructure and corrosion behavior of electrodeposited nano-crystalline nickel coating on AZ91 Mg alloy

Energy Technology Data Exchange (ETDEWEB)

Zarebidaki, Arman, E-mail: arman.zare@iauyazd.ac.ir; Mahmoudikohani, Hassan, E-mail: hassanmahmoudi.k@gmail.com; Aboutalebi, Mohammad-Reza

2014-12-05

Highlights: • Activation, zincating, and Cu electrodeposition were used as pretreatment processes for electrodeposition of nickel coatings. • Nano-crystalline nickel coatings were successfully electrodeposited onto the AZ91 Mg alloys. • Effect of nickel electrodeposited coating on the corrosion resistance of AZ91 Mg alloy has been studied. - Abstract: In order to enhance the corrosion resistance, nickel coating was electrodeposited onto AZ91 Mg alloy. Activation, zincating, and Cu electrodeposition used as pretreatment processes for better adhesion and corrosion performance of the nickel over layer. The corrosion properties of the AZ91 Mg alloy, nickel electroplated AZ91 Mg alloy, and pure nickel was assessed via polarization and electrochemical impedance spectroscopy (EIS) methods in 3.5 wt% NaCl solution. Moreover, the structure of the coating was investigated by means of X-ray diffraction, whereas specimen’s morphology and elemental composition were analyzed using scanning electron microscope (SEM) equipped with energy dispersive spectrometer (EDS). Measurements revealed that the coating has a nano-crystalline structure with the grain size of 95 nm. Corrosion results showed superior corrosion resistance for the coated AZ91 Mg alloy as the corrosion current density decreased from 2.5 × 10{sup −4} A cm{sup −2}, for the uncoated sample, to 1.5 × 10{sup −5} A cm{sup −2}, for coated specimen and the corrosion potential increased from −1.55 V to −0.98 V (vs. Ag/AgCl) at the same condition.

Nanocrystalline Ni-Co Alloy Synthesis by High Speed Electrodeposition

Directory of Open Access Journals (Sweden)

Jamaliah Idris

2013-01-01

Full Text Available Electrodeposition of nanocrystals is economically and technologically viable production path for the synthesis of pure metals and alloys both in coatings and bulk form. The study presents nanocrystalline Ni-Co alloy synthesis by high speed electrodeposition. Nanocrystalline Ni-Co alloys coatings were prepared by direct current (DC and deposited directly on steel and aluminum substrates without any pretreatment, using high speed electrodeposition method. The influence of the electrolysis parameters, such as cathodic current density and temperature at constant pH, on electrodeposition and microstructure of Ni-Co alloys were examined. A homogeneous surface morphology was obtained at all current densities of the plated samples, and it was evident that the current density and temperature affect the coating thickness of Ni-Co alloy coatings.

Lead dioxide electrodes for high potential anodic processes

OpenAIRE

A. B. VELICHENKO; ROSSANO AMADELLI

2001-01-01

Doping of PbO2 by cations (Fe3+, Co2+ and Ni2+), by F- and by cations and F- simultaneously is discussed as a way of improving the stability and electrochemical activity in processes occurring at high potentials. Doping allows the control of the amount of structural water in an oxide. Radiotracer experiments showed that high electrodeposition current densities favour the segregation of incorporated tritium (protons) at the surface. On the other hand, fluorine doping results in a marked decrea...

Controllable wettability and morphology of electrodeposited surfaces on zinc substrates

Energy Technology Data Exchange (ETDEWEB)

Zhang, Binyan; Lu, Shixiang, E-mail: shixianglu@bit.edu.cn; Xu, Wenguo, E-mail: wenguoxu60@bit.edu.cn; Cheng, Yuanyuan

2016-01-01

Graphical abstract: Superhydrophobic surfaces combining hierarchical micro/nanostructures were fabricated on zinc substrates by etching, electrodeposition of ZnO coatings and annealing. Such superhydrophobic surfaces offer possibilities for chemical, biological, electronic and microfluidic applications. - Highlights: • Superhydrophobic surface was fabricated via electrodeposition of ZnO and annealing. • The ZnO hierarchical micro/nanostructures contribute to the surface superhydrophobicity. • Surface wettability and morphology can be controlled by varying process conditions. • The anti-icing properties and reversible wetting behaviors of the ZnO coatings were studied. - Abstract: Superhydrophobic surfaces combining hierarchical micro/nanostructures were fabricated on zinc substrates by etching in hydrochloric acid solution, electrodeposition of ZnO coatings and subsequent thermal annealing. The optimal coatings were electrodeposited at −1.25 V for 900 s on the etched zinc substrates and then annealed at 200 °C for 60 min, which could achieve a maximum water contact angle of 170 ± 2° and an ultra-low sliding angle of approximately 0°. By conducting SEM and water CA analysis, we found that the morphology and wettability of prepared samples were controllable by the fabrication process. Interestingly, even without any additional modification, the samples prepared under different electrodeposition conditions (including Zn(CH{sub 3}COO){sub 2} concentration from 5 mM to 40 mM and deposition time from 300 s to 1500 s) exhibited superhydrophobic character. The influences of the Zn(CH{sub 3}COO){sub 2} concentration, deposition time, annealing temperature and annealing time on the wetting behaviors were also discussed in detail. Such superhydrophobic surfaces possess long-term stability, and good corrosion resistance as well as self-cleaning ability. In addition, the anti-icing properties of the ZnO films were investigated. These surfaces could be rapidly and

Controllable wettability and morphology of electrodeposited surfaces on zinc substrates

International Nuclear Information System (INIS)

Zhang, Binyan; Lu, Shixiang; Xu, Wenguo; Cheng, Yuanyuan

2016-01-01

Graphical abstract: Superhydrophobic surfaces combining hierarchical micro/nanostructures were fabricated on zinc substrates by etching, electrodeposition of ZnO coatings and annealing. Such superhydrophobic surfaces offer possibilities for chemical, biological, electronic and microfluidic applications. - Highlights: • Superhydrophobic surface was fabricated via electrodeposition of ZnO and annealing. • The ZnO hierarchical micro/nanostructures contribute to the surface superhydrophobicity. • Surface wettability and morphology can be controlled by varying process conditions. • The anti-icing properties and reversible wetting behaviors of the ZnO coatings were studied. - Abstract: Superhydrophobic surfaces combining hierarchical micro/nanostructures were fabricated on zinc substrates by etching in hydrochloric acid solution, electrodeposition of ZnO coatings and subsequent thermal annealing. The optimal coatings were electrodeposited at −1.25 V for 900 s on the etched zinc substrates and then annealed at 200 °C for 60 min, which could achieve a maximum water contact angle of 170 ± 2° and an ultra-low sliding angle of approximately 0°. By conducting SEM and water CA analysis, we found that the morphology and wettability of prepared samples were controllable by the fabrication process. Interestingly, even without any additional modification, the samples prepared under different electrodeposition conditions (including Zn(CH_3COO)_2 concentration from 5 mM to 40 mM and deposition time from 300 s to 1500 s) exhibited superhydrophobic character. The influences of the Zn(CH_3COO)_2 concentration, deposition time, annealing temperature and annealing time on the wetting behaviors were also discussed in detail. Such superhydrophobic surfaces possess long-term stability, and good corrosion resistance as well as self-cleaning ability. In addition, the anti-icing properties of the ZnO films were investigated. These surfaces could be rapidly and reversibly switched

Long Silver Nanowires Synthesis by Pulsed Electrodeposition

Directory of Open Access Journals (Sweden)

M.R. Batevandi

2015-09-01

Full Text Available Silver nanowires were pulse electrodeposited into nanopore anodic alumina oxide templates. The effects of continuous and pulse electrodeposition waveform on the microstructure properties of the nanowire arrays were studied. It is seen that the microstructure of nanowire is depend to pulse condition. The off time duration of pulse waveform enables to control the growth direction of Ag nanowires.

Electrodeposition of Asphaltenes. 2. Effect of Resins and Additives

DEFF Research Database (Denmark)

Khvostichenko, Daria S; Andersen, Simon Ivar

2010-01-01

Electrodeposition of asphaltenes from oil/heptane, asphaltene/heptane, and asphaltene/heptane/additive mixtures has been investigated. Toluene, native petroleum resins, and a synthetic asphaltene dispersant, p-nonylphenol, were used as additives. The addition of these components led to partial...... dissolution of asphaltenes in heptane. The charge of asphaltenic particles was found to be negative in oil/heptane mixtures and positive in asphaltene/heptane mixtures. In asphaltene/heptane/toluene systems, the charge of the deposit varied from positive to neutral to negative, depending upon the method...

Liquid Membrane System for Extraction and Electrodeposition of Lead(II During Electrodialysis

Directory of Open Access Journals (Sweden)

Sadyrbaeva Tatiana

2017-05-01

Full Text Available A novel method for lead(II removal from aqueous acidic solutions is presented. The method involves electrodialysis through bulk liquid membranes accompanied by electrodeposition of metal from the cathodic solution. Solutions of di(2-ethylhexylphosphoric acid with admixtures of tri-n-octylamine in 1,2-dichloroethane were used as the liquid membranes. The effects of the main electrodialysis parameters as well as of the composition of the liquid membranes and aqueous solutions on the lead(II transport rate are studied. The optimal conditions are determined. A possibility of effective single-stage transfer of lead(II through the liquid membrane into dilute solutions of perchloric, nitric and acetic acids is demonstrated. Dense and adherent lead electrodeposits are obtained from perchloric acid solutions. Maximum extraction degree of 93 % and electrodeposition degree of ~60 % are obtained during 5 h of electrodialysis.

Electrodeposition of germanium from supercritical fluids.

Science.gov (United States)

Ke, Jie; Bartlett, Philip N; Cook, David; Easun, Timothy L; George, Michael W; Levason, William; Reid, Gillian; Smith, David; Su, Wenta; Zhang, Wenjian

2012-01-28

Several Ge(II) and Ge(IV) compounds were investigated as possible reagents for the electrodeposition of Ge from liquid CH(3)CN and CH(2)F(2) and supercritical CO(2) containing as a co-solvent CH(3)CN (scCO(2)) and supercritical CH(2)F(2) (scCH(2)F(2)). For Ge(II) reagents the most promising results were obtained using [NBu(n)(4)][GeCl(3)]. However the reproducibility was poor and the reduction currents were significantly less than the estimated mass transport limited values. Deposition of Ge containing films was possible at high cathodic potential from [NBu(n)(4)][GeCl(3)] in liquid CH(3)CN and supercritical CO(2) containing CH(3)CN but in all cases they were heavily contaminated by C, O, F and Cl. Much more promising results were obtained using GeCl(4) in liquid CH(2)F(2) and supercritical CH(2)F(2). In this case the reduction currents were consistent with mass transport limited reduction and bulk electrodeposition produced amorphous films of Ge. Characterisation by XPS showed the presence of low levels of O, F and C, XPS confirmed the presence of Ge together with germanium oxides, and Raman spectroscopy showed that the as deposited amorphous Ge could be crystallised by the laser used in obtaining the Raman measurements.

Method of recovering phosphoric acid type decontaminating electrolytes by electrodeposition

International Nuclear Information System (INIS)

Sasaki, Takashi; Wada, Koichi; Kobayashi, Toshio.

1985-01-01

Purpose: To recoving phosphoric acid type highly concentrated decontaminating liquid used for the electrolytic decontamination of contaminated equipments, components, etc in nuclear power plants or the like through electrodeposition by diaphragm electrolysis. Method: Before supplying phosphoric acid decontaminating liquid at high concentration used in the electrolytic decontaminating step to an electrodeposition recovering tank, phosphoric acid in the decontaminating electrolyte is extracted with solvents and decomposed liquid extracts (electrolyte reduced with the phosphoric acid component) are supplied to the cathode chamber of the electrodeposition recovering tank, where phosphoric acid is back-extracted with water from the solvents after extraction of phosphoric acid. Then, the back-extracted liquids (aqueous phosphoric acid solution scarcely containing metal ions) are sent to the anode chamber of the electrodeposition recovering tank. Metal ions in the liquid are captured by electrodeposition in the cathode chamber, as well as phosphoric acid in the liquids is concentrated to the initial concentration of the electrolyte in the anode chamber for reuse as the decontaminating electrolyte. As the phosphoric acid extracting agent used in the electrodeposition recovering step for the decontaminating electrolyte, water-insoluble and non-combustible tributyl phosphate (TBP) is most effective. (Horiuchi, T.)

