WorldWideScience

Sample records for tin oxide sno2

  1. Effect of applied voltage on the structural properties of SnO2 nanostuctures grown on indium-tin-oxide coated glass substrates.

    Science.gov (United States)

    Lee, Dea Uk; Yun, Dong Yeol; No, Young Soo; Hwang, Jun Ho; Lee, Chang Hun; Kim, Tae Whan

    2013-11-01

    SnO2 nanostuctures were formed on indium-tin-oxide (ITO)-coated glass substrates by using an electrochemical deposition (ECD) method. X-ray photoelectron spectroscopy (XPS) spectra showed the existence of elemental Sn and O in the samples, indicative of the formation of SnO2 materials. An XPS spectrum showing the O 1s peak at a binding energy of 531.5 eV indicated that the oxygen atoms were bonded to the SnO2. Field-emission scanning electron microscopy (FE-SEM) images showed that the samples formed by using the ECD method had SnO2 nanostructures with a size between 280 and 350 nm. FE-SEM images showed that the size of the SnO2 nanostructures formed at 65 degrees C for 30 min increased with decreasing applied voltage. X-ray diffraction (XRD) patterns showed that the SnO2 nanostrucures had tetragonal structures with cell parameters of a = 4.738 A and c = 3.187 A. XRD results showed that the peak intensity of the (110) plane increased with decreasing applied voltage, indicative of a preferencial orientation of the (110) plane.

  2. The role of Tin Oxide Concentration on The X-ray Diffraction, Morphology and Optical Properties of In2O3:SnO2 Thin Films

    Science.gov (United States)

    Hasan, Bushra A.; Abdallah, Rusul M.

    2018-05-01

    Alloys were performed from In2O3 doped SnO2 with different doping ratio by quenching from the melt technique. Pulsed Laser Deposition PLD was used to deposit thin films of different doping ratio In2O3 : SnO2 (0, 1, 3, 5, 7 and 9 % wt.) on glass substrate at ambient temperature under vacuum of 10-3 bar thickness of ∼100nm. The structural type,grain size and morphology of the prepared alloys compounds and thin films were examined using X-ray diffraction and atomic force microscopy. The results showed that all alloys have polycrystalline structures and the peaks belonged to the preferred plane for crystal growth were identical with the ITO (Indium – TinOxide) standard cards also another peaks were observed belonged to SnO2 phase. The structures of thin films was also polycrystalline, and the predominate peaks are identical with standard cards ITO. On the other side the prepared thin films declared decrease a reduction of degree of crystallinity with the increase of doping ratio. Atomic Force Microscopy AFM measurements showed the average grain size and average surface roughness exhibit to change in systematic manner with the increase of doping ratio with tin oxide. The optical measurements show that the In2O3:SnO2 thin films have a direct energy gap Eg opt in the first stage decreases with the increase of doping ratio and then get to increase with further increase of doping ration, whereas reverse to that the optical constants such as refractive index (n), extinction coefficient (k) and dielectric constant (εr, εi) have a regular increase with the doping ratio by tin oxide and then decreases.

  3. Nanocrystalline SnO2 formation by oxygen ion implantation in tin thin films

    Science.gov (United States)

    Kondkar, Vidya; Rukade, Deepti; Kanjilal, Dinakar; Bhattacharyya, Varsha

    2018-03-01

    Metallic tin thin films of thickness 100 nm are deposited on fused silica substrates by thermal evaporation technique. These films are implanted with 45 keV oxygen ions at fluences ranging from 5 × 1015 to 5 × 1016 ions cm-2. The energy of the oxygen ions is calculated using SRIM in order to form embedded phases at the film-substrate interface. Post-implantation, films are annealed using a tube furnace for nanocrystalline tin oxide formation. These films are characterized using x-ray diffraction, Raman spectroscopy, UV-vis spectroscopy and photoluminescence spectroscopy. XRD and Raman spectroscopy studies reveal the formation of single rutile phase of SnO2. The size of the nanocrystallites formed decreases with an increase in the ion fluence. The nanocrystalline SnO2 formation is also confirmed by UV-vis and photoluminescence spectroscopy.

  4. Sn powder as reducing agents and SnO2 precursors for the synthesis of SnO2-reduced graphene oxide hybrid nanoparticles.

    Science.gov (United States)

    Chen, Mingxi; Zhang, Congcong; Li, Lingzhi; Liu, Yu; Li, Xichuan; Xu, Xiaoyang; Xia, Fengling; Wang, Wei; Gao, Jianping

    2013-12-26

    A facile approach to prepare SnO2/rGO (reduced graphene oxide) hybrid nanoparticles by a direct redox reaction between graphene oxide (GO) and tin powder was developed. Since no acid was used, it is an environmentally friendly green method. The SnO2/rGO hybrid nanoparticles were characterized by ultraviolet-visible spectroscopy, Raman spectroscopy, thermogravimetric analysis, X-ray diffraction analysis, and X-ray photoelectron spectroscopy. The microstructure of the SnO2/rGO was observed with scanning electron microscopy and transmission electron microscopy. The tin powder efficiently reduced GO to rGO, and the Sn was transformed to SnO2 nanoparticles (∼45 nm) that were evenly distributed on the rGO sheets. The SnO2/rGO hybrid nanoparticles were then coated on an interdigital electrode to fabricate a humidity sensor, which have an especially good linear impedance response from 11% to 85% relative humidity.

  5. Optical band-edge absorption of oxide compound SnO2

    International Nuclear Information System (INIS)

    Roman, L.S.; Valaski, R.; Canestraro, C.D.; Magalhaes, E.C.S.; Persson, C.; Ahuja, R.; Silva, E.F. da; Pepe, I.; Silva, A. Ferreira da

    2006-01-01

    Tin oxide (SnO 2 ) is an important oxide for efficient dielectrics, catalysis, sensor devices, electrodes and transparent conducting coating oxide technologies. SnO 2 thin film is widely used in glass applications due to its low infra-red heat emissivity. In this work, the SnO 2 electronic band-edge structure and optical properties are studied employing a first-principle and fully relativistic full-potential linearized augmented plane wave (FPLAPW) method within the local density approximation (LDA). The optical band-edge absorption α(ω) of intrinsic SnO 2 is investigated experimentally by transmission spectroscopy measurements and their roughness in the light of the atomic force microscopy (AFM) measurements. The sample films were prepared by spray pyrolysis deposition method onto glass substrate considering different thickness layers. We found for SnO 2 qualitatively good agreement of the calculated optical band-gap energy as well as the optical absorption with the experimental results

  6. On the electrochemistry of tin oxide coated tin electrodes in lithium-ion batteries

    International Nuclear Information System (INIS)

    Böhme, Solveig; Edström, Kristina; Nyholm, Leif

    2015-01-01

    As tin based electrodes are of significant interest in the development of improved lithium-ion batteries it is important to understand the associated electrochemical reactions. In this work it is shown that the electrochemical behavior of SnO_2 coated tin electrodes can be described based on the SnO_2 and SnO conversion reactions, the lithium tin alloy formation and the oxidation of tin generating SnF_2. The CV, XPS and SEM data, obtained for electrodeposited tin crystals on gold substrates, demonstrates that the capacity loss often observed for SnO_2 is caused by the reformed SnO_2 layer serving as a passivating layer protecting the remaining tin. Capacities corresponding up to about 80 % of the initial SnO_2 capacity could, however, be obtained by cycling to 3.5 V vs. Li"+/Li. It is also shown that the oxidation of the lithium tin alloy is hindered by the rate of the diffusion of lithium through a layer of tin with increasing thickness and that the irreversible oxidation of tin to SnF_2 at potentials larger than 2.8 V vs. Li"+/Li is due to the fact that SnF_2 is formed below the SnO_2 layer. This improved electrochemical understanding of the SnO_2/Sn system should be valuable in the development of tin based electrodes for lithium-ion batteries.

  7. Improved lithium cyclability and storage in mesoporous SnO2 electronically wired with very low concentrations (≤1 %) of reduced graphene oxide.

    Science.gov (United States)

    Shiva, Konda; Rajendra, H B; Subrahmanyam, K S; Bhattacharyya, Aninda J; Rao, C N R

    2012-04-10

    On the wire: Mesoporous tin dioxide (SnO(2)) wired with very low amounts (≤1 %) of reduced graphene oxide (rGO) exhibits a remarkable improvement in lithium-ion battery performance over bare mesoporous or solid nanoparticles of SnO(2). Reversible lithium intercalation into SnO(2)/SnO over several cycles was demonstrated in addition to conventional reversible lithium storage by an alloying reaction. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Low-debris, efficient laser-produced plasma extreme ultraviolet source by use of a regenerative liquid microjet target containing tin dioxide (SnO2) nanoparticles

    Science.gov (United States)

    Higashiguchi, Takeshi; Dojyo, Naoto; Hamada, Masaya; Sasaki, Wataru; Kubodera, Shoichi

    2006-05-01

    We demonstrated a low-debris, efficient laser-produced plasma extreme ultraviolet (EUV) source by use of a regenerative liquid microjet target containing tin-dioxide (SnO2) nanoparticles. By using a low SnO2 concentration (6%) solution and dual laser pulses for the plasma control, we observed the EUV conversion efficiency of 1.2% with undetectable debris.

  9. Low-debris, efficient laser-produced plasma extreme ultraviolet source by use of a regenerative liquid microjet target containing tin dioxide (SnO2) nanoparticles

    International Nuclear Information System (INIS)

    Higashiguchi, Takeshi; Dojyo, Naoto; Hamada, Masaya; Sasaki, Wataru; Kubodera, Shoichi

    2006-01-01

    We demonstrated a low-debris, efficient laser-produced plasma extreme ultraviolet (EUV) source by use of a regenerative liquid microjet target containing tin-dioxide (SnO 2 ) nanoparticles. By using a low SnO 2 concentration (6%) solution and dual laser pulses for the plasma control, we observed the EUV conversion efficiency of 1.2% with undetectable debris

  10. Characterization of tin oxide nanoparticles synthesized via oxidation from metal

    International Nuclear Information System (INIS)

    Abruzzi, R.C.; Dedavid, B.A.; Pires, M.J.R.; Streicher, M.

    2014-01-01

    The tin oxide (SnO_2) is a promising material with great potential for applications such as gas sensors and catalysts. This oxide nanostructures show higher activation efficiency due to its larger effective surface. This paper presents the synthesis and characterization of the tin oxide in different conditions, via oxidation of pure tin with nitric acid. Results obtained from the characterization of SnO_2 powder by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Particle size by Dynamic Light Scattering (DLS) and Infrared Spectroscopy (FTIR) indicated that the conditions were suitable for the synthesis to obtain manometric tin oxide granules with crystalline structure of rutile. (author)

  11. Synthesis and photocatalytic properties of different SnO2 microspheres on graphene oxide sheets

    International Nuclear Information System (INIS)

    Wei, Jia; Xue, Shaolin; Xie, Pei; Zou, Rujia

    2016-01-01

    Highlights: • Different SnO 2 microspheres were grown on GOs by hydrothermal method. • The morphology was influenced by volume ratio of ethanol and concentrations of precursor. • The shape of SnO 2 microspheres looks like dandelion. • The photocatalytic property is strongly influenced by the SnO 2 morphology on GOs. - Abstract: Different SnO 2 microspheres like dandelions, silkworm cocoons and urchins have been synthesized on graphene oxide sheets (GOs) by hydrothermal method at 190 °C for 24 h. The morphologies, structures, chemical compositions and optical properties of the as-grown SnO 2 microspheres on GOs (SMGs) were characterized by X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), X-ray energy dispersive spectrometer (EDS), Raman spectra and UV–vis diffuse reflectance spectra (DRS) techniques. The results of XRD revealed that the as-grown SnO 2 microspheres have tetragonal rutile structure. The results of Raman spectra, EDS, XRD, XPS and SEM showed that the SnO 2 microspheres were grown on GOs and the average diameter of dandelion-like microsphere was about 1.5 μm. The formation mechanism of SnO 2 microspheres grown on GOs was discussed. The photocatalytic activity of the SMGs composites was evaluated by photocatalytic degradation of Rhodamine B (Rh B) aqueous solution under visible light irradiation. The photocatalytic results showed that the dandelion-like SMGs exhibited a much better photocatalytic activity than those of smooth and rough SMGs.

  12. Ultrathin SnO2 nanosheets: Oriented attachment mechanism, nonstoichiometric defects and enhanced Lithium-ion battery performances

    DEFF Research Database (Denmark)

    Wang, Cen; Du, Gaohui; Ståhl, Kenny

    2012-01-01

    investigations of tin oxides as well as their intertransition processes. Finally, we investigated the lithium-ion storage of the SnO2 NSs as compared to SnO2 hollow spheres and NPs. The results showed superior performance of SnO2 NSs sample over its two counterparts. This greatly enhanced Li-ion storage...

  13. Synthesis and photocatalytic properties of different SnO2 microspheres on graphene oxide sheets

    Science.gov (United States)

    Wei, Jia; Xue, Shaolin; Xie, Pei; Zou, Rujia

    2016-07-01

    Different SnO2 microspheres like dandelions, silkworm cocoons and urchins have been synthesized on graphene oxide sheets (GOs) by hydrothermal method at 190 °C for 24 h. The morphologies, structures, chemical compositions and optical properties of the as-grown SnO2 microspheres on GOs (SMGs) were characterized by X-ray diffractometer (XRD), X-ray photoelectron spectroscopy (XPS), scanning electron microscope (SEM), X-ray energy dispersive spectrometer (EDS), Raman spectra and UV-vis diffuse reflectance spectra (DRS) techniques. The results of XRD revealed that the as-grown SnO2 microspheres have tetragonal rutile structure. The results of Raman spectra, EDS, XRD, XPS and SEM showed that the SnO2 microspheres were grown on GOs and the average diameter of dandelion-like microsphere was about 1.5 μm. The formation mechanism of SnO2 microspheres grown on GOs was discussed. The photocatalytic activity of the SMGs composites was evaluated by photocatalytic degradation of Rhodamine B (Rh B) aqueous solution under visible light irradiation. The photocatalytic results showed that the dandelion-like SMGs exhibited a much better photocatalytic activity than those of smooth and rough SMGs.

  14. Effect of phase interaction on catalytic CO oxidation over the SnO_2/Al_2O_3 model catalyst

    International Nuclear Information System (INIS)

    Chai, Shujing; Bai, Xueqin; Li, Jing; Liu, Cheng; Ding, Tong; Tian, Ye; Liu, Chang; Xian, Hui; Mi, Wenbo; Li, Xingang

    2017-01-01

    Highlights: • Activity for CO oxidation is greatly enhanced by interaction between SnO_2 and Al_2O_3. • Interaction between SnO_2 and Al_2O_3 phases can generate oxygen vacancies. • Oxygen vacancies play an import role for catalytic CO oxidation. • Sn"4"+ cations are the effective sites for catalytic CO oxidation. • Langmuir-Hinshelwood model is preferred for catalytic CO oxidation. - Abstract: We investigated the catalytic CO oxidation over the SnO_2/Al_2O_3 model catalysts. Our results show that interaction between the Al_2O_3 and SnO_2 phases results in the significantly improved catalytic activity because of the formation of the oxygen vacancies. The oxygen storage capacity of the SnO_2/Al_2O_3 catalyst prepared by the physically mixed method is nearly two times higher than that of the SnO_2, which probably results from the change of electron concentration on the interface of the SnO_2 and Al_2O_3 phases. Introducing water vapor to the feeding gas would a little decrease the activity of the catalysts, but the reaction rate could completely recover after removal of water vapor. The kinetics results suggest that the surface Sn"4"+ cations are effective CO adsorptive sites, and the surface adsorbed oxygen plays an important role upon CO oxidation. The reaction pathways upon the SnO_2-based catalysts for CO oxidation follow the Langmuir-Hinshelwood model.

  15. Obtainment of SnO2 for utilization of sensors by coprecipitation of tin salts

    International Nuclear Information System (INIS)

    Masetto, S.R.; Longo, E.

    1990-01-01

    Niobia doped tin dioxide was prepared by precipitation of tin dioxide II and IV using ammonium hydroxide. The powders were characterized by X-ray diffraction, particle size distribution and infra-red spectroscopy. (author) [pt

  16. Effect of solvent on the synthesis of SnO_2 nanoparticles

    International Nuclear Information System (INIS)

    Kumar, Virender; Singh, Karamjit; Singh, Kulwinder; Kumar, Akshay; Kumari, Sudesh; Thakur, Anup

    2016-01-01

    Tin oxide (SnO_2) nanoparticles have been synthesized by co-precipitation method. The synthesized nanoparticles have been characterized by X-ray diffraction (XRD) and Ultraviolet-Visible spectroscopy (UV-VIS). XRD analysis confirmed the formation of single phase of SnO_2 nanoparticles. It has been found that solvents played important role in controlling the crystallite size of SnO_2 nanoparticles. The XRD analysis showed well crystallized tetragonal SnO_2 nanoparticles. The crystallite size of SnO_2 nanoparticles varies with the solvent. Tauc plot showed that optical band gap was also tailored by controlling the solvent during synthesis.

  17. Finely Tuned SnO2 Nanoparticles for Efficient Detection of Reducing and Oxidizing Gases: The Influence of Alkali Metal Cation on Gas-Sensing Properties.

    Science.gov (United States)

    Lee, Szu-Hsuan; Galstyan, Vardan; Ponzoni, Andrea; Gonzalo-Juan, Isabel; Riedel, Ralf; Dourges, Marie-Anne; Nicolas, Yohann; Toupance, Thierry

    2018-03-28

    Tin dioxide (SnO 2 ) nanoparticles were straightforwardly synthesized using an easily scaled-up liquid route that involves the hydrothermal treatment, either under acidic or basic conditions, of a commercial tin dioxide particle suspension including potassium counterions. After further thermal post-treatment, the nanomaterials have been thoroughly characterized by Fourier transform infrared and Raman spectroscopy, powder X-ray diffraction, transmission electron microscopy, X-ray photoelectron spectroscopy, and nitrogen sorption porosimetry. Varying pH conditions and temperature of the thermal treatment provided cassiterite SnO 2 nanoparticles with crystallite sizes ranging from 7.3 to 9.7 nm and Brunauer-Emmett-Teller surface areas ranging from 61 to 106 m 2 ·g -1 , acidic conditions favoring potassium cation removal. Upon exposure to a reducing gas (H 2 , CO, and volatile organic compounds such as ethanol and acetone) or oxidizing gas (NO 2 ), layers of these SnO 2 nanoparticles led to highly sensitive, reversible, and reproducible responses. The sensing results were discussed in regard to the crystallite size, specific area, valence band energy, Debye length, and chemical composition. Results highlight the impact of the counterion residuals, which affect the gas-sensing performance to an extent much higher than that of size and surface area effects. Tin dioxide nanoparticles prepared under acidic conditions and calcined in air showed the best sensing performances because of lower amount of potassium cations and higher crystallinity, despite the lower surface area.

  18. SnO2/Reduced Graphene Oxide Nanocomposite as Anode Material for Lithium-Ion Batteries with Enhanced Cyclability.

    Science.gov (United States)

    Jiang, Wenjuan; Zhao, Xike; Ma, Zengsheng; Lin, Jianguo; Lu, Chunsheng

    2016-04-01

    SnO2 is considered as one of the most promising anode materials for next generation lithium-ion batteries, however, how to build energetic SnO2-based electrode architectures has still remained a big challenge. In this article, we developed a facile method to prepare SnO2/reduced graphene oxide (RGO) nanocomposite for an anode material of lithium-ion batteries. It is shown that, at the current density of 0.25 A.g-1, SnO2/RGO has a high initial capacity of 1705 mAh.g-1 and a capacity retention of 500 mAh . g-1 after 50 cycles. The total specific capacity of SnO2/RGO is higher than the sum of their pure counterparts, indicating a positive synergistic effect on the electrochemical performance.

  19. In situ synthesized SnO2 nanorod/reduced graphene oxide low-dimensional structure for enhanced lithium storage.

    Science.gov (United States)

    Zhang, Wei; Xiao, Xuezhang; Zhang, Yiwen; Li, Junpeng; Zhong, Jiayi; Li, Meng; Fan, Xiulin; Wang, Chuntao; Chen, Lixin

    2018-03-09

    A unique SnO 2 nanorod (NR)/reduced graphene oxide (RGO) composite morphology has been synthesized using the in situ hydrothermal method, for use as an anode material in lithium-ion batteries. The SnO 2 NR adhering to the RGO exhibits a length of 250-400 nm and a diameter of 60-80 nm without any obvious aggregation. The initial discharge/charge capacities of the SnO 2 NR/RGO composite are 1761.3 mAh g -1 and 1233.1 mAh g -1 , with a coulombic efficiency (CE) of 70% under a current density of 200 mA g -1 , and a final capacity of 1101 mAh g -1 after 50 cycles. The rate capability of the SnO 2 NR/RGO is also improved compared to that of bare SnO 2 NR. The superior electrochemical performance is ascribed to the special morphology of the SnO 2 NRs-which plays a role in shorting the transmission path-and the sheet-like 2D graphene, which prevents the agglomeration of SnO 2 and enhances conductivity during the electrochemical reaction of SnO 2 NR/RGO.

  20. In situ synthesized SnO2 nanorod/reduced graphene oxide low-dimensional structure for enhanced lithium storage

    Science.gov (United States)

    Zhang, Wei; Xiao, Xuezhang; Zhang, Yiwen; Li, Junpeng; Zhong, Jiayi; Li, Meng; Fan, Xiulin; Wang, Chuntao; Chen, Lixin

    2018-03-01

    A unique SnO2 nanorod (NR)/reduced graphene oxide (RGO) composite morphology has been synthesized using the in situ hydrothermal method, for use as an anode material in lithium-ion batteries. The SnO2 NR adhering to the RGO exhibits a length of 250-400 nm and a diameter of 60-80 nm without any obvious aggregation. The initial discharge/charge capacities of the SnO2 NR/RGO composite are 1761.3 mAh g-1 and 1233.1 mAh g-1, with a coulombic efficiency (CE) of 70% under a current density of 200 mA g-1, and a final capacity of 1101 mAh g-1 after 50 cycles. The rate capability of the SnO2 NR/RGO is also improved compared to that of bare SnO2 NR. The superior electrochemical performance is ascribed to the special morphology of the SnO2 NRs—which plays a role in shorting the transmission path—and the sheet-like 2D graphene, which prevents the agglomeration of SnO2 and enhances conductivity during the electrochemical reaction of SnO2 NR/RGO.

  1. SnO2 Quantum Dots@Graphene Oxide as a High-Rate and Long-Life Anode Material for Lithium-Ion Batteries.

    Science.gov (United States)

    Zhao, Kangning; Zhang, Lei; Xia, Rui; Dong, Yifan; Xu, Wangwang; Niu, Chaojiang; He, Liang; Yan, Mengyu; Qu, Longbin; Mai, Liqiang

    2016-02-03

    Tin-based electrode s offer high theoretical capacities in lithium ion batteries, but further commercialization is strongly hindered by the poor cycling stability. An in situ reduction method is developed to synthesize SnO2 quantum dots@graphene oxide. This approach is achieved by the oxidation of Sn(2+) and the reduction of the graphene oxide. At 2 A g(-1), a capacity retention of 86% is obtained even after 2000 cycles. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  2. Rapid synthesis of tin oxide nanostructures by microwave-assisted thermal oxidation for sensor applications

    Science.gov (United States)

    Phadungdhitidhada, S.; Ruankham, P.; Gardchareon, A.; Wongratanaphisan, D.; Choopun, S.

    2017-09-01

    In the present work nanostructures of tin oxides were synthesized by a microwave-assisted thermal oxidation. Tin precursor powder was loaded into a cylindrical quartz tube and further radiated in a microwave oven. The as-synthesized products were characterized by scanning electron microscope, transmission electron microscope, and x-ray diffractometer. The results showed that two different morphologies of SnO2 microwires (MWs) and nanoparticles (NPs) were obtained in one minute of microwave radiation under atmospheric ambient. A few tens of the SnO2 MWs with the length of 10-50 µm were found. Some parts of the MWs were decorated with the SnO2 NPs. However, most of the products were SnO2 NPs with the diameter ranging from 30-200 nm. Preparation under loosely closed system lead to mixed phase SnO-SnO2 NPs with diameter of 30-200 nm. The single-phase of SnO2 could be obtained by mixing the Sn precursor powders with CuO2. The products were mostly found to be SnO2 nanowires (NWs) and MWs. The diameter of SnO2 NWs was less than 50 nm. The SnO2 NPs, MWs, and NWs were in the cassiterite rutile structure phase. The SnO NPs was in the tetragonal structure phase. The growth direction of the SnO2 NWs was observed in (1 1 0) and (2 2 1) direction. The ethanol sensor performance of these tin oxide nanostructures showed that the SnO-SnO2 NPs exhibited extremely high sensitivity. Invited talk at 5th Thailand International Nanotechnology Conference (Nano Thailand-2016), 27-29 November 2016, Nakhon Ratchasima, Thailand.

  3. Hydrolysis of bis(dimethylamido)tin to tin (II) oxyhydroxide and its selective transformation into tin (II) or tin (IV) oxide

    KAUST Repository

    Khanderi, Jayaprakash

    2015-03-01

    Sn6O4(OH)4, a hydrolysis product of Sn(NMe2)2, is transformed to tin (II) or tin (IV) oxide by solid and solution phase processing. Tin (II) oxide is formed by heating Sn6O4(OH)4 at ≤200 °C in air or under inert atmosphere. Tin (IV) oxide nanoparticles are formed in the presence of a carboxylic acid and base in air at room temperature. IR spectroscopy, Raman spectroscopy, thermogravimetry (coupled with infrared spectroscopy), powder X-ray diffraction, high temperature X-ray diffraction, scanning electron and transmission electron microscopy are used for the characterization of Sn6O4(OH)4 and the investigation of its selective decomposition into SnO or SnO2. Spectroscopic and X-ray diffraction results indicate that SnO is formed by the removal of water from crystalline Sn6O4(OH)4. SEM shows octahedral morphology of the Sn6O4(OH)4, SnO and SnO2 with particle size from 400 nm-2 μm during solid state conversion. Solution phase transformation of Sn6O4(OH)4 to SnO2 occurs in the presence of potassium glutarate and oxygen. SnO2 particles are 15-20 nm in size.

  4. Combinatorial study of zinc tin oxide thin-film transistors

    Science.gov (United States)

    McDowell, M. G.; Sanderson, R. J.; Hill, I. G.

    2008-01-01

    Groups of thin-film transistors using a zinc tin oxide semiconductor layer have been fabricated via a combinatorial rf sputtering technique. The ZnO :SnO2 ratio of the film varies as a function of position on the sample, from pure ZnO to SnO2, allowing for a study of zinc tin oxide transistor performance as a function of channel stoichiometry. The devices were found to have mobilities ranging from 2to12cm2/Vs, with two peaks in mobility in devices at ZnO fractions of 0.80±0.03 and 0.25±0.05, and on/off ratios as high as 107. Transistors composed predominantly of SnO2 were found to exhibit light sensitivity which affected both the on/off ratios and threshold voltages of these devices.

  5. An easy two-step microwave assisted synthesis of SnO2/CNT hybrids

    CSIR Research Space (South Africa)

    Motshekga, SC

    2011-11-01

    Full Text Available Tin oxide (SnO2) - decorated carbon nanotube (CNT) heterostructures were synthesized by microwave assisted wet impregnation method. CNTs of three different aspect ratios were compared. The hybrid samples were characterized by powder X...

  6. Developing the photovoltaic performance of dye-sensitized solar cells (DSSCs) using a SnO2-doped graphene oxide hybrid nanocomposite as a photo-anode

    Science.gov (United States)

    Sasikumar, Ragu; Chen, Tse-Wei; Chen, Shen-Ming; Rwei, Syang-Peng; Ramaraj, Sayee Kannan

    2018-05-01

    Tin(IV) oxide nanoparticles (SnO2 NPs) doped on the surface of graphene oxide (GO) sheets for application in Dye-Sensitized Solar Cells (DSSCs). The effective incorporation of SnO2 on the surface of GO sheets were confirmed by powder X-ray diffraction (PXRD), Fourier transform infra-red spectroscopy (FT-IR), thermogravimetric analysis (TGA), electrochemical impedance spectroscopy (EIS), and Raman spectroscopy. The morphology of the GO/SnO2 hybrid nanocomposite was confirmed by field emission scanning electron microscopy (FE-SEM) analysis. This current study involvement with the effect of different photo-anodes such as GO, SnO2, and GO/SnO2 hybrid nanocomposite on the power conversion efficiency (PCE) of the triiodide electrolyte based DSSCs. Remarkably, GO/SnO2 hybrid nanocomposite based photo-anode for DSSC observed PCE of 8.3% and it is about 12% higher than that of un-doped TiO2 photo-anode. The equivalent short-circuit photocurrent density (Jsc) of 16.67 mA cm-2, open circuit voltage (Voc) of 0.77 V, and fill factor (FF) of 0.65 respectively. The achieved results propose that the hybrid nanocomposite is an appropriate photo-anodic material for DSSCs applications.

  7. Sub-2 nm SnO2 nanocrystals: A reduction/oxidation chemical reaction synthesis and optical properties

    International Nuclear Information System (INIS)

    Zhang Hui; Du Ning; Chen Bindi; Cui Tianfeng; Yang Deren

    2008-01-01

    A simple reduction/oxidation chemical solution approach at room temperature has been developed to synthesize ultrafine SnO 2 nanocrystals, in which NaBH 4 is used as a reducing agent instead of mineralizers such as sodium hydroxide, ammonia, and alcohol. The morphology, structure, and optical property of the ultrafine SnO 2 nanocrystals have been characterized by high-resolution transmission electron microscopy (HRTEM), X-ray powder diffraction (XRD), differential scanning calorimetry and thermogravimetric analysis (DSC-TGA), X-ray photoelectron spectroscopy (XPS) and UV-vis absorption spectroscopy. It is indicated that the uniform tetragonal ultrafine SnO 2 nanocrystals with the size below 2 nm have been fabricated at room temperature. The band gap of the ultrafine SnO 2 nanocrystals is about 4.1 eV, exhibiting 0.5 eV blue shift from that of the bulk SnO 2 (3.6 eV). Furthermore, the mechanism for the reduction/oxidation chemical reaction synthesis of the ultrafine SnO 2 nanocrystals has been preliminary presented

  8. Effect of annealing on the structure of chemically synthesized SnO_2 nanoparticles

    International Nuclear Information System (INIS)

    Singh, Kulwinder; Kumar, Akshay; Kumar, Virender; Vij, Ankush; Kumari, Sudesh; Thakur, Anup

    2016-01-01

    Tin oxide (SnO_2) nanoparticles have been synthesized by co-precipitation method. The synthesized nanoparticles were characterized by X-ray diffraction (XRD) and Raman spectroscopy. XRD analysis confirmed the single phase formation of SnO_2 nanoparticles. The Raman shifts showed the typical feature of the tetragonal phase of the as-synthesized SnO_2 nanoparticles. At low annealing temperature, a strong distortion of the crystalline structure and high degree of agglomeration was observed. It is concluded that the crystallinity of SnO_2 nanoparticles improves with the increase in annealing temperature.

  9. Investigation on Synthesis, Stability, and Thermal Conductivity Properties of Water-Based SnO2/Reduced Graphene Oxide Nanofluids

    Science.gov (United States)

    Yu, Xiaofen; Wu, Qibai; Zhang, Haiyan; Zeng, Guoxun; Li, Wenwu; Qian, Yannan; Li, Yang; Yang, Guoqiang; Chen, Muyu

    2017-01-01

    With the rapid development of industry, heat removal and management is a major concern for any technology. Heat transfer plays a critically important role in many sectors of engineering; nowadays utilizing nanofluids is one of the relatively optimized techniques to enhance heat transfer. In the present work, a facile low-temperature solvothermal method was employed to fabricate the SnO2/reduced graphene oxide (rGO) nanocomposite. X-ray diffraction (XRD), thermogravimetric analysis (TGA), X-ray photoelectron spectroscope (XPS), Raman spectroscopy, and transmission electron microscopy (TEM) have been performed to characterize the SnO2/rGO nanocomposite. Numerous ultrasmall SnO2 nanoparticles with average diameters of 3–5 nm were anchored on the surface of rGO, which contain partial hydrophilic functional groups. Water-based SnO2/rGO nanofluids were prepared with various weight concentrations by using an ultrasonic probe without adding any surfactants. The zeta potential was measured to investigate the stability of the as-prepared nanofluid which exhibited great dispersion stability after quiescence for 60 days. A thermal properties analyzer was employed to measure thermal conductivity of water-based SnO2/rGO nanofluids, and the results showed that the enhancement of thermal conductivity could reach up to 31% at 60 °C under the mass fraction of 0.1 wt %, compared to deionized water. PMID:29280972

  10. Investigation on Synthesis, Stability, and Thermal Conductivity Properties of Water-Based SnO2/Reduced Graphene Oxide Nanofluids

    Directory of Open Access Journals (Sweden)

    Xiaofen Yu

    2017-12-01

    Full Text Available With the rapid development of industry, heat removal and management is a major concern for any technology. Heat transfer plays a critically important role in many sectors of engineering; nowadays utilizing nanofluids is one of the relatively optimized techniques to enhance heat transfer. In the present work, a facile low-temperature solvothermal method was employed to fabricate the SnO2/reduced graphene oxide (rGO nanocomposite. X-ray diffraction (XRD, thermogravimetric analysis (TGA, X-ray photoelectron spectroscope (XPS, Raman spectroscopy, and transmission electron microscopy (TEM have been performed to characterize the SnO2/rGO nanocomposite. Numerous ultrasmall SnO2 nanoparticles with average diameters of 3–5 nm were anchored on the surface of rGO, which contain partial hydrophilic functional groups. Water-based SnO2/rGO nanofluids were prepared with various weight concentrations by using an ultrasonic probe without adding any surfactants. The zeta potential was measured to investigate the stability of the as-prepared nanofluid which exhibited great dispersion stability after quiescence for 60 days. A thermal properties analyzer was employed to measure thermal conductivity of water-based SnO2/rGO nanofluids, and the results showed that the enhancement of thermal conductivity could reach up to 31% at 60 °C under the mass fraction of 0.1 wt %, compared to deionized water.

  11. Atomic-Layer-Deposited SnO2 as Gate Electrode for Indium-Free Transparent Electronics

    KAUST Repository

    Alshammari, Fwzah Hamud; Hota, Mrinal Kanti; Wang, Zhenwei; Aljawhari, Hala; Alshareef, Husam N.

    2017-01-01

    Atomic-layer-deposited SnO2 is used as a gate electrode to replace indium tin oxide (ITO) in thin-film transistors and circuits for the first time. The SnO2 films deposited at 200 °C show low electrical resistivity of ≈3.1 × 10−3 Ω cm with ≈93

  12. OPTIMISATION OF SPRAY DEPOSITED Sno2 THIN FILM FOR ...

    African Journals Online (AJOL)

    Dr Obe

    1987-09-01

    Sep 1, 1987 ... The use of conducting tin-oxide (SnO2 ) films for fabrication of solar cell is becoming ... Attempts have also been made to fabricate Sn2/Si solar cell with the present set up, and .... Photovoltaic Specialists' Conf. Washington ...

  13. Rapid synthesis of tin oxide decorated carbon nanotube nanocomposities as anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Lin, Jeng-Yu; Chou, Ming-Hung; Kuo, Yi-Chen

    2014-01-01

    Highlights: • SnO 2 –CNTs nanocomposite was synthesized by microwave-assisted hydrothermal route. • Adding glucose assisted SnO 2 nanoclusters uniformly grow on the surfaces of CNTs. • SnO 2 –CNTs nanocomposite shows improved electrochemical properties. -- Abstract: In this study, the tin oxide decorated carbon nanotubes (SnO 2 –CNTs) nanocomposites have been successfully synthesized using an ultrafast and environmentally friendly microwave-assisted hydrothermal method. According to X-ray diffraction pattern, field emission scanning electron microscopy and transmission electron microscopy, the SnO 2 nanoclusters can directly grow on the surfaces of CNTs with uniform coverage along the longitudinal axis by using glucose as a binding agent. The electrochemical properties of the SnO 2 –CNTs nanocomposite electrode have been further characterized by galvanostatic discharge/charge cycling tests, cyclic voltammetry and electrochemical impedance spectroscopy. Results demonstrate that the SnO 2 –CNTs nanocomposite electrode exhibited a superior reversible discharge capacity, cycling stability and rate capability as an anode material for Li-ion batteries compared to the pristine SnO 2 electrode. Such synergic improvements can be attributed to combining the SnO 2 nanoclusters onto the conductive CNTs matrix by taking advantage of the relatively high specific capacity of SnO 2 nanoclusters and the excellent cycling capability of the CNTs

  14. Tin-oxide-coated single-walled carbon nanotube bundles supporting platinum electrocatalysts for direct ethanol fuel cells

    International Nuclear Information System (INIS)

    Hsu, Ryan S; Higgins, Drew; Chen Zhongwei

    2010-01-01

    Novel tin-oxide (SnO 2 )-coated single-walled carbon nanotube (SWNT) bundles supporting platinum (Pt) electrocatalysts for ethanol oxidation were developed for direct ethanol fuel cells. SnO 2 -coated SWNT (SnO 2 -SWNT) bundles were synthesized by a simple chemical-solution route. SnO 2 -SWNT bundles supporting Pt (Pt/SnO 2 -SWNTs) electrocatalysts and SWNT-supported Pt (Pt/SWNT) electrocatalysts were prepared by an ethylene glycol reduction method. The catalysts were physically characterized using TGA, XRD and TEM and electrochemically evaluated through cyclic voltammetry experiments. The Pt/SnO 2 -SWNTs showed greatly enhanced electrocatalytic activity for ethanol oxidation in acid medium, compared to the Pt/SWNT. The optimal SnO 2 loading of Pt/SnO 2 -SWNT catalysts with respect to specific catalytic activity for ethanol oxidation was also investigated.

  15. Tin-oxide-coated single-walled carbon nanotube bundles supporting platinum electrocatalysts for direct ethanol fuel cells.

    Science.gov (United States)

    Hsu, Ryan S; Higgins, Drew; Chen, Zhongwei

    2010-04-23

    Novel tin-oxide (SnO(2))-coated single-walled carbon nanotube (SWNT) bundles supporting platinum (Pt) electrocatalysts for ethanol oxidation were developed for direct ethanol fuel cells. SnO(2)-coated SWNT (SnO(2)-SWNT) bundles were synthesized by a simple chemical-solution route. SnO(2)-SWNT bundles supporting Pt (Pt/SnO(2)-SWNTs) electrocatalysts and SWNT-supported Pt (Pt/SWNT) electrocatalysts were prepared by an ethylene glycol reduction method. The catalysts were physically characterized using TGA, XRD and TEM and electrochemically evaluated through cyclic voltammetry experiments. The Pt/SnO(2)-SWNTs showed greatly enhanced electrocatalytic activity for ethanol oxidation in acid medium, compared to the Pt/SWNT. The optimal SnO(2) loading of Pt/SnO(2)-SWNT catalysts with respect to specific catalytic activity for ethanol oxidation was also investigated.

  16. Spray Pyrolyzed Polycrystalline Tin Oxide Thin Film as Hydrogen Sensor

    Directory of Open Access Journals (Sweden)

    Ganesh E. Patil

    2010-09-01

    Full Text Available Polycrystalline tin oxide (SnO2 thin film was prepared by using simple and inexpensive spray pyrolysis technique (SPT. The film was characterized for their phase and morphology by X-ray diffraction (XRD and scanning electron microscopy (SEM, respectively. The crystallite size calculated from the XRD pattern is 84 nm. Conductance responses of the polycrystalline SnO2 were measured towards gases like hydrogen (H2, liquefied petroleum gas (LPG, ethanol vapors (C2H5OH, NH3, CO, CO2, Cl2 and O2. The gas sensing characteristics were obtained by measuring the sensor response as a function of various controlling factors like operating temperature, operating voltages (1 V, 5 V, 10 V 15 V, 20 V and 25 V and concentration of gases. The sensor response measurement showed that the SnO2 has maximum response to hydrogen. Furthermore; the SnO2 based sensor exhibited fast response and good recovery towards hydrogen at temperature 150 oC. The result of response towards H2 reveals that SnO2 thin film prepared by SPT would be a suitable material for the fabrication of the hydrogen sensor.

  17. Facile fabrication of hollow mesosphere of crystalline SnO2 nanoparticles and synthesis of SnO2@SWCNTs@Reduced Graphene Oxide nanocomposite as efficient Pt-Free counter electrode for dye-sensitized solar cells

    Science.gov (United States)

    Khan, Muhammad Wasim; Yao, Jixin; Zhang, Kang; Zuo, Xueqin; Yang, Qun; Tang, Huaibao; Ur Rehman, Khalid Mehmood; Li, Guang; Wu, Mingzai; Zhu, Kerong; Zhang, Haijun

    2018-06-01

    In this research, SnO2@SWCNTs@Reduced Graphene Oxide based nanocomposite was synthesized by a one step hydrothermal method and reported new cost effective platinum-free counter-electrodes (CEs) in dye-sensitized solar cells (DSSCs). The CEs were formed by using the nanocomposites with the help of a pipette using a doctor-blade technique. The efficiency of this nanocomposite revealed significant elctrocatalytic properties upon falling the triiodide, possessing to synergistic effect of SnO2 nano particles and improved conductivity when SWCNTs dispersed on graphene sheet. Therefore, the power conversion efficiency (PCE) of prepared SnO2@SWCNTs@RGO nanocomposite CE attained of (6.1%) in DSSCs which is equivalent to the value (6.2%) which attained to the value (6.2%) with pure Pt CE as a reference. SnO2@SWCNTs@RGO nanocomposite CEs give more stable catalytic activities for triiodide reduction than SnO2 and SWCNTs CEs in the cyclic voltammetry (CV) analysis. Furthermore, to the subsistence of graphene oxide, the nanocomposite acquired both higher stability and efficiency in the nanocomposite.

  18. Realization of ppm-level CO detection with exceptionally high sensitivity using reduced graphene oxide-loaded SnO2 nanofibers with simultaneous Au functionalization.

    Science.gov (United States)

    Kim, Jae-Hun; Katoch, Akash; Kim, Hyoun Woo; Kim, Sang Sub

    2016-03-07

    We have realized the highly sensitive, selective ppm-level carbon monoxide (CO) detection based on graphene oxide (RGO) nanosheets-loaded SnO2 nanofibers with simultaneous Au functionalization. The interplay between RGO/Au and SnO2 in terms of transfer of charge carriers and modulation of potential barriers is responsible for the exceptionally high CO detectability.

  19. Porous SnO2-CuO nanotubes for highly reversible lithium storage

    Science.gov (United States)

    Cheong, Jun Young; Kim, Chanhoon; Jung, Ji-Won; Yoon, Ki Ro; Kim, Il-Doo

    2018-01-01

    Facile synthesis of rationally designed structures is critical to realize a high performance electrode for lithium-ion batteries (LIBs). Among different candidates, tin(IV) oxide (SnO2) is one of the most actively researched electrode materials due to its high theoretical capacity (1493 mAh g-1), abundance, inexpensive costs, and environmental friendliness. However, severe capacity decay from the volume expansion and low conductivity of SnO2 have hampered its use as a feasible electrode for LIBs. Rationally designed SnO2-based nanostructures with conductive materials can be an ideal solution to resolve such limitations. In this work, we have successfully fabricated porous SnO2-CuO composite nanotubes (SnO2-CuO p-NTs) by electrospinning and subsequent calcination step. The porous nanotubular structure is expected to mitigate the volume expansion of SnO2, while the as-formed Cu from CuO upon lithiation allows faster electron transport by improving the low conductivity of SnO2. With a synergistic effect of both Sn and Cu-based oxides, SnO2-CuO p-NTs deliver stable cycling performance (91.3% of capacity retention, ∼538 mAh g-1) even after 350 cycles at a current density of 500 mA g-1, along with enhanced rate capabilities compared with SnO2.

  20. Synthesising highly reactive tin oxide using Tin(II2- ethylhexanoate polynucleation as precursor

    Directory of Open Access Journals (Sweden)

    Alejandra Montenegro Hernández

    2009-01-01

    Full Text Available Tin oxide is a widely used compound in technological applications, particularity as a catalyst, gas sensor and in making varistors, transparent conductors, electrocatalytic electrodes and photovoltaic cells. An ethylhexanoate tin salt, a carboxylic acid and poly-esterification were used for synthesising highly reactive tin oxide in the present study. Synthesis was controlled by Fourier transform infrared (FTIR spectroscopy and recording changes in viscosity. The tin oxide characteristics so obtained were determined using FTIR spectroscopy, X-ray diffraction (XRD and scanning electron microscopy (SEM. The SnO2 dust synthesised and heat-treated at 550°C yielded high density aggregates, having greater than 50 μm particle size. This result demonstrates the high reactivity of the ceramic powders synthesised here.

  1. Incorporation of graphene into SnO2 photoanodes for dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Batmunkh, Munkhbayar; Dadkhah, Mahnaz; Shearer, Cameron J.; Biggs, Mark J.; Shapter, Joseph G.

    2016-01-01

    Graphical abstract: Incorporation of a graphene structure into SnO 2 dye-sensitized solar cell photoanode films has been demonstrated for the first time. The use of graphene in the SnO 2 has been found to be a promising strategy to address many problems of photovoltaic cells based on SnO 2 photoanodes. - Highlights: • SnO 2 -reduced graphene oxide (RGO) hybrid is prepared using a microwave technique. • The first SnO 2 -RGO photoanode based DSSC is fabricated. • Use of RGO addresses the major shortcoming of SnO 2 when employed as a DSSC photoanode. • RGO significantly improved the electron transport rate within the DSSC devices. • Incorporation of RGO into the SnO 2 photoanode enhanced the DSSC efficiency by 91.5%. - Abstract: In dye-sensitized solar cell (DSSC) photoanodes, tin dioxide (SnO 2 ) structures present a promising alternative semiconducting oxide to the conventional titania (TiO 2 ), but they suffer from poor photovoltaic (PV) efficiency caused by insufficient dye adsorption and low energy value of the conduction band. A hybrid structure consisting of SnO 2 and reduced graphene oxide (SnO 2 -RGO) was synthesized via a microwave-assisted method and has been employed as a photoanode in DSSCs. Incorporation of RGO into the SnO 2 photoanode enhanced the power conversion efficiency of DSSC device by 91.5%, as compared to the device assembled without RGO. This efficiency improvement can be attributed to increased dye loading, enhanced electron transfer and addition of suitable energy levels in the photoanode. Finally, the use of RGO addresses the major shortcoming of SnO 2 when employed as a DSSC photoanode, namely poor dye adsorption and slow electron transfer rate.

  2. Assembly of tin oxide/graphene nanosheets into 3D hierarchical frameworks for high-performance lithium storage.

    Science.gov (United States)

    Huang, Yanshan; Wu, Dongqing; Han, Sheng; Li, Shuang; Xiao, Li; Zhang, Fan; Feng, Xinliang

    2013-08-01

    3D hierarchical tin oxide/graphene frameworks (SnO2 /GFs) were built up by the in situ synthesis of 2D SnO2 /graphene nanosheets followed by hydrothermal assembly. These SnO2 /GFs exhibited a 3D hierarchical porous architecture with mesopores (≈3 nm), macropores (3-6 μm), and a large surface area (244 m(2) g(-1) ), which not only effectively prevented the agglomeration of SnO2 nanoparticles, but also facilitated fast ion and electron transport in 3D pathways. As a consequence, the SnO2 /GFs exhibited a high capacity of 830 mAh g(-1) for up to 70 charge-discharge cycles at 100 mA g(-1) . Even at a high current density of 500 mA g(-1) , a reversible capacity of 621 mAh g(-1) could be maintained for SnO2 /GFs with excellent cycling stability. Such performance is superior to that of previously reported SnO2 /graphene and other SnO2 /carbon composites with similar weight contents of SnO2 . Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. TiO2 coated SnO2 nanosheet films for dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Cai Fengshi; Yuan Zhihao; Duan Yueqing; Bie Lijian

    2011-01-01

    TiO 2 -coated SnO 2 nanosheet (TiO 2 -SnO 2 NS) films about 300 nm in thickness were fabricated on fluorine-doped tin oxide glass by a two-step process with facile solution-grown approach and subsequent hydrolysis of TiCl 4 aqueous solution. The as-prepared TiO 2 -SnO 2 NSs were characterized by scanning electron microscopy and X-ray diffraction. The performances of the dye-sensitized solar cells (DSCs) with TiO 2 -SnO 2 NSs were analyzed by current-voltage measurements and electrochemical impedance spectroscopy. Experimental results show that the introduction of TiO 2 -SnO 2 NSs can provide an efficient electron transition channel along the SnO 2 nanosheets, increase the short current density, and finally improve the conversion efficiency for the DSCs from 4.52 to 5.71%.

  4. SnO2/PPy Screen-Printed Multilayer CO2 Gas Sensor

    Directory of Open Access Journals (Sweden)

    S.A. WAGHULEY

    2007-05-01

    Full Text Available Tin dioxide (SnO2 plays a dominant role in solid state gas sensors and exhibit sensitivity towards oxidizing and reducing gases by a variation of its electrical properties. The electrical conducting polymer-polypyrrole (PPy has high anisotropy of electrical conduction and used as a gas sensor. SnO2/PPy multilayer, pure SnO2, pure PPy sensors were prepared by screen-printing method on Al2O3 layer followed by glass substrate. The sensors were used for different concentration (ppm of CO2 gas investigation at room temperature (303 K. The sensitivity of SnO2/PPy multilayer sensor was found to be higher, compared with pure SnO2 and pure PPy sensors. The multilayer sensor exhibited improved stability. The response and recovery time of multilayer sensor were found to be ~2 min and ~10 min respectively.

  5. Facile, low temperature synthesis of SnO_2/reduced graphene oxide nanocomposite as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Hou, Chau-Chung; Brahma, Sanjaya; Weng, Shao-Chieh; Chang, Chia-Chin; Huang, Jow-Lay

    2017-01-01

    Highlights: • Facile, one-pot, low temperature synthesis of SnO_2-RGO composite. • In-situ reduction of graphene oxide and growth of SnO_2 nanoparticle. • Concentration of reductant during synthesis affects the properties significantly. • SnO_2-RGO composite shows good rate capability and stable capacitance. • Synthesis method is energy efficient and scalable for other metal oxides. - Abstract: We demonstrate a facile, single step, low temperature and energy efficient strategy for the synthesis of SnO_2-reduced graphene oxide (RGO) nanocomposite where the crystallization of SnO_2 nanoparticles and the reduction of graphene oxide takes place simultaneously by an in situ chemical reduction process. The electrochemical property of the SnO_2-RGO composite prepared by using low concentrations of reducing agent shows better Li storage performance, good rate capability (378 mAh g"−"1 at 3200 mA g"−"1) and stable capacitance (522 mAh g"−"1 after 50 cycles). Increasing the reductant concentration lead to crystallization of high concentration of SnO_2 nanoparticle aggregation and degrade the Li ion storage property.

  6. Gas Sensing of Fluorine Doped Tin Oxide Thin Films Prepared by Spray Pyrolysis

    Directory of Open Access Journals (Sweden)

    A. A. YADAV

    2008-05-01

    Full Text Available Fluorine doped tin oxide (F: SnO2 films have been prepared onto the amorphous glass substrates by a spray pyrolysis. XRD studies reveal that the material deposited is polycrystalline SnO2 and have tetragonal structure. It is observed that films are highly orientated along (200 direction. The direct optical band gap energy for the F: SnO2 films are found to be 4.15 eV. Gas sensing properties of the sensor were checked against combustible gases like H2, CO2 CO, C3H8, CH4.The H2 sensitivity of the F-doped SnO2 sensor was found to be increased. The increase in the sensitivity is discussed in terms of increased resistivity and reduced permeation of gaseous oxygen into the underlying sensing layer due to the surface modification of the sensor.

  7. Bio-active synthesis of tin oxide nanoparticles using eggshell membrane for energy storage application

    Science.gov (United States)

    Celina Selvakumari, J.; Nishanthi, S. T.; Dhanalakshmi, J.; Ahila, M.; Pathinettam Padiyan, D.

    2018-05-01

    Nano-sized tin oxide (SnO2) particles were synthesized using eggshell membrane (ESM), a natural bio-waste from the chicken eggshell. The crystallization of SnO2 into the tetragonal structure was confirmed from powder X-ray diffraction and the crystallite size ranged from 13 to 40 nm. Various shapes including rod, hexagonal and spherical SnO2 nanoparticles were observed from the morphological studies. The electrochemical impedance study revealed a lower charge transfer resistance (Rct) of 8.565 Ω and the presence of a constant phase element which arised due to surface roughness and porosity. Capacitive behavior seen in the cyclic voltammetry curve of the prepared SnO2 nanoparticles, find future applications in supercapacitors.

  8. Hybrid composite thin films composed of tin oxide nanoparticles and cellulose

    International Nuclear Information System (INIS)

    Mahadeva, Suresha K; Nayak, Jyoti; Kim, Jaehwan

    2013-01-01

    This paper reports the preparation and characterization of hybrid thin films consisting of tin oxide (SnO 2 ) nanoparticles and cellulose. SnO 2 nanoparticle loaded cellulose hybrid thin films were fabricated by a solution blending technique, using sodium dodecyl sulfate as a dispersion agent. Scanning and transmission electron microscopy studies revealed uniform dispersion of the SnO 2 nanoparticles in the cellulose matrix. Reduction in the crystalline melting transition temperature and tensile properties of cellulose was observed due to the SnO 2 nanoparticle loading. Potential application of these hybrid thin films as low cost, flexible and biodegradable humidity sensors is examined in terms of the change in electrical resistivity of the material exposed to a wide range of humidity as well as its response–recovery behavior. (paper)

  9. Nanocrystalline SnO2 thin films: Structural, morphological, electrical transport and optical studies

    International Nuclear Information System (INIS)

    Sakhare, R.D.; Khuspe, G.D.; Navale, S.T.; Mulik, R.N.; Chougule, M.A.; Pawar, R.C.; Lee, C.S.; Sen, Shashwati; Patil, V.B.

    2013-01-01

    Highlights: ► Novel chemical route of synthesis of SnO 2 films. ► Physical properties SnO 2 are influenced by process temperature. ► The room temperature electrical conductivity of SnO 2 is of 10 −7 –10 −5 (Ω cm) −1 . ► SnO 2 exhibit high absorption coefficient (10 4 cm −1 ). -- Abstract: Sol–gel spin coating method has been successfully employed for preparation of nanocrystalline tin oxide (SnO 2 ) thin films. The effect of processing temperature on the structure, morphology, electrical conductivity, thermoelectric power and band gap was studied using X-ray diffraction, field emission scanning electron microscopy, transmission electron microscopy, selected area electron diffraction pattern, atomic force microscopy, two probe technique and UV–visible spectroscopy. X-ray diffraction (XRD) analysis showed that SnO 2 films are crystallized in the tetragonal phase and present a random orientation. Field emission scanning electron microscopy (FESEM) analysis revealed that surface morphology of the tin oxide film consists nanocrystalline grains with uniform coverage of the substrate surface. Transmission electron microscopy (TEM) of SnO 2 film showed nanocrystals having diameter ranging from 5 to 10 nm. Selected area electron diffraction (SAED) pattern confirms tetragonal phase evolution of SnO 2 . Atomic force microscopy (AFM) analysis showed surface morphology of SnO 2 film is smooth. The dc electrical conductivity showed the semiconducting nature with room temperature electrical conductivity increased from 10 −7 to 10 −5 (Ω cm) −1 as processing temperature increased from 400 to 700 °C. Thermo power measurement confirms n-type conduction. The band gap energy of SnO 2 film decreased from 3.88 to 3.60 eV as processing temperature increased from 400 to 700 °C

  10. Effect of Firing Temperature on Humidity Sensing Properties of SnO2 Thick Film Resistor

    Directory of Open Access Journals (Sweden)

    R. Y. Borse

    2009-12-01

    Full Text Available Thick films of SnO2 were prepared using standard screen printing technique. The films were dried and fired at different temperatures. Tin-oxide is an n-type wide band gap semiconductor, whose resistance is described as a function of relative humidity. An increasing firing temperature on SnO2 film increases the sensitivity to humidity. The parameters such as sensitivity, response times and hysteresis of the SnO2 film sensors have been evaluated. The thick films were characterized by XRD, SEM and EDAX and grain size, composition of elements, relative phases are obtained.

  11. Influence of Rare Earth Doping on the Structural and Catalytic Properties of Nanostructured Tin Oxide

    Directory of Open Access Journals (Sweden)

    Maciel Adeilton

    2008-01-01

    Full Text Available AbstractNanoparticles of tin oxide, doped with Ce and Y, were prepared using the polymeric precursor method. The structural variations of the tin oxide nanoparticles were characterized by means of nitrogen physisorption, carbon dioxide chemisorption, X-ray diffraction, and X-ray photoelectron spectroscopy. The synthesized samples, undoped and doped with the rare earths, were used to promote the ethanol steam reforming reaction. The SnO2-based nanoparticles were shown to be active catalysts for the ethanol steam reforming. The surface properties, such as surface area, basicity/base strength distribution, and catalytic activity/selectivity, were influenced by the rare earth doping of SnO2and also by the annealing temperatures. Doping led to chemical and micro-structural variations at the surface of the SnO2particles. Changes in the catalytic properties of the samples, such as selectivity toward ethylene, may be ascribed to different dopings and annealing temperatures.

  12. Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation

    International Nuclear Information System (INIS)

    Al-Hamdi, Abdullah M.; Sillanpää, Mika; Dutta, Joydeep

    2015-01-01

    Highlights: • A sol–gel method used to synthesize tin oxide nanoparticles. • Nanoparticles of tin oxide doped with different iodine concentrations. • Degradation studies carried up with UV–vis, TOC, HPLC and GC instruments. • 1% iodine doped tin dioxide showed maximum photodegradation efficiency. - Abstract: Iodine doped tin oxide (SnO 2 :I) nanoparticles were prepared by sol–gel synthesis and their photocatalytic activities with phenol as a test contaminant were studied. In the presence of the catalysts, phenol degradation under direct sunlight was comparable to what was achieved under laboratory conditions. Photocatalytic oxidation reactions were studied by varying the catalyst loading, light intensity, illumination time, pH of the reactant and phenol concentration. Upon UV irradiation in the presence of SnO 2 :I nanoparticles, phenol degrades very rapidly within 30 min, forming carboxylic acid which turns the solution acidic. Phenol degradation rate with 1% iodine doped SnO 2 nanoparticles is at least an order of magnitude higher compared to the degradation achieved through undoped SnO 2 nanoparticles under similar illumination conditions

  13. Efficient photocatalytic degradation of phenol in aqueous solution by SnO2:Sb nanoparticles

    International Nuclear Information System (INIS)

    Al-Hamdi, Abdullah M.; Sillanpää, Mika; Bora, Tanujjal; Dutta, Joydeep

    2016-01-01

    Highlights: • Sb doped SnO 2 nanoparticles were synthesized using sol–gel process. • Photocatalytic degradation of phenol were studies using SnO 2 :Sb nanoparticles. • Under solar light phenol was degraded within 2 h. • Phenol mineralization and intermediates were investigated by using HPLC. - Abstract: Photodegradation of phenol in the presence of tin dioxide (SnO 2 ) nanoparticles under UV light irradiation is known to be an effective photocatalytic process. However, phenol degradation under solar light is less effective due to the large band gap of SnO 2 . In this study antimony (Sb) doped tin dioxide (SnO 2 ) nanoparticles were prepared at a low temperature (80 °C) by a sol–gel method and studied for its photocatalytic activity with phenol as a test contaminant. The catalytic degradation of phenol in aqueous media was studied using high performance liquid chromatography and total organic carbon measurements. The change in the concentration of phenol affects the pH of the solution due to the by-products formed during the photo-oxidation of phenol. The photoactivity of SnO 2 :Sb was found to be a maximum for 0.6 wt.% Sb doped SnO 2 nanoparticles with 10 mg L −1 phenol in water. Within 2 h of photodegradation, more than 95% of phenol could be removed under solar light irradiation.

  14. Effects of Textural Properties on the Response of a SnO2-Based Gas Sensor for the Detection of Chemical Warfare Agents

    Directory of Open Access Journals (Sweden)

    Duk Dong Lee

    2011-07-01

    Full Text Available The sensing behavior of SnO2-based thick film gas sensors in a flow system in the presence of a very low concentration (ppb level of chemical agent simulants such as acetonitrile, dipropylene glycol methyl ether (DPGME, dimethyl methylphosphonate (DMMP, and dichloromethane (DCM was investigated. Commercial SnO2 [SnO2(C] and nano-SnO2 prepared by the precipitation method [SnO2(P] were used to prepare the SnO2 sensor in this study. In the case of DCM and acetonitrile, the SnO2(P sensor showed higher sensor response as compared with the SnO2(C sensors. In the case of DMMP and DPGME, however, the SnO2(C sensor showed higher responses than those of the SnO2(P sensors. In particular, the response of the SnO2(P sensor increased as the calcination temperature increased from 400 °C to 800 °C. These results can be explained by the fact that the response of the SnO2-based gas sensor depends on the textural properties of tin oxide and the molecular size of the chemical agent simulant in the detection of the simulant gases (0.1–0.5 ppm.

  15. Synthesize of Graphene-Tin Oxide Nanocomposite and Its Photocatalytic Properties for the Degradation of Organic Pollutants Under Visible Light.

    Science.gov (United States)

    Shanmugam, M; Jayavel, R

    2015-09-01

    Graphene-tinoxide nanocomposite has been synthesised by coating SnO2 nanoparticles on graphene sheets by the redox reaction between graphene oxide (GO) and tin chloride. Graphene oxide was reduced to graphene and Sn2+ was oxidized to SnO2 during the redox reaction, resulting in the uniform distribution of SnO2 nanoparticles on graphene sheets. The synthesised material was characterized by XRD, SEM, AFM, FT-IR, UV-vis, TGA and Raman spectroscopic studies. SEM and AFM studies reveal the formation of wrinkled paper like structure of graphene sheets with uniform coating of SnO2 nanoparticles on either side. The strong photocatalytic degradation of Methylene orange (MO) dye was analysed using G-SnO2 nanocomposite under the visible light irradiation.

  16. Field emission from patterned SnO2 nanostructures

    International Nuclear Information System (INIS)

    Zhang Yongsheng; Yu Ke; Li Guodong; Peng Deyan; Zhang Qiuxiang; Hu Hongmei; Xu Feng; Bai Wei; Ouyang Shixi; Zhu Ziqiang

    2006-01-01

    A simple and reliable method has been developed for synthesizing finely patterned tin dioxide (SnO 2 ) nanostructure arrays on silicon substrates. A patterned Au catalyst film was prepared on the silicon wafer by radio frequency (RF) magnetron sputtering and photolithographic patterning processes. The patterned SnO 2 nanostructures arrays, a unit area is of ∼500 μm x 200 μm, were synthesized via vapor phase transport method. The surface morphology and composition of the as-synthesized SnO 2 nanostructures were characterized by means of scanning electron microscopy (SEM) and X-ray diffraction (XRD). The mechanism of formation of SnO 2 nanostructures was also discussed. The measurement of field emission (FE) revealed that the as-synthesized SnO 2 nanorods, nanowires and nanoparticles arrays have a lower turn-on field of 2.6, 3.2 and 3.9 V/μm, respectively, at the current density of 0.1 μA/cm 2 . This approach must have a wide variety of applications such as fabrications of micro-optical components and micropatterned oxide thin films used in FE-based flat panel displays, sensor arrays and so on

  17. Synthesis of SnO2 pillared carbon using long chain alkylamine grafted graphene oxide: an efficient anode material for lithium ion batteries.

    Science.gov (United States)

    Reddy, M Jeevan Kumar; Ryu, Sung Hun; Shanmugharaj, A M

    2016-01-07

    With the objective of developing new advanced composite materials that can be used as anodes for lithium ion batteries (LIBs), herein we describe the synthesis of SnO2 pillared carbon using various alkylamine (hexylamine; dodecylamine and octadecylamine) grafted graphene oxides and butyl trichlorotin precursors followed by its calcination at 500 °C for 2 h. While the grafted alkylamine induces crystalline growth of SnO2 pillars, thermal annealing of alkylamine grafted graphene oxide results in the formation of amorphous carbon coated graphene. Field emission scanning electron microscopy (FE-SEM) results reveal the successful formation of SnO2 pillared carbon on the graphene surface. X-ray diffraction (XRD), transmission electron microscopy (TEM) and Raman spectroscopy characterization corroborates the formation of rutile SnO2 crystals on the graphene surface. A significant rise in the BET surface area is observed for SnO2 pillared carbon, when compared to pristine GO. Electrochemical characterization studies of SnO2 pillared carbon based anode materials showed an enhanced lithium storage capacity and fine cyclic performance in comparison with pristine GO. The initial specific capacities of SnO2 pillared carbon are observed to be 1379 mA h g(-1), 1255 mA h g(-1) and 1360 mA h g(-1) that decrease to 750 mA h g(-1), 643 mA h g(-1) and 560 mA h g(-1) depending upon the chain length of grafted alkylamine on the graphene surface respectively. Electrochemical impedance spectral analysis reveals that the exchange current density of SnO2 pillared carbon based electrodes is higher, corroborating its enhanced electrochemical activity in comparison with GO based electrodes.

  18. Novel synthesis of tin oxide/graphene aerogel nanocomposites as anode materials for lithium ion batteries

    International Nuclear Information System (INIS)

    Wu, Zheyu; Li, Xifei; Tai, Limin; Song, Haoze; Zhang, Yiyan; Yan, Bo; Fan, Linlin; Shan, Hui; Li, Dejun

    2015-01-01

    A novel method of mechanical exfoliation followed by hydrothermal approach was proposed to synthesize the tin oxide/graphene aerogels (SnO 2 /GAs) nanocomposites. Homogeneous distribution of SnO 2 nanocrystals on GAs was confirmed by SEM, XRD and TEM characterization. It was found that optimized exfoliation of the SnS 2 is the key factor to obtain high electrochemical lithiation/delithiation performance of the anodes. The as-prepared SnO 2 /GA nanocomposites exhibited high reversible capacity (up to 1086.7 mAh g −1 after 100 cycles) and excellent cycling stability. The improved rate capability was also obtained, for instance, the reversible capacity at a current density of 800 mA g −1 is over 447.9 mAh g −1 , and then recovered to as high as 784.4 mAh g −1 at a current density of 100 mA g −1 . - Highlights: • A novel approach was employed to synthesize the SnO 2 /GA nanocomposites. • The designed SnO 2 /GAs exhibited high reversible capacity and excellent cycling stability. • The volume change challenge of SnO 2 was markedly alleviated by the GA matrix. • The novel synthesis method can be extended for other materials in lithium ion batteries

  19. Sensitivity, selectivity and stability of tin oxide nanostructures on large area arrays of microhotplates

    Science.gov (United States)

    Panchapakesan, Balaji; Cavicchi, Richard; Semancik, Steve; DeVoe, Don L.

    2006-01-01

    In this paper, the sensitivity, stability and selectivity of nanoparticle engineered tin oxide (SnO2) are reported, for microhotplate chemical sensing applications. 16 Å of metals such as nickel, cobalt, iron, copper and silver were selectively evaporated onto each column of the microhotplate array. Following evaporation, the microhotplates were heated to 500 °C and SnO2 was deposited on top of the microhotplates using a self-aligned chemical vapour deposition process. Scanning electron microscopy characterization revealed control of SnO2 nanostructures in the range of 20-121 nm. Gas sensing in seven different hydrocarbons revealed that metal nanoparticles that helped in producing faster nucleation of SnO2 resulted in smaller grain size and higher sensitivity. Sensitivity as a function of concentration and grain size is addressed for tin oxide nanostructures. Smaller grain sizes resulted in higher sensitivity of tin oxide nanostructures. Temperature programmed sensing of the devices yielded shape differences in the response between air and methanol, illustrating selectivity. Spiderweb plots were used to monitor the materials programmed selectivity. The shape differences between different gases in spiderweb plots illustrate materials selectivity as a powerful mapping approach for monitoring selectivity in various gases. Continuous monitoring in 80 ppm methanol yielded stable sensor response for more than 200 h. This comprehensive study illustrates the use of a nanoparticle engineering approach for sensitive, selective and stable gas sensing applications.

  20. Ethylene Gas Sensing Properties of Tin Oxide Nanowires Synthesized via CVD Method

    Science.gov (United States)

    Akhir, Maisara A. M.; Mohamed, Khairudin; Rezan, Sheikh A.; Arafat, M. M.; Haseeb, A. S. M. A.; Uda, M. N. A.; Nuradibah, M. A.

    2018-03-01

    This paper studies ethylene gas sensing performance of tin oxide (SnO2) nanowires (NWs) as sensing material synthesized using chemical vapor deposition (CVD) technique. The effect of NWs diameter on ethylene gas sensing characteristics were investigated. SnO2 NWs with diameter of ∼40 and ∼240 nm were deposited onto the alumina substrate with printed gold electrodes and tested for sensing characteristic toward ethylene gas. From the finding, the smallest diameter of NWs (42 nm) exhibit fast response and recovery time and higher sensitivity compared to largest diameter of NWs (∼240 nm). Both sensor show good reversibility features for ethylene gas sensor.

  1. Preparation and characterization of indium tin oxide thin films for their application as gas sensors

    International Nuclear Information System (INIS)

    Vaishnav, V.S.; Patel, P.D.; Patel, N.G.

    2005-01-01

    The structural and electrical properties of indium tin oxide (In 2 O 3 /SnO 2 ) thin films grown using direct evaporation technique on various substrates at different temperatures were studied. The effect of annealing, of films with different weight percent concentration of SnO 2 in In 2 O 3 and of different thickness on the structural and electrical properties were studied and optimized for use as gas sensor. The stability of the films against time and temperature variations was studied. The effect of the catalytic layers on the sensor microstructure and its performance towards the gas sensing application was observed

  2. SnO(2) quantum dots-reduced graphene oxide composite for enzyme-free ultrasensitive electrochemical detection of urea.

    Science.gov (United States)

    Dutta, Dipa; Chandra, Sudeshna; Swain, Akshaya K; Bahadur, Dhirendra

    2014-06-17

    Most of the urea sensors are biosensors and utilize urease, which limit their use in harsh environments. Recently, because of their exceptional ability to endorse faster electron transfer, carbonaceous material composites and quantum dots are being used for fabrication of a sensitive transducer surface for urea biosensors. We demonstrate an enzyme free ultrasensitive urea sensor fabricated using a SnO2 quantum dots (QDs)/reduced graphene oxide (RGO) composite. Due to the synergistic effect of the constituents, the SnO2 QDs/RGO (SRGO) composite proved to be an excellent probe for electrochemical sensing. The morphology and structure of the composite was characterized by various techniques, and it was observed that SnO2 QDs are decorated on RGO layers. Electrochemical studies were performed to evaluate the characteristics of the sensor toward detection of urea. Amperometry studies show that the SRGO/GCE electrode is sensitive to urea in the concentration range of 1.6 × 10(-14)-3.9 × 10(-12) M, with a detection limit of as low as 11.7 fM. However, this is an indirect measurement for urea wherein the analytical signal is recorded as a decrease in the amperommetric and/or voltammetric current from the solution redox species ferrocyanide. The porous structure of the SRGO matrix offers a very low transport barrier and thus promotes rapid diffusion of the ionic species from the solution to the electrode, leading to a rapid response time (∼5 s) and ultrahigh sensitivity (1.38 μA/fM). Good analytical performance in the presence of interfering agents, low cost, and easy synthesis methodology suggest that SRGO can be quite promising as an electroactive material for effective urea sensing.

  3. Effect of Growth Parameters on SnO2 Nanowires Growth by Electron Beam Evaporation Method

    Science.gov (United States)

    Rakesh Kumar, R.; Manjula, Y.; Narasimha Rao, K.

    2018-02-01

    Tin oxide (SnO2) nanowires were synthesized via catalyst assisted VLS growth mechanism by the electron beam evaporation method at a growth temperature of 450 °C. The effects of growth parameters such as evaporation rate of Tin, catalyst film thickness, and different types of substrates on the growth of SnO2 nanowires were studied. Nanowires (NWs) growth was completely seized at higher tin evaporation rates due to the inability of the catalyst particle to initiate the NWs growth. Nanowires diameters were able to tune with catalyst film thickness. Nanowires growth was completely absent at higher catalyst film thickness due to agglomeration of the catalyst film. Optimum growth parameters for SnO2 NWs were presented. Nanocomposites such as Zinc oxide - SnO2, Graphene oxide sheets- SnO2 and Graphene nanosheets-SnO2 were able to synthesize at a lower substrate temperature of 450 °C. These nanocompsoites will be useful in enhancing the capacity of Li-ion batteries, the gas sensing response and also useful in increasing the photo catalytic activity.