Investigation of Gamma and Neutron Shielding Parameters for Borate Glasses Containing NiO and PbO

OpenAIRE

Singh, Vishwanath P.; Badiger, N. M.

2014-01-01

The mass attenuation coefficients, μ/ρ, half-value layer, HVL, tenth-value layer, TVL, effective atomic numbers, ZPIeff, and effective electron densities, Ne,eff, of borate glass sample systems of (100-x-y) Na2B4O7 : xPbO : yNiO (where x and y=0, 2, 4, 6, 8, and 10 weight percentage) containing PbO and NiO, with potential gamma ray and neutron shielding applications, have been investigated. The gamma ray interaction parameters, μ/ρ, HVL, TVL, ZPIeff, and Ne,eff, were computed for photon energ...

Thin coating thickness determination using radioisotope-excited x-ray fluorescence spectrometry

International Nuclear Information System (INIS)

Del Castillo, Lorena A.; Calix, Virginia S.

2001-01-01

Three different approaches on thin coating thickness determination using a radioisotope-excited x-ray fluorescence spectrometry were demonstrated and results were compared. A standard of thin layer of gold (Au) on a nickel (Ni) substrate from the US National Bureau of Standards (with a nominal thickness of 0.300505 microns of at least 99.9% Au electrodeposited over 2 nils of Ni) on low carbon steel (1010) was analyzed using a Cd 109-excited XRF system. Au thickness computations were done using the (a) thin standard approach, (b) thick standard approach, and (c) x-ray absorption method (ASTM A754-79 1982). These three methods yielded results within the limit set by the American Society for Testing Materials (ASTM), which is +/-3%. Of the three methods, the thick standard yielded the best result with 0.124% error. (Author)

Facile Growth of Cu2ZnSnS4 Thin-Film by One-Step Pulsed Hybrid Electrophoretic and Electroplating Deposition

Science.gov (United States)

Tsai, Hung-Wei; Chen, Chia-Wei; Thomas, Stuart R.; Hsu, Cheng-Hung; Tsai, Wen-Chi; Chen, Yu-Ze; Wang, Yi-Chung; Wang, Zhiming M.; Hong, Hwen-Fen; Chueh, Yu-Lun

2016-01-01

The use of costly and rare metals such as indium and gallium in Cu(In,Ga)Se2 (CIGS) based solar cells has motivated research into the use of Cu2ZnSnS4 (CZTS) as a suitable replacement due to its non-toxicity, abundance of compositional elements and excellent optical properties (1.5 eV direct band gap and absorption coefficient of ~104 cm−1). In this study, we demonstrate a one-step pulsed hybrid electrodeposition method (PHED), which combines electrophoretic and electroplating deposition to deposit uniform CZTS thin-films. Through careful analysis and optimization, we are able to demonstrate CZTS solar cells with the VOC, JSC, FF and η of 350 mV, 3.90 mA/cm2, 0.43 and 0.59%, respectively. PMID:26902556

Two-step electrodeposition to fabricate the p-n heterojunction of a Cu2O/BiVO4 photoanode for the enhancement of photoelectrochemical water splitting.

Science.gov (United States)

Bai, Shouli; Liu, Jingchao; Cui, Meng; Luo, Ruixian; He, Jing; Chen, Aifan

2018-05-15

A Cu2O/BiVO4 p-n heterojunction based photoanode in photoelectrochemical (PEC) water splitting is fabricated by a two-step electrodeposition method on an FTO substrate followed by annealing treatment. The structures and properties of the samples are characterized by XRD, FESEM, HRTEM, XPS and UV-visible spectra. The photoelectrochemical activity of the photoanode in water oxidation has been investigated and measured in a three electrode quartz cell system; the obtained maximum photocurrent density of 1.72 mA cm-2 at 1.23 V vs. RHE is 4.5 times higher than that of pristine BiVO4 thin films (∼0.38 mA cm-2). The heterojunction based photoanode also exhibits a tremendous cathodic shift of the onset potential (∼420 mV) and enhancement in the IPCE value by more than 4-fold. The enhanced photoelectrochemical properties of the Cu2O/BiVO4 photoelectrode are attributed to the efficient separation of the photoexcited electron-hole pairs caused by the inner electronic field (IEF) of the p-n heterojunction.

Electrodeposition of Manganese-Nickel Oxide Films on a Graphite Sheet for Electrochemical Capacitor Applications

Directory of Open Access Journals (Sweden)

Hae-Min Lee

2014-01-01

Full Text Available Manganese-nickel (Mn-Ni oxide films were electrodeposited on a graphite sheet in a bath consisting of manganese acetate and nickel chloride, and the structural, morphological, and electrochemical properties of these films were investigated. The electrodeposited Mn-Ni oxide films had porous structures covered with nanofibers. The X-ray diffractometer pattern revealed the presence of separate manganese oxide (g-MnO2 and nickel oxide (NiO in the films. The electrodeposited Mn-Ni oxide electrode exhibited a specific capacitance of 424 F/g in Na2SO4 electrolyte. This electrode maintained 86% of its initial specific capacitance over 2000 cycles of the charge-discharge operation, showing good cycling stability.

Silicon electrodeposition from chloride-fluoride melts containing K2SiF6 and SiO2

Directory of Open Access Journals (Sweden)

Zhuk Sergey I.

2017-01-01

Full Text Available Silicon electrodeposition on glassy carbon from the KF-KCl-K2SiF6, KF-KCl-K2SiF6-KOH and KF-KCl-K2SiF6-SiO2 melts was studied by the cyclic voltammetry. Тhe electroreduction of Si(IV to metallic Si was observed as a single 4-electron wave under all considered conditions. The reactions of cathode reduction of silicon from fluoride and oxyfluoride complexes were suggested. It was shown that the process can be controlled by the preliminary transformation of SiO44- to SiF62- and SiOxFyz-. The influence of the current density on structure and morphology of silicon deposits obtained during galvanostatic electrolysis of the KF-KCl-K2SiF6-SiO2 melt was studied.

Effect of triethanolamine and heliotropin on cathodic polarization of weakly acidic baths and properties of Sn-Ag-Cu alloy electrodeposits

International Nuclear Information System (INIS)

Zhang Jinqiu; An Maozhong; Chang Limin; Liu Guiyuan

2008-01-01

The effect of triethanolamine (TEA) and heliotropin (HT) on the cathodic polarization of weakly acidic baths and the properties of Sn-Ag-Cu alloy electrodeposits were investigated. Lead-free Sn-Ag-Cu solder alloy were electrodeposited in weakly acidic baths (pH 5.5) containing Sn(CH 3 SO 3 ) 2 , AgI, Cu(CH 3 SO 3 ) 2 , K 4 P 2 O 7 , KI, hydroquinone, TEA, HT and methylsulfonic acid (MSA). The cathodic polarization of baths and the properties of electrodeposits were evaluated by Liner sweep voltammetry (LSV), scanning electron microscopy (SEM), X-ray fluorescence (XRF), X-ray diffraction (XRD), Fourier transform infrared spectrometer (FT-IR) and X-ray photoelectron spectroscopy (XPS). The results indicate that HT is a main brightening agent that increases the cathodic polarization of baths and refines the grains of electrodeposits; TEA is a complexing agent for copper ions and a brightening promoter that decreases the cathodic polarization of baths and densifies the electrodeposits. The bright, compact, and smooth Sn-Ag-Cu alloy electrodeposits contain 88-95 wt% tin, 5-10 wt% silver and 0.5-2 wt% copper. Organic compounds used in the baths neither adsorb on the electrodeposits surfaces nor are included in the electrodeposits. It can be therefore concluded that the use of both TEA and HT is better than that of them either in the process of electroplating bright Sn-Ag-Cu alloy

Effects of melt-temperature on limiting current density in Al electrodeposition and morphology of Al electrodeposits obtained from ambient temperature type molten salt; Joongata yoyuen kara no denki aluminium mekki no genkai denryu mitsudo oyobi denseki keitai ni oyobosu mekki ekion no eikyo

Energy Technology Data Exchange (ETDEWEB)

Shimizu, T.; Tatano, M.; Uchida, Y. [Nisshin Steel Co. Ltd., Tokyo (Japan)

1996-03-31

Some of more important electrolytic solutions for Al electrodeposition are organic solvents, high-temperature type molten salts and low-temperature type molten salts having a melting point of 30{degree}C or lower, such as ethylmethylimidazolium chloride (EMIC). This study uses a molten salt of AlCl3-EMIC as the low-temperature type solution for high-speed electrodeposition. Discussed herein are the effects of melt temperature on limiting current density in Al electrodeposition and Al electrodeposit morphology. Limiting current density increases as melt temperature increases at any AlCl3 concentration used in this study. The AlCl3 concentration that gives the maximum limiting current density shifts from 64 to 67mol% at a melt temperature of 120{degree}C. A dense, smooth Al electrodeposited film results at a melt temperature of 100{degree}C or lower, but the electrodeposited grains become coarser as melt temperature increases. Melt temperature can be increased to 140{degree}C to secure a smooth electrodeposited film, showing possibility of 2 times faster electrodeposition than the conventional one. 21 refs., 12 figs., 1 tab.

Electrodeposited porous and amorphous copper oxide film for application in supercapacitor

Energy Technology Data Exchange (ETDEWEB)

Patake, V.D. [Thin Film Physics Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, (M.S.) (India); Joshi, S.S. [Clean Energy Research Center, Korea Institute of Science and Technology, Cheongryang, Seoul 130-650 (Korea, Republic of); Lokhande, C.D. [Thin Film Physics Laboratory, Department of Physics, Shivaji University, Kolhapur 416004, (M.S.) (India); Clean Energy Research Center, Korea Institute of Science and Technology, Cheongryang, Seoul 130-650 (Korea, Republic of)], E-mail: l_chandrakant@yahoo.com; Joo, Oh-Shim [Clean Energy Research Center, Korea Institute of Science and Technology, Cheongryang, Seoul 130-650 (Korea, Republic of)], E-mail: joocat@kist.rre.kr

2009-03-15

In present study, the porous amorphous copper oxide thin films have been deposited from alkaline sulphate bath. The cathodic electrodeposition method was employed to deposit copper oxide film at room temperature on stainless steel substrate. Their structural and surface morphological properties were investigated by means of X-ray diffraction (XRD) and scanning electron micrograph (SEM), respectively. To propose this as a new material for possible application in the supercapacitor, its electrochemical properties have been studied in aqueous 1 M Na{sub 2}SO{sub 4} electrolyte using cyclic voltammetry. The structural analysis from XRD pattern showed the formation of amorphous copper oxide film on the substrate. The surface morphological studies from scanning electron micrographs revealed the formation of porous cauliflower-like copper oxide film. The cyclic voltammetric curves showed symmetric nature and increase in capacitance with increase in film thickness. The maximum specific capacitance of 36 F g{sup -1} was exhibited for the 0.6959 mg cm{sup -2} film thickness. This shows that low-cost copper oxide electrode will be a potential application in supercapacitor.

Syntheses and characterizations of secondary Pb-O bonding supported Pb(II)-sulfonate complexes

Science.gov (United States)

Huang, Guo-Zhen; Zou, Xin; Zhu, Zhi-Biao; Deng, Zhao-Peng; Huo, Li-Hua; Gao, Shan

2018-06-01

The reaction of Pb(II) salts and mono- or disulfonates leads to the formation of eight new Pb(II)-mono/disulfonate complexes, [Pb(L1)(H2O)]2 (1), [Pb4(L2)2(AcO)2]n·5nH2O (2), [Pb(L3)(H2O)]2 (3), [Pb(HL4)(H2O)2]n·nH2O (4), [Pb(HL5)(H2O)2]n·2nH2O (5), [Pb(H2L6)(H2O)]n·nDMF·2nH2O (6), [Pb2(H3L7)4(H2O)6]·2H2O (7) and [Pb(H2L7)(H2O)]n·nH2O (8) (H2L1= 2-hydroxy-5-methyl-benzenesulfonic acid, H3L2= 2-hydroxyl-5-methyl- 1,3-benzenedisulfonic acid, H2L3= 2-hydroxy-5-nitro-benzenesulfonic acid, H3L4= 2-hydroxyl-5-bromo-1,3- benzenedisulfonic acid, H3L5= 2-hydroxyl-5-carboxyl-benzenesulfonic acid, H4L6= 2,5-dihydroxyl-3-carboxyl- benzenesulfonic acid, H4L7= 2,4-dihydroxyl-5-carboxyl-benzenesulfonic acid, DMF = N,N'-dimethyl-formamide, AcO- = acetate), which have been characterized by elemental analysis, IR, TG, PL, powder and single-crystal X-ray diffraction. In view of the primary Pb-O bonds, these eight complexes exhibit diverse dinuclear (1, 3 and 7), helical chain (4), wave-like chain (5), linear chain (6), zigzag chain (8) and layer structure (2), in which the Pb(II) cations present different hemi-directed geometries. Taking the secondary Pb-O bonds into account, chain structure for complex 7, layer motifs for complexes 1 and 3-6, as well as 3-D framework for complex 8 are observed with Pb(II) cations showing more intricate holo-directed geometries. The various coordination modes of these seven different mono/disulfonate anions are responsible for the formation of these multiple structures. Furthermore, the introduction of hydroxyl and carboxyl groups increases the coordination ability of sulfonate to the p-block metal cation. Luminescent analyses indicate that complex 7 presents purple emission at 395 nm at room temperature.

Electro-deposition metallic tungsten coatings in a Na{sub 2}WO{sub 4}-WO{sub 3} melt on copper based alloy substrate

Energy Technology Data Exchange (ETDEWEB)

Liu, Y.H., E-mail: dreamerhong77@126.com [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China); Zhang, Y.C.; Liu, Q.Z.; Li, X.L.; Jiang, F. [School of Materials Science and Engineering, University of Science and Technology Beijing, 30 Xueyuan Road, Haidian District, Beijing 100083 (China)

2012-11-15

Highlights: Black-Right-Pointing-Pointer The tungsten coating (>1 mm) was obtained by electro-deposition method in molten salt. Black-Right-Pointing-Pointer Different thickness tungsten coatings were obtained by using different durations. Black-Right-Pointing-Pointer Good performance of coating was obtained when pulse parameters were modulated. - Abstract: The tungsten coating was prepared by electro-deposition technique on copper alloy substrate in a Na{sub 2}WO{sub 4}-WO{sub 3} melt. The coating's surface and cross-section morphologies as well as its impurities were investigated by XPS, SEM and line analysis. Various plating durations were investigated in order to obtain an optimal coating's thickness. The results demonstrated that the electro-deposited coating was compact, voidless, crackless and free from impurities. The tungsten coating's maximum Vickers hardness was measured to be 520 HV. The tungsten coating's minimum oxygen content was determined to be 0.018 wt%. Its maximum thickness was measured to be 1043.67 {mu}m when the duration of electrolysis was set to 100 h. The result of this study has demonstrated the feasibility of having thicker tungsten coatings on copper alloy substrates. These electrodeposited tungsten coatings can be potentially implemented as reliable armour for the medium heat flux plasma facing component (PFC).

Morphology-controlled electrodeposition of Cu2O microcrystalline particle films for application in photocatalysis under sunlight

International Nuclear Information System (INIS)

Wu, Guodong; Zhai, Wei; Sun, Fengqiang; Chen, Wei; Pan, Zizhao; Li, Weishan

2012-01-01

Graphical abstract: Display Omitted Highlights: ► PEG was used to electro-deposit Cu 2 O microcrystalline particle films. ► Morphologies of Cu 2 O microcrystals could be controlled by the amount of PEG. ► The films showed regularly varied photocatalytic activities under sunlight. ► The films could be recycled and showed stable activities. -- Abstract: Morphology-controlled Cu 2 O microcrystalline particle films had been successfully electrodeposited on tin-doped indium oxide glass substrates in CuSO 4 solutions containing different amounts of polyethylene glycol (PEG) additives. With an increase of PEG, microcrystals gradually changed from irregular shapes to cubes, octahedrons, and spherical shapes. Sizes increasingly became smaller with an increase of PEG under the same deposition time. These films had been first used as recyclable photocatalysts and showed excellent and photocatalytic activities in photodegradation of methylene blue (MB) under sunlight. Activities were regularly varied relative to the morphologies of films controlled by the amount of PEG and could be further enhanced by adding a little amount of hydrogen peroxide in the MB solution. The method for controllable preparation of Cu 2 O microcrystals with photocatalytic activities was simple and inexpensive. The as-prepared particle films could also be used in photodegradation of many other pollutants under sunlight.

A study on molybdenum sulphoselenide (MoSxSe2−x, 0 ≤ x ≤ 2) thin films: Growth from solution and its properties

International Nuclear Information System (INIS)

Anand, T. Joseph Sahaya; Shariza, S.

2012-01-01

Highlights: ► Effect of deposition time on the properties of molybdenum chalcogenide thin films. ► First time to compare the study of binary and ternary molybdenum chalcogenides. ► No previous report on ternary molybdenum sulphoselenide by electrodeposition. ► Semiconducting parameters by CV analysis promising to be good solar cell material. - Abstract: Thin films of molybdenum sulphoselenide, MoS x Se 2−x , (0 ≤ x ≤ 2) have been electrosynthesized on indium-tin-oxide (ITO)-coated glass and stainless steel substrates. The films were characterized for their structural, morphological and compositional characteristics. Their optical and semiconducting parameters were also analysed in order to determine the suitability of the thin films for photoelectrochemical (PEC)/solar cell applications. Structural analysis via X-ray diffraction (XRD) analysis reveals that the films are polycrystalline in nature. Scanning electron microscope (SEM) studies reveals the films were adherent to the substrate with uniform in nature which also confirmed by Transmission electron microscope (TEM). Compositional analysis via energy dispersive X-ray (EDX) technique confirms the presence of Mo, S and Se elements in the films. The optical studies show that the films are of direct bandgap. Results on the semiconductor parameters analysis of the films showed that the nature of the Mott–Schottky plots indicates that the films obtained are of n-type material. For all films, the semiconductor parameter values come in the better range of other transition metal chalcogenides which has proven that MoSSe thin films are capable as solar/PEC cell materials.

Shear induced phase transition in PbO under high pressure

International Nuclear Information System (INIS)

Giefers, Hubertus; Porsch, Felix

2007-01-01

We have studied the structural behavior of lead monoxide (PbO) as a function of pressure via angular dispersive X-ray diffraction employing two different pressure transmitting media that were quasi-hydrostatic (N 2 ) and non-hydrostatic (MgO), respectively. Besides litharge (α-PbO) and massicot (β-PbO), which are both stable at ambient pressure, there is an orthorhombic γ-PbO phase which appears upon application of pressure to α-PbO. We have found that the orthorhombic γ-PbO phase is favored by shear stress under non-hydrostatic conditions. α-PbO shows strong anisotropy in compressibility. The a-axis is rather incompressible with a linear stiffness coefficient of K a0 =540(30) GPa whereas the c-axis stiffness is K c0 =25(1) GPa. The bulk modulus of α-PbO is K 0 =23.1(3) GPa and its derivative K 0 ' =7.0(3)

Stable lithium electrodeposition in liquid and nanoporous solid electrolytes

KAUST Repository

Lu, Yingying; Tu, Zhengyuan; Archer, Lynden A.

2014-01-01

of these metals and their inability to form uniform electrodeposits on surfaces with inevitable defects. We report on electrodeposition of lithium in simple liquid electrolytes and in nanoporous solids infused with liquid electrolytes. We find that simple liquid

Niobium electrodeposition from molten fluorides

International Nuclear Information System (INIS)

Sartori, A.F.

1987-01-01

Niobium electrodeposition from molten alkali fluorides has been studied aiming the application of this technic to the processes of electrorefining and galvanotechnic of this metal. The effects of current density, temperature, niobium concentration in the bath, electrolysis time, substrate nature, ratio between anodic and cathodic areas, electrodes separation and the purity of anodes were investigated in relation to the cathodic current efficiency, electrorefining, electroplating and properties of the deposit and the electrolytic solution. The work also gives the results of the conctruction and operation of a pilot plant for refractory metals electrodeposition and shows the electrorefining and electroplating compared to those obtained at the laboratory scale. (author) [pt

Embedded vertically aligned cadmium telluride nanorod arrays grown by one-step electrodeposition for enhanced energy conversion efficiency in three-dimensional nanostructured solar cells.

Science.gov (United States)

Wang, Jun; Liu, Shurong; Mu, Yannan; Liu, Li; A, Runa; Yang, Jiandong; Zhu, Guijie; Meng, Xianwei; Fu, Wuyou; Yang, Haibin

2017-11-01

Vertically aligned CdTe nanorods (NRs) arrays are successfully grown by a simple one-step and template-free electrodeposition method, and then embedded in the CdS window layer to form a novel three-dimensional (3D) heterostructure on flexible substrates. The parameters of electrodeposition such as deposition potential and pH of the solution are varied to analyze their important role in the formation of high quality CdTe NRs arrays. The photovoltaic conversion efficiency of the solar cell based on the 3D heterojunction structure is studied in detail. In comparison with the standard planar heterojunction solar cell, the 3D heterojunction solar cell exhibits better photovoltaic performance, which can be attributed to its enhanced optical absorption ability, increased heterojunction area and improved charge carrier transport. The better photoelectric property of the 3D heterojunction solar cell suggests great application potential in thin film solar cells, and the simple electrodeposition process represents a promising technique for large-scale fabrication of other nanostructured solar energy conversion devices. Copyright © 2017 Elsevier Inc. All rights reserved.

Investigation of CuInSe2 nanowire arrays with core-shell structure electrodeposited at various duty cycles into anodic alumina templates

Science.gov (United States)

Cheng, Yu-Song; Wang, Na-Fu; Tsai, Yu-Zen; Lin, Jia-Jun; Houng, Mau-Phon

2017-02-01

Copper indium selenide (CuInSe2) nanowire (NW) arrays were prepared at various electrolyte duty cycles by filling anodic alumina templates through the pulsed electrodeposition technique. X-ray diffraction and scanning electron microscopy (SEM) images showed that the nucleation mechanism of CuInSe2 NW arrays was affected by the electrodeposition duty cycle. Moreover, SEM images showed that the diameter and length of the NWs were 80 nm and 2 μm, respectively. Furthermore, PEDOT/CuInSe2 NW core-shell arrays were fabricated using surfactant-modified CuInSe2 NW surfaces showing the lotus effect. Transmission electron microscopy images confirmed that a core-shell structure was achieved. Current-voltage plots revealed that the CuInSe2 NW arrays were p-type semiconductors; moreover, the core-shell structure improved the diode ideality factor from 3.91 to 2.63.

Preliminary results about Electrodeposition of Cobalt at laboratory level

International Nuclear Information System (INIS)

Cornejo, N.