  4. Ab initio study of thermoelectric properties of doped SnO_2 superlattices

    International Nuclear Information System (INIS)

    Borges, P.D.; Silva, D.E.S.; Castro, N.S.; Ferreira, C.R.; Pinto, F.G.; Tronto, J.; Scolfaro, L.

    2015-01-01

    Transparent conductive oxides, such as tin dioxide (SnO_2), have recently shown to be promising materials for thermoelectric applications. In this work we studied the thermoelectric properties of Fe-, Sb- and Zn-uniformly doping and co-doping SnO_2, as well as of Sb and Zn planar (or delta)-doped layers in SnO_2 forming oxide superlattices (SLs). Based on the semiclassical Boltzmann transport equations (BTE) in conjunction with ab initio electronic structure calculations, the Seebeck coefficient (S) and figure of merit (ZT) are obtained for these systems, and are compared with available experimental data. The delta doping approach introduces a remarkable modification in the electronic structure of tin dioxide, when compared with the uniform doping, and colossal values for ZT are predicted for the delta-doped oxide SLs. This result is a consequence of the two-dimensional electronic confinement and the strong anisotropy introduced by the doped planes. In comparison with the uniformly doped systems, our predictions reveal a promising use of delta-doped SnO_2 SLs for enhanced S and ZT, which emerge as potential candidates for thermoelectric applications. - Graphical abstract: Band structure and Figure of merit for SnO2:Sb superlattice along Z direction, P. D. Borges, D. E. S. Silva, N. S. Castro, C. R. Ferreira, F. G. Pinto, J. Tronto and L. Scolfaro, Ab initio study of thermoelectric properties of doped SnO2 superlattices. - Highlights: • Thermoelectric properties of SnO_2-based alloys and superlattices. • High figure of merit is predicted for planar-doped SnO_2 superlattices. • Nanotechnology has an important role for the development of thermoelectric devices.

  5. Nanostructured tin oxide films: Physical synthesis, characterization, and gas sensing properties.

    Science.gov (United States)

    Ingole, S M; Navale, S T; Navale, Y H; Bandgar, D K; Stadler, F J; Mane, R S; Ramgir, N S; Gupta, S K; Aswal, D K; Patil, V B

    2017-05-01

    Nanostructured tin oxide (SnO 2 ) films are synthesized using physical method i.e. thermal evaporation and are further characterized with X-ray diffraction, X-ray photoelectron spectroscopy, scanning electron microscopy, transmission electron microscopy, and atomic force microscopy measurement techniques for confirming its structure and morphology. The chemiresistive properties of SnO 2 films are studied towards different oxidizing and reducing gases where these films have demonstrated considerable selectivity towards oxidizing nitrogen dioxide (NO 2 ) gas with a maximum response of 403% to 100ppm @200°C, and fast response and recovery times of 4s and 210s, respectively, than other test gases. In addition, SnO 2 films are enabling to detect as low as 1ppm NO 2 gas concentration @200°C with 23% response enhancement. Chemiresistive performances of SnO 2 films are carried out in the range of 1-100ppm and reported. Finally, plausible adsorption and desorption reaction mechanism of NO 2 gas molecules with SnO 2 film surface has been thoroughly discussed by means of an impedance spectroscopy analysis. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Nonlinear I–V characteristics study of doped SnO2

    Indian Academy of Sciences (India)

    Unknown

    type semiconductor with many interesting electronic pro- perties. Tin oxide ... The current–voltage curves were plotted on log–log scale from which the ... 4. Conclusion. A new varistor system based on doped SnO2 system is prepared and it ...

  7. Anchoring ultrafine Pd nanoparticles and SnO2 nanoparticles on reduced graphene oxide for high-performance room temperature NO2 sensing.

    Science.gov (United States)

    Wang, Ziying; Zhang, Tong; Zhao, Chen; Han, Tianyi; Fei, Teng; Liu, Sen; Lu, Geyu

    2018-03-15

    In this paper, we demonstrate room-temperature NO 2 gas sensors using Pd nanoparticles (NPs) and SnO 2 NPs decorated reduced graphene oxide (Pd-SnO 2 -RGO) hybrids as sensing materials. It is found that ultrafine Pd NPs and SnO 2 NPs with particle sizes of 3-5 nm are attached to RGO nanosheets. Compared to SnO 2 -RGO hybrids, the sensor based on Pd-SnO 2 -RGO hybrids exhibited higher sensitivity at room temperature, where the response to 1 ppm NO 2 was 3.92 with the response time and recovery time being 13 s and 105 s. Moreover, such sensor exhibited excellent selectivity, and low detection limit (50 ppb). In addition to high transport capability of RGO as well as excellent NO 2 adsorption ability derived from ultrafine SnO 2 NPs and Pd NPs, the superior sensing performances of the hybrids were attributed to the synergetic effect of Pd NPs, SnO 2 NPs and RGO. Particularly, the excellent sensing performances were related to high conductivity and catalytic activity of Pd NPs. Finally, the sensing mechanism for NO 2 sensing and the reason for enhanced sensing performances by introduction of Pd NPs are also discussed. Copyright © 2017 Elsevier Inc. All rights reserved.

  8. Ultra-fine SnO2 nanoparticles doubly embedded in amorphous carbon and reduced graphene oxide (rGO) for superior lithium storage

    International Nuclear Information System (INIS)

    Sher Shah, Md. Selim Arif; Lee, Jooyoung; Park, A. Reum; Choi, Youngjin; Kim, Woo-Jae; Park, Juhyun; Chung, Chan-Hwa; Kim, Jaeyun; Lim, Byungkwon; Yoo, Pil J.

    2017-01-01

    SnO 2 is a well-studied anode material for lithium ion batteries (LIBs). However, it undergoes severe capacity fading because of a large volume change (∼300%) during cycling. Composites of SnO 2 with electro-conductive graphene would deliver improved capacity and rate performance. Nevertheless, achieving the theoretical capacity of SnO 2 is still elusive, mainly because of disintegration of the active material from graphene and severe aggregation of SnO 2 , or Sn nanoparticles produced upon cycling. To surmount these limitations, in this work, nanocomposites containing ultra-fine sized SnO 2 nanoparticles (UFSN) with reduced graphene oxide and amorphous carbon were synthesized in a single step at low temperature and environmentally benign way, in which ascorbic acid was employed as the carbon source and reducing agent. UFSN could decrease the lithium ion diffusion path length. As a result of effective buffering effect afforded by the mesoporous structure against volume change and improved lithium ion diffusivity, the ternary nanocomposite achieves ultra-high capacity of 1245 mAh g −1 after 210 cycles at 100 mA g −1 and excellent cycling stability. Since the proposed approach is facile, straightforward, and highly reproducible, it is anticipated that this system would be a potential alternative to the conventional graphite anode for LIBs.

  9. Microwave synthesis and characterisation of tin dioxide (SnO2) coated multi-walled carbon nanotubes

    CSIR Research Space (South Africa)

    Motshekga, S

    2010-09-01

    Full Text Available an attractive material for application in solar cells, field effect transistors, catalysis and gas-sensing1-3. Nanostructured composite materials of carbon nanotubes and metal oxides promise superior performance over conventional approaches due to the ability...

  10. Surface engineering of one-dimensional tin oxide nanostructures for chemical sensors

    International Nuclear Information System (INIS)

    Ma, Yuanyuan; Qu, Yongquan; Zhou, Wei

    2013-01-01

    Nanostructured materials are promising candidates for chemical sensors due to their fascinating physicochemical properties. Among various candidates, tin oxide (SnO 2 ) has been widely explored in gas sensing elements due to its excellent chemical stability, low cost, ease of fabrication and remarkable reproducibility. We are presenting an overview on recent investigations on 1-dimensional (1D) SnO 2 nanostructures for chemical sensing. In particular, we focus on the performance of devices based on surface engineered SnO 2 nanostructures, and on aspects of morphology, size, and functionality. The synthesis and sensing mechanism of highly selective, sensitive and stable 1D nanostructures for use in chemical sensing are discussed first. This is followed by a discussion of the relationship between the surface properties of the SnO 2 layer and the sensor performance from a thermodynamic point of view. Then, the opportunities and recent progress of chemical sensors fabricated from 1D SnO 2 heterogeneous nanostructures are discussed. Finally, we summarize current challenges in terms of improving the performance of chemical (gas) sensors using such nanostructures and suggest potential applications. (author)

  11. Effects of gas flow rate on the structure and elemental composition of tin oxide thin films deposited by RF sputtering

    Science.gov (United States)

    Al-Mansoori, Muntaser; Al-Shaibani, Sahar; Al-Jaeedi, Ahlam; Lee, Jisung; Choi, Daniel; Hasoon, Falah S.

    2017-12-01

    Photovoltaic technology is one of the key answers for a better sustainable future. An important layer in the structure of common photovoltaic cells is the transparent conductive oxide. A widely applied transparent conductive oxide is tin oxide (SnO2). The advantage of using tin oxide comes from its high stability and low cost in processing. In our study, we investigate effects of working gas flow rate and oxygen content in radio frequency (RF)-sputtering system on the growth of intrinsic SnO2 (i-SnO2) layers. X-ray diffraction results showed that amorphous-like with nano-crystallite structure, and the surface roughness varied from 1.715 to 3.936 nm. X-Ray photoelectron spectroscopy analysis showed different types of point defects, such as tin interstitials and oxygen vacancies, in deposited i-SnO2 films.

  12. Effects of gas flow rate on the structure and elemental composition of tin oxide thin films deposited by RF sputtering

    Directory of Open Access Journals (Sweden)

    Muntaser Al-Mansoori

    2017-12-01

    Full Text Available Photovoltaic technology is one of the key answers for a better sustainable future. An important layer in the structure of common photovoltaic cells is the transparent conductive oxide. A widely applied transparent conductive oxide is tin oxide (SnO2. The advantage of using tin oxide comes from its high stability and low cost in processing. In our study, we investigate effects of working gas flow rate and oxygen content in radio frequency (RF-sputtering system on the growth of intrinsic SnO2 (i-SnO2 layers. X-ray diffraction results showed that amorphous-like with nano-crystallite structure, and the surface roughness varied from 1.715 to 3.936 nm. X-Ray photoelectron spectroscopy analysis showed different types of point defects, such as tin interstitials and oxygen vacancies, in deposited i-SnO2 films.

  13. Hybrid nanocomposite based on cellulose and tin oxide: growth, structure, tensile and electrical characteristics

    International Nuclear Information System (INIS)

    Mahadeva, Suresha K; Kim, Jaehwan

    2011-01-01

    A highly flexible nanocomposite was developed by coating a regenerated cellulose film with a thin layer of tin oxide (SnO 2 ) by liquid-phase deposition. Tin oxide was crystallized in solution and formed nanocrystal coatings on regenerated cellulose. The nanocrystalline layers did not exfoliate from cellulose. Transmission electron microscopy and energy dispersive x-ray spectroscopy suggest that SnO 2 was not only deposited over the cellulose surface, but also nucleated and grew inside the cellulose film. Current-voltage characteristics of the nanocomposite revealed that its electrical resistivity decreases with deposition time, with the lowest value obtained for 24 h of deposition. The cellulose-SnO 2 hybrid nanocomposite can be used for biodegradable and disposable chemical, humidity and biosensors.

  14. Shape Engineering Driven by Selective Growth of SnO2 on Doped Ga2O3 Nanowires.

    Science.gov (United States)

    Alonso-Orts, Manuel; Sánchez, Ana M; Hindmarsh, Steven A; López, Iñaki; Nogales, Emilio; Piqueras, Javier; Méndez, Bianchi

    2017-01-11

    Tailoring the shape of complex nanostructures requires control of the growth process. In this work, we report on the selective growth of nanostructured tin oxide on gallium oxide nanowires leading to the formation of SnO 2 /Ga 2 O 3 complex nanostructures. Ga 2 O 3 nanowires decorated with either crossing SnO 2 nanowires or SnO 2 particles have been obtained in a single step treatment by thermal evaporation. The reason for this dual behavior is related to the growth direction of trunk Ga 2 O 3 nanowires. Ga 2 O 3 nanowires grown along the [001] direction favor the formation of crossing SnO 2 nanowires. Alternatively, SnO 2 forms rhombohedral particles on [110] Ga 2 O 3 nanowires leading to skewer-like structures. These complex oxide structures were grown by a catalyst-free vapor-solid process. When pure Ga and tin oxide were used as source materials and compacted powders of Ga 2 O 3 acted as substrates, [110] Ga 2 O 3 nanowires grow preferentially. High-resolution transmission electron microscopy analysis reveals epitaxial relationship lattice matching between the Ga 2 O 3 axis and SnO 2 particles, forming skewer-like structures. The addition of chromium oxide to the source materials modifies the growth direction of the trunk Ga 2 O 3 nanowires, growing along the [001], with crossing SnO 2 wires. The SnO 2 /Ga 2 O 3 junctions does not meet the lattice matching condition, forming a grain boundary. The electronic and optical properties have been studied by XPS and CL with high spatial resolution, enabling us to get both local chemical and electronic information on the surface in both type of structures. The results will allow tuning optical and electronic properties of oxide complex nanostructures locally as a function of the orientation. In particular, we report a dependence of the visible CL emission of SnO 2 on its particular shape. Orange emission dominates in SnO 2 /Ga 2 O 3 crossing wires while green-blue emission is observed in SnO 2 particles attached to Ga 2

  15. Fabrication of SnO2-Reduced Graphite Oxide Monolayer-Ordered Porous Film Gas Sensor with Tunable Sensitivity through Ultra-Violet Light Irradiation

    Science.gov (United States)

    Xu, Shipu; Sun, Fengqiang; Yang, Shumin; Pan, Zizhao; Long, Jinfeng; Gu, Fenglong

    2015-01-01

    A new graphene-based composite structure, monolayer-ordered macroporous film composed of a layer of orderly arranged macropores, was reported. As an example, SnO2-reduced graphite oxide monolayer-ordered macroporous film was fabricated on a ceramic tube substrate under the irradiation of ultra-violet light (UV), by taking the latex microsphere two-dimensional colloid crystal as a template. Graphite oxide sheets dispersed in SnSO4 aqueous solution exhibited excellent affinity with template microspheres and were in situ incorporated into the pore walls during UV-induced growth of SnO2. The growing and the as-formed SnO2, just like other photocatalytic semiconductor, could be excited to produce electrons and holes under UV irradiation. Electrons reduced GO and holes adsorbed corresponding negative ions, which changed the properties of the composite film. This film was directly used as gas-sensor and was able to display high sensitivity in detecting ethanol gas. More interestingly, on the basis of SnO2-induced photochemical behaviours, this sensor demonstrated tunable sensitivity when UV irradiation time was controlled during the fabrication process and post in water, respectively. This study provides efficient ways of conducting the in situ fabrication of a semiconductor-reduced graphite oxide film device with uniform surface structure and controllable properties. PMID:25758292

  16. UV-visible spectroscopic estimation of photodegradation of rhodamine-B dye using tin(IV) oxide nanoparticles.

    Science.gov (United States)

    Sangami, G; Dharmaraj, N

    2012-11-01

    Nanocrystalline, tin(IV) oxide (SnO(2)) particles has been prepared by thermal decomposition of tin oxalate precursor obtained from the reactions of tin(IV) chloride and sodium oxalate using eggshell membrane (ESM). The as-prepared SnO(2) nanoparticles were characterized by thermal studies, transmission electron microscopy (TEM), powder X-ray diffraction (XRD), Raman, FT-IR and UV-visible studies and used as a photocatalyst for the degradation of rhodamine-B (Rh-B) dye. The size of the prepared nanoparticles was in the range of 5-12nm as identified from the TEM images. Powder XRD data revealed the presence of a tetragonal, rutile crystalline phase of the tin(IV) oxide nanoparticles. Thermal analysis showed that the decomposition of tin oxalate precursor to yield the titled tin(IV) oxide nanoparticles was completed below 500°C. The extent of degradation of Rh-B in the presence of SnO(2) monitored by absorption spectral measurements demonstrated that 94.48% of the selected dye was degraded upon irradiation with UV light for 60 min. Copyright © 2012 Elsevier B.V. All rights reserved.

  17. Synthesis of tin oxide nanoparticle film by cathodic electrodeposition.

    Science.gov (United States)

    Kim, Seok; Lee, Hochun; Park, Chang Min; Jung, Yongju

    2012-02-01

    Three-dimensional SnO2 nanoparticle films were deposited onto a copper substrate by cathodic electrodeposition in a nitric acid solution. A new formation mechanism for SnO2 films is proposed based on the oxidation of Sn2+ ion to Sn4+ ion by NO+ ion and the hydrolysis of Sn4+. The particle size of SnO2 was controlled by deposition potential. The SnO2 showed excellent charge capacity (729 mAh/g) at a 0.2 C rate and high rate capability (460 mAh/g) at a 5 C rate.

  18. Extraordinary improvement of gas-sensing performances in SnO2 nanofibers due to creation of local p-n heterojunctions by loading reduced graphene oxide nanosheets.

    Science.gov (United States)

    Lee, Jae-Hyoung; Katoch, Akash; Choi, Sun-Woo; Kim, Jae-Hun; Kim, Hyoun Woo; Kim, Sang Sub

    2015-02-11

    We propose a novel approach to improve the gas-sensing properties of n-type nanofibers (NFs) that involves creation of local p-n heterojunctions with p-type reduced graphene oxide (RGO) nanosheets (NSs). This work investigates the sensing behaviors of n-SnO2 NFs loaded with p-RGO NSs as a model system. n-SnO2 NFs demonstrated greatly improved gas-sensing performances when loaded with an optimized amount of p-RGO NSs. Loading an optimized amount of RGOs resulted in a 20-fold higher sensor response than that of pristine SnO2 NFs. The sensing mechanism of monolithic SnO2 NFs is based on the joint effects of modulation of the potential barrier at nanograin boundaries and radial modulation of the electron-depletion layer. In addition to the sensing mechanisms described above, enhanced sensing was obtained for p-RGO NS-loaded SnO2 NFs due to creation of local p-n heterojunctions, which not only provided a potential barrier, but also functioned as a local electron absorption reservoir. These mechanisms markedly increased the resistance of SnO2 NFs, and were the origin of intensified resistance modulation during interaction of analyte gases with preadsorbed oxygen species or with the surfaces and grain boundaries of NFs. The approach used in this work can be used to fabricate sensitive gas sensors based on n-type NFs.

  19. Characterization of Reduced Graphene Oxide (rGO-Loaded SnO2 Nanocomposite and Applications in C2H2 Gas Detection

    Directory of Open Access Journals (Sweden)

    Lingfeng Jin

    2016-12-01

    Full Text Available Acetylene (C2H2 gas sensors were developed by synthesizing a reduced graphene oxide (rGO-loaded SnO2 hybrid nanocomposite via a facile two-step hydrothermal method. Morphological characterizations showed the formation of well-dispersed SnO2 nanoparticles loaded on the rGO sheets with excellent transparency and obvious fold boundary. Structural analysis revealed good agreement with the standard crystalline phases of SnO2 and rGO. Gas sensing characteristics of the synthesized materials were carried out in a temperature range of 100–300 °C with various concentrations of C2H2 gas. At 180 °C, the SnO2–rGO hybrid showed preferable detection of C2H2 with high sensor response (12.4 toward 50 ppm, fast response-recovery time (54 s and 23 s, limit of detection (LOD of 1.3 ppm and good linearity, with good selectivity and long-term stability. Furthermore, the possible gas sensing mechanism of the SnO2–rGO nanocomposites for C2H2 gas were summarized and discussed in detail. Our work indicates that the addition of rGO would be effective in enhancing the sensing properties of metal oxide-based gas sensors for C2H2 and may make a contribution to the development of an excellent ppm-level gas sensor for on-line monitoring of dissolved C2H2 gas in transformer oil.

  20. Electrical and optical properties of nitrogen doped SnO2 thin films deposited on flexible substrates by magnetron sputtering

    International Nuclear Information System (INIS)

    Fang, Feng; Zhang, Yeyu; Wu, Xiaoqin; Shao, Qiyue; Xie, Zonghan

    2015-01-01

    Graphical abstract: The best SnO 2 :N TCO film: about 80% transmittance and 9.1 × 10 −4 Ω cm. - Highlights: • Nitrogen-doped tin oxide film was deposited on PET by RF-magnetron sputtering. • Effects of oxygen partial pressure on the properties of thin films were investigated. • For SnO 2 :N film, visible light transmittance was 80% and electrical resistivity was 9.1 × 10 −4 Ω cm. - Abstract: Nitrogen-doped tin oxide (SnO 2 :N) thin films were deposited on flexible polyethylene terephthalate (PET) substrates at room temperature by RF-magnetron sputtering. Effects of oxygen partial pressure (0–4%) on electrical and optical properties of thin films were investigated. Experimental results showed that SnO 2 :N films were amorphous state, and O/Sn ratios of SnO 2 :N films were deviated from the standard stoichiometry 2:1. Optical band gap of SnO 2 :N films increased from approximately 3.10 eV to 3.42 eV as oxygen partial pressure increased from 0% to 4%. For SnO 2 :N thin films deposited on PET, transmittance was about 80% in the visible light region. The best transparent conductive oxide (TCO) deposited on flexible PET substrates was SnO 2 :N thin films preparing at 2% oxygen partial pressure, the transmittance was about 80% and electrical conductivity was about 9.1 × 10 −4 Ω cm

  1. F-doped SnO2 thin films grown on flexible substrates at low temperatures by pulsed laser deposition

    International Nuclear Information System (INIS)

    Kim, H.; Auyeung, R.C.Y.; Pique, A.

    2011-01-01

    Fluorine-doped tin oxide (SnO 2 :F) films were deposited on polyethersulfone plastic substrates by pulsed laser deposition. The electrical and optical properties of the SnO 2 :F films were investigated as a function of deposition conditions such as substrate temperature and oxygen partial pressure during deposition. High quality SnO 2 :F films were achieved under an optimum oxygen pressure range (7.4-8 Pa) at relatively low growth temperatures (25-150 deg. C). As-deposited films exhibited low electrical resistivities of 1-7 mΩ-cm, high optical transmittance of 80-90% in the visible range, and optical band-gap energies of 3.87-3.96 eV. Atomic force microscopy measurements revealed a reduced root mean square surface roughness of the SnO 2 :F films compared to that of the bare substrates indicating planarization of the underlying substrate.

  2. Facile Fabrication of MoS2-Modified SnO2 Hybrid Nanocomposite for Ultrasensitive Humidity Sensing.

    Science.gov (United States)

    Zhang, Dongzhi; Sun, Yan'e; Li, Peng; Zhang, Yong

    2016-06-08

    An ultrasensitive humidity sensor based on molybdenum-disulfide- (MoS2)-modified tin oxide (SnO2) nanocomposite has been demonstrated in this work. The nanostructural, morphological, and compositional properties of an as-prepared MoS2/SnO2 nanocomposite were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD), energy dispersive spectrometry (EDS), nitrogen sorption analysis, and Raman spectroscopy, which confirmed its successful preparation and rationality. The sensing characteristics of the MoS2/SnO2 hybrid film device against relative humidity (RH) were investigated at room temperature. The RH sensing results revealed an unprecedented response, ultrafast response/recovery behaviors, and outstanding repeatability. To our knowledge, the sensor response yielded in this work was tens of times higher than that of the existing humidity sensors. Moreover, the MoS2/SnO2 hybrid nanocomposite film sensor exhibited great enhancement in humidity sensing performances as compared to the pure MoS2, SnO2, and graphene counterparts. Furthermore, complex impedance spectroscopy and bode plots were employed to understand the underlying sensing mechanisms of the MoS2/SnO2 nanocomposite toward humidity. The synthesized MoS2/SnO2 hybrid composite was proved to be an excellent candidate for constructing ultrahigh-performance humidity sensor toward various applications.

  3. Tin-antimony oxide oxidation catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Berry, Frank J. [Open University, Department of Chemistry (United Kingdom)

    1998-12-15

    Tin-antimony oxide catalysts for the selective oxidation of hydrocarbons have been made by precipitation techniques. The dehydration of the amorphous dried precipitate by calcination at increasingly higher temperatures induces the crystallisation of a rutile-related tin dioxide-type phase and the segregation of antimony oxides which volatilise at elevated temperatures. The rutile-related tin dioxide-type phase contains antimony(V) in the bulk and antimony(III) in the surface. Specific catalytic activity for the oxidative dehydrogenation of butene to butadiene is associated with materials with large concentrations of antimony(III) in the surface.

  4. SnO2 promoted by alkali metal oxides for soot combustion: The effects of surface oxygen mobility and abundance on the activity

    Science.gov (United States)

    Rao, Cheng; Shen, Jiating; Wang, Fumin; Peng, Honggen; Xu, Xianglan; Zhan, Hangping; Fang, Xiuzhong; Liu, Jianjun; Liu, Wenming; Wang, Xiang

    2018-03-01

    In this study, SnO2-based catalysts promoted by different alkali metal oxides with a Sn/M (M = Li, Na, K, Cs) molar ratio of 9/1 have been prepared for soot combustion. In comparison with the un-modified SnO2 support, the activity of the modified catalysts has been evidently enhanced, following the sequence of CsSn1-9 > KSn1-9 > NaSn1-9 > LiSn1-9 > SnO2. As testified by Raman, H2-TPR, soot-TPR-MS, XPS and O2-TPD results, the incorporation of various alkali metal oxides can induce the formation of more abundant and mobile oxygen species on the surface of the catalysts. Moreover, quantified results have proved that the amount of the surface active oxygen species is nearly proportional to the activity of the catalysts. CsSn1-9, the catalyst promoted by cesium oxide, owns the largest amount of surface mobile oxygen species, thus having the highest activity among all the studied catalysts. It is concluded that the amount of surface active and mobile oxygen species is the major factor determining the activity of the catalysts for soot combustion.

  5. Efecto de la naturaleza del precursor sobre las caracteristicas de las nanoparticulas de SnO2 sintetizadas Effect of the precursor's nature on characteristics of synthesized SnO2 nanoparticles

    Directory of Open Access Journals (Sweden)

    Carlos E. Ararat-Ibarguen

    2007-01-01

    Full Text Available Tin oxide (SnO2 is widely used in industry as raw material for electronic devices, plating of different types of materials, for dyes and pigments, for electroplating, heterogeneous catalysis, etc. In this work SnO2 was obtained by a controlled precipitation method with special attention to the effects the tin precursor has on the microstructure of the final product. The most appropriate pH for obtaining SnO2 with the rutile structure as the main phase is 6.25 for SnCl2 and 6.40 for SnSO4. After heat treatment at 600 °C, particles of nanometric order (~10 - 30 nm approx were obtained. The characterization of the solid phase was made by X-ray diffraction (XRD, thermal analysis (DTA/TG, transmission electron microscopy (TEM and Fourier transformed infrared spectroscopy (FTIR.

  6. Incorporation of graphene into SnO2 photoanodes for dye-sensitized solar cells

    Science.gov (United States)

    Batmunkh, Munkhbayar; Dadkhah, Mahnaz; Shearer, Cameron J.; Biggs, Mark J.; Shapter, Joseph G.

    2016-11-01

    In dye-sensitized solar cell (DSSC) photoanodes, tin dioxide (SnO2) structures present a promising alternative semiconducting oxide to the conventional titania (TiO2), but they suffer from poor photovoltaic (PV) efficiency caused by insufficient dye adsorption and low energy value of the conduction band. A hybrid structure consisting of SnO2 and reduced graphene oxide (SnO2-RGO) was synthesized via a microwave-assisted method and has been employed as a photoanode in DSSCs. Incorporation of RGO into the SnO2 photoanode enhanced the power conversion efficiency of DSSC device by 91.5%, as compared to the device assembled without RGO. This efficiency improvement can be attributed to increased dye loading, enhanced electron transfer and addition of suitable energy levels in the photoanode. Finally, the use of RGO addresses the major shortcoming of SnO2 when employed as a DSSC photoanode, namely poor dye adsorption and slow electron transfer rate.

  7. Graphene nanoribbon and nanostructured SnO2 composite anodes for lithium ion batteries.

    Science.gov (United States)

    Lin, Jian; Peng, Zhiwei; Xiang, Changsheng; Ruan, Gedeng; Yan, Zheng; Natelson, Douglas; Tour, James M

    2013-07-23

    A composite made from graphene nanoribbons (GNRs) and tin oxide (SnO2) nanoparticles (NPs) is synthesized and used as the anode material for lithium ion batteries (LIBs). The conductive GNRs, prepared using sodium/potassium unzipping of multiwall carbon nanotubes, can boost the lithium storage performance of SnO2 NPs. The composite, as an anode material for LIBs, exhibits reversible capacities of over 1520 and 1130 mAh/g for the first discharge and charge, respectively, which is more than the theoretical capacity of SnO2. The reversible capacity retains ~825 mAh/g at a current density of 100 mA/g with a Coulombic efficiency of 98% after 50 cycles. Further, the composite shows good power performance with a reversible capacity of ~580 mAh/g at the current density of 2 A/g. The high capacity, good power performance and retention can be attributed to uniformly distributed SnO2 NPs along the high-aspect-ratio GNRs. The GNRs act as conductive additives that buffer the volume changes of SnO2 during cycling. This work provides a starting point for exploring the composites made from GNRs and other transition metal oxides for lithium storage applications.

  8. Correlation between the structure and optical transition characteristic energies of annealed tin oxide films

    International Nuclear Information System (INIS)

    Majid, W.H.A.; Muhamad, M.R.

    1990-01-01

    Thin films of tin oxide were prepared by room temperature thermal evaporation of blue-black stannous-oxide, SnO powder synthesized from metal tin. X-ray diffractograms reveal that as prepared amorphous samples form polycrystal of SnO by annealing at 300 0 C in air ambient for 30 minutes and they will be oxidized to polycrystal of SnO 2 with further annealing at 500 0 C or above. Optical measurements indicate that the dispersion energy E d and the single oscillator strength E 0 are highest for SnO polycrystal with a magnitude for about 14.0 eV and 4.0 eV respectively compared to 10.4 eV and 3.4 eV for SnO 2 . Further, the plasma energy E p was determined to be in the range of 3.4 eV to 8 eV; increases with increasing composition of SnO 2 . The density of valence electron N(E) can be estimated from the plasma energy E p

  9. In-Situ Growth and Characterization of Indium Tin Oxide Nanocrystal Rods

    Directory of Open Access Journals (Sweden)

    Yan Shen

    2017-11-01

    Full Text Available Indium tin oxide (ITO nanocrystal rods were synthesized in-situ by a vapor-liquid-solid (VLS method and electron beam evaporation technique. When the electron-beam gun bombarded indium oxide (In2O3 and tin oxide (SnO2 mixed sources, indium and tin droplets appeared and acted as catalysts. The nanocrystal rods were in-situ grown on the basis of the metal catalyst point. The nanorods have a single crystal structure. Its structure was confirmed by X-ray diffraction (XRD and transmission electron microscopy (TEM. The surface morphology was analyzed by scanning electron microscopy (SEM. During the evaporation, a chemical process was happened and an In2O3 and SnO2 solid solution was formed. The percentage of doped tin oxide was calculated by Vegard’s law to be 3.18%, which was in agreement with the mixture ratio of the experimental data. The single crystal rod had good semiconductor switch property and its threshold voltage of single rod was approximately 2.5 V which can be used as a micro switch device. The transmission rate of crystalline nanorods ITO film was over 90% in visible band and it was up to 95% in the blue green band as a result of the oxygen vacancy recombination luminescence.

  10. Effect of oxidizer on grain size and low temperature DC electrical conductivity of tin oxide nanomaterial synthesized by gel combustion method

    International Nuclear Information System (INIS)

    Rajeeva, M. P.; Jayanna, H. S.; Ashok, R. L.; Naveen, C. S.; Bothla, V. Prasad

    2014-01-01

    Nanocrystalline Tin oxide material with different grain size was synthesized using gel combustion method by varying the fuel (C 6 H 8 O 7 ) to oxidizer (HNO 3 ) molar ratio by keeping the amount of fuel as constant. The prepared samples were characterized by using X-Ray Diffraction (XRD), Scanning Electron Microscope (SEM) and Energy Dispersive Analysis X-ray Spectroscopy (EDAX). The effect of fuel to oxidizer molar ratio in the gel combustion method was investigated by inspecting the grain size of nano SnO 2 powder. The grain size was found to be reduced with the amount of oxidizer increases from 0 to 6 moles in the step of 2. The X-ray diffraction patterns of the calcined product showed the formation of high purity tetragonal tin (IV) oxide with the grain size in the range of 12 to 31 nm which was calculated by Scherer's formula. Molar ratio and temperature dependence of DC electrical conductivity of SnO 2 nanomaterial was studied using Keithley source meter. DC electrical conductivity of SnO 2 nanomaterial increases with the temperature from 80K to 300K. From the study it was observed that the DC electrical conductivity of SnO 2 nanomaterial decreases with the grain size at constant temperature

  11. Comparative analysis of physico-chemical and gas sensing characteristics of two different forms of SnO_2 films

    International Nuclear Information System (INIS)

    Kwoka, M.; Ottaviano, L.; Szuber, J.

    2017-01-01

    Highlights: • Two different forms of SnO_2 deposited on Si substrate. • Crystallinity and surface/subsurface morphology controlled by XRD, SEM and AFM. • Surface/subsurface chemistry including stoichiometry and contaminations derived from XPS. • Comparative analysis of gas sensor characteristics of SnO_2 in NO_2 atmosphere. • Correlations between physico-chemical properties and gas sensor characteristics. - Abstract: In this paper the results of studies of comparative studies on the crystallinity, morphology and chemistry combined with the gas sensor response of two different forms of tin dioxide (SnO_2) films prepared by the Rheotaxial Growth and Thermal Oxidation (RGTO) and by the Laser-enhanced Chemical Vapour Deposition (L-CVD) methods, respectively, are presented. For this purpose the X-ray Diffraction (XRD), Scanning Electron Microscopy (SEM), Atomic Force Microscopy (AFM) and X-ray Photoelectron spectroscopy (XPS) have been used. XRD studies for both samples show the contribution from the crystalline SnO_2 in the cassiterite rutile phase without any evident contribution from the tin oxide (SnO) phase. SEM and AFM studies show that the surface morphology of RGTO and L-CVD SnO_2 samples are characterized by grains/nanograins of different size and surface roughness. In turn XPS studies confirm that for both SnO_2 samples a slight nonstoichiometry with a relative [O]/[Sn] concentration of 1.8, and slightly different amount of C contamination at the surface of internal grains with relative [C]/[Sn] concentration of 3.5 and 3.2, respectively. This undesired C contamination cannot be ignored because it creates an uncontrolled barrier for the potential gas adsorption at the internal surface of sensor material. This is confirmed by the gas sensor response in NO_2 atmosphere of both SnO_2 samples because the sensitivity is evidently smaller for RGTO SnO_2 with respect to the L-CVD SnO_2 samples, whereas the response time showed a completely opposite tendency

  12. TDPAC characterization of tin oxides using 181Ta

    International Nuclear Information System (INIS)

    Moreno, M.S.; Desimoni, J.; Requejo, F.G.; Renteria, M.; Bibiloni, A.G.

    1991-01-01

    In connection with a general study of the evolution of tin-oxygen thin films, we report here on the hyperfine interactions of 181 Ta substitutionally replacing tin in the isolated phases SnO and SnO 2 . For this purpose, pure SnO pressed powder and a thin SnO 2 film were implanted with 181 Hf. In both cases, unique quadrupole frequencies were found after thermal annealing treatments. The results indicate that the following hyperfine parameters: ν Q =740.6(2.1) MHz, η=0.07(2) and ν Q =971.5(1.9) MHz, η=0.72(1) characterize 181 Ta and SnO and SnO 2 , respectively. (orig.)

  13. On the physics of dispersive electron transport characteristics in SnO2 nanoparticle-based dye sensitized solar cells.