1992-01-01

As of an organic compound, an extraction and Cobalt electrodeposition method had been developed as a part of fabrication aim of a sealed radioactive source with objective to the construction of density meter prototype. It was performed preliminary test of electrodeposition in the laboratory level in a simple cell. The used electrolyte had been a sulphate solution obtained by extraction of an organic solution. It is obtained a Co film by electrodeposition at 55 o C temperature and with an approximately Co concentration in 70 g/lt. (Author) 3 refs., 1 fig., 1 tab

Characterisation of electrodeposited and heat-treated Ni-Mo-P coatings

Energy Technology Data Exchange (ETDEWEB)

Melo, Regis L.; Casciano, Paulo N.S.; Correia, Adriana N.; Lima-Neto, Pedro de, E-mail: pln@ufc.br [Departamento de Quimica Analitica e Fisico-Quimica, Universidade Federal do Ceara, Fortaleza, CE (Brazil)

2012-07-01

The electrodeposition, hardness and corrosion resistance properties of Ni-Mo-P coatings were investigated. Characterisations of the electrodeposited coatings were carried out using scanning electron microscopy, X-ray diffraction and energy dispersive X-ray analysis techniques. Corrosion tests were performed at room temperature in 10-1 mol dm-3 NaCl solutions and by potentiodynamic linear polarisation. Amorphous Ni-Mo-P coatings were successfully obtained by electrodeposition using direct current. The coating composition showed to be dependent on the bath composition, current density and bath temperature. Both P and Mo contents contribute for the hardness properties of the Ni-Mo-P coatings and the absence of cracks is a requirement to produce electrodeposited Ni-Mo-P coatings with good hardness properties. The hardness values increase with heat-treatment temperature due to the precipitation of Ni, Ni{sub 3}P and NiMo phases during the heat treatment. The corrosion resistance of the electrodeposited Ni-Mo-P amorphous coatings increases with P content in the layer. Among the electrodeposited Ni-Mo-P amorphous coatings, Ni{sub 78}Mo{sub 10}P{sub 12} presented the best hardness and corrosion-resistance properties. The results showed that the addition of P is beneficial for the hardness and corrosion resistance properties of the Ni-Mo-based coatings. (author)

Electrodepositions on Tantalum in Alkali Halide Melts

DEFF Research Database (Denmark)

Barner, Jens H. Von; Jensen, Annemette Hindhede; Christensen, Erik

2013-01-01

Surface layers of tantalum metal were electrodeposited on steel from K2TaF7-LiF-NaF-KF melts. With careful control of the oxide contents dense and adherent deposits could be obtained by pulse plating. In NaCl-KCl-NaF-Na2CO3 and NaCl-KCl-Na2CO3 melts carbonate ions seems to be reduced to carbon in...

Electrodepositions on Tantalum in alkali halide melts

DEFF Research Database (Denmark)

Barner, Jens H. Von; Jensen, Annemette Hindhede; Christensen, Erik

2012-01-01

Surface layers of tantalum metal were electrodeposited on steel from K 2TaF7-LiF-NaF-KF melts. With careful control of the oxide contents dense and adherent deposits could be obtained by pulse plating. In NaCl-KCl-NaF-Na2CO3 and NaCl-KCl-Na2CO 3 melts carbonate ions seems to be reduced to carbon ...

Studies on electrodeposition and characterization of the Ni–W–Fe alloys coatings

Energy Technology Data Exchange (ETDEWEB)

Oliveira, Aldrighi Luiz M.; Costa, Josiane D.; Sousa, Mikarla B. de; Alves, José Jailson N. [Department of Chemical Engineering, Federal University of Campina Grande, Av. Aprígio Veloso, 882, 58429-970 Campina Grande (Brazil); Campos, Ana Regina N.; Santana, Renato Alexandre C. [Department of Education, Federal University of Campina Grande, R. Olho da Água da Bica, S. N., 58175-000 Cuité-Pb (Brazil); Prasad, Shiva, E-mail: prasad@deq.ufcg.edu.br [Department of Education, Federal University of Campina Grande, R. Olho da Água da Bica, S. N., 58175-000 Cuité-Pb (Brazil)

2015-01-15

Highlights: • Ni–W–Fe alloy resistant to corrosion has been obtained by electrodeposition. • Optimal temperature and current density for Ni–W–Fe alloy electrodeposition has been found. • Experimental design has been used as optimization tool. • Amorphous Ni–W–Fe alloy has been obtained. - Abstract: Corrosion has been responsible for industrial maintenance cost as well as for industrial accidents. A key to prevent corrosion is to develop advanced materials with highly anti-corrosive properties. The electrodeposition has been one of the most important techniques for obtaining these materials. The objective of this work is to develop and optimize the parameters to obtain a new Ni–W–Fe alloy with high resistance to corrosion. A factorial design 2{sup 2} with 2 center points was used to find the optimal current density and bath temperature for Ni–W–Fe electrodeposition. The influence of such variables on the cathodic current efficiency and polarization resistance were obtained. The alloys obtained with the highest current density (125 mA/cm{sup 2}) and the highest bath temperature (70 °C) had the best anticorrosive properties, which are superior to anticorrosive properties of Ni–W–Fe available in the literature. The obtained alloys had the highest tungsten content compared with other alloys studied of about 46 wt.%. The highest cathodic current efficiency was 34% for the alloy with a chemical composition of 3 wt.% Fe, 29 wt.% W and 68 wt.% Ni.

Templated electrodeposition of functional nanostructures: nanowires, nanotubes and nanocubes

NARCIS (Netherlands)

Maijenburg, A.W.

2014-01-01

This thesis is entitled “Templated electrodeposition of functional nanostructures: nanowires, nanotubes and nanocubes”. Templated electrodeposition is the synthesis technique that was used throughout this thesis, and it comprises the use of a template with specific shape and dimensions for the

Electrocatalytic reduction of carbon dioxide on electrodeposited tin-based surfaces

Science.gov (United States)

Alba, Bianca Christina S.; Camayang, John Carl A.; Mopon, Marlon L.; del Rosario, Julie Anne D.

2017-08-01

The electrocatalytic reduction of carbon dioxide to small organic molecular compounds provides a means of generating alternative fuel source while suppressing climate change. Suitable catalysts, however, are necessary to optimize its reaction kinetics towards more valuable products. Consequently, in this study, electrodeposited Sn electrodes have been developed as catalysts for CO2 electroreduction. Deposition potential was varied to produce different Sn catalysts. SEM showed varying morphologies and increasing amount as the applied potential becomes more negative. Cyclic voltammetry and chronoamperometry showed that the activity and stability of the catalysts towards CO2 reduction depend on the morphology and presence of tin oxides. These results provide a better understanding on the performance of electrodeposited Sn-based surfaces as catalysts for CO2 reduction.

Electrodeposition of lead on ITO electrode: influence of copper as an additive

International Nuclear Information System (INIS)

Avellaneda, Cesar O.; Napolitano, Marcos A.; Kaibara, Evandro K.; Bulhoes, Luis O.S.

2005-01-01

The reversible electrodeposition of metallic lead onto indium-tin oxide coated glass (ITO) was investigated and the influence of Cu(NO 3 ) 2 ·3H 2 O as additive was evaluated. The presence of Cu 2+ in the electrolytic solution produces a higher variation in the optical transmissivity. The optical response of the system changes from 85 to 10% relative to the ITO coated substrate. The kinetics of the electroreduction process of the Pb 2+ and Cu 2+ from the electrolytes has been determined by electrochemical impedance spectroscopy (EIS) at different electrodeposition potentials. This system may be a promising candidate for electrochromic materials

Synthesis and characterization of ZnO/Cu2O core–shell nanowires grown by two-step electrodeposition method

International Nuclear Information System (INIS)

Messaoudi, O.; Makhlouf, H.; Souissi, A.; Ben assaker, I.; Amiri, G.; Bardaoui, A.; Oueslati, M.; Bechelany, M.; Chtourou, R.

2015-01-01

Highlights: • ZnO/Cu 2 O core/shell nanowires have been grown by two-step electrodeposition method. • SEM confirmed the homogenous distribution of Cu 2 O on the deposited nanowires. • The X-ray diffraction demonstrated that the films were pure. • Optical transmissions measurements reveal an additional contribution at about 1.7 eV. • The ZnO/Cu 2 O structure is expected to have an advantage in photovoltaic application. - Abstract: ZnO/Cu 2 O core/shell nanowires have been grown by two-step electrodeposition method on ITO-coated glass substrates. The sample's morphology was explored by means of scanning electron microscopy (SEM). SEM images confirm the homogeneity of the nanowires and the presence of Cu 2 O shell on ZnO core. X-ray diffraction and Raman scattering measurements were used to investigate the purity and the crystallinity of the samples. Optical transmission measurements reveal an additional contribution at about 1.7 eV attributed to the type-II interfacial transition witch confirms the advantage of using the ZnO/Cu 2 O structure in photovoltaic application

The properties of electrodeposited Zn-Co coatings

Science.gov (United States)

Mahieu, J.; de Wit, K.; de Cooman, B. C.; de Boeck, A.

1999-10-01

The possibility of increasing the corrosion resistance of automotive sheet steel by electrodepositing with Zn-Co alloy coatings was investigated. Process variables during electrodeposition such as current density, electrolyte flow rate, and pH were varied in order to examine their influence on the electroplating process. Cobalt contents varying from 0.2 to 7 wt% were easily obtained. The influence of these process parameters on the characteristics of the coating could be related to the hydroxide suppression mechanism for anomalous codeposition. The structure and the morphology of the coatings were determined using SEM and XRD analysis. Application properties important for coating systems used in the automotive industry, such as friction behavior, adhesion, and corrosion behavior, were investigated on coatings with varying cobalt content. The corrosion resistance of the Zn-Co alloy layers was found to be better than that of pure zinc coatings.

Metallic amorphous electrodeposited molybdenum coating from aqueous electrolyte: Structural, electrical and morphological properties under current density

Energy Technology Data Exchange (ETDEWEB)

Nemla, Fatima [LEPCM, Department of Physics, University of Batna (Algeria); Cherrad, Djellal, E-mail: cherradphisic@yahoo.fr [Laboratory for Developing New Materials and Their Characterizations, University of Setif (Algeria)

2016-07-01

Graphical abstract: - Highlights: • Although difficulties related to electrodeposition of Mo films, we have successfully coated onto a cooper substrate. • A good formation of bcc Mo phase and lattice parameter was very accurate. • It seems that electrical properties of our samples are good and suitable as back contact for thin film solar cells. • It seems that grain size, microstrain and dislocation density are all managed and correlated to retain the resistivity to a considerable minimum value. - Abstract: Molybdenum coatings are extensively utilized as back contact for CIGS-based solar cells. However, their electrodeposition from aqueous electrolyte still sophisticates, since long time, owing to the high reactivity with oxygen. In this study, we present a successful 30 min electrodeposition experiment of somewhat thick (∼0.98–2.9 μm) and of moderate surface roughness RMS (∼47–58 nm), metallic bright Mo coating from aqueous electrolyte containing molybdate ions. XRD analysis and Hall Effect measurements have been used to confirm the presence of Mo. The crystal structure of deposits was slightly amorphous in nature to body centred cubic structure (bcc) Mo (110), (211) and (220) face. Lattice parameters exhibit some weak fluctuated tensile stress when compared to the reference lattice parameter. Additionally, our calculated lattice parameters are in good agreement with some previous works from literature. Discussions on the grain growth prove that they are constrained by grain boundary energy not the thickness effect. Further discussions were made on the electrical resistivity and surface morphology. Resonance scattering of Fermi electrons are expected to contribute towards the variation in the film resistivity through the carrier mobility limitation. However, studied samples might be qualified as candidates for solar cell application.

Effect of the electrochemical technique on nanocrystalline ZnO electrodeposition, its structural, morphological and photoelectrochemical properties

Energy Technology Data Exchange (ETDEWEB)

Chettah, Hamdane; Abdi, Djamila, E-mail: naimadjam@hotmail.com

2013-06-30

This article reports the influence of the electrochemical technique on the electrodeposition of nanoscopic zinc oxide from aqueous mixed bath of zinc nitrate and potassium chloride at 70 °C onto fluorine doped tin oxide coated glass substrates. ZnO thin films were elaborated via cyclic voltamperometry and chronoamperometry techniques. This study shows structural and morphological differences in films deposited according to both methods. Thin and adherent films obtained via cyclic voltamperometry have been obtained after 100 cycles, and those obtained using the chronoampermetric method grown at potential of − 1 V vs. Ag/AgCl during 1 h. The structural characterisation of such films was performed using X-ray diffraction, which showed the most important peaks of ZnO wurtzite structure with preferential orientation along the (002) axis for deposits obtained via cyclic voltamperometry presenting nanometric grain sizes (42 nm). Atomic force microscopy was used to study surface morphology and estimate the surface roughness factor for two deposits. Photoelectrochemical study indicates that both kinds of films had n-type electrical conductivity and presents high photoanodic-generated currents. - Highlights: • Zinc oxide films were electrodeposited on fluorine doped tin oxide substrates at 70 °C. • Two electrochemical techniques were used cyclic voltamperometry and chronoamperometry. • X-ray diffraction showed the most important peaks of ZnO wurtzite structure. • Preferential orientation along the (002) axis for cyclic voltamperometry films. • Deposits had n-type electrical conductivity and high photoanodic-generated currents.

Electrodeposition of Metal on GaAs Nanowires

Science.gov (United States)

Liu, Chao; Einabad, Omid; Watkins, Simon; Kavanagh, Karen

2010-10-01

Copper (Cu) electrical contacts to freestanding gallium arsenide (GaAs) nanowires have been fabricated via electrodeposition. The nanowires are zincblende (111) oriented grown epitaxially on n-type Si-doped GaAs (111)B substrates by gold-catalyzed Vapor Liquid Solid (VLS) growth in a metal organic vapour phase epitaxy (MOVPE) reactor. The epitaxial electrodeposition process, based on previous work with bulk GaAs substrates, consists of a substrate oxide pre-etch in dilute ammonium-hydroxide carried out prior to galvanostatic electrodeposition in a pure Cu sulphate aqueous electrolyte at 20-60^oC. For GaAs nanowires, we find that Cu or Fe has a preference for growth on the gold catalyst avoiding the sidewalls. After removing gold, both metals still prefer to grow only on top of the nanowire, which has the largest potential field.

Electrodeposited Ni-W magnetic thin films with columnar nanocrystallites

International Nuclear Information System (INIS)

Sulitanu, N.; Brinza, F.

2002-01-01

Nanocrystalline Ni-W thin films (140 nm) containing from zero to 18 wt % W were electrolytically prepared and structural and magnetic characterized. XRD, SEM and TEM investigations have revealed that all segregated Ni columns are fcc-type whose [111] axis is oriented perpendicular to the film plane and have 140 nm in height and 6-27 nm in diameter. Depending on film composition, two types of nanostructures were observed: (a) single-phase nanostructure ( i nterphases , namely W enriched particles boundaries, and (b) two-phase nanostructure (7-18 wt %) in which a second Ni-W amorphous phase or even amorphous-disordered mixture separates the magnetic columnar Ni nanocrystallites (d = 6-14 nm). The columnar crystallites have an easy magnetization direction along their long axis mainly due to the in-plane internal biaxial stresses. Magnetic characteristics of prepared thin films are presented. (Authors)

Properties and electrochemical behaviors of AuPt alloys prepared by direct-current electrodeposition for lithium air batteries

International Nuclear Information System (INIS)

Zhang, Jinqiu; Li, Da; Zhu, Yiming; Chen, Miaomiao; An, Maozhong; Yang, Peixia; Wang, Peng

2015-01-01

AuPt catalyst has a prospective application in a lithium air battery because of its bi-function on catalyzing Oxygen Reduction Reaction (ORR) and Oxygen Evolution Reaction (OER). Electrodeposition is an in-situ convenient technology for catalyst preparation without chemical residue. In an acid electrolyte, AuPt alloy catalysts were electrodeposited on carbon paper. The effect of main salt concentration, electrodeposition time and current density were studied by deposit micromorphology observation, structure analyses and composition testing. Catalytic abilities of AuPt alloys were measured by cyclic voltammetry (CV) in an ionic liquid of EMI-TFSI/Li-TFSI [1- Ethyl - 3- methylimidazolium–bis (trifluoromethanesulphonyl) imide/lithium–bis (trifluoromethanesulphonyl) imide]. The electrochemical behaviors of Au, Pt and AuPt deposits were also measured. An optimized direct-current electrodeposition process of getting high active AuPt catalyst is concluded, which is an aqueous solution containing 6.7∼10 mmol · L −1 HAuCl 4 , 10∼13.3 mmol · L −1 H 2 PtCl 6 and 0.5 mol · L −1 H 2 SO 4 as the electrolyte, current density of 20mA · cm −2 and electrodeposition time of 8∼34 s. The co-deposition of AuPt alloy is an irregular co-deposition controlled by diffusion, while gold atoms enter the platinum’s crystal lattice in the structure of AuPt alloy. The increase of the concentration of H 2 PtCl 6 in the electrolyte, the extension of the electrodeposition time or the raise of the current density can improve the content of Pt in the deposit. The clusters’ diameters of AuPt catalysts decrease to 150∼250 nm by adjusting current densities during electrodeposition

Electrochemical studies of iron/carbonates system applied to the formation of thin layers of siderite on inert substrates

International Nuclear Information System (INIS)

Ithurbide, A.; Peulon, S.; Mandin, Ph.; Beaucaire, C.; Chausse, A.

2007-01-01

In order to understand the complex mechanisms of the reactions occurring, a methodology is developed. It is based on the use of compounds electrodeposited under the form of thin layers and which are used then as electrodes to study their interactions with the toxic species. It is in this framework that is studied the electrodeposition of siderite on inert substrates. At first, have been studied iron electrochemical systems in carbonated solutions. These studies have been carried out with classical electrochemical methods (cyclic voltametry, amperometry) coupled to in-situ measurements: quartz microbalance, pH. Different compounds have been obtained under the form of homogeneous and adherent thin layers. The analyses of these depositions, by different ex-situ characterizations (XRD, IR, SEM, EDS..) have revealed particularly the presence of siderite. Then, the influence of several experimental parameters (substrate, potential, medium composition, temperature) on the characteristics of siderite thin layers has been studied. From these experimental results, models have been proposed. (O.M.)

Growth and Characterization of PbO Nano rods Grown using Facile Oxidation of Lead Sheet

International Nuclear Information System (INIS)

Yousefi, R.; Sheini, F.J.; Saaedi, A.; Cheraghizade, M.

2015-01-01

PbO nano rods were synthesized by oxidation of lead sheets under an oxygen ambience with different temperatures at 330, 400, 450 and 550 degree Celsius in a tube furnace. Scanning electron microscope (SEM) results showed that the nano rods started growing on the sheet that was placed at 330 degree Celsius. On the other hand, by increasing of the temperature to 550 degree Celsius more nano rods appeared on the Pb sheet, which were lied on the lead sheet. X-ray diffraction pattern (XRD) indicated that the nano rods had α-PbO structures. However, a few β-PbO phases also appeared for the nano rods. Raman measurements confirmed the XRD results and indicated two Raman active modes that belonged to α-PbO phase for the nano rods. In addition, the Raman spectrum of the nano rods showed a weak peak of the β-PbO structure. The optical properties of the products were characterized using a room temperature photoluminescence (PL) technique. The PL result indicated a band gap for the PbO nano rods in the visible region. (author)

Electric characterization of GaAs deposited on porous silicon by electrodeposition technique

International Nuclear Information System (INIS)

Lajnef, M.; Chtourou, R.; Ezzaouia, H.

2010-01-01

GaAs thin films were synthesized on porous Si substrate by the electrodeposition technique. The X-ray diffraction studies showed that the as-grown films were crystallised in mixed phase nature orthorhombic and cubic of GaAs. The GaAs film was then electrically characterized using current-voltage (I-V) and capacitance-voltage (C-V) techniques by the way of Al/GaAs Schottky junctions. The electric analysis allowed us to determine the n factor and the barrier height φ b0 parameters of Al/GaAs Schottky junctions. The (C-V) characteristics were recorded at frequency signal 1 MHz in order to identify the effect of the surface states on the behaviour of the capacitance of the device.

Electrodeposition of gold templated by patterned thiol monolayers

Energy Technology Data Exchange (ETDEWEB)

She, Zhe [EaStCHEM School of Chemistry, University of St. Andrews, KY16 9ST (United Kingdom); Di Falco, Andrea [SUPA, School of Physics and Astronomy, University of St. Andrews, KY16 9SS (United Kingdom); Hähner, Georg [EaStCHEM School of Chemistry, University of St. Andrews, KY16 9ST (United Kingdom); Buck, Manfred, E-mail: mb45@st-andrews.ac.uk [EaStCHEM School of Chemistry, University of St. Andrews, KY16 9ST (United Kingdom)

2016-06-15

Graphical abstract: - Highlights: • First demonstration of electrodeposition/lift-off of gold using thiol monolayers. • Microelectrode structures with large length to width ratio were generated. • Performance of two different patterning techniques was investigated. • Conditions for achieving good contrast in the electrodeposition were established. - Abstract: The electrochemical deposition of Au onto Au substrates modified by self-assembled monolayers (SAMs) was studied by linear sweep voltammetry (LSV), atomic force microscopy (AFM) and scanning electron microscopy (SEM). Patterned SAMs exhibiting electrochemical contrast were prepared by two different methods. One used microcontact printing (μCP) to generate a binary SAM of ω-(4′-methyl-biphenyl-4-yl)-propane thiol (CH{sub 3}-C{sub 6}H{sub 4}-C{sub 6}H{sub 4}-(CH{sub 2}){sub 3}-SH, MBP3) and octadecane thiol (CH{sub 3}(CH{sub 2}){sub 17}SH, ODT). Templated by the SAM, a gold microelectrode structure was electrodeposited featuring a line 15 μm wide and 3 mm long. After transfer to an epoxy substrate the structure proved to be electrically conductive across the full length. The other patterning method applied electron beam lithography (EBL) where electrochemical contrast was achieved by crosslinking molecules in a single component SAM of MBP3. An electron dose above 250 mC/cm{sup 2} results in a high deposition contrast. The choice of parameters for the deposition/lift-off process is found to be more critical for Au compared to Cu studied previously. The origin of the differences and implications for nanoscale patterning are discussed.

Evaluation of charge storage ability of chrome doped Mn2O3 nanostructures derived by cathodic electrodeposition

OpenAIRE

Hamideh Darjazi; Saied Saeed Hosseiny Davarani; Hamid Reza Moazami; Taher Yousefi; Farideh Tabatabaei

2016-01-01

A facile synthetic route has been proposed to prepare cauliflower-like nanostructures of Cr doped Mn2O3. The synthesis was carried out by constant current cathodic electrodeposition from Mn2+ nitrate solutions containing minor amounts of dichromate. It was found that the presence of Cr mediates the formation of cathodic MnO2 which then reacts with the excess Mn2+ species to form Mn2O3 nanostructures. X-Ray Diffraction (XRD), Scanning Electron Microscopy (SEM) and Differential Thermal Analysis...

Stability of an Electrodeposited Nanocrystalline Ni-Based Alloy Coating in Oil and Gas Wells with the Coexistence of H2S and CO2

Directory of Open Access Journals (Sweden)

Yiyong Sui

2017-06-01

Full Text Available The stability of an electrodeposited nanocrystalline Ni-based alloy coating in a H2S/CO2 environment was investigated by electrochemical measurements, weight loss method, and surface characterization. The results showed that both the cathodic and anodic processes of the Ni-based alloy coating were simultaneously suppressed, displaying a dramatic decrease of the corrosion current density. The corrosion of the Ni-based alloy coating was controlled by H2S corrosion and showed general corrosion morphology under the test temperatures. The corrosion products, mainly consisting of Ni3S2, NiS, or Ni3S4, had excellent stability in acid solution. The corrosion rate decreased with the rise of temperature, while the adhesive force of the corrosion scale increased. With the rise of temperature, the deposited morphology and composition of corrosion products changed, the NiS content in the corrosion scale increased, and the stability and adhesive strength of the corrosion scale improved. The corrosion scale of the Ni-based alloy coating was stable, compact, had strong adhesion, and caused low weight loss, so the corrosion rates calculated by the weight loss method cannot reveal the actual oxidation rate of the coating. As the corrosion time was prolonged, the Ni-based coating was thinned while the corrosion scale thickened. The corrosion scale was closely combined with the coating, but cannot fully prevent the corrosive reactants from reaching the substrate.