    Science.gov (United States)

    Ashok, Aditya; Vijayaraghavan, S N; Unni, Gautam E; Nair, Shantikumar V; Shanmugam, Mariyappan

    2018-04-27

    The present study elucidates dispersive electron transport mediated by surface states in tin oxide (SnO 2 ) nanoparticle-based dye sensitized solar cells (DSSCs). Transmission electron microscopic studies on SnO 2 show a distribution of ∼10 nm particles exhibiting (111) crystal planes with inter-planar spacing of 0.28 nm. The dispersive transport, experienced by photo-generated charge carriers in the bulk of SnO 2 , is observed to be imposed by trapping and de-trapping processes via SnO 2 surface states present close to the band edge. The DSSC exhibits 50% difference in performance observed between the forward (4%) and reverse (6%) scans due to the dispersive transport characteristics of the charge carriers in the bulk of the SnO 2 . The photo-generated charge carriers are captured and released by the SnO 2 surface states that are close to the conduction band-edge resulting in a very significant variation; this is confirmed by the hysteresis observed in the forward and reverse scan current-voltage measurements under AM1.5 illumination. The hysteresis behavior assures that the charge carriers are accumulated in the bulk of electron acceptor due to the trapping, and released by de-trapping mediated by surface states observed during the forward and reverse scan measurements.

  14. On the physics of dispersive electron transport characteristics in SnO2 nanoparticle-based dye sensitized solar cells

    Science.gov (United States)

    Ashok, Aditya; Vijayaraghavan, S. N.; Unni, Gautam E.; Nair, Shantikumar V.; Shanmugam, Mariyappan

    2018-04-01

    The present study elucidates dispersive electron transport mediated by surface states in tin oxide (SnO2) nanoparticle-based dye sensitized solar cells (DSSCs). Transmission electron microscopic studies on SnO2 show a distribution of ˜10 nm particles exhibiting (111) crystal planes with inter-planar spacing of 0.28 nm. The dispersive transport, experienced by photo-generated charge carriers in the bulk of SnO2, is observed to be imposed by trapping and de-trapping processes via SnO2 surface states present close to the band edge. The DSSC exhibits 50% difference in performance observed between the forward (4%) and reverse (6%) scans due to the dispersive transport characteristics of the charge carriers in the bulk of the SnO2. The photo-generated charge carriers are captured and released by the SnO2 surface states that are close to the conduction band-edge resulting in a very significant variation; this is confirmed by the hysteresis observed in the forward and reverse scan current-voltage measurements under AM1.5 illumination. The hysteresis behavior assures that the charge carriers are accumulated in the bulk of electron acceptor due to the trapping, and released by de-trapping mediated by surface states observed during the forward and reverse scan measurements.

  15. Highly sensitive SnO2 sensor via reactive laser-induced transfer

    Science.gov (United States)

    Palla Papavlu, Alexandra; Mattle, Thomas; Temmel, Sandra; Lehmann, Ulrike; Hintennach, Andreas; Grisel, Alain; Wokaun, Alexander; Lippert, Thomas

    2016-04-01

    Gas sensors based on tin oxide (SnO2) and palladium doped SnO2 (Pd:SnO2) active materials are fabricated by a laser printing method, i.e. reactive laser-induced forward transfer (rLIFT). Thin films from tin based metal-complex precursors are prepared by spin coating and then laser transferred with high resolution onto sensor structures. The devices fabricated by rLIFT exhibit low ppm sensitivity towards ethanol and methane as well as good stability with respect to air, moisture, and time. Promising results are obtained by applying rLIFT to transfer metal-complex precursors onto uncoated commercial gas sensors. We could show that rLIFT onto commercial sensors is possible if the sensor structures are reinforced prior to printing. The rLIFT fabricated sensors show up to 4 times higher sensitivities then the commercial sensors (with inkjet printed SnO2). In addition, the selectivity towards CH4 of the Pd:SnO2 sensors is significantly enhanced compared to the pure SnO2 sensors. Our results indicate that the reactive laser transfer technique applied here represents an important technical step for the realization of improved gas detection systems with wide-ranging applications in environmental and health monitoring control.

  16. Broad compositional tunability of indium tin oxide nanowires grown by the vapor-liquid-solid mechanism

    Directory of Open Access Journals (Sweden)

    M. Zervos

    2014-05-01

    Full Text Available Indium tin oxide nanowires were grown by the reaction of In and Sn with O2 at 800 °C via the vapor-liquid-solid mechanism on 1 nm Au/Si(001. We obtain Sn doped In2O3 nanowires having a cubic bixbyite crystal structure by using In:Sn source weight ratios > 1:9 while below this we observe the emergence of tetragonal rutile SnO2 and suppression of In2O3 permitting compositional and structural tuning from SnO2 to In2O3 which is accompanied by a blue shift of the photoluminescence spectrum and increase in carrier lifetime attributed to a higher crystal quality and Fermi level position.

  17. Novel microwave-assisted synthesis of porous g-C3N4/SnO2 nanocomposite for solar water-splitting

    Science.gov (United States)

    Seza, A.; Soleimani, F.; Naseri, N.; Soltaninejad, M.; Montazeri, S. M.; Sadrnezhaad, S. K.; Mohammadi, M. R.; Moghadam, H. Asgari; Forouzandeh, M.; Amin, M. H.

    2018-05-01

    Highly porous nanocomposites of graphitic-carbon nitride and tin oxide (g-C3N4/SnO2) were prepared through simple pyrolysis of urea molecules under microwave irradiation. The initial amount of tin was varied in order to investigate the effect of SnO2 content on preparation and properties of the composites. The synthesized nanocomposites were well-characterized by XRD, FE-SEM, HR-TEM, BET, FTIR, XPS, DRS, and PL. A homogeneous distribution of SnO2 nanoparticles with the size of less than 10 nm on the porous C3N4 sheets could be obtained, suggesting that in-situ synthesis of SnO2 nanoparticles was responsible for the formation of g-C3N4. The process likely occurred by the aid of the large amounts of OH groups formed on the surfaces of SnO2 nanoparticles during the polycondensation reactions of tin derivatives which could facilitate the pyrolysis of urea to carbon nitride. The porous nanocomposite prepared with initial tin amount of 0.175 g had high specific surface area of 195 m2 g-1 which showed high efficiency photoelectrochemical water-splitting ability. A maximum photocurrent density of 33 μA cm-2 was achieved at an applied potential of 0.5 V when testing this nanocomposite as photo-anode in water-splitting reactions under simulated visible light irradiation, introducing it as a promising visible light photoactive material.

  18. Demonstration of high-performance p-type tin oxide thin-film transistors using argon-plasma surface treatments

    Science.gov (United States)

    Bae, Sang-Dae; Kwon, Soo-Hun; Jeong, Hwan-Seok; Kwon, Hyuck-In

    2017-07-01

    In this work, we investigated the effects of low-temperature argon (Ar)-plasma surface treatments on the physical and chemical structures of p-type tin oxide thin-films and the electrical performance of p-type tin oxide thin-film transistors (TFTs). From the x-ray photoelectron spectroscopy measurement, we found that SnO was the dominant phase in the deposited tin oxide thin-film, and the Ar-plasma treatment partially transformed the tin oxide phase from SnO to SnO2 by oxidation. The resistivity of the tin oxide thin-film increased with the plasma-treatment time because of the reduced hole concentration. In addition, the root-mean-square roughness of the tin oxide thin-film decreased as the plasma-treatment time increased. The p-type oxide TFT with an Ar-plasma-treated tin oxide thin-film exhibited excellent electrical performance with a high current on-off ratio (5.2 × 106) and a low off-current (1.2 × 10-12 A), which demonstrates that the low-temperature Ar-plasma treatment is a simple and effective method for improving the electrical performance of p-type tin oxide TFTs.

  19. Growth of Fe2O3/SnO2 nanobelt arrays on iron foil for efficient photocatalytic degradation of methylene blue

    Science.gov (United States)

    Lei, Rui; Ni, Hongwei; Chen, Rongsheng; Zhang, Bowei; Zhan, Weiting; Li, Yang

    2017-04-01

    Tin(IV) oxide has been intensively employed in optoelectronic devices due to its excellent electrical and optical properties. But the high recombination rates of the photogenerated electron-hole pairs of SnO2 nanomaterials often results in low photocatalytic efficiency. Herein, we proposed a facile route to prepare a novel Fe2O3/SnO2 heterojunction structure. The nanobelt arrays grown on iron foil naturally form a Schottky-type contact and provide a direct pathway for the photogenerated excitons. Hence, the Fe2O3/SnO2 nanobelt arrays exhibit much improved photocatalytic performance with the degradation rate constant on the Fe2O3/SnO2 film of approximately 12 times to that of α-Fe2O3 nanobelt arrays.

  20. Enhanced cyclic performance and lithium storage capacity of SnO2/graphene nanoporous electrodes with three-dimensionally delaminated flexible structure.

    Science.gov (United States)

    Paek, Seung-Min; Yoo, EunJoo; Honma, Itaru

    2009-01-01

    To fabricate nanoporous electrode materials with delaminated structure, the graphene nanosheets (GNS) in the ethylene glycol solution were reassembled in the presence of rutile SnO(2) nanoparticles. According to the TEM analysis, the graphene nanosheets are homogeneously distributed between the loosely packed SnO(2) nanoparticles in such a way that the nanoporous structure with a large amount of void spaces could be prepared. The obtained SnO(2)/GNS exhibits a reversible capacity of 810 mAh/g; furthermore, its cycling performance is drastically enhanced in comparison with that of the bare SnO(2) nanoparticle. After 30 cycles, the charge capacity of SnO(2)/GNS still remained 570 mAh/g, that is, about 70% retention of the reversible capacity, while the specific capacity of the bare SnO(2) nanoparticle on the first charge was 550 mAh/g, dropping rapidly to 60 mAh/g only after 15 cycles. The dimensional confinement of tin oxide nanoparticles by the surrounding GNS limits the volume expansion upon lithium insertion, and the developed pores between SnO(2) and GNS could be used as buffered spaces during charge/discharge, resulting in the superior cyclic performances.

  1. Morphology and phase transformations of tin oxide nanostructures synthesized by the hydrothermal method in the presence of dicarboxylic acids

    International Nuclear Information System (INIS)

    Zima, Tatyana; Bataev, Ivan

    2016-01-01

    A new approach to the synthesis of non-stoichiometric tin oxide structures with different morphologies and the phase compositions has been evaluated. The nanostructures were synthesized by hydrothermal treatment of the mixtures of dicarboxylic acids ― aminoterephthalic or oxalic ― with nanocrystalline SnO 2 powder, which was obtained via the sol-gel technology. The products were characterized by Raman and IR spectroscopy, SEM, HRTEM, and XRD analysis. It was shown that the controlled addition of a dicarboxylic acid leads not only to a change in the morphology of the nanostructures, but also to SnO 2 –SnO 2 /Sn 3 O 4 –Sn 3 O 4 –SnO phase transformations. A single-phase Sn 3 O 4 in the form of the well-separated hexagonal nanoplates and mixed SnO 2 /Sn 3 O 4 phases in the form of hierarchical flower-like structures were obtained in the presence of organic additives. The effects of concentration, redox activity of the acids and heat treatment on the basic characteristics of the synthesized tin oxide nanostructures and phase transformations in the synthesized materials are discussed. - Graphical abstract: The controlled addition of aminoterephthalic or oxalic acid leads not only to a change in the morphology of the nanostructures, but also to SnO 2 –SnO 2 /Sn 3 O 4 –Sn 3 O 4 –SnO phase transformations. - Highlights: • A new approach to the synthesis of non-stoichiometric tin oxide structures is studied. • Tin oxide structures are synthesized via hydrothermal method with dicarboxylic acids. • Morphology and phase composition are changed with redox activity and dosage of acid. • The redox activity of acid has an effect on ratio of SnO and SnO 2 in crystal structure. • A pure phase Sn 3 O 4 nanoplates and SnO 2 /Sn 3 O 4 hierarchical structures are formed.

  2. LPG sensing characteristics of electrospray deposited SnO2 nanoparticles

    International Nuclear Information System (INIS)

    Gürbüz, Mevlüt; Günkaya, Göktuğ; Doğan, Aydın

    2014-01-01

    Highlights: • SnO 2 nanopowder was deposited on conductive substrates using ESD technique. • Solution flow rate, coating time, substrate–nozzle distance and solid/alcohol ratio were studied to optimize SnO 2 film structure. • The gas sensing properties of tin oxide films were investigated using LPG. • The sensitivity of the films was increased with operating temperature. • The best sensitivity was observed for 20 LEL LPG at 450 °C operating temperature. - Abstract: In this study, SnO 2 films were fabricated on conductive substrate such as aluminum and platinum coated alumina using electro-spray deposition (ESD) method for gas sensor applications. Solution flow rate, coating time, substrate–nozzle distance and solid/alcohol ratio were studied to optimize SnO 2 film structure. The morphology of the deposited films was characterized by stereo and scanning electron microscopy (SEM). The gas sensing properties of tin oxide films were investigated using liquid petroleum gas (LPG) for various lower explosive limit (LEL). The results obtained from microscopic analyses show that optimum SnO 2 films were evaluated at flow rate of 0.05 ml/min, at distance of 6 cm, for 10 min deposition time, for 20 gSnO 2 /L ethanol ratio and at 7 kV DC electric field. By the results obtained from the gas sensing behavior, the sensitivity of the films was increased with operating temperature. The films showed better sensitivity for 20 LEL LPG concentration at 450 °C operating temperature

  3. Amplified electrochemical determination of maltol in food based on graphene oxide-wrapped tin oxide@carbon nanospheres.

    Science.gov (United States)

    Gan, Tian; Sun, Junyong; Yu, Miaomiao; Wang, Kaili; Lv, Zhen; Liu, Yanming

    2017-01-01

    The study presents a new approach for rapid and ultrasensitive detection of maltol using a glassy carbon electrode (GCE) modified with graphene oxide-wrapped tin oxide@carbon nanospheres (SnO2@C@GO). The morphological and components properties of SnO2@C@GO nanocomposites were investigated by means of X-ray diffraction spectroscopy, Raman spectroscopy, field emission scanning electron microscopy, high resolution transmission electron microscopy, and electrochemical impedance spectroscopy. SnO2@C@GO nanocomposite on a GCE had a synergetic effect on the electrochemical oxidation of maltol by means of square wave voltammetry. Under the optimum conditions, anodic peak current response of maltol was linear with its concentration in the range of 80nM-10μM, and a detection limit of 12nM was achieved for maltol. The experiment results presented that the method showed good selectivity, sensitivity, reproducibility, and long-term stability, as well as excellent potential for use as an ideal inexpensive voltammetric method applicable for complex food matrices. Copyright © 2016 Elsevier Ltd. All rights reserved.

  4. Facile mechanochemical synthesis of nano SnO2/graphene composite from coarse metallic Sn and graphite oxide: an outstanding anode material for lithium-ion batteries.

    Science.gov (United States)

    Ye, Fei; Zhao, Bote; Ran, Ran; Shao, Zongping

    2014-04-01

    A facile method for the large-scale synthesis of SnO2 nanocrystal/graphene composites by using coarse metallic Sn particles and cheap graphite oxide (GO) as raw materials is demonstrated. This method uses simple ball milling to realize a mechanochemical reaction between Sn particles and GO. After the reaction, the initial coarse Sn particles with sizes of 3-30 μm are converted to SnO2 nanocrystals (approximately 4 nm) while GO is reduced to graphene. Composite with different grinding times (1 h 20 min, 2 h 20 min or 8 h 20 min, abbreviated to 1, 2 or 8 h below) and raw material ratios (Sn:GO, 1:2, 1:1, 2:1, w/w) are investigated by X-ray diffraction, X-ray photoelectron spectroscopy, field-emission scanning electron microscopy and transmission electron microscopy. The as-prepared SnO2 /graphene composite with a grinding time of 8 h and raw material ratio of 1:1 forms micrometer-sized architected chips composed of composite sheets, and demonstrates a high tap density of 1.53 g cm(-3). By using such composites as anode material for LIBs, a high specific capacity of 891 mA h g(-1) is achieved even after 50 cycles at 100 mA g(-1). © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Nanocrystalline SnO2:F Thin Films for Liquid Petroleum Gas Sensors

    Directory of Open Access Journals (Sweden)

    Sutichai Chaisitsak

    2011-07-01

    Full Text Available This paper reports the improvement in the sensing performance of nanocrystalline SnO2-based liquid petroleum gas (LPG sensors by doping with fluorine (F. Un-doped and F-doped tin oxide films were prepared on glass substrates by the dip-coating technique using a layer-by-layer deposition cycle (alternating between dip-coating a thin layer followed by a drying in air after each new layer. The results showed that this technique is superior to the conventional technique for both improving the film thickness uniformity and film transparency. The effect of F concentration on the structural, surface morphological and LPG sensing properties of the SnO2 films was investigated. Atomic Force Microscopy (AFM and X-ray diffraction pattern measurements showed that the obtained thin films are nanocrystalline SnO2 with nanoscale-textured surfaces. Gas sensing characteristics (sensor response and response/recovery time of the SnO2:F sensors based on a planar interdigital structure were investigated at different operating temperatures and at different LPG concentrations. The addition of fluorine to SnO2 was found to be advantageous for efficient detection of LPG gases, e.g., F-doped sensors are more stable at a low operating temperature (300 °C with higher sensor response and faster response/recovery time, compared to un-doped sensor materials. The sensors based on SnO2:F films could detect LPG even at a low level of 25% LEL, showing the possibility of using this transparent material for LPG leak detection.

  6. Spectroscopic and luminescent properties of Co2+ doped tin oxide thin films by spray pyrolysis

    Directory of Open Access Journals (Sweden)

    K. Durga Venkata Prasad

    2016-07-01

    Full Text Available The wide variety of electronic and chemical properties of metal oxides makes them exciting materials for basic research and for technological applications alike. Oxides span a wide range of electrical properties from wide band-gap insulators to metallic and superconducting. Tin oxide belongs to a class of materials called Transparent Conducting Oxides (TCO which constitutes an important component for optoelectronic applications. Co2+ doped tin oxide thin films were prepared by chemical spray pyrolysis synthesis and characterized by powder X-ray diffraction, SEM, TEM, FT-IR, optical, EPR and PL techniques to collect the information about the crystal structure, coordination/local site symmetry of doped Co2+ ions in the host lattice and the luminescent properties of the prepared sample. Powder XRD data revealed that the crystal structure belongs to tetragonal rutile phase and its lattice cell parameters are evaluated. The average crystallite size was estimated to be 26 nm. The morphology of prepared sample was analyzed by using SEM and TEM studies. Functional groups of the prepared sample were observed in the FT-IR spectrum. Optical absorption and EPR studies have shown that on doping, Co2+ ions enter in the host lattice as octahedral site symmetry. PL studies of Co2+ doped SnO2 thin films exhibit blue and yellow emission bands. CIE chromaticity coordinates were also calculated from emission spectrum of Co2+ doped SnO2 thin films.

  7. Atomic-Layer-Deposited SnO2 as Gate Electrode for Indium-Free Transparent Electronics

    KAUST Repository

    Alshammari, Fwzah Hamud

    2017-08-04

    Atomic-layer-deposited SnO2 is used as a gate electrode to replace indium tin oxide (ITO) in thin-film transistors and circuits for the first time. The SnO2 films deposited at 200 °C show low electrical resistivity of ≈3.1 × 10−3 Ω cm with ≈93% transparency in most of the visible range of the electromagnetic spectrum. Thin-film transistors fabricated with SnO2 gates show excellent transistor properties including saturation mobility of 15.3 cm2 V−1 s−1, a low subthreshold swing of ≈130 mV dec−1, a high on/off ratio of ≈109, and an excellent electrical stability under constant-voltage stressing conditions to the gate terminal. Moreover, the SnO2-gated thin-film transistors show excellent electrical characteristics when used in electronic circuits such as negative channel metal oxide semiconductor (NMOS) inverters and ring oscillators. The NMOS inverters exhibit a low propagation stage delay of ≈150 ns with high DC voltage gain of ≈382. A high oscillation frequency of ≈303 kHz is obtained from the output sinusoidal signal of the 11-stage NMOS inverter-based ring oscillators. These results show that SnO2 can effectively replace ITO in transparent electronics and sensor applications.

  8. Identification of vacancy defect complexes in transparent semiconducting oxides ZnO, In2O3 and SnO2

    International Nuclear Information System (INIS)

    Makkonen, Ilja; Korhonen, Esa; Prozheeva, Vera; Tuomisto, Filip

    2016-01-01

    Positron annihilation spectroscopy, when combined with supporting high-quality modeling of positron states and annihilation in matter, is a powerful tool for detailed defect identification of vacancy-type defects in semiconductors and oxides. Here we demonstrate that the Doppler broadening of the positron annihilation radiation is a very sensitive means for observing the oxygen environment around cation vacancies, the main open-volume defects trapping positrons in measurements made for transparent semiconducting oxides. Changes in the positron annihilation signal due to external manipulation such as irradiation and annealing can be correlated with the associated changes in the sizes of the detected vacancy clusters. Our examples for ZnO, In 2 O 3 and SnO 2 demonstrate that oxygen vacancies in oxides can be detected directly using positron annihilation spectroscopy when they are complexed with cation vacancies. (paper)

  9. Identification of vacancy defect complexes in transparent semiconducting oxides ZnO, In2O3 and SnO2

    Science.gov (United States)

    Makkonen, Ilja; Korhonen, Esa; Prozheeva, Vera; Tuomisto, Filip

    2016-06-01

    Positron annihilation spectroscopy, when combined with supporting high-quality modeling of positron states and annihilation in matter, is a powerful tool for detailed defect identification of vacancy-type defects in semiconductors and oxides. Here we demonstrate that the Doppler broadening of the positron annihilation radiation is a very sensitive means for observing the oxygen environment around cation vacancies, the main open-volume defects trapping positrons in measurements made for transparent semiconducting oxides. Changes in the positron annihilation signal due to external manipulation such as irradiation and annealing can be correlated with the associated changes in the sizes of the detected vacancy clusters. Our examples for ZnO, In2O3 and SnO2 demonstrate that oxygen vacancies in oxides can be detected directly using positron annihilation spectroscopy when they are complexed with cation vacancies.

  10. Facile Synthesis of Mesocrystalline SnO2 Nanorods on Reduced Graphene Oxide Sheets: An Appealing Multifunctional Affinity Probe for Sequential Enrichment of Endogenous Peptides and Phosphopeptides.

    Science.gov (United States)

    Ma, Wen; Zhang, Feng; Li, Liping; Chen, Shuai; Qi, Limin; Liu, Huwei; Bai, Yu

    2016-12-28

    A novel multifunctional composite comprising mesocrystalline SnO 2 nanorods (NRs) vertically aligned on reduced graphene oxide (rGO) sheets was synthesized and developed for sequential capture of endogenous peptides and phosphopeptides. With the hydrophobicity of rGO and high affinity of SnO 2 nanorods, sequential enrichment of endogenous peptides and phosphopeptides could be easily achieved through a modulation of elution buffer. With this multifunctional nanomaterial, 36 peptides were observed from diluted bovine serum albumin (BSA) tryptic digest and 4 phosphopeptides could be selectively captured from β-casein digest. The detection limit of tryptic digest of β-casein was low to 4 × 10 -10 M, and the selectivity was up to 1:500 (molar ratio of β-casein and BSA digest). The effectiveness and robustness of rGO-SnO 2 NRs in a complex biological system was also confirmed by using human serum as a real sample. Our work is promising for small peptide enrichment and identification especially in complicated biological sample preparation, which also opens a new perspective in the design of multifunctional affinity probes for proteome or peptidome.

  11. An alternative fluorine precursor for the synthesis of SnO2:F by spray pyrolysis

    International Nuclear Information System (INIS)

    Arca, E.; Fleischer, K.; Shvets, I.V.

    2012-01-01

    An alternative, non-toxic precursor was employed for the synthesis of SnO 2 :F transparent conducting oxide. The performance of benzenesulfonyl fluoride (BSF) as F source for spray pyrolysis was investigated. Its decomposition and the actual incorporation of fluorine in the tin oxide matrix were confirmed by X-ray photoelectron spectroscopy while its effect on the electrical properties was investigated by resistance and Hall measurements. Results were compared with respect to samples grown using a common fluorine source (NH 4 F), a commercial available sample and a sample grown by spray pyrolysis at an independent laboratory. We show that BSF leads to actively doped conductive SnO 2 with good carrier mobility, though the fluorine incorporation rate and hence overall conductivity of the films is lower than for fluorine precursors commonly used in spray pyrolysis.

  12. Photo-Induced conductivity of heterojunction GaAs/Rare-Earth doped SnO2

    Directory of Open Access Journals (Sweden)

    Cristina de Freitas Bueno

    2013-01-01

    Full Text Available Rare-earth doped (Eu3+ or Ce3+ thin layers of tin dioxide (SnO2 are deposited by the sol-gel-dip-coating technique, along with gallium arsenide (GaAs films, deposited by the resistive evaporation technique. The as-built heterojunction has potential application in optoelectronic devices, because it may combine the emission from the rare-earth-doped transparent oxide, with a high mobility semiconductor. Trivalent rare-earth-doped SnO2 presents very efficient emission in a wide wavelength range, including red (in the case of Eu3+ or blue (Ce3+. The advantage of this structure is the possibility of separation of the rare-earth emission centers, from the electron scattering, leading to an indicated combination for electroluminescence. Electrical characterization of the heterojunction SnO2:Eu/GaAs shows a significant conductivity increase when compared to the conductivity of the individual films. Monochromatic light excitation shows up the role of the most external layer, which may act as a shield (top GaAs, or an ultraviolet light absorber sink (top RE-doped SnO2. The observed improvement on the electrical transport properties is probably related to the formation of short conduction channels in the semiconductors junction with two-dimensional electron gas (2DEG behavior, which are evaluated by excitation with distinct monochromatic light sources, where the samples are deposited by varying the order of layer deposition.

  13. MAPLE deposition and characterization of SnO2 colloidal nanoparticle thin films

    International Nuclear Information System (INIS)

    Caricato, A P; Martino, M; Romano, F; Tunno, T; Valerini, D; Epifani, M; Rella, R; Taurino, A

    2009-01-01

    In this paper we report on the deposition and characterization of tin oxide (SnO 2 ) nanoparticle thin films. The films were deposited by the matrix-assisted pulsed laser evaporation (MAPLE) technique. SnO 2 colloidal nanoparticles with a trioctylphosphine capping layer were diluted in toluene with a concentration of 0.2 wt% and frozen at liquid nitrogen temperature. The frozen target was irradiated with a KrF (248 nm, τ = 20 ns) excimer laser (6000 pulses at 10 Hz). The nanoparticles were deposited on silica (SiO 2 ) and (1 0 0) Si substrates and submitted to morphological (high resolution scanning electron microscopy (SEM)), structural Fourier transform infrared spectroscopy (FTIR) and optical (UV-Vis transmission) characterizations. SEM and FTIR analyses showed that trioctylphosphine was the main component in the as-deposited films. The trioctylphosphine was removed after an annealing in vacuum at 400 0 C, thus allowing to get uniform SnO 2 nanoparticle films in which the starting nanoparticle dimensions were preserved. The energy gap value, determined by optical characterizations, was 4.2 eV, higher than the bulk SnO 2 energy gap (3.6 eV), due to quantum confinement effects.

  14. Analysis of Methanol Sensitivity on SnO2-ZnO Nanocomposite

    Science.gov (United States)

    Bassey, Enobong E.; Sallis, Philip; Prasad, Krishnamachar

    This research reports on the sensing behavior of a nanocomposite of tin dioxide (SnO2) and zinc oxide (ZnO). SnO2-ZnO nanocomposites were fabricated into sensor devices by the radio frequency sputtering method, and used for the characterization of the sensitivity behavior of methanol vapor. The sensor devices were subjected to methanol concentration of 200 ppm at operating temperatures of 150, 250 and 350 °C. A fractional difference model was used to normalize the sensor response, and determine the sensitivity of methanol on the sensor. Response analysis of the SnO2-ZnO sensors to the methanol was most sensitive at 350 °C, followed by 250 and 150 °C. Supported by the morphology (FE-SEM, AFM) analyses of the thin films, the sensitivity behavior confirmed that the nanoparticles of coupled SnO2 and ZnO nanocomposites can promote the charge transportation, and be used to fine-tune the sensitivity of methanol and sensor selectivity to a desired target gas.

  15. Optoelectronic properties of SnO2 thin films sprayed at different deposition times

    Science.gov (United States)

    Allag, Abdelkrim; Saâd, Rahmane; Ouahab, Abdelouahab; Attouche, Hafida; Kouidri, Nabila

    2016-04-01

    This article presents the elaboration of tin oxide (SnO2) thin films on glass substrates by using a home-made spray pyrolysis system. Effects of film thickness on the structural, optical, and electrical film properties are investigated. The films are characterized by several techniques such as x-ray diffraction (XRD), atomic force microscopy (AFM), ultraviolet-visible (UV-Vis) transmission, and four-probe point measurements, and the results suggest that the prepared films are uniform and well adherent to the substrates. X-ray diffraction (XRD) patterns show that SnO2 film is of polycrystal with cassiterite tetragonal crystal structure and a preferential orientation along the (110) plane. The calculated grain sizes are in a range from 32.93 nm to 56.88 nm. Optical transmittance spectra of the films show that their high transparency average transmittances are greater than 65% in the visible region. The optical gaps of SnO2 thin films are found to be in a range of 3.64 eV-3.94 eV. Figures of merit for SnO2 thin films reveal that their maximum value is about 1.15 × 10-4 Ω-1 at λ = 550 nm. Moreover, the measured electrical resistivity at room temperature is on the order of 10-2 Ω·cm.

  16. Optoelectronic properties of SnO2 thin films sprayed at different deposition times

    International Nuclear Information System (INIS)

    Abdelkrim, Allag; Rahmane, Saâd; Abdelouahab, Ouahab; Hafida, Attouche; Nabila, Kouidri

    2016-01-01

    This article presents the elaboration of tin oxide (SnO 2 ) thin films on glass substrates by using a home-made spray pyrolysis system. Effects of film thickness on the structural, optical, and electrical film properties are investigated. The films are characterized by several techniques such as x-ray diffraction (XRD), atomic force microscopy (AFM), ultraviolet-visible (UV–Vis) transmission, and four-probe point measurements, and the results suggest that the prepared films are uniform and well adherent to the substrates. X-ray diffraction (XRD) patterns show that SnO 2 film is of polycrystal with cassiterite tetragonal crystal structure and a preferential orientation along the (110) plane. The calculated grain sizes are in a range from 32.93 nm to 56.88 nm. Optical transmittance spectra of the films show that their high transparency average transmittances are greater than 65% in the visible region. The optical gaps of SnO 2 thin films are found to be in a range of 3.64 eV–3.94 eV. Figures of merit for SnO 2 thin films reveal that their maximum value is about 1.15 × 10 −4 Ω −1 at λ = 550 nm. Moreover, the measured electrical resistivity at room temperature is on the order of 10 −2 Ω·cm. (paper)

  17. One-Dimensional SnO2 Nano structures: Synthesis and Applications

    International Nuclear Information System (INIS)

    Pan, J.; Shen, H.; Mathur, S.; Pan, J.

    2012-01-01

    Nano scale semiconducting materials such as quantum dots (0-dimensional) and one-dimensional (1D) structures, like nano wires, nano belts, and nano tubes, have gained tremendous attention within the past decade. Among the variety of 1D nano structures, tin oxide (SnO 2 ) semiconducting nano structures are particularly interesting because of their promising applications in optoelectronic and electronic devices due to both good conductivity and transparence in the visible region. This article provides a comprehensive review of the recent research activities that focus on the rational synthesis and unique applications of 1D SnO 2 nano structures and their optical and electrical properties. We begin with the rational design and synthesis of 1D SnO 2 nano structures, such as nano tubes, nano wires, nano belts, and some heterogeneous nano structures, and then highlight a range of applications (e.g., gas sensor, lithium-ion batteries, and nano photonics) associated with them. Finally, the review is concluded with some perspectives with respect to future research on 1D SnO 2 nano structures

  18. Structural and optical characterization of p-type highly Fe-doped SnO2 thin films and tunneling transport on SnO2:Fe/p-Si heterojunction

    Science.gov (United States)

    Ben Haj Othmen, Walid; Ben Hamed, Zied; Sieber, Brigitte; Addad, Ahmed; Elhouichet, Habib; Boukherroub, Rabah

    2018-03-01

    Nanocrystalline highly Fe-doped SnO2 thin films were prepared using a new simple sol-gel method with iron amounts of 5, 10, 15 and 20%. The obtained gel offers a long durability and high quality allowing to reach a sub-5 nm nanocrystalline size with a good crystallinity. The films were structurally characterized through X-ray diffraction (XRD) that confirms the formation of rutile SnO2. High Resolution Transmission Electron Microscopy (HRTEM) images reveals the good crystallinity of the nanoparticles. Raman spectroscopy shows that the SnO2 rutile structure is maintained even for high iron concentration. The variation of the PL intensity with Fe concentration reveals that iron influences the distribution of oxygen vacancies in tin oxide. The optical transmittance results indicate a redshift of the SnO2 band gap when iron concentration increases. The above optical results lead us to assume the presence of a compensation phenomenon between oxygen vacancies and introduced holes following Fe doping. From current-voltage measurements, an inversion of the conduction type from n to p is strongly predicted to follow the iron addition. Electrical characterizations of SnO2:Fe/p-Si and SnO2:Fe/n-Si heterojunctions seem to be in accordance with this deduction. The quantum tunneling mechanism is expected to be important at high Fe doping level, which was confirmed by current-voltage measurements at different temperatures. Both optical and electrical properties of the elaborated films present a particularity for the same iron concentration and adopt similar tendencies with Fe amount, which strongly correlate the experimental observations. In order to evaluate the applicability of the elaborated films, we proceed to the fabrication of the SnO2:Fe/SnO2 homojunction for which we note a good rectifying behavior.

  19. The role of MgCl2 compounds in preparation of Tin oxide micro particles by one-step solid - state chemical reaction method and characterization of microstructure

    International Nuclear Information System (INIS)

    Hojabry, A.; Rezainik, Y.; Abdoljavad, N.; Moghimi, N.; Shakib, M.

    2007-01-01

    In this paper, Tin oxide (SnO 2 ) nano crystals have been synthesized by one-step solid-state chemical reactions method. In the first step, the powder of SnCl 4 . 5H 2 O was mixed with MgCl 2 and Mg(OH) 2 with a weight ratio of Sn to Mg (2:1) in the air atmosphere at room, and then annealed at 200 d egree C , 400 d egree C and 600 d egree C in air for 4 h to give different size of nanoparticles. This method is a simple, efficient and economic preparation for SnO 2 nanoparticles with adjustable grain sizes in the range of 7-32 nm in high yield. The microstructure and morphology of SnO 2 nanoparticles have been studied by X-ray diffraction (XRD), scanning electron microscopy and thermal analysis (thermogravimetric analysis -differential thermal analysis).

  20. Microwave-Synthesized Tin Oxide Nanocrystals for Low-Temperature Solution-Processed Planar Junction Organo-Halide Perovskite Solar Cells

    KAUST Repository

    Abulikemu, Mutalifu

    2017-03-25

    Tin oxide has been demonstrate to possess outstanding optoelectronic properties such as optical transparency and high electron mobility, therefore, it was successfully utilized as electron transporting layer in various kind of solar cells. In this study, for the first time, highly dispersible SnO2 nanoparticles were synthesized by microwave-assisted non-aqueous sol-gel route in an organic medium. Ethanol dispersion of the as-prepared nanoparticles was used to cast an uniform thin layer of SnO2 without the aid of aggregating agent and at low temperatures. Organohalide perovskite solar cells were fabricated using SnO2 as electron transporting layer. Morphological and spectroscopic investigations, in addition to the good photoconversion efficiency obtained evidenced that nanoparticles synthesized by this route have optimal properties such small size and crystallinity to form a continuous film, furthermore, this method allows high reproducibility and scalability of the film deposition process.