Conductance quantization in magnetic nanowires electrodeposited in nanopores

DEFF Research Database (Denmark)

Elhoussine, F.; Mátéfi-Tempfli, Stefan; Encinas, A.

2002-01-01

Magnetic nanocontacts have been prepared by a templating method that involves the electrodeposition of Ni within the pores of track-etched polymer membranes. The nanocontacts are made at the extremity of a single Ni nanowire either inside or outside the pores. The method is simple, flexible...... degeneracy. Our fabrication method enables future investigation of ballistic spin transport phenomena in electrodeposited magnetic nanocontacts....

Cathodic electrodeposition of ceramic and organoceramic materials. Fundamental aspects.

Science.gov (United States)

Zhitomirsky, I

2002-03-29

Electrodeposition of ceramic materials can be performed by electrophoretic (EPD) or electrolytic (ELD) deposition. Electrophoretic deposition is achieved via motion of charged particles towards an electrode under an applied electric field. Electrolytic deposition produces colloidal particles in cathodic reactions for subsequent deposition. Various electrochemical strategies and deposition mechanisms have been developed for electrodeposition of ceramic and organoceramic films, and are discussed in the present article. Electrode-position of ceramic and organoceramic materials includes mass transport, accumulation of particles near the electrode and their coagulation to form a cathodic deposit. Various types of interparticle forces that govern colloidal stability in the absence and presence of processing additives are discussed. Novel theoretical contributions towards an interpretation of particle coagulation near the electrode surface are reviewed. Background information is given on the methods of particle charging, stabilization of colloids in aqueous and non-aqueous media, electrophoretic mobility of ceramic particles and polyelectrolytes, and electrode reactions. This review also covers recent developments in the electrodeposition of ceramic and organoceramic materials.

Electrodeposition and surface finishing fundamentals and applications

CERN Document Server

Djokic, Stojan

2014-01-01

This volume of Modern Aspects of Electrochemistry has contributions from significant individuals in electrochemistry. This 7 chapter book discusses electrodeposition and the characterization of alloys and composite materials, the mechanistic aspects of lead electrodeposition, electrophoretic deposition of ceramic materials onto metal surfaces and the fundamentals of metal oxides for energy conversion and storage technologies. This volume also has a chapter devoted to the anodization of aluminum, electrochemical aspects of chemical and mechanical polishing, and surface treatments prior to metal

Material reliability of Ni alloy electrodeposition for steam generator tube repair

International Nuclear Information System (INIS)

Kim, Dong Jin; Kim, Myong Jin; Kim, Joung Soo; Kim, Hong Pyo

2007-01-01

Due to the occasional occurrences of Stress Corrosion Cracking (SCC) in steam generator tubing (Alloy 600), degraded tubes are removed from service by plugging or are repaired for re-use. Since electrodeposition inside a tube dose not entail parent tube deformation, residual stress in the tube can be minimized. In this work, tube restoration via electrodeposition inside a steam generator tubing was performed after developing the following: an anode probe to be installed inside a tube, a degreasing condition to remove dirt and grease, an activation condition for surface oxide elimination, a tightly adhered strike layer forming condition between the electroforming layer and the Alloy 600 tube, and the condition for an electroforming layer. The reliability of the electrodeposited material, with a variation of material properties, was evaluated as a function of the electrodeposit position in the vertical direction of a tube using the developed anode. It has been noted that the variation of the material properties along the electrodeposit length was acceptable in a process margin. To improve the reliability of a material property, the causes of the variation occurrence were presumed, and an attempt to minimize the variation has been made. A Ni alloy electrodeposition process is suggested as a Primary Water Stress Corrosion Cracking (PWSCC) mitigation method for various components, including steam generator tubes. The Ni alloy electrodeposit formed inside a tube by using the installed assembly shows proper material properties as well as an excellent SCC resistance

Electrodeposited Silver Nanoparticles Patterned Hexagonally for SERS

International Nuclear Information System (INIS)

Gu, Geun Hoi; Lee, Sue Yeone; Suh, Jung Sang

2010-01-01

We have fabricated hexagonally patterned silver nanoparticles for surface-enhanced Raman scattering (SERS) by electrodepositing silver on the surface of an aluminum plate prepared by completely removing the oxide from anodic aluminum oxide (AAO) templates. Even after completely removing the oxide, well-ordered hexagonal patterns, similar to the shape of graphene, remained on the surface of the aluminum plate. The borders of the hexagonal pattern protruded up to form sorts of nano-mountains at both the sides and apexes of the hexagon, with the apexes protruding even more significantly than the sides. The aluminum plate prepared by completely removing the oxide has been used in the preparation of SERS substrates by sputter-coating of gold or silver on it. Instead of sputter-coating, here we have electro-deposited silver on the aluminum plate. When silver was electro-deposited on the plate, silver nanoparticles were made along the hexagonal margins.

Structure characterization of nanocrystalline Ni–W alloys obtained by electrodeposition

Energy Technology Data Exchange (ETDEWEB)

Indyka, P., E-mail: paulina.indyka@uj.edu.pl [Jagiellonian University, Faculty of Chemistry, 3 Ingardena St., 30-059 Krakow (Poland); Beltowska-Lehman, E.; Tarkowski, L.; Bigos, A. [Institute of Metallurgy and Materials Science, Polish Academy of Sciences, 25 Reymonta St., 30-059 Krakow (Poland); García-Lecina, E. [Surface Finishing Department, CIDETEC-IK4 – Centre for Electrochemical Technologies, P° Miramón 196, 20009 Donostia-San Sebastián (Spain)

2014-03-25

Highlights: • Ni–W alloy coatings were electrodeposited from an aqueous electrolyte solutions. • The microstructure was studied with respect to electrodeposition process parameters. • We report optimal plating conditions for crack-free, nanocrystalline Ni–W coatings. • Crystalline Ni–W coatings exhibited the phase structure of an α-Ni(W) solid solution. • Coatings revealed tensile residual stresses and weakly pronounced 〈1 1 0〉 fiber texture. -- Abstract: Ni–W coatings of different tungsten content (2–50 wt%) were electrodeposited on a steel substrates from an aqueous complex sulfate–citrate galvanic baths, under controlled hydrodynamic conditions in a Rotating Disk Electrode (RDE) system. The optimum conditions for the electrodeposition of crack-free, homogeneous nanocrystalline Ni–W coatings were determined on the basis of the microstructure investigation results. The XRD structural characterizations of Ni–W alloy coatings obtained under different experimental conditions were complemented by SEM and TEM analysis. Results of the study revealed that the main factor influencing the microstructure formation of the Ni–W coatings is the chemical composition of an electrolyte solution. X-ray and electron diffraction patterns of all nanocrystalline Ni–W coatings revealed mainly the fcc phase structure of an α-Ni(W) solid solution with a lattice parameter increased along with tungsten content. The use of additives in the plating bath resulted in the formation of equiaxial/quasifibrous, nanocrystalline Ni–W grains of an average size of about 10 nm. The coatings were characterized by relatively high tensile residual stresses (500–1000 MPa), depending on the electrodeposition conditions. Ni–W coatings exhibited weakly pronounced fiber type 〈1 1 0〉 crystallographic texture, consistent with the symmetry of the plating process. Coatings of the highest tungsten content 50 wt% were found to be amorphous.

Electrodeposition of zinc oxide/tetrasulfonated copper phthalocyanine hybrid thin film for dye-sensitized solar cell application

International Nuclear Information System (INIS)

Luo Xinze; Xu Lin; Xu Bingbing; Li Fengyan

2011-01-01

Hybrid film of zinc oxide (ZnO) and tetrasulfonated copper phthalocyanine (TSPcCu) was grown on an indium tin oxide (ITO) glass by one-step cathodic electrodeposition from aqueous mixtures of Zn(NO 3 ) 2 , TSPcCu and KCl. The addition of TSPcCu strongly influences the morphology and crystallographic orientation of the ZnO. The nanosheets stack of ZnO leads to a porous surface structure which is advantageous to further adsorb organic dyes. The photovoltaic properties were investigated by assembling the DSSC device based on both the only ZnO film and the ZnO/TSPcCu hybrid films. Photoelectrochemical analysis revealed that the optimized DSSC device with TSPcCu represented a more than three-fold improvement in power conversion efficiency than the device without TSPcCu. The DSSC based on ZnO/TSPcCu hybrid films demonstrates an open circuit voltage of 0.308 V, a short circuit current of 90 μA cm -2 , a fill factor of 0.26, and a power conversion efficiency of 0.14%.

Electrodeposition of zinc oxide/tetrasulfonated copper phthalocyanine hybrid thin film for dye-sensitized solar cell application

Energy Technology Data Exchange (ETDEWEB)

Luo Xinze [Key Laboratory of Polyoxometalates Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024 (China); College of Chemistry and Biological Science, Yili Normal University, Yining 835000, (China); Xu Lin, E-mail: linxu@nenu.edu.cn [Key Laboratory of Polyoxometalates Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024 (China); Xu Bingbing; Li Fengyan [Key Laboratory of Polyoxometalates Science of Ministry of Education, College of Chemistry, Northeast Normal University, Changchun 130024 (China)

2011-05-15

Hybrid film of zinc oxide (ZnO) and tetrasulfonated copper phthalocyanine (TSPcCu) was grown on an indium tin oxide (ITO) glass by one-step cathodic electrodeposition from aqueous mixtures of Zn(NO{sub 3}){sub 2}, TSPcCu and KCl. The addition of TSPcCu strongly influences the morphology and crystallographic orientation of the ZnO. The nanosheets stack of ZnO leads to a porous surface structure which is advantageous to further adsorb organic dyes. The photovoltaic properties were investigated by assembling the DSSC device based on both the only ZnO film and the ZnO/TSPcCu hybrid films. Photoelectrochemical analysis revealed that the optimized DSSC device with TSPcCu represented a more than three-fold improvement in power conversion efficiency than the device without TSPcCu. The DSSC based on ZnO/TSPcCu hybrid films demonstrates an open circuit voltage of 0.308 V, a short circuit current of 90 {mu}A cm{sup -2}, a fill factor of 0.26, and a power conversion efficiency of 0.14%.

Investigation of water content in electrolyte solution on electrochromic properties of WO3 thin Films

Directory of Open Access Journals (Sweden)

Zahra Abadi

2017-05-01

Full Text Available Tungsten oxide thin films were prepared by a cathodic electrodeposition method at -0.450 mV in order to investigate how water content affects their electrochromic properties. FESEM images exhibit that WO3 thin films consist of 65 nm uniform grains. Thin Films were electrochemically investigated in 0.1M LiClO4 in propylene carbonate electrolyte with and without 5vol% water content by cyclic voltammetry and chronoamperometry. The results indicate that tungsten oxide thin films exhibit faster switching time between coloration and bleaching states and also higher coloration efficiency in hydrated electrolyte.  

Magnetic properties of CoP alloys electrodeposited at room temperature

International Nuclear Information System (INIS)

Lucas, I.; Perez, L.; Aroca, C.; Sanchez, P.; Lopez, E.; Sanchez, M.C.

2005-01-01

CoP alloys have been electrodeposited at room temperature from electrolytes with different pH values and their magnetic properties have been studied. Cracks and fractures appear when using stiff substrates, showing that high internal stresses, due to hydrogen evolution, are involved in the electrodeposition process. Samples electrodeposited onto flexible substrates do not show cracks on the surface. We also report an increment in the coercivity of the alloys when the pH of the electrolyte decreases, and therefore, the hydrogen evolution and the internal stresses increase

Effect of weak magnetic field on the grain size of electrodeposited nickel

International Nuclear Information System (INIS)

Ansari, M.S.; Gul, N.

2007-01-01

Effect of weak magnetic field on the electro-deposition of nickel onto copper electrode has been investigated. The working conditions were optimized through adjustment of cathodic current density (CCD), deposition time, bath temperature and pH of the medium. For electro-deposition in the absence of magnetic field, the optimum conditions comprised of pH = 4.0+- 0.5, average CCD = 22.5 +- 0.5 mA cm/sup -2/ and bath temperature in the range from 25 to 30 degree C. The same conditions were maintained for the electrodeposition while applying magnetic field of 0.75 kG. The morphological features of the Ni-deposits on copper cathode were compared for the two cases. The applied magnetic field not only enhanced the amount of nickel deposition but also improved the quality of the deposit. Surface morphology of the electro-deposited nickel has been monitored using scanning electron microscopy (SEM); the preliminary investigation has shown that the grain size decreased with the applied magnetic field case. One possible explanation to this behavior is the convection flow of cations close to the electrode surface induced by the Lorentz force which also influences the ion-migration. (author)

Effects of Electrodeposition Mode and Deposition Cycle on the Electrochemical Performance of MnO2-NiO Composite Electrodes for High-Energy-Density Supercapacitors.

Science.gov (United States)

Rusi; Majid, S R

2016-01-01

Nanostructured network-like MnO2-NiO composite electrodes were electrodeposited onto stainless steel substrates via different electrodeposition modes, such as chronopotentiometry, chronoamperometry, and cyclic voltammetry, and then subjected to heat treatment at 300°C for metal oxide conversion. X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy were used to study the crystalline natures and morphologies of the deposited films. The electrochemical properties were investigated using cyclic voltammetry and charge/discharge tests. The results revealed that the electrochemical performance of the as-obtained composite electrodes depended on the electrodeposition mode. The electrochemical properties of MnO2-NiO composite electrodes prepared using cyclic voltammetry exhibited the highest capacitance values and were most influenced by the deposition cycle number. The optimum specific capacitance was 3509 Fg-1 with energy and power densities of 1322 Wh kg-1 and 110.5 kW kg-1, respectively, at a current density of 20 Ag-1 in a mixed KOH/K3Fe(CN)6 electrolyte.

Effects of Electrodeposition Mode and Deposition Cycle on the Electrochemical Performance of MnO2-NiO Composite Electrodes for High-Energy-Density Supercapacitors.

Directory of Open Access Journals (Sweden)

Rusi

Full Text Available Nanostructured network-like MnO2-NiO composite electrodes were electrodeposited onto stainless steel substrates via different electrodeposition modes, such as chronopotentiometry, chronoamperometry, and cyclic voltammetry, and then subjected to heat treatment at 300°C for metal oxide conversion. X-ray diffraction, field emission scanning electron microscopy, and transmission electron microscopy were used to study the crystalline natures and morphologies of the deposited films. The electrochemical properties were investigated using cyclic voltammetry and charge/discharge tests. The results revealed that the electrochemical performance of the as-obtained composite electrodes depended on the electrodeposition mode. The electrochemical properties of MnO2-NiO composite electrodes prepared using cyclic voltammetry exhibited the highest capacitance values and were most influenced by the deposition cycle number. The optimum specific capacitance was 3509 Fg-1 with energy and power densities of 1322 Wh kg-1 and 110.5 kW kg-1, respectively, at a current density of 20 Ag-1 in a mixed KOH/K3Fe(CN6 electrolyte.

Electro-deposition of nickel, on reactor seal discs

International Nuclear Information System (INIS)

Vernekar, R.B.; Bhide, G.K.

1977-01-01

The effect of plating variables, acidity, current density and temperature on hardness of nickel deposited from purified nickel sulfamate bath has been investigated and optimum conditions for electrodeposition of nickel plating of hardness 160-170 VHN on reactor seal discs are established. Sodium lauryl sulfate was added as a wetting agent to the bath to overcome pitting tendency of the deposit. Factors affecting hydrogen absorption by electrodeposited nickel are also discussed. It is observed that : (1) at a pH 3.5 - 4.0 the decomposition rate of sulfamate salt is almost negligible and is the best value for bath operation, (2) at 15 A/dm 2 the hardness value is consistently around 160-170 VHN, (3) the temperatures less than 50 0 C give harder deposits and the bath is best operated at temperature 50-60 0 C and (4) annealing of the plated discs substantially reduces the hardness. (M.G.B.)

Electrodeposition of quaternary alloys in the presence of magnetic field

Science.gov (United States)

2010-01-01

Electrodeposition of Ni-Co-Fe-Zn alloys was done in a chloride ion solution with the presence and absence of a Permanent Parallel Magnetic Field (PPMF). The PPMF was applied parallel to the cathode surface. The deposition profile was monitored chronoamperometrically. It was found that the electrodeposition current was enhanced in the presence of PPMF (9 T) compared to without PPMF. The percentage of current enhancement (Γ%) was increased in the presence of PPMF, with results of Γ% = 11.9%, 16.7% and 18.5% at -1.1, -1.2 and -1.3 V respectively for a 2400 sec duration. In chronoamperometry, the Composition Reference Line (CRL) for Ni was around 57%, although the nobler metals (i.e. Ni, Co) showed anomalous behaviour in the presence of Zn and Fe. The anomalous behaviour of the Ni-Co-Fe-Zn electrodeposition was shown by the Energy Dispersive X-Ray (EDX) results. From Atomic Force Microscopy (AFM) measurements, it was found that the surface roughness of the Ni-Co-Fe-Zn alloy films decreased in the presence of a PPMF. PMID:20604934

Electrodeposited binder-free NiCo2O4@carbon nanofiber as a high performance anode for lithium ion batteries

Science.gov (United States)

Zhang, Jie; Chu, Ruixia; Chen, Yanli; Jiang, Heng; Zhang, Ying; Huang, Nay Ming; Guo, Hang

2018-03-01

Binder-free nickel cobaltite on a carbon nanofiber (NiCo2O4@CNF) anode for lithium ion batteries was prepared via a two-step procedure of electrospinning and electrodeposition. The CNF was obtained by annealing electrospun poly-acrylonitrile (PAN) in nitrogen (N2). The NiCo2O4 nanostructures were then grown on the CNF by electrodeposition, followed by annealing in air. Experimental results showed that vertically aligned NiCo2O4 nanosheets had uniformly grown on the surface of the CNF, forming an interconnected network. The NiCo2O4@CNF possessed considerable lithium storage capacity and cycling stability. It exhibited a high reversible capacity of 778 mAhg-1 after 300 cycles at a current density of 0.25 C (1 C = 890 mAg-1) with an average capacity loss rate of 0.05% per cycle. The NiCo2O4@CNF had considerable rate capacities, delivering a capacity of 350 mAhg-1 at a current density of 2.0 C. The outstanding electrochemical performance can be mainly attributed to the following: (1) The nanoscale structure of NiCo2O4 could not only shorten the diffusion path of lithium ions and electrons but also increase the specific surface area, providing more active sites for electrochemical reactions. (2) The CNF with considerable mechanical strength and electrical conductivity could function as an anchor for the NiCo2O4 nanostructure and ensure an efficient electron transfer. (3) The porous structure resulted in a high specific surface area and an effective buffer for the volume changes during the repeated charge-discharge processes. Compared with a conventional hydrothermal method, electrodeposition could significantly simplify the preparation of NiCo2O4, with a shorter preparation period and lower energy consumption. This work provides an alternative strategy to obtain a high performance anode for lithium ion batteries.

Synthesis and characterization of ZnO/Cu{sub 2}O core–shell nanowires grown by two-step electrodeposition method

Energy Technology Data Exchange (ETDEWEB)

Messaoudi, O., E-mail: olfamassaoudi@gmail.com [Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l’Energie, Technopole Borj Cedria, B.P. 95, Hammam Lif, 2050 (Tunisia); Makhlouf, H.; Souissi, A.; Ben assaker, I. [Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l’Energie, Technopole Borj Cedria, B.P. 95, Hammam Lif, 2050 (Tunisia); Amiri, G. [Groupe d’Etude de la Matière Condensée, CNRS Université de Versailles Saint Quentin (France); Bardaoui, A. [Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l’Energie, Technopole Borj Cedria, B.P. 95, Hammam Lif, 2050 (Tunisia); Physics Department, Taif University (Saudi Arabia); Oueslati, M. [Unité Nanomatériaux et Photonique, Faculté Des Sciences de Tunis, Campus Universitaire El Manar, 2092, Tunis (Tunisia); Bechelany, M. [European Institute of Membranes (IEM ENSCM UM2 CNRS UMR 5635), University of Montpellier 2, 34095 Montpellier (France); Chtourou, R. [Laboratoire de Photovoltaïque, Centre de Recherches et des Technologies de l’Energie, Technopole Borj Cedria, B.P. 95, Hammam Lif, 2050 (Tunisia)

2015-07-15

Highlights: • ZnO/Cu{sub 2}O core/shell nanowires have been grown by two-step electrodeposition method. • SEM confirmed the homogenous distribution of Cu{sub 2}O on the deposited nanowires. • The X-ray diffraction demonstrated that the films were pure. • Optical transmissions measurements reveal an additional contribution at about 1.7 eV. • The ZnO/Cu{sub 2}O structure is expected to have an advantage in photovoltaic application. - Abstract: ZnO/Cu{sub 2}O core/shell nanowires have been grown by two-step electrodeposition method on ITO-coated glass substrates. The sample's morphology was explored by means of scanning electron microscopy (SEM). SEM images confirm the homogeneity of the nanowires and the presence of Cu{sub 2}O shell on ZnO core. X-ray diffraction and Raman scattering measurements were used to investigate the purity and the crystallinity of the samples. Optical transmission measurements reveal an additional contribution at about 1.7 eV attributed to the type-II interfacial transition witch confirms the advantage of using the ZnO/Cu{sub 2}O structure in photovoltaic application.

Preparation of n- and p-InP films by PH{sub 3} treatment of electrodeposited In layers

Energy Technology Data Exchange (ETDEWEB)

Cattarin, S.; Musiani, M. [C.N.R., Padova (Italy). Istituto di Polarografia ed Elettrochimica Preparativa; Casellato, U.; Rossetto, G. [C.N.R., Padova (Italy). Istituto di Chimica e Tecnologie Inorganische e dei Materiali Avanzati; Razzini, G. [Politecnico di Milano (Italy). Dipt. di Chimica Fisica Applicata; Decker, F.; Scrosati, B. [Univ. La Sapienza, Roma (Italy). Dipt. di Chimica

1995-04-01

InP is among the few semiconducting materials with the potential for excellence in several applications, including solar energy conversion. Thin InP layers have been prepared by electrodeposition of In films on Ti substrates (ca. 2 mg/cm{sup 2} of In) and their annealing in PH{sub 3} flow. The obtained material, characterized by scanning electron microscopy-energy dispersive X-ray analysis and X-ray diffraction techniques, shows uneven substrate coverage but good crystallinity. Photoelectrochemical investigations in acidic polyiodide medium show significant n-type photoactivity for the samples prepared from a nominally pure In layer. A p-type photoactivity is obtained depositing a small amount of Zn on top of the In layer prior to annealing. Results are compared with those obtained preparing InP layers on Ti by a conventional metallorganic chemical vapor deposition technique.