  1. Microwave-Synthesized Tin Oxide Nanocrystals for Low-Temperature Solution-Processed Planar Junction Organo-Halide Perovskite Solar Cells

    KAUST Repository

    Abulikemu, Mutalifu; Neophytou, Marios; Barbe, Jeremy; Tietze, Max Lutz; El Labban, Abdulrahman; Anjum, Dalaver H.; Amassian, Aram; McCulloch, Iain; Del Gobbo, Silvano

    2017-01-01

    Tin oxide has been demonstrate to possess outstanding optoelectronic properties such as optical transparency and high electron mobility, therefore, it was successfully utilized as electron transporting layer in various kind of solar cells. In this study, for the first time, highly dispersible SnO2 nanoparticles were synthesized by microwave-assisted non-aqueous sol-gel route in an organic medium. Ethanol dispersion of the as-prepared nanoparticles was used to cast an uniform thin layer of SnO2 without the aid of aggregating agent and at low temperatures. Organohalide perovskite solar cells were fabricated using SnO2 as electron transporting layer. Morphological and spectroscopic investigations, in addition to the good photoconversion efficiency obtained evidenced that nanoparticles synthesized by this route have optimal properties such small size and crystallinity to form a continuous film, furthermore, this method allows high reproducibility and scalability of the film deposition process.

  2. Tin

    Science.gov (United States)

    Kamilli, Robert J.; Kimball, Bryn E.; Carlin, James F.; Schulz, Klaus J.; DeYoung,, John H.; Seal, Robert R.; Bradley, Dwight C.

    2017-12-19

    Tin (Sn) is one of the first metals to be used by humans. Almost without exception, tin is used as an alloy. Because of its hardening effect on copper, tin was used in bronze implements as early as 3500 B.C. The major uses of tin today are for cans and containers, construction materials, transportation materials, and solder. The predominant ore mineral of tin, by far, is cassiterite (SnO2).In 2015, the world’s total estimated mine production of tin was 289,000 metric tons of contained tin. Total world reserves at the end of 2016 were estimated to be 4,700,000 metric tons. China held about 24 percent of the world’s tin reserves and accounted for 38 percent of the world’s 2015 production of tin.The proportion of scrap used in tin production is between 10 and 25 percent. Unlike many metals, tin recycling is relatively efficient, and the fraction of tin in discarded products that get recycled is greater than 50 percent.Only about 20 percent of the world’s identified tin resources occur as primary hydrothermal hard-rock veins, or lodes. These lodes contain predominantly high-temperature minerals and almost invariably occur in close association with silicic, peraluminous granites. About 80 percent of the world’s identified tin resources occur as unconsolidated secondary or placer deposits in riverbeds and valleys or on the sea floor. The largest concentration of both onshore and offshore placers is in the extensive tin belt of Southeast Asia, which stretches from China in the north, through Thailand, Burma (also referred to as Myanmar), and Malaysia, to the islands of Indonesia in the south. Furthermore, tin placers are almost always found closely allied to the granites from which they originate. Other countries with significant tin resources are Australia, Bolivia, and Brazil.Most hydrothermal tin deposits belong to what can be thought of as a superclass of porphyry-greisen deposits. The hydrothermal tin deposits are all characterized by a close spatial

  3. Synthesis and Characterization of Nanocomposites Tin Oxide-Graphene Doping Pd Using Polyol Method

    Directory of Open Access Journals (Sweden)

    Aminuddin Debataraja

    2018-05-01

    Full Text Available This paper report on polyol method for Pd doped tin oxide-graphene nanocomposite thin film. XRD result shows sharp peaks at certain 2θ value and match with tin oxide, graphene, and Pd database. FTIR result shows peak from alcohol chain for –OH strong bonded absorption (3444 cm-1, also there are aldehyde and ketone which are indicated by C=O strong absorption (1751 cm-1. Moreover, alkene is also formed for decreasing symmetry intensity C=C (1616 cm-1, while alkyne is formed at strong deformation absorption at 646 and 613 cm-1. SEM and TEM result show SnO2 particles are attached uniformly on graphene surface layer. The composition for C, O, Sn, and Pd are 33.13, 25.58, 35.35 and 5.94%, respectively. This result indicated that the good composition is formed for Pd doped SnO2-graphene nanocomposite. The nanocomposite is promising materials for toxic gas sensor application at low temperature.

  4. Selective detection of acetone and hydrogen sulfide for the diagnosis of diabetes and halitosis using SnO(2) nanofibers functionalized with reduced graphene oxide nanosheets.

    Science.gov (United States)

    Choi, Seon-Jin; Jang, Bong-Hoon; Lee, Seo-Jin; Min, Byoung Koun; Rothschild, Avner; Kim, Il-Doo

    2014-02-26

    Sensitive detection of acetone and hydrogen sulfide levels in exhaled human breath, serving as breath markers for some diseases such as diabetes and halitosis, may offer useful information for early diagnosis of these diseases. Exhaled breath analyzers using semiconductor metal oxide (SMO) gas sensors have attracted much attention because they offer low cost fabrication, miniaturization, and integration into portable devices for noninvasive medical diagnosis. However, SMO gas sensors often display cross sensitivity to interfering species. Therefore, selective real-time detection of specific disease markers is a major challenge that must be overcome to ensure reliable breath analysis. In this work, we report on highly sensitive and selective acetone and hydrogen sulfide detection achieved by sensitizing electrospun SnO2 nanofibers with reduced graphene oxide (RGO) nanosheets. SnO2 nanofibers mixed with a small amount (0.01 wt %) of RGO nanosheets exhibited sensitive response to hydrogen sulfide (Rair/Rgas = 34 at 5 ppm) at 200 °C, whereas sensitive acetone detection (Rair/Rgas = 10 at 5 ppm) was achieved by increasing the RGO loading to 5 wt % and raising the operation temperature to 350 °C. The detection limit of these sensors is predicted to be as low as 1 ppm for hydrogen sulfide and 100 ppb for acetone, respectively. These concentrations are much lower than in the exhaled breath of healthy people. This demonstrates that optimization of the RGO loading and the operation temperature of RGO-SnO2 nanocomposite gas sensors enables highly sensitive and selective detection of breath markers for the diagnosis of diabetes and halitosis.

  5. Preparation of catalysts PtSb2O5.SnO2 supported on carbon and ATO using the alcohol reduction method for electrochemical oxidation of ethanol

    International Nuclear Information System (INIS)

    Ayoub, Jamil Mahmoud Said

    2013-01-01

    Pt Sn/C-ATO electrocatalysts with different Pt:Sn atomic ratios (90:10, 70:30 and 50:50) were prepared in a single step by an alcohol-reduction process using H 2 PtCl 6 .6H 2 O and SnCl 2 .2H 2 O as metal sources and ethylene glycol as solvent and reducing agent and a physical mixture of carbon Vulcan XC72 (85 wt%) and Sb 2 O 5 .SnO 2 (15 wt%) as support (C-ATO). The obtained materials were characterized by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The catalytic activity for ethanol electro-oxidation in acid medium was investigated by cyclic voltammetry and chronoamperometry and in single direct ethanol fuel cell (DEFC). XRD analyses showed that Pt(FCC), SnO 2 , carbon and ATO phases coexist in the obtained materials. The electrochemical studies showed that PtSn/C-ATO electrocatalysts were more active for ethanol electro-oxidation than PtSn/C electrocatalyst. The experiments at 100 deg C on a single DEFC showed that the power density of the cell using Pt Sn/C-ATO (90:10) was nearly 100% higher than the one obtained using Pt Sn/C (50:50). FTIR measurements showed that the addition of ATO to Pt Sn/C favors the formation of acetic acid as a product while for PtSn/C acetaldehyde was the principal product formed. (author)

  6. A rapid hydrothermal synthesis of rutile SnO2 nanowires

    International Nuclear Information System (INIS)

    Lupan, O.; Chow, L.; Chai, G.; Schulte, A.; Park, S.; Heinrich, H.

    2009-01-01

    Tin oxide (SnO 2 ) nanowires with rutile structure have been synthesized by a facile hydrothermal method at 98 deg. C. The morphologies and structural properties of the as-grown nanowires/nanoneedles were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction, X-ray diffraction and Raman spectroscopy. The SEM images reveal tetragonal nanowires of about 10-100 μm in length and 50-100 nm in radius. The Raman scattering peaks indicate a typical rutile phase of the SnO 2 . The effects of molar ratio of SnCl 4 to NH 4 OH on the growth mechanism are discussed

  7. Growth kinetics of tin oxide nanocrystals in colloidal suspensions under hydrothermal conditions

    International Nuclear Information System (INIS)

    Lee, Eduardo J.H.; Ribeiro, Caue; Longo, Elson; Leite, Edson R.

    2006-01-01

    Colloidal suspensions of tin oxide nanocrystals were synthesized at room temperature by the hydrolysis reaction of tin chloride (II), in an ethanolic solution. The coarsening kinetics of such nanocrystals was studied by submitting the as-prepared suspensions to hydrothermal treatments at temperatures of 100, 150 and 200 deg. C for periods between 60 and 12,000 min. Transmission electron microscopy (TEM) was used to characterize the samples (i.e. distribution of nanocrystal size, average particle radius and morphology). The results show that the usual Ostwald ripening coarsening mechanism does not fit well the experimental data, which is an indicative that this process is not significant for SnO 2 nanocrystals, in the studied experimental conditions. The morphology evolution of the nanocrystals upon hydrothermal treatment indicates that growth by oriented attachment (OA) should be significant. A kinetic model that describes OA growth is successfully applied to fit the data

  8. Electrochemically active nanocomposites of Li4Ti5O12 2D nanosheets and SnO2 0D nanocrystals with improved electrode performance

    International Nuclear Information System (INIS)

    Han, Song Yi; Kim, In Young; Lee, Sang-Hyup; Hwang, Seong-Ju

    2012-01-01

    Electrochemically active nanocomposites consisting of Li 4 Ti 5 O 12 2D nanosheets and SnO 2 0D nanocrystals are synthesized by the crystal growth of tin dioxide on the surface of 2D nanostructured lithium titanate. According to powder X-ray diffraction and electron microscopic analyses, the rutile-structured SnO 2 nanocrystals are stabilized on the surface of spinel-structured Li 4 Ti 5 O 12 2D nanosheets. The homogeneous hybridization of tin dioxide with lithium titanate is confirmed by elemental mapping analysis. Ti K-edge X-ray absorption near-edge structure and Sn 3d X-ray photoelectron spectroscopy indicate the stabilization of tetravalent titanium ions in the spinel lattice of Li 4 Ti 5 O 12 and the formation of SnO 2 phase with tetravalent Sn oxidation state. The electrochemical measurements clearly demonstrate the promising functionality of the present nanocomposites as anode for lithium secondary batteries. The Li 4 Ti 5 O 12 –SnO 2 nanocomposites show larger discharge capacity and better cyclability than do the uncomposited Li 4 Ti 5 O 12 and SnO 2 phases, indicating the synergistic effect of nanocomposite formation on the electrode performance of Li 4 Ti 5 O 12 and SnO 2 . The present experimental findings underscore the validity of 2D nanostructured lithium titanate as a useful platform for the stabilization of nanocrystalline electrode materials and also for the improvement of their functionality.

  9. Structural, morphological, and optical properties of tin(IV) oxide nanoparticles synthesized using Camellia sinensis extract: a green approach

    Science.gov (United States)

    Selvakumari, J. Celina; Ahila, M.; Malligavathy, M.; Padiyan, D. Pathinettam

    2017-09-01

    Tin oxide (SnO2) nanoparticles were cost-effectively synthesized using nontoxic chemicals and green tea ( Camellia sinensis) extract via a green synthesis method. The structural properties of the obtained nanoparticles were studied using X-ray diffraction, which indicated that the crystallite size was less than 20 nm. The particle size and morphology of the nanoparticles were analyzed using scanning electron microscopy and transmission electron microscopy. The morphological analysis revealed agglomerated spherical nanoparticles with sizes varying from 5 to 30 nm. The optical properties of the nanoparticles' band gap were characterized using diffuse reflectance spectroscopy. The band gap was found to decrease with increasing annealing temperature. The O vacancy defects were analyzed using photoluminescence spectroscopy. The increase in the crystallite size, decreasing band gap, and the increasing intensities of the UV and visible emission peaks indicated that the green-synthesized SnO2 may play future important roles in catalysis and optoelectronic devices.

  10. Characterization and Gas Sensing Properties of Copper-doped Tin Oxide Thin Films Deposited by Ultrasonic Spray Pyrolysis

    Directory of Open Access Journals (Sweden)

    Zhaoxia ZHAI

    2016-05-01

    Full Text Available Tin oxide-based thin films are deposited by ultrasonic spray pyrolysis technology, in which Cu addition is introduced to enhance the gas sensing performance by H2S detection. The thin films are porous and comprise nano-sized crystallites. One of the Cu-containing thin film sensors demonstrates a fast and significant response to H2S gas. The values of power law exponent n are calculated to discuss the sensitivity of the sensors, which is significantly promoted by Cu additive. The sensitivity of Cu-doped SnO2 gas sensors is determined by two mechanisms. One is the normal gas sensing mechanism of SnO2 grains, and the other is the promoted mechanism caused by the transformation between CuO and CuS in the H2S detection. DOI: http://dx.doi.org/10.5755/j01.ms.22.2.12917

  11. The role of surface and deep-level defects on the emission of tin oxide quantum dots

    International Nuclear Information System (INIS)

    Kumar, Vinod; Kumar, Vijay; Som, S; Ntwaeaborwa, O M; Swart, H C; Neethling, J H; Lee, Mike

    2014-01-01

    This paper reports on the role of surface and deep-level defects on the blue emission of tin oxide quantum dots (SnO 2 QDs) synthesized by the solution-combustion method at different combustion temperatures. X-ray diffraction studies showed the formation of a single rutile SnO 2 phase with a tetragonal lattice structure. High resolution transmission electron microscopy studies revealed an increase in the average dot size from 2.2 to 3.6 nm with an increase of the combustion temperature from 350 to 550 °C. A decrease in the band gap value from 3.37 to 2.76 eV was observed with the increase in dot size due to the quantum confinement effect. The photoluminescence emission was measured for excitation at 325 nm and it showed a broad blue emission band for all the combustion temperatures studied. This was due to the creation of various oxygen and tin vacancies/defects as confirmed by x-ray photoelectron spectroscopy data. The origin of the blue emission in the SnO 2 QDs is discussed with the help of an energy band diagram. (paper)

  12. Hydrolysis of bis(dimethylamido)tin to tin (II) oxyhydroxide and its selective transformation into tin (II) or tin (IV) oxide

    KAUST Repository

    Khanderi, Jayaprakash; Shi, Lei; Rothenberger, Alexander

    2015-01-01

    Sn6O4(OH)4, a hydrolysis product of Sn(NMe2)2, is transformed to tin (II) or tin (IV) oxide by solid and solution phase processing. Tin (II) oxide is formed by heating Sn6O4(OH)4 at ≤200 °C in air or under inert atmosphere. Tin (IV) oxide

  13. Development a solid state sensor based on SnO_2 nanoparticles for underground coal mine methane detection using zeolites as filter

    International Nuclear Information System (INIS)

    Abruzzi, R.C.; Dedavid, B.A.; Pires, M.J.R.; Luvizon, N.S.

    2016-01-01

    Aiming the monitoring of methane (CH_4) in underground coal mines, the tin oxide (SnO_2) was synthesis and applied to the development of a MOS sensor (metal oxide semiconductor). Zeolite have been tested as a filter of carbon dioxide (CO_2) to ensure the selectivity in the detection of CH_4. Analysis of Transmission Electron Microscopy (TEM) and X-Ray Diffraction (XRD) indicated a synthesis of nanoscaled structures. The energy band gap showed characteristic values for a potential application of SnO_2 in CH_4 sensors. Analysis of surface area by BET isotherms showed high values for the zeolite 13X and Y, while adsorption tests indicated that the zeolite 13X presents greater adsorption efficiency of CO_2. The sputtering technique for deposition of the electrodes, as well as the method of drop coating for deposition of SnO_2, proved effective in developing the sensor. (author)

  14. Effect of passive film on electrochemical surface treatment for indium tin oxide

    International Nuclear Information System (INIS)

    Wu, Yung-Fu; Chen, Chi-Hao

    2013-01-01

    Highlights: ► Oxalic, tartaric, and citric acid baths accompanying with applied voltages were used to treat the ITO surface. ► We investigated the changes in ITO surfaces by examining the potentiodynamic behavior of ITO films. ► AFM analysis showed the formation of a passive layer could assist to planarize surface. ► XPS analysis indicated this passive layer was mainly composed of SnO 2. ► A better planarization was obtained by treating in 3.0 wt.% tartaric acid at 0.5 V due to weak complexation strength. - Abstract: Changes in indium tin oxide (ITO) film surface during electrochemical treatment in oxalic acid, tartaric acid, and citric acid were investigated. Controlling the voltage applied on ITO film allows the formation of a passive layer, effectively protecting the film surface. X-ray photoelectron spectrometry showed that the passive layer composition was predominantly SnO 2 in tartaric acid, while a composite of tin oxide and tin carboxylate in citric or oxalic acid. Even though the passive films on ITO surface generated in these organic acids, the indium or tin could complex with the organic acid anions, enhancing the dissolution of ITO films. The experimental results show that the interaction between the dissolution and passivation could assist to planarize the ITO surface. We found that the optimal treatment at 0.5 V in 3 wt.% tartaric acid could provide the ITO surface with root-mean-squared roughness less than 1.0 nm, due to the weak complexing characteristics of tartaric acid.

  15. A novel approach for the synthesis of SnO2 nanoparticles and its application as a catalyst in the reduction and photodegradation of organic compounds.

    Science.gov (United States)

    Bhattacharjee, Archita; Ahmaruzzaman, M; Sinha, Tanur

    2015-02-05

    Tin oxide (SnO2) nanoparticles of sizes ∼4.5, ∼10 and ∼30 nm were successfully synthesized by a simple chemical precipitation method using amino acid, glycine which acts as a complexing agent and surfactant, namely sodium dodecyl sulfate (SDS) as a stabilizing agent, at various calcination temperatures of 200, 400 and 600°C. This method resulted in the formation of spherical SnO2 nanoparticles and the size of the nanoparticles was found to be a factor of calcination temperature. The spherical SnO2 nanoparticles show a tetragonal rutile crystalline structure. A dramatic increase in band gap energy (3.8-4.21 eV) was observed with a decrease in grain size (30-4.5 nm) due to three dimensional quantum confinement effect shown by the synthesized SnO2 nanoparticles. SnO2 nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), selected area electron diffraction (SAED) and fourier transformed infrared spectroscopy (FT-IR). The optical properties were investigated using UV-visible spectroscopy. These SnO2 nanoparticles were employed as catalyst for the reduction of p-nitro phenol to p-amino phenol in aqueous medium for the first time. The synthesized SnO2 nanoparticles act as an efficient photocatalyst in the degradation of methyl violet 6B dye under direct sunlight. For the first time, methyl violet 6B dye was degraded by SnO2 nanoparticles under direct sunlight. Copyright © 2014 Elsevier B.V. All rights reserved.

  16. SnO2-Based Nanomaterials: Synthesis and Application in Lithium-Ion Batteries and Supercapacitors

    Directory of Open Access Journals (Sweden)

    Qinqin Zhao

    2015-01-01

    Full Text Available Tin dioxide (SnO2 is an important n-type wide-bandgap semiconductor, and SnO2-based nanostructures are presenting themselves as one of the most important classes due to their various tunable physicochemical properties. In this paper, we firstly outline the syntheses of phase-pure SnO2 hierarchical structures with different morphologies such as nanorods, nanosheets, and nanospheres, as well as their modifications by doping and compositing with other materials. Then, we reviewed the design of SnO2-based nanostructures with improved performance in the areas of lithium-ion batteries (LIBs and supercapacitors.

  17. Preparation and electrochemical characterization of size controlled SnO2-RuO2 composite powder for monolithic hybrid battery

    International Nuclear Information System (INIS)

    Jeon, Young-Ah; No, Kwang-Soo; Choi, Sun Hee; Ahn, Jae pyong; Yoon, Young Soo

    2004-01-01

    Tin oxide (SnO 2 ) powders with a particle size of ∼20 nm were synthesized by a gas condensation method. Ruthenium oxide was loaded by an incipient-wetness method, in which an aqueous solution of RuCl 3 was added to the manufactured SnO 2 powder in an amount that was just sufficient to wet completely the powder. And then, the resulting solution was obtained after freeze-drying to synthesis the smallest particle. The as-synthesized SnO 2 powder with 1.5 wt.% ruthenium oxide (RuO 2 ) exhibited well-developed facets and had a very uniform particle size. The first discharge capacity was lower than comparing to commercial powder because of forming the second phase, but showed good cyclability. A maximum specific electrode capacitance of ∼20 F/g and a maximum specific power of ∼80 W/kg were achieved by manufactured SnO 2 with 1.5 wt.% RuO 2 . This result indicated that the synthesized SnO 2 -RuO 2 composite powder of nano-size scale is candidate for use in fabricating monolithic hybrid batteries using suitable electrolyte as well

  18. Defect Engineering and Interface Phenomena in Tin Oxide

    KAUST Repository

    Albar, Arwa

    2017-04-05

    The advance in transparent electronics requires high-performance transparent conducting oxide materials. The microscopic properties of these materials are sensitive to the presence of defects and interfaces and thus fundamental understanding is required for materials engineering. In this thesis, first principles density functional theory is used to investigate the possibility of tuning the structural, electronic and magnetic properties of tin oxide by means of defects and interfaces. Our aim is to reveal unique properties and the parameters to control them as well as to explain the origin of unique phenomena in oxide materials. The stability of native defect in tin monoxide (SnO) under strain is investigated using formation energy calculations. We find that the conductivity (which is controlled by native defects) can be switched from p-type to either n-type or undoped semiconducting by means of applied pressure. We then target inducing magnetism in SnO by 3d transition metal doping. We propose that V doping is efficient to realize spin polarization at high temperature. We discuss different tin oxide interfaces. Metallic states are found to form at the SnO/SnO2 interface with electronic properties that depend on the interface terminations. The origin of these states is explained in terms of charge transfer caused by chemical bonding and band alignment. For the SnO/SnO2 heterostructure, we observe the formation of a two dimensional hole gas at the interface, which is surprising as it cannot be explained by the standard polar catastrophe model. Thus, we propose a charge density discontinuity model to explain our results. The model can be generalized to other polar-polar interfaces. Motivated by technological applications, the electronic and structural properties of the MgO (100)/SnO2 (110) interface are investigated. Depending on the interface termination, we observe the formation of a two dimensional electron gas or spin polarized hole gas. Aiming to identify further

  19. Zr-doped SnO2 thin films synthesized by spray pyrolysis technique for barrier layers in solar cells

    Science.gov (United States)

    Reddy, N. Nanda Kumar; Akkera, Harish Sharma; Sekhar, M. Chandra; Park, Si-Hyun

    2017-12-01

    In the present work, we investigated the effect of Zr doping (0-6 at%) on the structural, electrical, and optical properties of tin oxide (SnO2) thin films deposited onto glass substrates using a spray pyrolysis technique. The room-temperature X-ray diffraction pattern shows that all deposited films exhibit polycrystalline tetragonal structure. The pure SnO2 film is grown along a preferred (200) direction, whereas Zr-doped SnO2 (Zr:SnO2) films started growing along the (220) orientation along with a high intensity peak of (200). Scanning electron microscope (SEM) and atomic force microscope (AFM) images showed that the grains of the films are spherical in structure, and the grain size decreased with increasing of Zr concentration. The optical transmission spectra of deposited films as a function of wavelength confirm that the average optical transmittance is > 85% for Zr:SnO2 films. The value of the optical bandgap is significantly decreased from 3.94 to 3.68 eV with increasing Zr concentration. Furthermore, the electrical measurements found that the sheet resistance ( R sh) and resistivity ( ρ) values are decreased with increasing of Zr doping. The lowest values of R sh = 6.82 Ω and ρ = 0.4 × 10- 3 Ω cm are found in 6-at% Zr-doped SnO2 film. In addition, a good efficiency value of the figure of merit ( ɸ = 3.35 × 10- 3 Ω-1) is observed in 6-at% Zr-doped SnO2 film. These outstanding properties of Zr-doped SnO2 films make them useful for several optoelectronic device applications.

  20. Interplay between O2 and SnO2: oxygen ionosorption and spectroscopic evidence for adsorbed oxygen.

    Science.gov (United States)

    Gurlo, Alexander

    2006-10-13

    Tin dioxide is the most commonly used material in commercial gas sensors based on semiconducting metal oxides. Despite intensive efforts, the mechanism responsible for gas-sensing effects on SnO(2) is not fully understood. The key step is the understanding of the electronic response of SnO(2) in the presence of background oxygen. For a long time, oxygen interaction with SnO(2) has been treated within the framework of the "ionosorption theory". The adsorbed oxygen species have been regarded as free oxygen ions electrostatically stabilized on the surface (with no local chemical bond formation). A contradiction, however, arises when connecting this scenario to spectroscopic findings. Despite trying for a long time, there has not been any convincing spectroscopic evidence for "ionosorbed" oxygen species. Neither superoxide ions O(2)(-), nor charged atomic oxygen O,(-) nor peroxide ions O(2)(2-) have been observed on SnO(2) under the real working conditions of sensors. Moreover, several findings show that the superoxide ion does not undergo transformations into charged atomic oxygen at the surface, and represents a dead-end form of low-temperature oxygen adsorption on reduced metal oxide.

  1. Powder preparation technics for SnO2 with submycrometrics particles

    International Nuclear Information System (INIS)

    Hiratsuka, R.S.; Pulcinelli, S.H.; Santilli, C.V.; Masetto, S.R.

    1989-01-01

    Preparation of SnO 2 fine powders is a pointer research because of this application as gas detecting sensors. This work shows basicaly two powder preparation methods: i) from metalic tin oxidation with nitric acid, ii) from SnCl 4 hydrolysis in aquous solution of amonia hydroxides. It was analysed the concentration of nitric acid and the pH of precipitation influency of the structural and morphologic characteristics of the obtained powders. The materials were characterized by X-ray diffraction, infra-red spectroscopy and specific surface area [pt

  2. Band gap narrowing and fluorescence properties of nickel doped SnO2 nanoparticles

    International Nuclear Information System (INIS)

    Ahmed, Arham S.; Shafeeq, M. Muhamed; Singla, M.L.; Tabassum, Sartaj; Naqvi, Alim H.; Azam, Ameer

    2011-01-01

    Nickel-doped tin oxide nanoparticles (sub-5 nm size) with intense fluorescence emission behavior have been synthesized by sol-gel route. The structural and compositional analysis has been carried out by using XRD, TEM, FESEM and EDAX. The optical absorbance spectra indicate a band gap narrowing effect and it was found to increase with the increase in nickel concentration. The band gap narrowing at low dopant concentration ( 2 -SnO 2-x alloying effect and for higher doping it may be due to the formation of defect sub-bands below the conduction band.

  3. Synthesis, characterization and catalytic application of silica supported tin oxide nanoparticles for synthesis of 2,4,5-tri and 1,2,4,5-tetrasubstituted imidazoles under solvent-free conditions

    Directory of Open Access Journals (Sweden)

    Ashok V. Borhade

    2017-02-01

    Full Text Available Highly efficient and eco-friendly, one pot synthesis of 1,2,4,5-tetra substituted imidazoles and 2,4,5-trisubstituted imidazoles was reported under solvent free conditions using nanocrystalline silica supported tin oxide (SiO2:SnO2 as a catalyst with excellent yield. The present methodology offers several advantages such as mild reaction conditions, short reaction time, good yield, high purity of product, recyclable catalyst without a noticeable decrease in catalytic activity and can be used for large scale synthesis. The synthesized SiO2:SnO2 nanocrystalline catalyst was characterized by XRD, BET surface area and TEM techniques.

  4. Epitaxial Sb-doped SnO_2 and Sn-doped In_2O_3 transparent conducting oxide contacts on GaN-based light emitting diodes

    International Nuclear Information System (INIS)

    Tsai, Min-Ying; Bierwagen, Oliver; Speck, James S.

    2016-01-01

    We demonstrate the growth of epitaxial (100)-oriented, rutile Sb-doped SnO_2 (ATO) and (111)-oriented, cubic Sn-doped In_2O_3 (ITO) transparent conducting oxide (TCO) contacts on top of an InGaN/GaN(0001) light emitting diode (LED) by plasma-assisted molecular beam epitaxy (PAMBE). Both oxides form rotational domains. The in-plane epitaxial alignment of the two ITO(111) rotational domains to the GaN(0001) was: GaN [21-10]|| ITO_D_o_m_a_i_n_1[‐ 211]|| ITO_D_o_m_a_i_n_2[‐ 1‐12]. A growth temperature as low as 600 °C was necessary to realize a low contact resistance between ATO and the top p-GaN layer of the LED but resulted in non-optimal resistivity (3.4 × 10"− "3 Ω cm) of the ATO. The current–voltage characteristics of a processed LED, however, were comparable to that of a reference LED with a standard electron-beam evaporated ITO top contact. At short wavelengths, the optical absorption of ATO was lower than that of ITO, which is beneficial even for blue LEDs. Higher PAMBE growth temperatures resulted in lower resistive ATO but higher contact resistance to the GaN, likely by the formation of an insulating Ga_2O_3 interface layer. The ITO contact grown by PAMBE at 600 °C showed extremely low resistivity (10"−"4 Ω cm) and high crystalline and morphological quality. These proof-of-principle results may lead to the development of epitaxial TCO contacts with low resistivity, well-defined interfaces to the p-GaN to help minimize contact losses, and enable further epitaxy on top of the TCO. - Highlights: • Plasma-assisted molecular beam epitaxy of SnO_2:Sb (ATO) and In_2O_3:Sn (ITO) contacts • Working light emitting diodes processed with the ATO contact on the top p-GaN layer • Low growth temperature ensures low contact resistance (limiting interface reaction). • ITO showed significantly better structural and transport properties than ATO. • ATO showed higher optical transmission at short wavelengths than ITO.

  5. In Situ Synthesis of Tungsten-Doped SnO2 and Graphene Nanocomposites for High-Performance Anode Materials of Lithium-Ion Batteries.

    Science.gov (United States)

    Wang, Shuai; Shi, Liyi; Chen, Guorong; Ba, Chaoqun; Wang, Zhuyi; Zhu, Jiefang; Zhao, Yin; Zhang, Meihong; Yuan, Shuai

    2017-05-24

    The composite of tungsten-doped SnO 2 and reduced graphene oxide was synthesized through a simple one-pot hydrothermal method. According to the structural characterization of the composite, tungsten ions were doped in the unit cells of tin dioxide rather than simply attaching to the surface. Tungsten-doped SnO 2 was in situ grown on the surface of graphene sheet to form a three-dimensional conductive network that enhanced the electron transportation and lithium-ion diffusion effectively. The issues of SnO 2 agglomeration and volume expansion could be also avoided because the tungsten-doped SnO 2 nanoparticles were homogeneously distributed on a graphene sheet. As a result, the nanocomposite electrodes of tungsten-doped SnO 2 and reduced graphene oxide exhibited an excellent long-term cycling performance. The residual capacity was still as high as 1100 mA h g -1 at 0.1 A g -1 after 100 cycles. It still remained at 776 mA h g -1 after 2000 cycles at the current density of 1A g -1 .

  6. Structural, optical and gas sensing properties of screen-printed nanostructured Sr-doped SnO2 thick film sensor

    International Nuclear Information System (INIS)

    Shaikh, F.I.; Chikhale, L.P.; Patil, J.Y.; Rajgure, A.V.; Suryavanshi, S.S.; Mulla, I.S.

    2013-01-01

    The nanocrystalline materials of strontium doped tin oxide powders were synthesized by conventional co-precipitation method. Synthesized nanophase SnO 2 powders were used to fabricate thick films of pure and Sr-doped SnO 2 using screen-printing technology and investigated for their gas sensing properties towards LPG, ethanol, ammonia and acetone vapor. The crystal structure and phase of the sintered powders were characterized by X-ray diffractometer (XRD) and microstructure by scanning electron microscopy (SEM). All the doped and undoped SnO 2 compositions revealed single phase and solid solution formation. X-ray diffractometer (XRD) results indicated that well crystallized Sr-doped SnO 2 particles of size about 10 nm were obtained at sintering temperature 700℃. The optical properties viz. UV-Vis, FTIR and Raman were used to characterize various physico-chemical properties of samples. The reduction of grain size in metal oxide is a key factor to enhance the gas sensing properties. The doping of Sr in SnO 2 has reduced the grain size and improved the gas response. The results of gas sensing measurements showed that the thick films deposited on alumina substrates using screen-printing technique exhibited high gas response, quick response time and fast recovery time to acetone gas at a working temperature of 250℃. Further, the selectivity of sensor towards acetone with respect to other reducing gases (LPG, ethanol, ammonia) was studied. (author)

  7. Facile synthesis and optical property of SnO2 flower-like architectures

    International Nuclear Information System (INIS)

    Zhao Qingrui; Li Zhengquan; Wu Changzheng; Bai Xue; Xie Yi

    2006-01-01

    Two-dimensional (2D) hierarchical tin dioxide (SnO 2 ) flower-like architectures consisting of sheet-like nanoparticles have been successfully prepared by a simply mild hydrothermal method based on the reaction between tin foil, NaOH and KBrO 3 . The photoluminescence (PL) spectrum exhibit that the flower-like architectures of SnO 2 have strong PL emission, which suggest its possible applications in nanoscaled optoelectronic devices. The formation process of SnO 2 architectures is investigated and the corresponding mechanism is also proposed

  8. Gas Sensors Based on Tin Oxide Nanoparticles Synthesized from a Mini-Arc Plasma Source

    Directory of Open Access Journals (Sweden)

    Ganhua Lu

    2006-01-01

    Full Text Available Miniaturized gas sensors or electronic noses to rapidly detect and differentiate trace amount of chemical agents are extremely attractive. In this paper, we report on the fabrication and characterization of a functional tin oxide nanoparticle gas sensor. Tin oxide nanoparticles are first synthesized using a convenient and low-cost mini-arc plasma source. The nanoparticle size distribution is measured online using a scanning electrical mobility spectrometer (SEMS. The product nanoparticles are analyzed ex-situ by high resolution transmission electron microscopy (HRTEM for morphology and defects, energy dispersive X-ray (EDX spectroscopy for elemental composition, electron diffraction for crystal structure, and X-ray photoelectron spectroscopy (XPS for surface composition. Nonagglomerated rutile tin oxide (SnO2 nanoparticles as small as a few nm have been produced. Larger particles bear a core-shell structure with a metallic core and an oxide shell. The nanoparticles are then assembled onto an e-beam lithographically patterned interdigitated electrode using electrostatic force to fabricate the gas sensor. The nanoparticle sensor exhibits a fast response and a good sensitivity when exposed to 100 ppm ethanol vapor in air.

  9. Indium Tin Oxide thin film gas sensors for detection of ethanol vapours

    International Nuclear Information System (INIS)

    Vaishnav, V.S.; Patel, P.D.; Patel, N.G.

    2005-01-01

    Indium Tin Oxide (ITO: In 2 O 3 + 17% SnO 2 ) thin films grown on alumina substrate at 648 K temperatures using direct evaporation method with two gold pads deposited on the top for electrical contacts were exposed to ethanol vapours (200-2500 ppm). The operating temperature of the sensor was optimized. The sensitivity variation of films having different thickness was studied. The sensitivity of the films deposited on Si substrates was studied. The response of the film with MgO catalytic layer on sensitivity and selectivity was observed. A novel approach of depositing thin stimulating layer of various metals/oxides below the ITO film was tried and tested

  10. Physicochemical study of properties of complex oxides of the system Li2O-MoO3-SnO2

    International Nuclear Information System (INIS)

    Safonov, V.V.; Chaban, N.G.; Kuz'mina, N.P.; Vashman, A.A.; Petrov, K.I.