Dendrite-Free Electrodeposition and Reoxidation of Lithium-Sodium Alloy for Metal-Anode Battery

Science.gov (United States)

2011-11-01

Dendrite-Free Electrodeposition and Reoxidation of Lithium-Sodium Alloy for Metal-Anode Battery Johanna K. Star 1 , Yi Ding 2 , and Paul A. Kohl ,1, * 1...Journal Article 3. DATES COVERED 01-11-2011 to 01-11-2011 4. TITLE AND SUBTITLE DENDRITE-FREE ELECTRODEPOSITION AND REOXIDATION OF LITHIUM-SODIUM...can short circuit the anode and cathode . Anode- cathode short circuits are especially dangerous when a flammable organic solvent is used as the

Technetium electrodeposition from aqueous formate solutions at graphite electrode: electrochemical study

International Nuclear Information System (INIS)

Maslennikov, A.; Peretroukhine, V.; Masson, M.; Lecomte, M.

1999-01-01

Recovery of technetium from aqueous formate buffer solutions of ionic strength μ = 1.0 was studied in the pH interval from 1.6 to 7.5 at graphite cathode in an electrolytic cell with separated compartments was studied, using cyclic voltammetry (CV) and inverse stripping voltammetry (ISV) techniques. It has been shown that Tc electrodeposition process becomes possible at the potentials of graphite cathode E cath. 1/2 = -0.72±0.02 V/SCE and was pH independent in the interval pH = 3.46-7.32. Mechanism of electrodeposition, including Tc(VII)/Tc(IV) reduction in the solution followed by Tc(IV) hydrolysis at the electrode surface with formation of hydrated Tc oxide cathodic deposit has been proposed. The further precision of the Tc(VII) electrochemical reduction mechanism in formate buffer media and optimization of the electrodeposition process seems to be possible using additional analytical facilities except electrochemical methods. (orig.)

Correlation between crystallographic texture, microstructure and magnetic properties of pulse electrodeposited nanocrystalline Nickel–Cobalt alloys

Energy Technology Data Exchange (ETDEWEB)

Sharma, Amit; Chhangani, Sumit; Madhavan, R.; Suwas, Satyam, E-mail: satyamsuwas@materials.iisc.ernet.in

2017-07-15

Highlights: • Nano-crystalline Ni–Co materials with varying composition has been deposited by pulse electrodeposition. • Overall weakening of <1 1 1> texture and strengthening of <2 0 0> fibre texture is observed with increasing cobalt content. • Higher thermal stability of Ni–70Co is interpreted in terms of low mobility twins and texture. • A clear transition from soft to hard magnetic character is observed with an increase cobalt content. - Abstract: This paper reports the evolution of microstructure and texture in Nickel–Cobalt electrodeposits fabricated by pulse electrodeposition (PED) technique and the correlation of these attributes with the magnetic properties. The structural and microstructural investigation using X-ray diffraction and transmission electron microscopic studies indicate the presence of nanocrystalline grains and nano-twins in the electrodeposits. Convoluted Multiple Whole profile fitting reveals an increase in dislocation density and twin density with increasing cobalt content in the as-deposited samples. Strengthening of <1 1 1> fibre texture and weakening of <2 0 0> fibre texture with increasing cobalt concentration has been observed with X-ray texture analysis. A corresponding significant increase in the saturation magnetization and coercivity observed with increasing cobalt content. A significant improvement in the soft magnetic character in the electrodeposits in terms of increase in saturation magnetization and decrease in coercivity has been observed with thermal annealing.

The effects of anode material type on the optoelectronic properties of electroplated CdTe thin films and the implications for photovoltaic application

Science.gov (United States)

Echendu, O. K.; Dejene, B. F.; Dharmadasa, I. M.

2018-03-01

The effects of the type of anode material on the properties of electrodeposited CdTe thin films for photovoltaic application have been studied. Cathodic electrodeposition of two sets of CdTe thin films on glass/fluorine-doped tin oxide (FTO) was carried out in two-electrode configuration using graphite and platinum anodes. Optical absorption spectra of films grown with graphite anode displayed significant spread across the deposition potentials compared to those grown with platinum anode. Photoelectrochemical cell result shows that the CdTe grown with graphite anode became p-type after post-deposition annealing with prior CdCl2 treatment, as a result of carbon incorporation into the films, while those grown with platinum anode remained n-type after annealing. A review of recent photoluminescence characterization of some of these CdTe films reveals the persistence of a defect level at (0.97-0.99) eV below the conduction band in the bandgap of CdTe grown with graphite anode after annealing while films grown with platinum anode showed the absence of this defect level. This confirms the impact of carbon incorporation into CdTe. Solar cell made with CdTe grown with platinum anode produced better conversion efficiency compared to that made with CdTe grown using graphite anode, underlining the impact of anode type in electrodeposition.

Morphology of uranium electrodeposits on cathode in electrorefining process: A phase-field simulation

International Nuclear Information System (INIS)

Shibuta, Yasushi; Sato, Takumi; Suzuki, Toshio; Ohta, Hirokazu; Kurata, Masaki

2013-01-01

Morphology of uranium electrodeposits on cathode with respect to applied voltage, zirconium concentration in the molten salt and the size of primary deposit during pyroprocessing is systematically investigated by the phase-field simulation. It is found that there is a threshold zirconium concentration in the molten salt demarcating planar and cellular/needle-like electrodeposits, which agrees with experimental results. In addition, the effect of size of primary deposits on the morphology of electrodeposits is examined. It is then confirmed that cellular/needle-like electrodeposits are formed from large primary deposits at all applied voltages considered, whereas both the planar and cellular/needle-like electrodeposits are formed from the primary deposits of 10 μm and less

Oriented hydroxyapatite single crystals produced by the electrodeposition method

Energy Technology Data Exchange (ETDEWEB)

Santos, E.A. dos, E-mail: euler@ufs.br [INSA - Groupe Ingenierie des Surfaces, 24, Bld de la Victoire, 67084 Strasbourg (France); IPCMS - Departement de Surfaces et Interfaces, 23, rue du Loess, BP 43, 67034 Strasbourg (France); Moldovan, M.S. [INSA - Groupe Ingenierie des Surfaces, 24, Bld de la Victoire, 67084 Strasbourg (France); IPCMS - Departement de Surfaces et Interfaces, 23, rue du Loess, BP 43, 67034 Strasbourg (France); Jacomine, L. [INSA - Groupe Ingenierie des Surfaces, 24, Bld de la Victoire, 67084 Strasbourg (France); Mateescu, M. [IS2M - Equipe Interaction Surface-Matiere Vivant, 15, rue Jean Starcky, BP 2488, 68057 Mulhouse (France); Werckmann, J. [IPCMS - Departement de Surfaces et Interfaces, 23, rue du Loess, BP 43, 67034 Strasbourg (France); Anselme, K. [IS2M - Equipe Interaction Surface-Matiere Vivant, 15, rue Jean Starcky, BP 2488, 68057 Mulhouse (France); Mille, P.; Pelletier, H. [INSA - Groupe Ingenierie des Surfaces, 24, Bld de la Victoire, 67084 Strasbourg (France)

2010-05-25

We propose here the use of cathodic electrodeposition as tool to fabricate implant coatings consisting in nano/micro single crystals of hydroxyapatite (HA), preferentially orientated along the c-axis. Coating characterization is the base of this work, where we discuss the mechanisms related to the deposition of oriented hydroxyapatite thin films. It is shown that when deposited on titanium alloys, the HA coating is constituted by two distinct regions with different morphologies: at a distance of few microns from the substrate, large HA single crystals are oriented along the c-axis and appear to grow up from a base material, consisting in an amorphous HA. This organized system has a great importance for cell investigation once the variables involved in the cell/surface interaction are reduced. The use of such systems could give a new insight on the effect of particular HA orientation on the osteoblast cells.

Cyclic Voltammetric Study of High Speed Silver Electrodeposition and Dissolution in Low Cyanide Solutions

Directory of Open Access Journals (Sweden)

Bo Zheng

2016-01-01

Full Text Available The electrochemical processes in solutions with a much lower amount of free cyanide (<10 g/L KCN than the conventional alkaline silver electrolytes were first explored by using cyclic voltammetry. The electrochemical behavior and the effect of KAg(CN2, KCN, and KNO3 electrolytes and solution pH on the electrodeposition and dissolution processes were investigated. Moreover, suitable working conditions for high speed, low cyanide silver electrodeposition were also proposed. Both silver and cyanide ions concentration had significant effects on the electrode polarization and deposition rate. The onset potential of silver electrodeposition could be shifted to more positive values by using solutions containing higher silver and lower KCN concentration. Higher silver concentration also led to higher deposition rate. Besides maintaining high conductivity of the solution, KNO3 might help reduce the operating current density required for silver electrodeposition at high silver concentration albeit at the expense of slowing down the electrodeposition rate. The silver dissolution consists of a limiting step and the reaction rate depends on the amount of free cyanide ions. The surface and material characteristics of Ag films deposited by low cyanide solution are also compared with those deposited by conventional high cyanide solution.

Solid-state electrochemiluminescence sensor through the electrodeposition of Ru(bpy){sub 3}{sup 2+}/AuNPs/chitosan composite film onto electrode

Energy Technology Data Exchange (ETDEWEB)

Yun Wen; Xu Ying; Dong Ping; Ma Xiongxiong [Department of Chemistry, East China Normal University, ZhongShan Road North 3663, Shanghai 20062 (China); He Pingang [Department of Chemistry, East China Normal University, ZhongShan Road North 3663, Shanghai 20062 (China)], E-mail: pghe@chem.ecnu.edu.cn; Fang Yuzhi [Department of Chemistry, East China Normal University, ZhongShan Road North 3663, Shanghai 20062 (China)], E-mail: yuzhi@online.sh.cn

2009-03-02

Tris(2,2'-bipyridyl)ruthenium(II) (Ru(bpy){sub 3}{sup 2+}) has been successfully immobilized onto electrode through the electrodeposition of Ru(bpy){sub 3}{sup 2+}/AuNPs/chitosan composite film. In the experiments, chitosan solution was first mixed with Au nanoparticles (AuNPs) and Ru(bpy){sub 3}{sup 2+}. Then, during chronopotentiometry experiments in this mixed solution, a porous 3D network structured film containing Ru(bpy){sub 3}{sup 2+}, AuNPs and chitosan has been electrodeposited onto cathode due to the deposition of chitosan when pH value is over its pK{sub a} (6.3). The applied current density is crucial to the film thickness and the amount of the entrapped Ru(bpy){sub 3}{sup 2+}. Additionally, these doping Ru(bpy){sub 3}{sup 2+} in the composite film maintained their intrinsic electrochemical and electrochemiluminescence activities. Consequently, this Ru(bpy){sub 3}{sup 2+}/AuNPs/chitosan modified electrode has been used in ECL to detect tripropylamine, and the detection limit was 5 x 10{sup -10} M.

Study of photon interactions and shielding properties of silicate glasses containing Bi2O3, BaO and PbO in the energy region of 1 keV to 100 GeV

International Nuclear Information System (INIS)

Chanthima, N.; Kaewkhao, J.; Limsuwan, P.

2012-01-01

Highlights: ► Interaction photon with of silicate glasses containing PbO, BaO and Bi 2 O 3 studied. ► All interactions were changed with energy and composition of glasses. ► Shielding properties of glasses are better than some standard shielding materials. - Abstract: The mass attenuation coefficient (μ/ρ), effective atomic number (Z eff ), effective electron density (N e,eff ) and half-value layer (HVL) of xR m O n :(1 − x)SiO 2 glass system (where R m O n are Bi 2 O 3 , PbO and BaO, with 0.3 ⩽ x ⩽ 0.7 is fraction by weight) have been calculated by theoretical approach using WinXCom program in the energy region from 1 keV to 100 GeV. Also, the HVL of these glass samples has been compared with some standard shielding concretes. The variations of μ/ρ, Z eff , N e,eff and HVL with energy are shown graphically only for total photon interaction. It has been observed that the value of these parameters has been changed with energy and composition of the silicate glasses. The better shielding properties of glass samples were obtained compared with some standard shielding concretes. These results indicated that glasses in the present study can be used as radiation shielding materials.