    1990-01-01

    By the method of differential thermal analysis using X-ray phase analysis in the Li 2 O-MoO 3 -SnO 2 system (Li 2 Sn(MoO 4 ) 3 -Sn(MoO 4 ) 2 cross section) formation of a new complex of the composition Li 2 Sn 3 (MoO 4 ) 7 incongruently melting at 480 deg C is ascertained. IR, Raman and NMR spectra of Li 4 SnMo 2 O 10 , Li 2 Sn(MoO 4 ) 3 and Li 2 Sn 3 (MoO 4 ) 7 complex oxides are presented. According to 7 Li NMR spectra of Li 4 SnMo 2 O 10 , Li 2 Sn(MoO 4 ) 3 and Li 2 Sn 3 (MoO 4 ) 7 complex are presented. According to 7 Li NMR spectra the value of the lithium diffusion increases in the series Li 4 SnMo 2 O 10 →Li 2 Sn(MoO 4 ) 3 →Li 2 Sn 3 (MoO 4 ) 7

  11. Fluorine-doped SnO2 nanoparticles anchored on reduced graphene oxide as a high-performance lithium ion battery anode

    Science.gov (United States)

    Cui, Dongming; Zheng, Zhong; Peng, Xue; Li, Teng; Sun, Tingting; Yuan, Liangjie

    2017-09-01

    The composite of fluorine-doped SnO2 anchored on reduced graphene oxide (F-SnO2/rGO) has been synthesized through a hydrothermal method. F-SnO2 particles with average size of 8 nm were uniformly anchored on the surfaces of rGO sheets and the resulting composite had a high loading of F-SnO2 (ca. 90%). Benefiting from the remarkably improved electrical conductivity and Li-ion diffusion in the electrode by F doping and rGO incorporation, the composite material exhibited high reversible capacity, excellent long-term cycling stability and superior rate capability. The electrode delivered a large reversible capacity of 1037 mAh g-1 after 150 cycles at 100 mA g-1 and high rate capacities of 860 and 770 mAh g-1 at 1 and 2 A g-1, respectively. Moreover, the electrode could maintain a high reversible capacities of 733 mAh g-1 even after 250 cycles at 500 mA g-1. The outstanding electrochemical performance of the as-synthesized composite make it a promising anode material for high-energy lithium ion batteries.

  12. Electrical and Gas Sensing Properties of SnO2 Thick Film Resistors Prepared by Screen-printing Method

    Directory of Open Access Journals (Sweden)

    R. Y. BORSE

    2008-10-01

    Full Text Available Thick films of tin-oxide (SnO2 were deposited on alumina substrates employing screen-printing technique. The films were dried and fired at 680 0C for 30 minutes. The variation of D.C. resistance of thick films was measured in air as well as in H2S gas atmosphere as a function of temperature. The SnO2 films exhibit semiconducting behaviour. The SnO2 thick films studied were also showing decrease in resistance with increase of concentration of H2S gas. The film resistors showed the highest sensitivity to H2S gas at 350 0C. The XRD studies of the thick film indicate the presence of different phases of SnO2. The elemental analysis was confirmed by EDX spectra. The surface morphological study of the films was analyzed by SEM. The microstructure of the films was porous resulting from loosely interconnected small crystallites. The parameters such as grain size, activation energy, sensitivity and response time were described.

  13. Chip-to-chip SnO2 nanowire network sensors for room temperature H2 detection

    Science.gov (United States)

    Köck, A.; Brunet, E.; Mutinati, G. C.; Maier, T.; Steinhauer, S.

    2012-06-01

    The employment of nanowires is a very powerful strategy to improve gas sensor performance. We demonstrate a gas sensor device, which is based on silicon chip-to-chip synthesis of ultralong tin oxide (SnO2) nanowires. The sensor device employs an interconnected SnO2 nanowire network configuration, which exhibits a huge surface-to-volume ratio and provides full access of the target gas to the nanowires. The chip-to-chip SnO2 nanowire device is able to detect a H2 concentration of only 20 ppm in synthetic air with ~ 60% relative humidity at room temperature. At an operating temperature of 300°C a concentration of 50 ppm H2 results in a sensitivity of 5%. At this elevated temperature the sensor shows a linear response in a concentration range between 10 ppm and 100 ppm H2. The SnO2-nanowire fabrication procedure based on spray pyrolysis and subsequent annealing is performed at atmospheric pressure, requires no vacuum and allows upscale of the substrate to a wafer size. 3D-integration with CMOS chips is proposed as viable way for practical realization of smart nanowire based gas sensor devices for the consumer market.

  14. Structural, Optical and Ethanol Sensing Properties of Dy-Doped SnO2 Nanoparticles

    Science.gov (United States)

    Shaikh, F. I.; Chikhale, L. P.; Nadargi, D. Y.; Mulla, I. S.; Suryavanshi, S. S.

    2018-04-01

    We report a facile co-precipitation synthesis of dysprosium (Dy3+) doped tin oxide (SnO2) thick films and their use as gas sensors. The doping percentage (Dy3+) was varied from 1 mol.% to 4 mol.% with the step of 1 mol.%. As-produced material with varying doping levels were sintered in air; and by using a screen printing technique, their thick films were developed. Prior to sensing performance investigations, the films were examined for structural, morphological and compositional properties using x-ray diffraction, a field emission scanning electron microscope, a transmission electron microscope, selected area electron diffraction, energy dispersive analysis by x-rays, Fourier transform infrared spectroscopy and Raman spectroscopic techniques. The structural analyses revealed formation of single phase nanocrystalline material with tetragonal rutile structure of SnO2. The morphological analyses confirmed the nanocrystalline porous morphology of as-developed material. Elemental analysis defined the composition of material in accordance with the doping concentration. The produced sensor material exhibited good response towards different reducing gases (acetone, ethanol, LPG, and ammonia) at different operating temperatures. The present study confirms that the Dy3+ doping in SnO2 enhances the response towards ethanol with reduction in operating temperature. Particularly, 3 mol.% Dy3+ doped sensor exhibited the highest response (˜ 92%) at an operating temperature of 300°C with better selectivity, fast response (˜ 13 s) and recovery (˜ 22 s) towards ethanol.

  15. Resistividade do filme depositado via sol-gel e estado de oxidação do dopante Ce na matriz SnO2 Resistivity of the film deposited via sol-gel and oxidation state of Ce doping in SnO2 matrix

    Directory of Open Access Journals (Sweden)

    L. V. A. Scalvi

    2011-06-01

    Full Text Available Incorporação de Ce3+ ou Ce4+ em filmes finos de SnO2 depositados via sol-gel-dip-coating aumenta drasticamente a resistividade elétrica. No primeiro caso, temos comportamento aceitador do dopante, levando a matriz à alta compensação de carga. Por outro lado, para Ce4+, verifica-se aumento na largura da região de depleção do contorno de grão, resultando em maior espalhamento de elétrons. Medidas de caracterização elétrica sob pressão ambiente levam à barreiras de potencial mais altas do que as medidas sob vácuo, devido a adsorção de oxigênio na superfície das partículas. A presença de Ce3+ aumenta a transmitância no infravermelho, o que significa menor quantidade de elétrons livres. Dados de XANES confirmam que o tratamento térmico a 550 ºC dos filmes, ainda que promova oxidação parcial para Ce4+, preserva uma quantidade significativa (em torno de 60% no estado Ce3+. Espectroscopia Raman mostra a evolução dos modos de vibração intra-grãos de SnO2 com o aumento da temperatura de tratamento térmico.Incorporation of Ce3+ or Ce4+ in sol-gel dip-coating SnO2 thin films increases drastically its electrical resistivity. In the first case, it is due the acceptor-like nature of the doping ion, leading the matrix to high charge compensation. On the other hand, for Ce+4 doped samples, it is verified a broadening of the grain boundary depletion layer. Measurements under room pressure leads to higher intergrain potential barriers when compared to measurements carried out under vacuum conditions, due to oxygen adsorption at particles surface. The presence of Ce3+ increases the infrared transmittance, which means a lower free electron concentration. XANES data confirms that the thermal annealing at 550 ºC of thin films, although promotes oxidation to Ce4+, still keeps a significantly amount (about 60% of ions in the oxidation state Ce3+. Raman spectroscopy data show the evolution of the SnO2 bulk vibration modes with

  16. One-Pot Hybrid SnO2 /Poly(methyl methacrylate) Nanocomposite Formation through Pulsed Laser Irradiation.

    Science.gov (United States)

    Caputo, Gianvito; Scarpellini, Alice; Palazon, Francisco; Athanassiou, Athanassia; Fragouli, Despina

    2017-06-20

    The localized in situ formation of tin dioxide (SnO 2 ) nanoparticles embedded in poly(methyl methacrylate) (PMMA) films is presented. This is achieved by the photoinduced conversion of the tin acetate precursor included in polymeric films, through controlled UV or visible pulsed laser irradiation at λ=355 and 532 nm, respectively. The evolution of the formation of nanoparticles is followed by UV/Vis spectroscopy and shows that their growth is affected in different ways by the laser pulses at the two applied wavelengths. This, in combination with electron microscopy analysis, reveals that, depending on the irradiation wavelength, the size of the nanoparticles in the final nanocomposites differs. This difference is attributed to distinct mechanistic pathways that lead to the synthesis of small nanoparticles (from 1.5 to 4.5 nm) at λ=355 nm, whereas bigger ones (from 5 to 16 nm) are formed at λ=532 nm. At the same time, structural studies with both X-ray and electron diffraction measurements demonstrate the crystallinity of SnO 2 nanoparticles in both cases, whereas XPS analysis confirms the light-induced oxidation of tin acetate into SnO 2 . Taken all together, it is demonstrated that the pulsed laser irradiation at λ=355 and 532 nm leads to the formation of SnO 2 nanoparticles with defined features highly dispersed in PMMA solid matrices. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  17. Tin Dioxide Electrolyte-Gated Transistors Working in Depletion and Enhancement Modes.

    Science.gov (United States)

    Valitova, Irina; Natile, Marta Maria; Soavi, Francesca; Santato, Clara; Cicoira, Fabio

    2017-10-25

    Metal oxide semiconductors are interesting for next-generation flexible and transparent electronics because of their performance and reliability. Tin dioxide (SnO 2 ) is a very promising material that has already found applications in sensing, photovoltaics, optoelectronics, and batteries. In this work, we report on electrolyte-gated, solution-processed polycrystalline SnO 2 transistors on both rigid and flexible substrates. For the transistor channel, we used both unpatterned and patterned SnO 2 films. Since decreasing the SnO 2  area in contact with the electrolyte increases the charge-carrier density, patterned transistors operate in the depletion mode, whereas unpatterned ones operate in the enhancement mode. We also fabricated flexible SnO 2 transistors that operate in the enhancement mode that can withstand moderate mechanical bending.

  18. Synthesis of ultra-fine porous tin oxide fibres and its process characterization

    International Nuclear Information System (INIS)

    Wang Yu; Ramos, Idalia; Santiago-Aviles, Jorge J

    2007-01-01

    Porous rutile-structured SnO 2 fibres, with their length of several millimetres, diameter from 100 nm to 40 μm and potentials for sensor applications, were synthesized from a precursor solution of poly(ethylene oxide) (PEO), chloroform (CHCl 3 ) and dimethyldineodecanoate tin (C 22 H 44 O 4 Sn) using electrospinning and metal-organic decomposition techniques. Fourier-transform infrared spectroscopy, thermogravimetric and differential thermal analysis and x-ray diffraction were used to characterize the synthesized fibres so as to reveal the series of physical and chemical changes occurring from the starting chemicals to the final product of ultra-fine SnO 2 fibres: the solvent CHCl 3 evaporates during the electrospinning; the organic groups in PEO and C 22 H 44 O 4 Sn decompose, with Sn-C bond in C 22 H 44 O 4 Sn replaced by Sn-O between 220 and 300 deg. C, and the atomic arrangement transforms into the genesis of a rutile-type lattice between 300 and 380 deg. C; the incipient lattice finally develops into the rutile structure during heat treatment at higher temperatures up to 600 deg. C

  19. Facile synthesis of antimony-doped tin oxide nanoparticles by a polymer-pyrolysis method

    International Nuclear Information System (INIS)

    Li, Yuan-Qing; Wang, Jian-Lei; Fu, Shao-Yun; Mei, Shi-Gang; Zhang, Jian-Min; Yong, Kang

    2010-01-01

    In this article, antimony-doped tin oxide (ATO) nanoparticles was synthesized by a facile polymer-pyrolysis method. The pyrolysis behaviors of the polymer precursors prepared via in situ polymerization of metal salts and acrylic acid were analyzed by simultaneous thermogravimetric and differential scanning calorimetry (TG-DSC). The structural and morphological characteristics of the products were studied by powder X-ray diffraction (XRD) and transmission electron microscope (TEM). The results reveal that the ATO nanoparticles calcined at 600 o C show good crystallinity with the cassiterite structure and cubic-spherical like morphology. The average particle size of ATO decreases from 200 to 15 nm as the Sb doping content increases from 5 mol% to 15 mol%. Electrical resistivity measurement shows that the resistivity for the 10-13 mol% Sb-doped SnO 2 nanoparticles is reduced by more than three orders compared with the pure SnO 2 nanoparticles. In addition, due to its versatility this polymer-pyrolysis method can be extended to facile synthesis of other doped n-type semiconductor, such as In, Ga, Al doped ZnO, Sn doped In 2 O 3 .

  20. Spark Plasma Sintering and Densification Mechanisms of Antimony-Doped Tin Oxide Nanoceramics

    Directory of Open Access Journals (Sweden)

    Junyan Wu

    2013-01-01

    Full Text Available Densification of antimony-doped tin oxide (ATO ceramics without sintering aids is very difficult, due to the volatilization of SnO2, formation of deleterious phases above 1000°C, and poor sintering ability of ATO particles. In this paper, monodispersed ATO nanoparticles were synthesized via sol-gel method, and then ATO nanoceramics with high density were prepared by spark plasma sintering (SPS technology using the as-synthesized ATO nanoparticles without the addition of sintering aids. The effect of Sb doping content on the densification was investigated, and the densification mechanisms were explored. The results suggest that ATO nanoparticles derived from sol-gel method show good crystallinity with a crystal size of 5–20 nm and Sb is incorporated into the SnO2 crystal structure. When the SPS sintering temperature is 1000°C and the Sb doping content is 5 at.%, the density of ATO nanoceramics reaches a maximum value of 99.2%. Densification mechanisms are explored in detail.

  1. Label-free SnO2 nanowire FET biosensor for protein detection

    Science.gov (United States)

    Jakob, Markus H.; Dong, Bo; Gutsch, Sebastian; Chatelle, Claire; Krishnaraja, Abinaya; Weber, Wilfried; Zacharias, Margit

    2017-06-01

    Novel tin oxide field-effect-transistors (SnO2 NW-FET) for pH and protein detection applicable in the healthcare sector are reported. With a SnO2 NW-FET the proof-of-concept of a bio-sensing device is demonstrated using the carrier transport control of the FET channel by a (bio-) liquid modulated gate. Ultra-thin Al2O3 fabricated by a low temperature atomic layer deposition (ALD) process represents a sensitive layer to H+ ions safeguarding the nanowire at the same time. Successful pH sensitivity is demonstrated for pH ranging from 3 to 10. For protein detection, the SnO2 NW-FET is functionalized with a receptor molecule which specifically interacts with the protein of interest to be detected. The feasibility of this approach is demonstrated via the detection of a biotinylated protein using a NW-FET functionalized with streptavidin. An immediate label-free electronic read-out of the signal is shown. The well-established Enzyme-Linked Immunosorbent Assay (ELISA) method is used to determine the optimal experimental procedure which would enable molecular binding events to occur while being compatible with a final label-free electronic read-out on a NW-FET. Integration of the bottom-up fabricated SnO2 NW-FET pH- and biosensor into a microfluidic system (lab-on-a-chip) allows the automated analysis of small volumes in the 400 μl range as would be desired in portable on-site point-of-care (POC) devices for medical diagnosis.

  2. Calcium carbonate electronic-insulating layers improve the charge collection efficiency of tin oxide photoelectrodes in dye-sensitized solar cells

    International Nuclear Information System (INIS)

    Shaikh, Shoyebmohamad F.; Mane, Rajaram S.; Hwang, Yun Jeong; Joo, Oh-Shim

    2015-01-01

    In dye-sensitized solar cells (DSSCs), a surface passivation layer has been employed on the tin oxide (SnO 2 ) photoanodes to enhance the charge collection efficiency, and thus the power conversion efficiency. Herein, we demonstrate that the electronic-insulating layering of calcium carbonate (CaCO 3 ) can improve the charge collection efficiency in dye-sensitized solar cells designed with photoanodes. In order to evaluate the effectiveness of CaCO 3 layering, both layered and pristine SnO 2 photoanodes are characterized with regard to their structures, morphologies, and photo-electrochemical measurements. The SnO 2 -6L CaCO 3 photoanode has demonstrated as high as 3.5% power conversion efficiency; 3.5-fold greater than that of the pristine SnO 2 photoanode. The enhancement in the power conversion efficiency is corroborated with the number of the dye molecules, the passivation of surface states, a negative shift in the conduction band position, and the reduced electron recombination rate of photoelectrons following the coating of the CaCO 3 surface layer

  3. Electrical and Optical Properties of Fluorine Doped Tin Oxide Thin Films Prepared by Magnetron Sputtering

    Directory of Open Access Journals (Sweden)

    Ziad Y. Banyamin

    2014-10-01

    Full Text Available Fluorine doped tin oxide (FTO coatings have been prepared using the mid-frequency pulsed DC closed field unbalanced magnetron sputtering technique in an Ar/O2 atmosphere using blends of tin oxide and tin fluoride powder formed into targets. FTO coatings were deposited with a thickness of 400 nm on glass substrates. No post-deposition annealing treatments were carried out. The effects of the chemical composition on the structural (phase, grain size, optical (transmission, optical band-gap and electrical (resistivity, charge carrier, mobility properties of the thin films were investigated. Depositing FTO by magnetron sputtering is an environmentally friendly technique and the use of loosely packed blended powder targets gives an efficient means of screening candidate compositions, which also provides a low cost operation. The best film characteristics were achieved using a mass ratio of 12% SnF2 to 88% SnO2 in the target. The thin film produced was polycrystalline with a tetragonal crystal structure. The optimized conditions resulted in a thin film with average visible transmittance of 83% and optical band-gap of 3.80 eV, resistivity of 6.71 × 10−3 Ω·cm, a carrier concentration (Nd of 1.46 × 1020 cm−3 and a mobility of 15 cm2/Vs.

  4. Structural and optical studies of 100 MeV Au irradiated thin films of tin oxide

    Science.gov (United States)

    Jaiswal, Manoj Kumar; Kanjilal, D.; Kumar, Rajesh

    2013-11-01

    Thin films of tin(IV) oxide (SnO2) of 100 nm thickness were grown on silicon (1 0 0) matrices by electron beam evaporation deposition technique under high vacuum. The thicknesses of these films were monitored by piezo-sensor attached to the deposition chamber. Nanocrystallinity is achieved in these thin films by 100 MeV Au8+ using 1 pnA current at normal incidence with ion fluences varying from 1 × 1011 ions/cm2 to 5 × 1013 ions/cm2. Swift Heavy Ion beam irradiation was carried out by using 15 UD Pelletron Accelerator at IUAC, New Delhi, India. Optical studies of pristine and ion irradiated thin films were characterized by UV-Visible spectroscopy and Fourier Transform Infrared (FTIR) spectroscopy. Prominent peak at 610 cm-1 in FTIR spectrum confirmed the O-Sn-O bonding of tin(IV) oxide. For Surface topographical studies and grain size calculations, these films were characterized by Atomic Force Microscope (AFM) using Nanoscope III-A. Crystallinity and phase transformation due to irradiation of pristine and irradiated films were characterized by Glancing Angle X-ray Diffraction (GAXRD) using Brucker-D8 advance model. GAXRD results show improvement in crystallinity and phase transformation due to swift heavy ion irradiation. Grain size distribution was verified by AFM and GAXRD results. Swift heavy ion induced modifications in thin films of SnO2 were confirmed by the presence of prominent peaks at 2θ values of 30.65°, 32.045°, 43.94°, 44.96° and 52.36° in GAXRD spectrum.

  5. Tin dioxide nanoparticles impregnated in graphite oxide for improved lithium storage and cyclability in secondary ion batteries

    International Nuclear Information System (INIS)

    Lee, Bichna; Han, Su Chul; Oh, Minhak; Lah, Myoung Soo; Sohn, Kee-Sun; Pyo, Myoungho

    2013-01-01

    SnO 2 /graphene nanocomposites were prepared from graphite oxide (GTO). Sn 2+ precursors were impregnated between graphene layers of GTO and subsequently subjected to thermal treatment to produce nanocomposites consisting of SnO 2 and reduced GTO (SnO 2 /rGTO). When thermally reduced, the pre-aligned nature of graphene layers in GTO produced densely packed and thick graphene stacks, in contrast to graphene layers in the SnO 2 nanocomposites (SnO 2 /rGO) made from thermal reduction of mechanically exfoliated graphene oxide (GO). The surface area and void volume of the SnO 2 /rGTO nanocomposites (280 m 2 g −1 and 0.27 cm 3 g −1 , respectively) were significantly decreased, by comparison with those of the SnO 2 /rGO nanocomposites (390 m 2 g −1 and 0.39 cm 3 g −1 , respectively), which resulted in an enhanced dimensional-stability of SnO 2 during the lithium alloying/dealloying processes. As a result, SnO 2 /rGTO proved to be superior to SnO 2 /rGO as an anode material in lithium ion batteries from the view-point of both reversible charge–discharge (C–D) capacity and cyclability. The simplification of the nanocomposite preparation process (the removal of mechanical exfoliation) is an additional benefit of using GTO as a template

  6. Inorganic ion exchanger based on tin/titanium mixed oxide doped with europium to be used in radioactive waste

    International Nuclear Information System (INIS)

    Paganini, Paula P.; Felinto, Maria Claudia F.C.; Kodaira, Claudia A.; Brito, Hermi F.

    2009-01-01

    This work presents the results of synthesis and characterization of an inorganic ion exchanger based on tin/titanium mixed oxides doped with europium (SnO 2 /TiO 2 :Eu 3+ ) to be used in environmental field. The adsorption study of nickel was realized in this exchanger to recover the nickel metal which is in thorium-nickel alloys used as electrode of discharge lamps. The studied exchanger was synthesized by neutralization of tin chloride (IV) and titanium chloride (III) mixed solution and characterized by thermogravimetric measurement (TG), Differential Scanning Calorimetry (DSC), X-Ray Powder Diffraction (XRD), Infrared Spectroscopy (IR) and Scanning Electron Microscopy (SEM). The adsorption study showed that these inorganic ion exchangers are good materials to recovery nickel with high weight distribution ratios (Dw Ni 2+ ) and percent adsorption. (author)

  7. Preparation of n-type semiconductor SnO2 thin films

    International Nuclear Information System (INIS)

    Rahal, Achour; Benramache, Said; Benhaoua, Boubaker

    2013-01-01

    We studied fluorine-doped tin oxide on a glass substrate at 350°C using an ultrasonic spray technique. Tin (II) chloride dehydrate, ammonium fluoride dehydrate, ethanol and NaOH were used as the starting material, dopant source, solvent and stabilizer, respectively. The SnO 2 : F thin films were deposited at 350°C and a pending time of 60 and 90 s. The as-grown films exhibit a hexagonal wurtzite structure and have (101) orientation. The G = 31.82 nm value of the grain size is attained from SnO 2 : F film grown at 90 s, and the transmittance is greater than 80% in the visible region. The optical gap energy is found to measure 4.05 eV for the film prepared at 90 s, and the increase in the electrical conductivity of the film with the temperature of the sample is up to a maximum value of 265.58 (Ω·cm) −1 , with the maximum activation energy value of the films being found to measure 22.85 meV, indicating that the films exhibit an n-type semiconducting nature. (semiconductor materials)

  8. SnO2-Based Nanomaterials: Synthesis and Application in Lithium-Ion Batteries and Supercapacitors

    OpenAIRE

    Zhao, Qinqin; Ma, Lisha; Zhang, Qiang; Wang, Chenggang; Xu, Xijin

    2015-01-01

    Tin dioxide (SnO2) is an important n-type wide-bandgap semiconductor, and SnO2-based nanostructures are presenting themselves as one of the most important classes due to their various tunable physicochemical properties. In this paper, we firstly outline the syntheses of phase-pure SnO2 hierarchical structures with different morphologies such as nanorods, nanosheets, and nanospheres, as well as their modifications by doping and compositing with other materials. Then, we reviewed the design of ...

  9. Preparation and Characterization of Tin Oxide Nanowires

    Directory of Open Access Journals (Sweden)

    A. Kabiri

    2013-12-01

    Full Text Available The aim of this research is preparation of SnO2 nanowires by means of Thermal chemical reaction vapor transport deposition (TCRVTD method from SnO powders. The morphology, chemical composition and microstructure properties of the nanowires are characterized using field emission scanning electron microscope (FE-SEM, EDS, and XRD. The XRD diffraction patterns reveal that the SnO2 nanowires have been grown in the form of tetragonal crystal structures with the lattice parameter of a=b=0.440 nm, and c=0.370 nm. The SEM images reveal that SnO2 nanowires have successfully been grown on the Si substrate. The EDS patterns show that only elements of Sn, O and Au are detected. Prior to the VLS process the substrate is coated by a thin layer of Au. The diameter of nanowires is measured to be something between 20-100 nm.

  10. Fabrication of textured SnO2 transparent conductive films using self-assembled Sn nanospheres

    Science.gov (United States)

    Fukumoto, Michitaka; Nakao, Shoichiro; Hirose, Yasushi; Hasegawa, Tetsuya

    2018-06-01

    We present a novel method to fabricate textured surfaces on transparent conductive SnO2 films by processing substrates through a bottom-up technique with potential for industrially scalable production. The substrate processing consists of three steps: deposition of precursor Sn films on glass substrates, formation of a self-assembled Sn nanosphere layer with reductive annealing, and conversion of Sn to SnO2 by oxidative annealing. Ta-doped SnO2 films conformally deposited on the self-assembled nanospherical SnO2 templates exhibited attractive optical and electrical properties, namely, enhanced haze values and low sheet resistances, for applications as transparent electrodes in photovoltaics.

  11. Morphological and humidity sensing characteristics of SnO 2 –CuO ...

    Indian Academy of Sciences (India)

    This paper reports the synthesis of SnO2–CuO, SnO2–Fe2O3 and SnO2–SbO2 composites of nano oxides and comparative study of humidity sensing on their electrical resistances. CuO, Fe2O3 and SbO2 were added within base material SnO2 in the ratio 1 : 0.25, 1 : 0.50 and 1 : 1. Characterizations of materials were done ...

  12. Three-dimensional mesoporous graphene aerogel-supported SnO2 nanocrystals for high-performance NO2 gas sensing at low temperature.

    Science.gov (United States)

    Li, Lei; He, Shuijian; Liu, Minmin; Zhang, Chunmei; Chen, Wei

    2015-02-03

    A facile and cost-efficient hydrothermal and lyophilization two-step strategy has been developed to prepare three-dimensional (3D) SnO2/rGO composites as NO2 gas sensor. In the present study, two different metal salt precursors (Sn(2+) and Sn(4+)) were used to prepare the 3D porous composites. It was found that the products prepared from different tin salts exhibited different sensing performance for NO2 detection. The scanning electron microscopy and transmission electron microscopy characterizations clearly show the macroporous 3D hybrids, nanoporous structure of reduce graphene oxide (rGO), and the supported SnO2 nanocrystals with an average size of 2-7 nm. The specific surface area and porosity properties of the 3D mesoporous composites were analyzed by Braunauer-Emmett-Teller method. The results showed that the SnO2/rGO composite synthesized from Sn(4+) precursor (SnO2/rGO-4) has large surface area (441.9 m(2)/g), which is beneficial for its application as a gas sensing material. The gas sensing platform fabricated from the SnO2/rGO-4 composite exhibited a good linearity for NO2 detection, and the limit of detection was calculated to be as low as about 2 ppm at low temperature. The present work demonstrates that the 3D mesoporous SnO2/rGO composites with extremely large surface area and stable nanostructure are excellent candidate materials for gas sensing.

  13. Modification of SnO2 Anodes by Atomic Layer Deposition for High Performance Lithium Ion Batteries

    KAUST Repository

    Yesibolati, Nulati

    2013-01-01

    Tin dioxide (SnO2) is considered one of the most promising anode materials for Lithium ion batteries (LIBs), due to its large theoretical capacity and natural abundance. However, its low electronic/ionic conductivities, large volume change during

  14. Structural studies of supported tin catalysts

    Science.gov (United States)

    Nava, Noel; Viveros, Tomás

    1999-11-01

    Tin oxide was supported on aluminium oxide, titanium oxide, magnesium oxide and silicon oxide, and the resulting interactions between the components in the prepared samples and after reduction were characterized by Mössbauer spectroscopy. It was observed that in the oxide state, tin is present as SnO2 on alumina, magnesia and silica, but on titania tin occupies Ti sites in the structure. After hydrogen treatment at high temperatures, tin is reduced from Sn(4) to Sn(2) on alumina and titania; it is reduced from Sn(4) to Sn(0) on silica, and is practically not reduced on magnesia. These results reveal the degree of interaction between tin and the different supports studied.

  15. Structural studies of supported tin catalysts

    International Nuclear Information System (INIS)

    Nava, Noel; Viveros, Tomas

    1999-01-01

    Tin oxide was supported on aluminium oxide, titanium oxide, magnesium oxide and silicon oxide, and the resulting interactions between the components in the prepared samples and after reduction were characterized by Moessbauer spectroscopy. It was observed that in the oxide state, tin is present as SnO 2 on alumina, magnesia and silica, but on titania tin occupies Ti sites in the structure. After hydrogen treatment at high temperatures, tin is reduced from Sn(4) to Sn(2) on alumina and titania; it is reduced from Sn(4) to Sn(0) on silica, and is practically not reduced on magnesia. These results reveal the degree of interaction between tin and the different supports studied

  16. The selective catalytic reduction of NO with NH3 over a novel Ce-Sn-Ti mixed oxides catalyst: Promotional effect of SnO2

    Science.gov (United States)

    Yu, Ming'e.; Li, Caiting; Zeng, Guangming; Zhou, Yang; Zhang, Xunan; Xie, Yin'e.

    2015-07-01

    A series of novel catalysts (CexSny) for the selective catalytic reduction of NO by NH3 were prepared by the inverse co-precipitation method. The aim of this novel design was to improve the NO removal efficiency of CeTi by the introduction of SnO2. It was found that the Ce-Sn-Ti catalyst was much more active than Ce-Ti and the best Ce:Sn molar ratio was 2:1. Ce2Sn1 possessed a satisfied NO removal efficiency at low temperature (160-280 °C), while over 90% NO removal efficiency maintained in the temperature range of 280-400 °C at the gas hourly space velocity (GHSV) of 50,000 h-1. Besides, Ce2Sn1 kept a stable NO removal efficiency within a wide range of GHSV and a long period of reacting time. Meanwhile, Ce2Sn1 exhibited remarkable resistance to both respectively and simultaneously H2O and SO2 poisoning due to the introduction of SnO2. The promotional effect of SnO2 was studied by N2 adsorption-desorption, X-ray diffraction (XRD), Raman spectra, X-ray photoelectron spectroscopy (XPS) and H2 temperature programmed reduction (H2-TPR) for detail information. The characterization results revealed that the excellent catalytic performance of Ce2Sn1 was associated with the higher specific surface area, larger pore volume and poorer crystallization. Besides, the introduction of SnO2 could result in not only greater conversion of Ce4+ to Ce3+ but also the increase amount of chemisorbed oxygen, which are beneficial to improve the SCR activity. More importantly, a novel peak appearing at lower temperatures through the new redox equilibrium of 2Ce4+ + Sn2+ ↔ 2Ce3+ + Sn4+ and higher total H2 consumption can be obtained by the addition of SnO2. Finally, the possible reaction mechanism of the selective catalytic reduction over Ce2Sn1 was also proposed.

  17. The electrical, optical, structural and thermoelectrical characterization of n- and p-type cobalt-doped SnO 2 transparent semiconducting films prepared by spray pyrolysis technique

    Science.gov (United States)

    Bagheri-Mohagheghi, Mohammad-Mehdi; Shokooh-Saremi, Mehrdad

    2010-10-01

    The electrical, optical and structural properties of Cobalt (Co) doped SnO 2 transparent semiconducting thin films, deposited by the spray pyrolysis technique, have been studied. The SnO 2:Co films, with different Co-content, were deposited on glass substrates using an aqueous-ethanol solution consisting of tin and cobalt chlorides. X-ray diffraction studies showed that the SnO 2:Co films were polycrystalline only with tin oxide phases and preferential orientations along (1 1 0) and (2 1 1) planes and grain sizes in the range 19-82 nm. Optical transmittance spectra of the films showed high transparency ∼75-90% in the visible region, decreasing with increase in Co-doping. The optical absorption edge for undoped SnO 2 films was found to be 3.76 eV, while for higher Co-doped films shifted toward higher energies (shorter wavelengths) in the range 3.76-4.04 eV and then slowly decreased again to 4.03 eV. A change in sign of the Hall voltage and Seebeck coefficient was observed for a specific acceptor dopant level ∼11.4 at% in film and interpreted as a conversion from n-type to p-type conductivity. The thermoelectric electro-motive force (e.m.f.) of the films was measured in the temperature range 300-500 K and Seebeck coefficients were found in the range from -62 to +499 μVK -1 for various Co-doped SnO 2 films.

  18. The electrical, optical, structural and thermoelectrical characterization of n- and p-type cobalt-doped SnO2 transparent semiconducting films prepared by spray pyrolysis technique

    International Nuclear Information System (INIS)

    Bagheri-Mohagheghi, Mohammad-Mehdi; Shokooh-Saremi, Mehrdad

    2010-01-01

    The electrical, optical and structural properties of Cobalt (Co) doped SnO 2 transparent semiconducting thin films, deposited by the spray pyrolysis technique, have been studied. The SnO 2 :Co films, with different Co-content, were deposited on glass substrates using an aqueous-ethanol solution consisting of tin and cobalt chlorides. X-ray diffraction studies showed that the SnO 2 :Co films were polycrystalline only with tin oxide phases and preferential orientations along (1 1 0) and (2 1 1) planes and grain sizes in the range 19-82 nm. Optical transmittance spectra of the films showed high transparency ∼75-90% in the visible region, decreasing with increase in Co-doping. The optical absorption edge for undoped SnO 2 films was found to be 3.76 eV, while for higher Co-doped films shifted toward higher energies (shorter wavelengths) in the range 3.76-4.04 eV and then slowly decreased again to 4.03 eV. A change in sign of the Hall voltage and Seebeck coefficient was observed for a specific acceptor dopant level ∼11.4 at% in film and interpreted as a conversion from n-type to p-type conductivity. The thermoelectric electro-motive force (e.m.f.) of the films was measured in the temperature range 300-500 K and Seebeck coefficients were found in the range from -62 to +499 μVK -1 for various Co-doped SnO 2 films.

  19. Atomic Layer Deposition of SnO2 on MXene for Li-Ion Battery Anodes

    KAUST Repository

    Ahmed, Bilal

    2017-02-24

    In this report, we show that oxide battery anodes can be grown on two-dimensional titanium carbide sheets (MXenes) by atomic layer deposition. Using this approach, we have fabricated a composite SnO2/MXene anode for Li-ion battery applications. The SnO2/MXene anode exploits the high Li-ion capacity offered by SnO2, while maintaining the structural and mechanical integrity by the conductive MXene platform. The atomic layer deposition (ALD) conditions used to deposit SnO2 on MXene terminated with oxygen, fluorine, and hydroxyl-groups were found to be critical for preventing MXene degradation during ALD. We demonstrate that SnO2/MXene electrodes exhibit excellent electrochemical performance as Li-ion battery anodes, where conductive MXene sheets act to buffer the volume changes associated with lithiation and delithiation of SnO2. The cyclic performance of the anodes is further improved by depositing a very thin passivation layer of HfO2, in the same ALD reactor, on the SnO2/MXene anode. This is shown by high-resolution transmission electron microscopy to also improve the structural integrity of SnO2 anode during cycling. The HfO2 coated SnO2/MXene electrodes demonstrate a stable specific capacity of 843 mAh/g when used as Li-ion battery anodes.

  20. Use of a Phage-Display Method to Identify Peptides that Bind to a Tin Oxide Nanosheets.

    Science.gov (United States)

    Nakazawa, Hikaru; Seta, Yasuko; Hirose, Tatsuya; Masuda, Yoshitake; Umetsu, Mitsuo

    2018-01-01

    Nanosheets of SnO2 which an n-type semiconductor with a rutile-type crystalline structure are predominantly used as gas sensors. SnO2 nanosheets have a tetragonal crystal structure where growth along the c-axis is suppressed to form a sheet. The major exposed facets of SnO2 nanosheets have {110}, {101} and {211} crystal planes along the a-axis, with the reduced {110} surface having a particularly high surface energy. Identifying peptides that bind to specific crystal planes by using peptide phage-display approach will increase the potential applications of metal oxide nanomaterials by fusing proteins with desirable active sites to peptides that adsorb at high density on the major exposed crystal plane of nanosheets. It may be possible to construct highly sensitive biosensors. The main objective of the present study is to identify peptides that adsorb preferentially to a SnO2 nanosheet by using peptide-phage display approach. Four milligrams of SnO2 nanosheet were mixed with 1011 plaque-forming units of Ph.D.-12 Phage Display Peptide Library. Phage-bound nanosheet particles were washed 10 times with 1 mL of phosphatebuffered saline containing 0.5% Tween 20. Phages bound to the nanosheet were eluted with three different buffers: (1) high-salt buffer containing 2 M NaCl (pH 7.5); (2) acidic buffer containing 200 mM Gly-HCl (pH 2.2); and (3) high-phosphate-ion buffer containing 500 mM NaH2PO4 (pH 7.5). The eluted phages were subjected to four or five rounds of biopanning. At each round, individual plaques were picked from the plates, and the amino acid sequences of the peptides were identified by DNA sequencing. The identified SnO2-binding peptides labeled with fluorescein isothiocyanate were synthesized. Adsorption isotherms were constructed at peptide concentrations ranging from 0.25 to 2.0 µM with 4mg of nanomaterials. We were determined the sequences of 11 clones with the high-salt buffer, 7 with the high-phosphateion buffers, and 6 with the acidic buffer and

  1. Gas Sensing Properties of Ordered Mesoporous SnO2

    Directory of Open Access Journals (Sweden)

    Michael Tiemann

    2006-04-01

    Full Text Available We report on the synthesis and CO gas-sensing properties of mesoporoustin(IV oxides (SnO2. For the synthesis cetyltrimethylammonium bromide (CTABr wasused as a structure-directing agent; the resulting SnO2 powders were applied as films tocommercially available sensor substrates by drop coating. Nitrogen physisorption showsspecific surface areas up to 160 m2·g-1 and mean pore diameters of about 4 nm, as verifiedby TEM. The film conductance was measured in dependence on the CO concentration inhumid synthetic air at a constant temperature of 300 °C. The sensors show a high sensitivityat low CO concentrations and turn out to be largely insensitive towards changes in therelative humidity. We compare the materials with commercially available SnO2-basedsensors.

  2. SnO2 nanosheets grown on graphene sheets with enhanced lithium storage properties.

    Science.gov (United States)

    Ding, Shujiang; Luan, Deyan; Boey, Freddy Yin Chiang; Chen, Jun Song; Lou, Xiong Wen David

    2011-07-07

    We demonstrate a new hydrothermal method to directly grow SnO(2) nanosheets on a graphene oxide support that is subsequently reduced to graphene. This unique SnO(2)/graphene hybrid structure exhibits enhanced lithium storage properties with high reversible capacities and good cycling performance. This journal is © The Royal Society of Chemistry 2011

  3. Solvothermal-induced 3D macroscopic SnO2/nitrogen-doped graphene aerogels for high capacity and long-life lithium storage.

    Science.gov (United States)

    Wang, Ronghua; Xu, Chaohe; Sun, Jing; Gao, Lian; Yao, Heliang

    2014-03-12

    3D macroscopic tin oxide/nitrogen-doped graphene frameworks (SnO2/GN) were constructed by a novel solvothermal-induced self-assembly process, using SnO2 colloid as precursor (crystal size of 3-7 nm). Solvothermal treatment played a key role as N,N-dimethylmethanamide (DMF) acted both as reducing reagent and nitrogen source, requiring no additional nitrogen-containing precursors or post-treatment. The SnO2/GN exhibited a 3D hierarchical porous architecture with a large surface area (336 m(2)g(-1)), which not only effectively prevented the agglomeration of SnO2 but also facilitated fast ion and electron transport through 3D pathways. As a result, the optimized electrode with GN content of 44.23% exhibited superior rate capability (1126, 855, and 614 mAh g(-1) at 1000, 3000, and 6000 mA g(-1), respectively) and extraordinary prolonged cycling stability at high current densities (905 mAh g(-1) after 1000 cycles at 2000 mA g(-1)). Electrochemical impedance spectroscopy (EIS) and morphological study demonstrated the enhanced electrochemical reactivity and good structural stability of the electrode.

  4. Transfer of preheat-treated SnO 2 via a sacrificial bridge-type ZnO layer for ethanol gas sensor

    KAUST Repository

    Lee, Da Hoon; Kang, Sun Kil; Pak, Yusin; Lim, Namsoo; Lee, Ryeri; Kumaresan, Yogeenth; Lee, Sungeun; Lee, Chaedeok; Ham, Moon-Ho; Jung, Gun Young

    2017-01-01

    The progress in developing the microelectromechanical system (MEMS) heater-based SnO2 gas sensors was hindered by the subsequent heat treatment of the tin oxide (SnO2), nevertheless it is required to obtain excellent sensor characteristics. During the sintering process, the MEMS heater and the contact electrodes can be degraded at such a high temperature, which could reduce the sensor response and reliability. In this research, we presented a process of preheating the printed SnO2 sensing layer on top of a sacrificial bridge-type ZnO layer at such a high temperature, followed by transferring it onto the contact electrodes of sensor device by selective etching of the sacrificial ZnO layer. Therefore, the sensor device was not exposed to the high sintering temperature. The SnO2 gas sensor fabricated by the transfer process exhibited a rectangular sensing curve behavior with a rapid response of 52 s at 20 ppm ethanol concentration. In addition, reliable and repeatable sensing characteristics were obtained even at an ethanol gas concentration of 5 ppm.

  5. Transfer of preheat-treated SnO 2 via a sacrificial bridge-type ZnO layer for ethanol gas sensor

    KAUST Repository

    Lee, Da Hoon

    2017-08-05

    The progress in developing the microelectromechanical system (MEMS) heater-based SnO2 gas sensors was hindered by the subsequent heat treatment of the tin oxide (SnO2), nevertheless it is required to obtain excellent sensor characteristics. During the sintering process, the MEMS heater and the contact electrodes can be degraded at such a high temperature, which could reduce the sensor response and reliability. In this research, we presented a process of preheating the printed SnO2 sensing layer on top of a sacrificial bridge-type ZnO layer at such a high temperature, followed by transferring it onto the contact electrodes of sensor device by selective etching of the sacrificial ZnO layer. Therefore, the sensor device was not exposed to the high sintering temperature. The SnO2 gas sensor fabricated by the transfer process exhibited a rectangular sensing curve behavior with a rapid response of 52 s at 20 ppm ethanol concentration. In addition, reliable and repeatable sensing characteristics were obtained even at an ethanol gas concentration of 5 ppm.

  6. Tetramethylene glycol mediated hydrothermal synthesis of defect-rich SnO2 nanoparticles for fast adsorption and degradation of MB dye

    Science.gov (United States)

    Rani, Barkha; Jadhao, Charushila Vasant; Sahu, Niroj Kumar

    2018-04-01

    Defect-rich pristine tin oxide nanoparticles (SnO2 NPs) with high colloidal stability have been synthesized by tetramethylene glycol (TMG) mediated hydrothermal process and characterized by XRD, TEM, Zeta Potential, PL spectroscopy and porosity measurement techniques. XRD result suggests the formation of rutile phase of SnO2 with average crystallite size of 2.65 nm. TMG act as a structure directing agent assist in the formation of network like structure of SnO2 NPs as confirmed from TEM. Significant blue shifts in the UV absorption spectrum as that of the bulk and defect bands in the PL spectrum are observed. The nanomaterial possesses very high surface area of 263.102 m2/g and large pore volume. The above properties strongly influence the photocatalytic degradation of methylene blue dye. Very fast adsorption and 96% degradation (under UV irradiation) has been achieved when 10 ppm methylene blue solutions is catalysed by 20 mg SnO2 NPs which pave the way for potential environmental application.

  7. Phosphorus Enhanced Intermolecular Interactions of SnO2 and Graphene as an Ultrastable Lithium Battery Anode.

    Science.gov (United States)

    Zhang, Lei; Zhao, Kangning; Yu, Ruohan; Yan, Mengyu; Xu, Wangwang; Dong, Yifan; Ren, Wenhao; Xu, Xu; Tang, Chunjuan; Mai, Liqiang

    2017-05-01

    SnO 2 suffers from fast capacity fading in lithium-ion batteries due to large volume expansion as well as unstable solid electrolyte interphase. Herein, the design and synthesis of phosphorus bridging SnO 2 and graphene through covalent bonding are demonstrated to achieve a robust structure. In this unique structure, the phosphorus is able to covalently "bridge" graphene and tin oxide nanocrystal through PC and SnOP bonding, respectively, and act as a buffer layer to keep the structure stable during charging-discharging. As a result, when applied as a lithium battery anode, SnO 2 @P@GO shows very stable performance and retains 95% of 2nd capacity onward after 700 cycles. Such unique structural design opens up new avenues for the rational design of other high-capacity materials for lithium battery, and as a proof-of-concept, creates new opportunities in the synthesis of advanced functional materials for high-performance energy storage devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Hydrothermal synthesis of Ti oxide nanostructures and TiO2:SnO2 heterostructures applied to the photodegradation of rhodamine B

    International Nuclear Information System (INIS)

    Mourão, Henrique A.J.L.; Junior, Waldir Avansi; Ribeiro, Caue

    2012-01-01

    The present study describes the synthesis, characterization and testing of the photocatalytic potential of TiO 2 nanoparticles (NPs), TiO 2 :SnO 2 heterostructures and potassium titanate nanotubes (TNTs) obtained by the alkaline hydrothermal method. The materials were characterized by X-ray diffraction (XRD), energy-dispersive X-ray (EDX) spectroscopy, surface area estimated from the N 2 physisorption isotherm (BET), X-ray absorption near-edge structure (XANES) spectroscopy, scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), scanning transmission electron microscopy (STEM) and Fourier transform near-infrared (FT-NIR) spectroscopy, among other methods. Photocatalytic potential was assessed by rhodamine B dye photodegradation under UVC radiation. The properties of the materials were shown to depend on the KOH concentration. Potassium TNTs with high surface area were obtained only in 5 mol L −1 KOH. The material composed of TiO 2 anatase phase, which was obtained in KOH solution ranging from 10 −4 to 1 mol L −1 , showed higher photocatalytic activity than the TNTs, despite the lower surface area and lower density of hydroxyl groups on the anatase. In the heterostructure syntheses, SnO 2 NPs were identified attached to TiO 2 when 10 −4 and 10 −2 mol L −1 KOH were used, whereas at [KOH] = 1 and 5 mol L −1 , Sn remained in solution during the synthetic process and only the respective TiO 2 phase was identified. The TiO 2 :SnO 2 heterostructures were more active than the material without SnO 2 prepared at the same KOH concentrations. Highlights: ► The formation of the materials depends on the [KOH] used during syntheses. ► The heterostructures were obtained with the lower [KOH]. ► Photoactivity of the heterostructures was higher than the respective TiO 2 nanostructures. ► Titanate nanotubes showed high concentration of OH groups but low photoactivity.

  9. Ultra-Low-Power Smart Electronic Nose System Based on Three-Dimensional Tin Oxide Nanotube Arrays.

    Science.gov (United States)

    Chen, Jiaqi; Chen, Zhuo; Boussaid, Farid; Zhang, Daquan; Pan, Xiaofang; Zhao, Huijuan; Bermak, Amine; Tsui, Chi-Ying; Wang, Xinran; Fan, Zhiyong

    2018-06-04

    In this work, we present a high-performance smart electronic nose (E-nose) system consisting of a multiplexed tin oxide (SnO 2 ) nanotube sensor array, read-out circuit, wireless data transmission unit, mobile phone receiver, and data processing application (App). Using the designed nanotube sensor device structure in conjunction with multiple electrode materials, high-sensitivity gas detection and discrimination have been achieved at room temperature, enabling a 1000 times reduction of the sensor's power consumption as compared to a conventional device using thin film SnO 2 . The experimental results demonstrate that the developed E-nose can identify indoor target gases using a simple vector-matching gas recognition algorithm. In addition, the fabricated E-nose has achieved state-of-the-art sensitivity for H 2 and benzene detection at room temperature with metal oxide sensors. Such a smart E-nose system can address the imperative needs for distributed environmental monitoring in smart homes, smart buildings, and smart cities.

  10. Sputter-Deposited Indium–Tin Oxide Thin Films for Acetaldehyde Gas Sensing

    Directory of Open Access Journals (Sweden)

    Umut Cindemir

    2016-04-01

    Full Text Available Reactive dual-target DC magnetron sputtering was used to prepare In–Sn oxide thin films with a wide range of compositions. The films were subjected to annealing post-treatment at 400 °C or 500 °C for different periods of time. Compositional and structural characterizations were performed by X-ray photoelectron spectroscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, Rutherford backscattering and scanning electron microscopy. Films were investigated for gas sensing at 200 °C by measuring their resistance response upon exposure to acetaldehyde mixed with synthetic air. We found that the relative indium-to-tin content was very important and that measurable sensor responses could be recorded at acetaldehyde concentrations down to 200 ppb, with small resistance drift between repeated exposures, for both crystalline SnO2-like films and for amorphous films consisting of about equal amounts of In and Sn. We also demonstrated that it is not possible to prepare crystalline sensors with intermediate indium-to-tin compositions by sputter deposition and post-annealing up to 500 °C.

  11. Evaluation of Nd-Loaded SnO2:F Films Coated via Spray Pyrolysis

    Science.gov (United States)

    Turgut, G.

    2018-07-01

    Thin layers of single (F)- and double (F/Nd)-incorporated tin oxide have been coated on glass substrate via spray pyrolysis. The structural, morphological, electrical, and optical features of F-incorporated samples were evaluated depending on the Nd loading. X-ray diffraction analysis revealed that samples had tetragonal tin oxide structure with (211) and (200) preferential directions. The crystallite size and strain values varied from 37.98 nm and 1.21 × 10-3 to 52.12 nm and 1.88 × 10-3. Scanning electron microscopy analysis showed that the samples consisted of pyramidal, polyhedral, and needle-shaped granules. The lowest sheet resistance value of 1.22 Ω was found for 1.8 at.% Nd + 25 at.% F-coloaded SnO2. However, the widest optical bandgap of 4.01 eV was observed for the single 25 at.% F-loaded sample. The Urbach tail and figure of merit also changed in the ranges of 664 meV to 1296 meV and 6.4 × 10-2 Ω-1 to 2.3 × 10-3 Ω-1, respectively. The results presented herein indicate that the character of F-doped tin oxide films can be controlled by Nd loading and that these films could be useful for technological applications.

  12. SnO2 thin film synthesis for organic vapors sensing at ambient temperature

    Directory of Open Access Journals (Sweden)

    N.H. Touidjen

    2016-12-01

    Full Text Available The present work is a study of tin dioxide (SnO2 based thin sensitive layer dedicated to organic vapors detection at ambient temperature. SnO2 thin film was deposited by chemical spray pyrolysis technique. The glass substrate temperature was kept to 400 °C, using a starting solution of 0.1 M tin (II dichloride dihydrate (SnCl2, 2H2O. Films structural and morphological properties were characterized using X-ray diffraction (XRD, scanning electron microscopy (SEM and atomic force microscope (AFM respectively. Films optical characteristics were studied using UV-VIS spectrophotometer. XRD revealed the presence of pure SnO2 polycrystalline thin film with a tetragonal rutile structure. The SEM and AFM observations confirmed the granular morphology with presence of pores in the film surface. The prepared film was tested in various organic vapors (ethanol, methanol and acetone at ambient operating temperature (25 °C ± 2 °C. The obtained results suggested that SnO2 is more sensitive to ethanol vapor with a maximum sensitivity of 35% higher than to methanol and acetone vapors (1% and 3%. The realized SnO2 based sensor demonstrated fast response and recovery times as revealed by the values of 2 s to 3 s towards 47 ppm of ethanol vapor. Keywords: SnO2 thin film, Sensitivity, XRD, SEM, AFM, UV–visible

  13. Tin oxide transparent thin-film transistors

    International Nuclear Information System (INIS)

    Presley, R E; Munsee, C L; Park, C-H; Hong, D; Wager, J F; Keszler, D A

    2004-01-01

    A SnO 2 transparent thin-film transistor (TTFT) is demonstrated. The SnO 2 channel layer is deposited by RF magnetron sputtering and then rapid thermal annealed in O 2 at 600 deg. C. The TTFT is highly transparent, and enhancement-mode behaviour is achieved by employing a very thin channel layer (10-20 nm). Maximum field-effect mobilities of 0.8 cm 2 V -1 s -1 and 2.0 cm 2 V -1 s -1 are obtained for enhancement- and depletion-mode devices, respectively. The transparent nature and the large drain current on-to-off ratio of 10 5 associated with the enhancement-mode behaviour of these devices may prove useful for novel gas-sensor applications

  14. Grain size dependent electrical studies on nanocrystalline SnO2

    International Nuclear Information System (INIS)

    Bose, A. Chandra; Thangadurai, P.; Ramasamy, S.

    2006-01-01

    Nanocrystalline tin oxide (n-SnO 2 ) with different grain sizes were synthesized by chemical precipitation method. Size variation was achieved by changing the hydrolysis processing time. Structural phases of the nanocrystalline SnO 2 were identified by X-ray diffraction (XRD). The grain sizes of the prepared n-SnO 2 were found to be in the range 5-20 nm which were estimated using the Scherrer formula and they were confirmed by transmission electron microscopy (TEM) measurements. The electrical properties of nanocrystalline SnO 2 were studied using impedance spectroscopy. The impedance spectroscopy results showed that, in the temperature range between 25 and 650 deg. C, the conductivity has contributions from two different mechanisms, which are attributed to different conduction mechanisms in the grain and the grain boundary regions. This is because of the different relaxation times available for the conduction species in those regions. However, for the temperatures above 300 deg. C, there is no much difference between these two different relaxation times. The Arrhenius plots gave the activation energies for the conduction process in all the samples

  15. SnO2 Nanoparticles Decorated 2D Wavy Hierarchical Carbon Nanowalls with Enhanced Photoelectrochemical Performance

    Directory of Open Access Journals (Sweden)

    Noor Hamizah Khanis

    2017-01-01

    Full Text Available Two-dimensional carbon nanowall (2D-CNW structures were prepared by hot wire assisted plasma enhanced chemical vapor deposition (hw-PECVD system on silicon substrates. Controlled variations in the film structure were observed with increase in applied rf power during deposition which has been established to increase the rate of dissociation of precursor gases. The structural changes resulted in the formation of wavy-like features on the 2D-CNW, thus further enhancing the surface area of the nanostructures. The FESEM results confirmed the morphology transformation and conclusively showed the evolution of the 2D-CNW novel structures while Raman results revealed increase in ID/IG ratio indicating increase in the presence of disordered domains due to the presence of open edges on the 2D-CNW structures. Subsequently, the best 2D-CNW based on the morphology and structural properties was functionalized with tin oxide (SnO2 nanoparticles and used as a working electrode in a photoelectrochemical (PEC measurement system. Intriguingly, the SnO2 functionalized 2D-CNW showed enhancement in both Mott-Schottky profiles and LSV properties which suggested that these hierarchical networks showed promising potential application as effective charge-trapping medium in PEC systems.

  16. Low-temperature Synthesis of Tin(II) Oxide From Tin(II) ketoacidoximate Precursor

    KAUST Repository

    Alshankiti, Buthainah

    2015-01-01

    Sn (II) oxide finds numerous applications in different fields such as thin film transistors1, solar cells2 and sensors.3 In this study we present the fabrication of tin monoxide SnO by using Sn (II) ketoacid oximate complexes as precursors. Tin (II

  17. The effect of the film thickness and doping content of SnO2:F thin films prepared by the ultrasonic spray method

    International Nuclear Information System (INIS)

    Rahal Achour; Benramache Said; Benhaoua Boubaker

    2013-01-01

    This paper reports on the effects of film thickness and doping content on the optical and electrical properties of fluorine-doped tin oxide. Tin (II) chloride dehydrate, ammonium fluoride dehydrate, ethanol and HCl were used as the starting materials, dopant source, solvent and stabilizer, respectively. The doped films were deposited on a glass substrate at different concentrations varying between 0 and 5 wt% using an ultrasonic spray technique. The SnO 2 :F thin films were deposited at a 350 °C pending time (5, 15, 60 and 90 s). The average transmission was about 80%, and the films were thus transparent in the visible region. The optical energy gap of the doped films with 2.5 wt% F was found to increase from 3.47 to 3.89 eV with increasing film thickness, and increased after doping at 5 wt%. The decrease in the Urbach energy of the SnO 2 :F thin films indicated a decrease in the defects. The increase in the electrical conductivity of the films reached maximum values of 278.9 and 281.9 (Ω·cm) −1 for 2.5 and 5 wt% F, respectively, indicating that the films exhibited an n-type semiconducting nature. A systematic study on the influence of film thickness and doping content on the properties of SnO 2 :F thin films deposited by ultrasonic spray was reported. (semiconductor materials)

  18. Thermal transport properties of polycrystalline tin-doped indium oxide films

    International Nuclear Information System (INIS)

    Ashida, Toru; Miyamura, Amica; Oka, Nobuto; Sato, Yasushi; Shigesato, Yuzo; Yagi, Takashi; Taketoshi, Naoyuki; Baba, Tetsuya

    2009-01-01

    Thermal diffusivity of polycrystalline tin-doped indium oxide (ITO) films with a thickness of 200 nm has been characterized quantitatively by subnanosecond laser pulse irradiation and thermoreflectance measurement. ITO films sandwiched by molybdenum (Mo) films were prepared on a fused silica substrate by dc magnetron sputtering using an oxide ceramic ITO target (90 wt %In 2 O 3 and 10 wt %SnO 2 ). The resistivity and carrier density of the ITO films ranged from 2.9x10 -4 to 3.2x10 -3 Ω cm and from 1.9x10 20 to 1.2x10 21 cm -3 , respectively. The thermal diffusivity of the ITO films was (1.5-2.2)x10 -6 m 2 /s, depending on the electrical conductivity. The thermal conductivity carried by free electrons was estimated using the Wiedemann-Franz law. The phonon contribution to the heat transfer in ITO films with various resistivities was found to be almost constant (λ ph =3.95 W/m K), which was about twice that for amorphous indium zinc oxide films

  19. The optical and structural properties of graphene nanosheets and tin oxide nanocrystals composite

    Science.gov (United States)

    Farheen, Parveen, Azra; Azam, Ameer

    2018-05-01

    A nanocomposite material consisting of metal oxide and reduced graphene oxide was prepared via simple, economic, and effective chemical reduction method. The synthesis strategy was based on the reduction of GO with Sn2+ ion that combines tin oxidation and GO reduction in one step, which provides a simple, low-cost and effective way to prepare graphene nanosheets/SnO2 nanocrystals composites because no additional chemicals were needed. SEM and TEM images shows the uniform distribution of the SnO2 nanocrystals on the Graphene nanosheets (GNs) surface and transmission electron microscope shows an average particle size of 2-4 nm. The mean crystallite size was calculated by Debye Scherrer formula and was found to be about 4.0 nm. Optical analysis was done by using UV-Visible spectroscopy technique and the band gap energy of the GNs/SnO2 nanocomposite was calculated by Tauc relation and came out to be 3.43eV.

  20. Synthesis of nano-structured tin oxide thin films with faster response to LPG and ammonia by spray pyrolysis

    Science.gov (United States)

    PrasannaKumari, K.; Thomas, Boben

    2018-01-01

    Nanostructured SnO2 thin film have been efficiently fabricated by spray pyrolysis using atomizers of different types. The structure and morphology of as-prepared samples are investigated by techniques such as x-ray diffraction, and field-emission scanning electron microscopy. Significant morphological changes are observed in films by modifying the precursor atomization as a result of change of spray device. The optical characterization indicates that change in atomization, affects the absorbance and the band gap, following the varied crystallite size. Gas sensing investigations on ultrasonically prepared tin oxide films show NH3 response at operating temperatures lower down to 50 °C. For 1000 ppm of LPG the response at 350 °C for air blast atomizer film is about 99%, with short response and recovery times. The photoluminescence emmision spectra reveal the correlation between atomization process and the quantity of oxygen vacancies present in the samples. The favorable size reduction in microstructure with good crystallinity with slight change in lattice properties suggest their scope in gas sensing applications. On the basis of these characterizations, the mechanism of LPG and NH3 gas sensing of nanostructured SnO2 thin films has been proposed.

  1. The Optimum Fabrication Condition of p-Type Antimony Tin Oxide Thin Films Prepared by DC Magnetron Sputtering

    Directory of Open Access Journals (Sweden)

    Huu Phuc Dang

    2016-01-01

    Full Text Available Transparent Sb-doped tin oxide (ATO thin films were fabricated on quartz glass substrates via a mixed (SnO2 + Sb2O3 ceramic target using direct current (DC magnetron sputtering in ambient Ar gas at a working pressure of 2 × 10−3 torr. X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS, Hall-effect, and UV-vis spectra measurements were performed to characterize the deposited films. The substrate temperature of the films was investigated in two ways: (1 films were annealed in Ar ambient gas after being deposited at room temperature or (2 they were deposited directly at different temperatures. The first process for fabricating the ATO films was found to be easier than the second process. The deposited films showed p-type electrical properties, a polycrystalline tetragonal rutile structure, and their average transmittance was greater than 80% in the visible light range at the optimum annealing temperature of 500°C. The best electrical properties of the film were obtained on a 10 wt% Sb2O3-doped SnO2 target with a resistivity, hole concentration, and Hall mobility of 0.55 Ω·cm, 1.2 × 1019 cm−3, and 0.54 cm2V−1s−1, respectively.

  2. Synthesis And Characterization Of SiO2, SnO2 And TiO2 Metal Oxide Shells Covering Cu2O Particles

    Directory of Open Access Journals (Sweden)

    Yu Ri

    2015-06-01

    Full Text Available In this work is described a means of improving the chemical stability of Cu2O@SiO2, Cu2O@SnO2 and Cu2O@TiO2 materials. The SiO2, SnO2 and TiO2 coated samples were stable from pH 3 to pH 10 for up to seven days. To determine the stability of the coated nanoparticles, and their colloidal solutions under acidic and basic conditions, colloidal nanoparticle solutions with various pH values were prepared and monitored over time. Details of the effect of variations in pH on the phase stability of core-shell type Cu2O were characterized using transmission electron microscopy and X-ray diffraction.

  3. Effect of barrier layers on the properties of indium tin oxide thin films on soda lime glass substrates

    International Nuclear Information System (INIS)

    Lee, Jung-Min; Choi, Byung-Hyun; Ji, Mi-Jung; An, Yong-Tae; Park, Jung-Ho; Kwon, Jae-Hong; Ju, Byeong-Kwon

    2009-01-01

    In this paper, the electrical, structural and optical properties of indium tin oxide (ITO) films deposited on soda lime glass (SLG) haven been investigated, along with high strain point glass (HSPG) substrate, through radio frequency magnetron sputtering using a ceramic target (In 2 O 3 :SnO 2 , 90:10 wt.%). The ITO films deposited on the SLG show a high electrical resistivity and structural defects compared with those deposited on HSPG due to the Na ions from the SLG diffusing to the ITO film by annealing. However, these properties can be improved by intercalating a barrier layer of SiO 2 or Al 2 O 3 between the ITO film and the SLG substrate. SIMS analysis has confirmed that the barrier layer inhibits the Na ion's diffusion from the SLG. In particular, the ITO films deposited on the Al 2 O 3 barrier layer, show better properties than those deposited on the SiO 2 barrier layer.

  4. Controlling plasmonic properties of epitaxial thin films of indium tin oxide in the near-infrared region

    Science.gov (United States)

    Kamakura, R.; Fujita, K.; Murai, S.; Tanaka, K.

    2015-06-01

    Epitaxial thin films of indium tin oxide (ITO) were grown on yttria-stabilized zirconia single-crystal substrates by using a pulsed laser deposition to examine their plasmonic properties. The dielectric function of ITO was characterized by spectroscopic ellipsometry. Through the concentration of SnO2 in the target, the carrier concentration in the films was modified, which directly leads to the tuning of the dielectric function in the near-infrared region. Variable-angle reflectance spectroscopy in the Kretschmann geometry shows the dip in the reflection spectrum of p-polarized light corresponding to the excitation of surface plasmon polaritions (SPPs) in the near-infrared region. The excitation wavelength of the SPPs was shifted with changing the dielectric functions of ITO, which is reproduced by the calculation using transfer matrix method.

  5. Wet etching mechanism and crystallization of indium-tin oxide layer for application in light-emitting diodes

    Science.gov (United States)

    Su, Shui-Hsiang; Kong, Hsieng-Jen; Tseng, Chun-Lung; Chen, Guan-Yu

    2018-01-01

    In the article, we describe the etching mechanism of indium-tin oxide (ITO) film, which was wet-etched using a solution of hydrochloric acid (HCl) and ferric chloride (FeCl3). The etching mechanism is analyzed at various etching durations of ITO films by scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HR-TEM), and selective area diffraction (SAD) analysis. In comparison with the crystalline phase of SnO2, the In2O3 phase can be more easily transformed to In3+ and can form an inverted conical structure during the etching process. By adjusting the etching duration, the residual ITO is completely removed to show a designed pattern. This is attributed to the negative Gibbs energy of In2O3 transformed to In3+. The result also corresponds to the finding of energy-dispersive X-ray spectroscopy (EDS) analysis that the Sn/In ratio increases with increasing etching duration.

  6. Deposition of tin oxide doped with fluorine produced by sol-gel method and deposited by spray-pyrolysis

    International Nuclear Information System (INIS)

    Maia, Paulo Herbert Franca; Lima, Francisco Marcone; Sena, Aline Cosmo de; Silva, Alvaro Neuton; Almeida, Ana Fabiola Leite de; Freire, Francisco Nivaldo Aguiar

    2014-01-01

    Solar energy is one of the most important sources of renewable energy today, but its production is based on silicon cells, expensive and difficult to produce, so the research seek new materials to replace them. This work aims to deposit tin oxide doped with fluorine on the glass substrate using the sol-gel method to provide a working solution and spray pyrolysis technique to perform the deposition. F-SnO2 (FTO) were synthesized by sol-gel method, employing NH_4F and SnCl_2 precursor in an ethanol solution. Before the formation of the gel phase, the entire solution was sprayed, with the aid of a pistol aerographic substrate under heated at 600 °C divided by 50 applications and cooled in the furnace. The substrates had resistances between 10 and 30 S.cm. The energy dispersive x-ray (EDS) revealed the presence of fluorine in the SnO_2 network. (author)

  7. Gas Sensing Studies of an n-n Hetero-Junction Array Based on SnO2 and ZnO Composites

    Directory of Open Access Journals (Sweden)

    Anupriya Naik

    2016-02-01

    Full Text Available A composite metal oxide semiconductor (MOS sensor array based on tin dioxide (SNO2 and zinc oxide (ZnO has been fabricated using a straight forward mechanical mixing method. The array was characterized using X-ray photoelectron spectroscopy, scanning electron microscopy, Raman spectroscopy and X-ray diffraction. The array was evaluated against a number of environmentally important reducing and oxidizing gases across a range of operating temperatures (300–500 °C. The highest response achieved was against 100 ppm ethanol by the 50 wt% ZnO–50 wt% SnO2 device, which exhibited a response of 109.1, a 4.5-fold increase with respect to the pure SnO2 counterpart (which displayed a response of 24.4 and a 12.3-fold enhancement with respect to the pure ZnO counterpart (which was associated with a response of 8.9, towards the same concentration of the analyte. Cross sensitivity studies were also carried out against a variety of reducing gases at an operating temperature of 300 °C. The sensors array showed selectivity towards ethanol. The enhanced behaviour of the mixed oxide materials was influenced by junction effects, composition, the packing structure and the device microstructure. The results show that it is possible to tune the sensitivity and selectivity of a composite sensor, through a simple change in the composition of the composite.

  8. Physical properties of electrically conductive Sb-doped SnO2 transparent electrodes by thermal annealing dependent structural changes for photovoltaic applications

    International Nuclear Information System (INIS)

    Leem, J.W.; Yu, J.S.

    2011-01-01

    Highlights: · The physical properties of sputtered Sb-doped SnO 2 after annealing were studied. · The figure of merit was estimated from the integral PFD and sheet resistance. · The characteristics of Sb-doped SnO 2 films were optimized by the figure of merit. · An optimized Sb-doped SnO 2 layer is promising for high efficiency photovoltaic cells. - Abstract: We have investigated the optical and electrical characteristics of antimony (Sb)-doped tin oxide (SnO 2 ) films with modified structures by thermal annealing as a transparent conductive electrode. The structural properties were analyzed from the relative void % by spectroscopic ellipsometry as well as the scanning electron microscopy images and X-ray diffraction patterns. As the annealing temperature was raised, Sb-doped SnO 2 films exhibited a slightly enhanced crystallinity with the increase of the grain size from 17.1 nm at 500 deg. C to 34.3 nm at 700 deg. C. Furthermore, the refractive index and extinction coefficient gradually decreased due to the increase in the relative void % within the film during the annealing. The resistivity decreased to 8.2 x 10 -3 Ω cm at 500 deg. C, but it increased rapidly at 700 deg. C. After thermal annealing, the optical transmittance was significantly increased. For photovoltaic applications, the photonic flux density and the figure of merit over the entire solar spectrum were obtained, indicating the highest values of 5.4 x 10 14 cm -2 s -1 nm -1 at 1.85 eV after annealing at 700 deg. C and 340.1 μA cm -2 Ω -1 at 500 deg. C, respectively.

  9. An Investigation of Structural and Electrical Properties of Nano Crystalline SnO2:Cu Thin Films Deposited by Spray Pyrolysis

    Directory of Open Access Journals (Sweden)

    J. Podder

    2011-11-01

    Full Text Available Pure tin oxide (SnO2 and Cu doped SnO2 thin films have been deposited onto glass substrates by a simple spray pyrolysis technique under atmospheric pressure at temperature 350 °C. The doping concentration of Cu was varied from 1 to 8 wt. % while all other deposition parameters such as spray rate, carrier air gas pressure, deposition time, and distance between spray nozzle to substrate were kept constant. Surface morphology of the as-deposited thin films has been studied by Scanning Electron Microscopy (SEM. The SEM micrograph of the films shows uniform deposition. The structural properties of the as-deposited and annealed thin films have been studied by XRD and the electrical characterization was performed by Van-der Pauw method. The as-deposited films are found polycrystalline in nature with tetragonal crystal structure. Average grain sizes of pure and Cu doped SnO2 thin film have been obtained in the range of 7.2445 Å to 6.0699 Å, which indicates the nanometric size of SnO2 grains developed in the film. The resistivity of SnO2 films was found to decrease initially from 4.5095×10−4 Ωm to 1.1395× 10−4 Ωm for concentration of Cu up to 4 % but it was increased further with increasing of Cu concentrations. The experimental results depict the suitability of this material for using as transparent and conducting window materials in solar cells and gas sensors.

  10. Facile synthesis of low-dimensional SnO2 nanostructures: An investigation of their performance and mechanism of action as anode materials for lithium-ion batteries

    Science.gov (United States)

    Usman Hameed, Muhammad; Ullah Dar, Sami; Ali, Shafqat; Liu, Sitong; Akram, Raheel; Wu, Zhanpeng; Butler, Ian S.

    2017-07-01

    Owing to high-energy density of rechargeable lithium-ion batteries (LIBs), they have been investigated as an efficient electrochemical power sources for various energy applications. High theoretical capacities of tin oxide (SnO2) anodes have led us a path to meet the ever-growing demands in the development of high-performance electrode materials for LIBs. In this paper, a facile approach is described for the synthesis of porous low-dimensional nanoparticles and nanorods of SnO2 for application in LIBs with the help of Tween-80 as a surfactant. The SnO2 samples synthesized at different reaction temperatures produced porous nanoparticles and nanorods with average diameters of 7-10 nm and 70-110 nm, respectively. The SnO2 nanoparticle electrodes exhibit a high reversible charge capacity of 641.1 mAh/g at 200 mA/g after 50 cycles, and a capacity of 340 mAh/g even at a high current density of 1000 mA/g during the rate tests, whereas the porous nanorod electrodes delivers only 526.3 mAh/g at 200 mA/g after 50 cycles and 309.4 mAh/g at 1000 mA/g. It is believed that finer sized SnO2 nanoparticles are much more favorable to trap more Li+ ion during electrochemical cycling, resulting in a large irreversible capacity. In contrast, rapid capacity fading was observed for the porous nanorods, which is the result of their pulverization resulting from repeated cycling.

  11. Preparation and Characterization of Nanocomposite Polymer Membranes Containing Functionalized SnO2 Additives

    Directory of Open Access Journals (Sweden)

    Roberto Scipioni

    2014-03-01

    Full Text Available In the research of new nanocomposite proton-conducting membranes, SnO2 ceramic powders with surface functionalization have been synthesized and adopted as additives in Nafion-based polymer systems. Different synthetic routes have been explored to obtain suitable, nanometer-sized sulphated tin oxide particles. Structural and morphological characteristics, as well as surface and bulk properties of the obtained oxide powders, have been determined by means of X-ray diffraction (XRD, scanning electron microscopy (SEM, Fourier Transform Infrared (FTIR and Raman spectroscopies, N2 adsorption, and thermal gravimetric analysis (TGA. In addition, dynamic mechanical analysis (DMA, atomic force microscopy (AFM, thermal investigations, water uptake (WU measurements, and ionic exchange capacity (IEC tests have been used as characterization tools for the nanocomposite membranes. The nature of the tin oxide precursor, as well as the synthesis procedure, were found to play an important role in determining the morphology and the particle size distribution of the ceramic powder, this affecting the effective functionalization of the oxides. The incorporation of such particles, having sulphate groups on their surface, altered some peculiar properties of the resulting composite membrane, such as water content, thermo-mechanical, and morphological characteristics.

  12. Enhanced electrochemical oxidation of synthetic dyeing wastewater using SnO2-Sb-doped TiO2-coated granular activated carbon electrodes with high hydroxyl radical yields

    International Nuclear Information System (INIS)

    Li, Xinyang; Wu, Yue; Zhu, Wei; Xue, Fangqing; Qian, Yi; Wang, Chengwen

    2016-01-01

    Highlights: • We study granular activated carbon (GAC) electrodes coated with catalysts. • GAC coated with ATOT demonstrates an impressive ·OH yield. • This electrode can be used in continuous-flow three-dimensional electrode reactors. • We use Rhodamine B as a model organic compound for removal. • The GAC/ATOT performs better than all other electrodes examined. - Abstract: In this study, granular activated carbon (GAC) coated with SnO 2 -Sb doped TiO 2 (GAC/ATOT) with a high hydroxyl radical (·OH) yield is prepared via the sol-gel method. This material is utilized as a granular electrode in a continuous-flow three-dimensional electrode reactor (CTDER) for the enhanced treatment of synthetic dyeing wastewater containing Rhodamine B (RhB). We then characterize the physical properties, electrochemical properties, and electrochemical oxidation performance of the granular electrode. The results show that using the GAC/ATOT electrode in a CTDER significantly enhances the chemical oxygen demand (COD) removal, decreases the energy consumption, and improves the current efficiency of the wastewater. This is primarily attributed to the higher catalytic activity of GAC/ATOT for ·OH production compared to that of other candidates, such as TiO 2 coated GAC (GAC/T), Sb doped SnO 2 coated GAC (GAC/ATO), and pure GAC. The mechanism of the enhanced electrochemical oxidation afforded by using GAC/ATOT indicates that the high ·OH yield in the reactor packed with GAC/ATOT electrodes contributes to the enhanced electrochemical oxidation performance with respect to organic compounds.

  13. Properties of Resistive Hydrogen Sensors as a Function of Additives of 3 D-Metals Introduced in the Volume of Thin Nanocrystalline SnO2 Films

    Science.gov (United States)

    Sevast'yanov, E. Yu.; Maksimova, N. K.; Potekaev, A. I.; Sergeichenko, N. V.; Chernikov, E. V.; Almaev, A. V.; Kushnarev, B. O.

    2017-11-01

    Analysis of the results of studying electrical and gas sensitive characteristics of the molecular hydrogen sensors based on thin nanocrystalline SnO2 films coated with dispersed Au layers and containing Au+Ni and Au+Co impurities in the bulk showed that the characteristics of these sensors are more stable under the prolonged exposure to hydrogen in comparison with Au/SnO2:Sb, Au films modified only with gold. It has been found that introduction of the nickel and cobalt additives increases the band bending at the grain boundaries of tin dioxide already in freshly prepared samples, which indicates an increase in the density Ni of the chemisorbed oxygen. It is important that during testing, the band bending eφs at the grain boundaries of tin dioxide additionally slightly increases. It can be assumed that during crystallization of films under thermal annealing, the 3d-metal atoms in the SnO2 volume partially segregate on the surface of microcrystals and form bonds with lattice oxygen, the superstoichiometric tin atoms are formed, and the density Ni increases. If the bonds of oxygen with nickel and cobalt are stronger than those with tin, then, under the prolonged tests, atomic hydrogen will be oxidized not by lattice oxygen, but mainly by the chemisorbed one. In this case, stability of the sensors' characteristics increases.

  14. Multi-band emission in a wide wavelength range from tin oxide/Au nanocomposites grown on porous anodic alumina substrate (AAO)

    International Nuclear Information System (INIS)

    Norek, Małgorzata; Michalska-Domańska, Marta; Stępniowski, Wojciech J.; Ayala, Israel; Bombalska, Aneta; Budner, Bogusław

    2013-01-01

    The photoluminescence (PL) properties of tin oxide nanostructures are investigated. Three samples of different morphology, induced by deposition process and various geometrical features of nanoporous anodic aluminum oxide (AAO) substrate, are analyzed. X-ray photoelectronic spectroscopy (XPS) analysis reveals the presence of two forms of tin oxide on the surface of all studied samples: SnO and SnO 2 . The former form is typical for reduced surface with bridging oxygen atoms and every other row of in-plane oxygen atoms removed. The oxygen defects give rise to a strong emission in visible region. Two intense PL peaks are observed centered at about 540 (band I) and 620 (band II) nm. The origin of these bands was ascribed to the recombination of electrons from the conduction band (band I) and shallow traps levels (band II) to the surface oxygen vacancy levels. Upon deposition of Au nanoparticles on the top of tin oxide nanostructures the emission at 540 and 620 nm disappears and a new band (band III) occurs in the range >760 nm. The PL mechanism operating in the studied systems is discussed. The tin oxide/Au nanocomposites can be used as efficient multi-band light emitters in a wide (from visible to near infrared) wavelength range.

  15. Positron annihilation study of YBa2Cu3Oy superconductors doped with SnO2

    International Nuclear Information System (INIS)

    Chen, A.; Zhi, Y.; Li Biaorong; Wang Shaojie

    1992-01-01

    The positron annihilation lifetime spectra of YBa 2 Cu 3 O y superconductors doped with SnO 2 were measured. The results indicate that the tin element substitutes for Cu(1) sites. A brief discussion is given based on the experimental results. (orig.)

  16. Characteristics of nano Ti-doped SnO2 powders prepared by sol-gel method

    International Nuclear Information System (INIS)

    Liu, X.M.; Wu, S.L.; Chu, Paul K.; Zheng, J.; Li, S.L.

    2006-01-01

    Ti 4+ -doped SnO 2 nano-powders were prepared by the sol-gel process using tin tetrachloride and titanium tetrachloride as the starting materials. The crystallinity and purity of the powders were analyzed by X-ray diffraction (XRD) and the size and distribution of Ti 4+ -doped SnO 2 grains were studied using transmission electron microscopy (TEM) and scanning electron microscopy (SEM). The results show that Ti 4+ has been successfully incorporated into the SnO 2 crystal lattice and the electrical conductivity of the doped materials improves significantly

  17. A facile hydrothermal strategy for synthesis of SnO2 nanorods-graphene nanocomposites for high performance photocatalysis.

    Science.gov (United States)

    Chen, Lu-Ya; Zhang, Wei-De; Xu, Bin; Yu, Yu-Xiang

    2012-09-01

    In this study, we report a facilely hydrothermal process for synthesizing SnO2 nanorods-graphene (SnO2 nanorods-GR) composite using graphite oxide and SnCl4 as raw materials. The SnO2 nanorods-GR composite was characterized by X-ray diffraction, electron microscopy, Xray photoelectron spectroscopy, and thermogravimetric analysis. Compared to commercial TiO2 nanoparticles P25 and neat SnO2 nanorods, the SnO2 nanorods-GR composite exhibits higher photocatalytic activity under UV light irradiation. The mechanism of its high photocatalytic activity is mainly ascribed to the synergy effect between SnO2 and graphene, in which graphene acts as an adsorbent and electron acceptor due to its large structure of pi-pi conjugation from sp2 hybrid carbon atoms. The results demonstrated in this study provide a promising way to enhance the photocatalytic activity by compounding semiconductive nanocrystals with graphene.

  18. Binding SnO2 nanocrystals in nitrogen-doped graphene sheets as anode materials for lithium-ion batteries.

    Science.gov (United States)

    Zhou, Xiaosi; Wan, Li-Jun; Guo, Yu-Guo

    2013-04-18

    Hybrid anode materials for Li-ion batteries are fabricated by binding SnO2 nanocrystals (NCs) in nitrogen-doped reduced graphene oxide (N-RGO) sheets by means of an in situ hydrazine monohydrate vapor reduction method. The SnO2NCs in the obtained SnO2NC@N-RGO hybrid material exhibit exceptionally high specific capacity and high rate capability. Bonds formed between graphene and SnO2 nanocrystals limit the aggregation of in situ formed Sn nanoparticles, leading to a stable hybrid anode material with long cycle life. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Preparation and optical properties of Eu3+-doped tin oxide nanoparticles

    International Nuclear Information System (INIS)

    Wang, Guofeng; Yang, Yiping; Mu, Qiuying; Wang, Yude

    2010-01-01

    Eu 3+ -doped SnO 2 nanoparticles with high surface area were generated within the template of the cationic surfactant (cetyltrimethylammonium bromide, CTAB) micelle assembly by surfactant-mediated method from the hydrous tin chloride (SnCl 4 .5H 2 O) and europium chloride (EuCl 3 .6H 2 O). The as-synthesized product was amorphous and transformed into crystalline calcined at 500 o C for 2 h. DSC-TGA, X-ray powder diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were used to examine the morphology and microstructure of the final products. The results showed that the Eu 3+ -doped SnO 2 nanoparticles with diameter of 3-7 nm were obtained. The influences of the molar ratios of Eu 3+ and CTAB on the room temperature photoluminescence (RTPL) properties of Eu 3+ -doped SnO 2 nanoparticles were investigated. The results showed that the contents of Eu 3+ and CTAB had a great influence on the crystallite sizes and RTPL properties of Eu 3+ :SnO 2 nanoparticles. The maximum of the RTPL intensity can be observed at the molar ratio 5.0% Eu 3+ and 10.0% CTAB.

  20. Conductive framework supported high rate performance of SnO2 hollow nanofibers for lithium battery anodes

    International Nuclear Information System (INIS)

    Pham-Cong, De; Kim, Ji Yoon; Park, Jung Soo; Kim, Jae Hyun; Kim, Jong-Pil; Jeong, Euh-Duck; Kim, Jinwoo; Jeong, Se-Young; Cho, Chae-Ryong

    2015-01-01

    We synthesized an electrospun SnO 2 hollow nanofibers (SnO 2 hNFs) coated with carbon and wrapped with graphene oxide layer by simple hydrothermal and electrostatic force method, respectively. Thin carbon layer as electrolyte blocking layer was formed on the SnO 2 hNFs by using glucose as a carbon source (SnO 2 @C hNFs). Also, layers of graphene oxide are wrapped on SnO 2 @C hNFs by the electrostatic interaction force (SnO 2 @C@G hNFs). At high C rate, the average capacity of the SnO 2 @C@G hNFs still kept high capacity comparing with the SnO 2 hNFs and SnO 2 @C hNFs and then increased above 250% at 3 C. It also exhibits a greatly enhanced synergic effect with an extremely high lithium storage capability up to 1,600 mA h g −1 and kept 900 mA h g −1 after 50 cycles benefiting from the advanced structural features

  1. Densificação rápida de cerâmicas de SnO2 Fast densification of SnO2 ceramics

    Directory of Open Access Journals (Sweden)

    G. J. Pereira

    2003-04-01

    Full Text Available Os pós à base de óxido de estanho são conhecidos por apresentarem baixa densificação mesmo a temperaturas de sinterização acima de 1500 °C. A introdução de diferentes íons metálicos como Mn2+, Fe3+ e Cu2+ induzem a redução do volume de poros e crescimento de grãos durante a sinterização. Pós à base de SnO2 foram preparados pela rota química derivada da patente de Pechini, contendo diferentes concentrações de Mg2+ ou Fe3+. Todas as amostras apresentaram uma alta taxa de densificação nos momentos iniciais, quando sinterizadas por "fast firing". As amostras contendo 5% em mol de ferro sinterizadas durante 30 s a 1200 °C apresentaram densidades superiores às amostras sinterizadas por aquecimento em taxas normais (10 °C/min por 4 h a 1200 °C. O fenômeno de eliminação rápida de poros pode ser explicado, levando em conta o papel da superfície no fenômeno de sinterização. A saturação da superfície pelo aditivo foi confirmada por medidas de mobilidade eletroforética dinâmica com base na literatura e em dados experimentais.Tin oxide based powders without additives present low densification even at high sintering temperatures. Different metal cations such as Fe3+, Mn2+ and Cu2+ are introduced into such powders and induce pore volume reduction during sintering. In this work, SnO2 based powders were prepared with different amounts of Mg2+ and Fe3+ by a polymeric chemical process derived from Pechini's method. All samples presented high initial densification rate when sintered by fast firing. SnO2 samples containing 5 mol % of iron ions and sintered by fast firing at 1200 °C during 30 s were denser than samples with the same composition but sintered by conventional method, e.g., 1200 °C during 4 h at 10 °C/min. The fast densification could be understood considering the role of the surface on the sintering phenomenon. The surface saturation was verified by electrokinetic mobility measurements and reported results.

  2. Synthesis and characterization of inorganic ion exchangers based on mixed oxide tin-titanium to be used in recovery of cadmium and nickel and photoluminescent studies

    International Nuclear Information System (INIS)

    Paganini, Paula Pinheiro

    2007-01-01

    This work presents the synthesis, characterization and adsorption studies of inorganic ion exchangers based on mixed tin-titanium oxide for recovery of cadmium and nickel metals from aqueous effluents, discarded in the environment mainly through Ni-Cd battery. The exchangers were synthesized by sol-gel modified method using a mixture of tin(IV) chloride and titanium(III) chloride and ammonium hydroxide, as precursors reagents. The materials obtained: SnO 2 /TiO 2 and SnO 2 /TiO 2 :Eu 3+ were characterized by infrared spectroscopy, thermal analysis, scattering electronic microscopy (SEM), X-ray powder diffraction (XRD) (powder method) and electronic spectroscopy (excitation and emission) for the europium doped exchanger. The same materials also were synthesized in polymeric matrix too and can be used in column, because the synthesized materials showed crystals size in nano metric scale. It was determined by the distribution ratios for metals taking as parameters the influence of pH, the concentration of metals (by adsorption isotherms) and the contact time (by adsorption kinetic). The inorganic ion exchanger presented high exchange capacity with adsorption percent above 90 por cent for the studied conditions, quickly kinetic, heterogeneous exchange surfaces, physic adsorption and spontaneous process of exchange. To the doped exchanger spectroscopy properties were studied and also it was calculated the intensity parameters and it was found a satisfactory quantum yield. (author)

  3. Designed hybrid nanostructure with catalytic effect: beyond the theoretical capacity of SnO2 anode material for lithium ion batteries

    OpenAIRE

    Wang, Ye; Huang, Zhi Xiang; Shi, Yumeng; Wong, Jen It; Ding, Meng; Yang, Hui Ying

    2015-01-01

    Transition metal cobalt (Co) nanoparticle was designed as catalyst to promote the conversion reaction of Sn to SnO2 during the delithiation process which is deemed as an irreversible reaction. The designed nanocomposite, named as SnO2/Co3O4/reduced-graphene-oxide (rGO), was synthesized by a simple two-step method composed of hydrothermal (1st step) and solvothermal (2nd step) synthesis processes. Compared to the pristine SnO2/rGO and SnO2/Co3O4 electrodes, SnO2/Co3O4/rGO nanocomposites exhibi...

  4. Optical and Electrical Properties of Tin-Doped Cadmium Oxide Films Prepared by Electron Beam Technique

    Science.gov (United States)

    Ali, H. M.; Mohamed, H. A.; Wakkad, M. M.; Hasaneen, M. F.

    2009-04-01

    Tin-doped cadmium oxide films were deposited by electron beam evaporation technique. The structural, optical and electrical properties of the films were characterized. The X-ray diffraction (XRD) study reveals that the films are polycrystalline in nature. As composition and structure change due to the dopant ratio and annealing temperature, the carrier concentration was varied around 1020 cm-3, and the mobility increased from less than 10 to 45 cm2 V-1 s-1. A transmittance value of ˜83% and a resistivity value of 4.4 ×10-4 Ω cm were achieved for (CdO)0.88(SnO2)0.12 film annealed at 350 °C for 15 min., whereas the maximum value of transmittance ˜93% and a resistivity value of 2.4 ×10-3 Ω cm were obtained at 350 °C for 30 min. The films exhibited direct band-to-band transitions, which corresponded to optical band gaps of 3.1-3.3 eV.

  5. Synthesis of Antimony Doped Tin Oxide and its Use as Electrical Humidity Sensor

    Directory of Open Access Journals (Sweden)

    B. C. Yadav

    2008-05-01

    Full Text Available In this paper we report the humidity sensitive electrical properties of antimony doped tin oxide. Antimony has been doped within SnO2 in the ratio 1:1. The pellet has been made by hydraulic pressing machine at pressure 30 MPa and room temperature 24°C. This pellet, has been annealed at 200ºC, 300ºC, 400ºC, 500ºC and 600ºC successively for 3 hrs and after each step annealing, observations were taken. It has been observed, as Relative Humidity (%RH increases, there is decrease in the resistivity of pellet for the entire range of RH i.e. from 10% to 95%. Linear decrease is observed for the range of RH from 10% to 85% for annealing temperature 200ºC and 300ºC, from 10% to 60% for annealing temperature 400ºC and from 10% to 30% for annealing temperature 500ºC and 600ºC respectively. Scanning electron micrographs show the surface morphology and X-ray diffraction reveals the nanostructure of sensing element. Results have been found reproducible with hysterisis of ± 2% after 3 months.

  6. Ultrafine tin oxide on reduced graphene oxide as high-performance anode for sodium-ion batteries

    International Nuclear Information System (INIS)

    Zhang, Yandong; Xie, Jian; Zhang, Shichao; Zhu, Peiyi; Cao, Gaoshao; Zhao, Xinbing

    2015-01-01

    Highlights: • A nanohybrid based on ultrafine SnO 2 and few-layered rGO has been prepared. • The nanohybrid exhibits excellent electrochemical Na-storage properties. • The rGO supplies combined conducting, buffering and dispersing effects. - Abstract: Na-ion Battery is attractive alternative to Li-ion battery due to the natural abundance of sodium resource. Searching for suitable anode materials is one of the critical issues for Na-ion battery due to the low Na-storage activity of carbon materials. In this work, we synthesized a nanohybrid anode consisting of ultrafine SnO 2 anchored on few-layered reduced graphene oxide (rGO) by a facile hydrothermal route. The SnO 2 /rGO hybrid exhibits a high capacity, long cycle life and good rate capability. The hybrid can deliver a high charge capacity of 324 mAh g SnO2 −1 at 50 mA g −1 . At 1600 mA g −1 (2.4C), it can still yield a charge capacity of 200 mAh g SnO2 −1 . After 100 cycles at 100 mA g −1 , the hybrid can retain a high charge capacity of 369 mAh g SnO2 −1 . X-ray photoelectron spectroscopy, ex situ transmission electron microscopy and electrochemical impedance spectroscopy were used to investigate the origin of the excellent electrochemical Na-storage properties of SnO 2 /rGO

  7. Effect of Source/Drain Electrodes on the Electrical Properties of Silicon–Tin Oxide Thin-Film Transistors

    Directory of Open Access Journals (Sweden)

    Xianzhe Liu

    2018-05-01

    Full Text Available Ultra-high definition displays have become a trend for the current flat plane displays. In this study, the contact properties of amorphous silicon–tin oxide thin-film transistors (a-STO TFTs employed with source/drain (S/D electrodes were analyzed. Ohmic contact with a good device performance was achieved when a-STO was matched with indium-tin-oxide (ITO or Mo electrodes. The acceptor-like densities of trap states (DOS of a-STO TFTs were further investigated by using low-frequency capacitance–voltage (C–V characteristics to understand the impact of the electrode on the device performance. The reason of the distinct electrical performances of the devices with ITO and Mo contacts was attributed to different DOS caused by the generation of local defect states near the electrodes, which distorted the electric field distribution and formed an electrical potential barrier hindering the flow of electrons. It is of significant importance for circuit designers to design reliable integrated circuits with SnO2-based devices applied in flat panel displays.

  8. Catalyst engineering for lithium ion batteries: the catalytic role of Ge in enhancing the electrochemical performance of SnO2(GeO2)0.13/G anodes.

    Science.gov (United States)

    Zhu, Yun Guang; Wang, Ye; Han, Zhao Jun; Shi, Yumeng; Wong, Jen It; Huang, Zhi Xiang; Ostrikov, Kostya Ken; Yang, Hui Ying

    2014-12-21

    The catalytic role of germanium (Ge) was investigated to improve the electrochemical performance of tin dioxide grown on graphene (SnO(2)/G) nanocomposites as an anode material of lithium ion batteries (LIBs). Germanium dioxide (GeO(20) and SnO(2) nanoparticles (GeO(2))0.13/G nanocomposites can deliver a capacity of 1200 mA h g(-1) at a current density of 100 mA g(-1), which is much higher than the traditional theoretical specific capacity of such nanocomposites (∼ 702 mA h g(-1)). More importantly, the SnO(2)(GeO(2))0.13/G nanocomposites exhibited an improved rate, large current capability (885 mA h g(-1) at a discharge current of 2000 mA g(-1)) and excellent long cycling stability (almost 100% retention after 600 cycles). The enhanced electrochemical performance was attributed to the catalytic effect of Ge, which enabled the reversible reaction of metals (Sn and Ge) to metals oxide (SnO(2) and GeO(2)) during the charge/discharge processes. Our demonstrated approach towards nanocomposite catalyst engineering opens new avenues for next-generation high-performance rechargeable Li-ion batteries anode materials.

  9. Honeycomb-inspired design of ultrafine SnO2@C nanospheres embedded in carbon film as anode materials for high performance lithium- and sodium-ion battery

    Science.gov (United States)

    Ao, Xiang; Jiang, Jianjun; Ruan, Yunjun; Li, Zhishan; Zhang, Yi; Sun, Jianwu; Wang, Chundong

    2017-08-01

    Tin oxide (SnO2) has been considered as one of the most promising anodes for advanced rechargeable batteries due to its advantages such as high energy density, earth abundance and environmental friendly. However, its large volume change during the Li-Sn/Na-Sn alloying and de-alloying processes will result in a fast capacity degradation over a long term cycling. To solve this issue, in this work we design and synthesize a novel honeycomb-like composite composing of carbon encapsulated SnO2 nanospheres embedded in carbon film by using dual templates of SiO2 and NaCl. Using these composites as anodes both in lithium ion batteries and sodium-ion batteries, no discernable capacity degradation is observed over hundreds of long term cycles at both low current density (100 mA g-1) and high current density (500 mA g-1). Such a good cyclic stability and high delivered capacity have been attributed to the high conductivity of the supported carbon film and hollow encapsulated carbon shells, which not only provide enough space to accommodate the volume expansion but also prevent further aggregation of SnO2 nanoparticles upon cycling. By engineering electrodes of accommodating high volume expansion, we demonstrate a prototype to achieve high performance batteries, especially high-power batteries.

  10. Effects of tin concentrations on structural characteristics and electrooptical properties of tin-doped indium oxide films prepared by RF magnetron sputtering

    International Nuclear Information System (INIS)

    Yi, Choong-Hoon; Yasui, Itaru; Shigesato, Yuzo

    1995-01-01

    Structural characteristics and electrooptical properties of Sn-doped In 2 O 3 (ITO) films were investigated in terms of Sn concentrations from 5.34 to 8.99 (Sn/In at.%) with changing oxygen partial pressure and substrate temperature during deposition, in spite of using an ITO target with the same Sn concentration (7.50 SnO 2 wt%, 7.17 Sn/In at.%). The resistivity of the films deposited at 200 and 300degC had a clear tendency to decrease with decrease of the total Sn content. Sn atoms incorporated in the ITO films were classified into two types, i.e., electrically active substitutional Sn atoms contributing to carrier density and electrically nonactive impurities forming nonreducible tin-oxide complexes, which were revealed by precise lattice constant measurement. The change in the Sn concentration was found to be associated with the preferred orientation of the crystal grains, which was dominated by the deposition conditions and should reflect the crystal growth processes. (author)

  11. Enhanced Electronic Properties of SnO2 via Electron Transfer from Graphene Quantum Dots for Efficient Perovskite Solar Cells.

    Science.gov (United States)

    Xie, Jiangsheng; Huang, Kun; Yu, Xuegong; Yang, Zhengrui; Xiao, Ke; Qiang, Yaping; Zhu, Xiaodong; Xu, Lingbo; Wang, Peng; Cui, Can; Yang, Deren

    2017-09-26

    Tin dioxide (SnO 2 ) has been demonstrated as an effective electron-transporting layer (ETL) for attaining high-performance perovskite solar cells (PSCs). However, the numerous trap states in low-temperature solution processed SnO 2 will reduce the PSCs performance and result in serious hysteresis. Here, we report a strategy to improve the electronic properties in SnO 2 through a facile treatment of the films with adding a small amount of graphene quantum dots (GQDs). We demonstrate that the photogenerated electrons in GQDs can transfer to the conduction band of SnO 2 . The transferred electrons from the GQDs will effectively fill the electron traps as well as improve the conductivity of SnO 2 , which is beneficial for improving the electron extraction efficiency and reducing the recombination at the ETLs/perovskite interface. The device fabricated with SnO 2 :GQDs could reach an average power conversion efficiency (PCE) of 19.2 ± 1.0% and a highest steady-state PCE of 20.23% with very little hysteresis. Our study provides an effective way to enhance the performance of perovskite solar cells through improving the electronic properties of SnO 2 .

  12. Cauliflower-like SnO2 hollow microspheres as anode and carbon fiber as cathode for high performance quantum dot and dye-sensitized solar cells

    Science.gov (United States)

    Ganapathy, Veerappan; Kong, Eui-Hyun; Park, Yoon-Cheol; Jang, Hyun Myung; Rhee, Shi-Woo

    2014-02-01

    Cauliflower-like tin oxide (SnO2) hollow microspheres (HMS) sensitized with multilayer quantum dots (QDs) as photoanode and alternative stable, low-cost counter electrode are employed for the first time in QD-sensitized solar cells (QDSCs). Cauliflower-like SnO2 hollow spheres mainly consist of 50 nm-sized agglomerated nanoparticles; they possess a high internal surface area and light scattering in between the microspheres and shell layers. This makes them promising photoanode material for both QDSCs and dye-sensitized solar cells (DSCs). Successive ionic layer adsorption and reaction (SILAR) method and chemical bath deposition (CBD) are used for QD-sensitizing the SnO2 microspheres. Additionally, carbon-nanofiber (CNF) with a unique structure is used as an alternative counter electrode (CE) and compared with the standard platinum (Pt) CE. Their electrocatalytic properties are measured using electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and Tafel-polarization. Under 1 sun illumination, solar cells made with hollow SnO2 photoanode sandwiched with the stable CNF CE showed a power conversion efficiency of 2.5% in QDSCs and 3.0% for DSCs, which is quite promising with the standard Pt CE (QDSCs: 2.1%, and DSCs: 3.6%).Cauliflower-like tin oxide (SnO2) hollow microspheres (HMS) sensitized with multilayer quantum dots (QDs) as photoanode and alternative stable, low-cost counter electrode are employed for the first time in QD-sensitized solar cells (QDSCs). Cauliflower-like SnO2 hollow spheres mainly consist of 50 nm-sized agglomerated nanoparticles; they possess a high internal surface area and light scattering in between the microspheres and shell layers. This makes them promising photoanode material for both QDSCs and dye-sensitized solar cells (DSCs). Successive ionic layer adsorption and reaction (SILAR) method and chemical bath deposition (CBD) are used for QD-sensitizing the SnO2 microspheres. Additionally, carbon-nanofiber (CNF) with a

  13. Properties of Polydisperse Tin-doped Dysprosium and Indium Oxides

    Directory of Open Access Journals (Sweden)

    Malinovskaya Tatyana

    2017-01-01

    Full Text Available The results of investigations of the complex permittivity, diffuse-reflectance, and characteristics of crystal lattices of tin-doped indium and dysprosium oxides are presented. Using the methods of spectroscopy and X-ray diffraction analysis, it is shown that doping of indium oxide with tin results in a significant increase of the components of the indium oxide complex permittivity and an appearance of the plasma resonance in its diffuse-reflectance spectra. This indicates the appearance of charge carriers with the concentration of more than 1021 cm−3 in the materials. On the other hand, doping of the dysprosium oxide with the same amount of tin has no effect on its optical and electromagnetic properties.

  14. Synthesis, characterization and photoluminescence of tin oxide nanoribbons and nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Duraia, El-Shazly M.A., E-mail: duraia_physics@yahoo.co [Suez Canal University, Faculty of Science, Physics Department, Ismailia (Egypt); Al-Farabi Kazakh National University, Almaty (Kazakhstan); Institute of Physics and Technology, 11 Ibragimov Street, 050032 Almaty (Kazakhstan); Mansorov, Z.A. [Al-Farabi Kazakh National University, Almaty (Kazakhstan); Tokmolden, S. [Institute of Physics and Technology, 11 Ibragimov Street, 050032 Almaty (Kazakhstan)

    2009-11-15

    In this work we report the successful formation of tin oxide nanowires and tin oxide nanoribbons with high yield and by using simple cheap method. We also report the formation of curved nanoribbon, wedge-like tin oxide nanowires and star-like nanowires. The growth mechanism of these structures has been studied. Scanning electron microscope was used in the analysis and the EDX analysis showed that our samples is purely Sn and O with ratio 1:2. X-ray analysis was also used in the characterization of the tin oxide nanowire and showed the high crystallinity of our nanowires. The mechanism of the growth of our1D nanostructures is closely related to the vapor-liquid-solid (VLS) process. The photoluminescence PL measurements for the tin oxide nanowires indicated that there are three stable emission peaks centered at wavelengths 630, 565 and 395 nm. The nature of the transition may be attributed to nanocrystals inside the nanobelts or to Sn or O vacancies occurring during the growth which can induce trapped states in the band gap.

  15. Sintering of tin oxide and its applications in electronics and processing of high purity optical glasses Sinterização de óxido de estanho e sua aplicação em eletrônica e no processamento de vidros ópticos de alta pureza

    Directory of Open Access Journals (Sweden)

    J. A. Varela

    2001-06-01

    Full Text Available Tin oxide is an n type semiconductor material with a high covalent behavior. Mass transport in this oxide depends on the surface state promoted by atmosphere or by the solid solution of aliovalent oxide doping. The sintering and grain grow of this type of oxide powder is then controlled by atmosphere and by extrinsic oxygen vacancy formation. For pure SnO2 powder the surface state depends only in the interaction of atmosphere molecules with the SnO2 surface. Inert atmosphere like argon promotes oxygen vacancy formation at the surface due to the reduction of SnO 2 to SnO at surface and liberation of oxygen molecules forming an oxygen vacancy. As a consequence, surface diffusion is enhanced leading to grain coarsening, but no densification. Oxygen atmosphere inhibits the SnO2 reduction decreasing the surface oxygen vacancy concentration. Additions of dopants with lower valence at sintering temperature create extrinsic charged oxygen vacancies that promote mass transport at grain boundary leading to densification and grain growth of this polycrystalline oxide. Cobalt and niobium doped SnO2 ceramics exhibit varistor behavior, which can be applied in electronics. Moreover, SnO2 ceramics are chemically inert and can be applied in form of crucibles to melt some optical glasses.Óxido de estanho é um material semicondutor do tipo n com comportamento altamente covalente. O transporte de massa neste óxido depende do estado da superfície promovido pela atmosfera ou pela solução sólida devida a dopagem de óxido aliovalente. A sinterização e o crescimento de grão deste tipo de óxido na forma de pó é então controlado pela atmosfera e pela formação de vacância de oxigênio extrínseca. Para o pó de SnO2 puro o estado da superfície depende somente da interação das moléculas da atmosfera com a superfície do SnO2. Atmosferas inertes como a de argônio promovem a formação de vacâncias de oxigênio na superfície devido a redução de SnO2

  16. Sputtered tin oxide and titanium oxide thin films as alternative transparent conductive oxides

    Energy Technology Data Exchange (ETDEWEB)

    Boltz, Janika

    2011-12-12

    Alternative transparent conductive oxides to tin doped indium oxide have been investigated. In this work, antimony doped tin oxide and niobium doped titanium oxide have been studied with the aim to prepare transparent and conductive films. Antimony doped tin oxide and niobium doped titanium oxide belong to different groups of oxides; tin oxide is a soft oxide, while titanium oxide is a hard oxide. Both oxides are isolating materials, in case the stoichiometry is SnO{sub 2} and TiO{sub 2}. In order to achieve transparent and conductive films free carriers have to be generated by oxygen vacancies, by metal ions at interstitial positions in the crystal lattice or by cation doping with Sb or Nb, respectively. Antimony doped tin oxide and niobium doped titanium oxide films have been prepared by reactive direct current magnetron sputtering (dc MS) from metallic targets. The process parameters and the doping concentration in the films have been varied. The films have been electrically, optically and structurally analysed in order to analyse the influence of the process parameters and the doping concentration on the film properties. Post-deposition treatments of the films have been performed in order to improve the film properties. For the deposition of transparent and conductive tin oxide, the dominant parameter during the deposition is the oxygen content in the sputtering gas. The Sb incorporation as doping atoms has a minor influence on the electrical, optical and structural properties. Within a narrow oxygen content in the sputtering gas highly transparent and conductive tin oxide films have been prepared. In this study, the lowest resistivity in the as deposited state is 2.9 m{omega} cm for undoped tin oxide without any postdeposition treatment. The minimum resistivity is related to a transition to crystalline films with the stoichiometry of SnO{sub 2}. At higher oxygen content the films turn out to have a higher resistivity due to an oxygen excess. After post

  17. Sol–gel synthesis of SnO2–MgO nanoparticles and their photocatalytic activity towards methylene blue degradation

    International Nuclear Information System (INIS)

    Bayal, Nisha; Jeevanandam, P.

    2013-01-01

    Graphical abstract: - Highlights: • A simple sol–gel method for the synthesis of SnO 2 –MgO nanoparticles is reported. • Band gap of SnO 2 can be tuned by varying the magnesium content in SnO 2 –MgO. • SnO 2 –MgO shows good photocatalytic activity towards degradation of methylene blue. - Abstract: SnO 2 –MgO mixed metal oxide nanoparticles were prepared by a simple sol–gel method. The nanoparticles were characterized by power X-ray diffraction, scanning electron microscopy coupled with energy dispersive X-ray analysis, transmission electron microscopy and UV–vis diffuse reflectance spectroscopy. The XRD results indicate the formation of mixed metal oxide nanoparticles and also a decrease of SnO 2 crystallite size in the mixed metal oxide nanoparticles with increasing magnesium oxide content. The reflectance spectroscopy results show a blue shift of the band gap of SnO 2 in the mixed metal oxide nanoparticles. The photocatalytic activity of the SnO 2 –MgO nanoparticles was tested using the photodegradation of aqueous methylene blue in the presence of sunlight. The results indicate that the mixed metal oxide nanoparticles possess higher efficiency for the photodegradation of methylene blue compared to pure SnO 2 nanoparticles

  18. Effect of annealing temperature on optical properties of binary zinc tin oxide nano-composite prepared by sol-gel route using simple precursors: structural and optical studies by DRS, FT-IR, XRD, FESEM investigations.

    Science.gov (United States)

    Habibi, Mohammad Hossein; Mardani, Maryam

    2015-02-25

    Binary zinc tin oxide nano-composite was synthesized by a facile sol-gel method using simple precursors from the solutions consisting of zinc acetate, tin(IV) chloride and ethanol. Effect of annealing temperature on optical and structural properties was investigated using X-ray diffraction (XRD), diffuse reflectance spectra (DRS), field emission scanning electron microscopy (FESEM) and Fourier transform infrared spectroscopy (FTIR). XRD results revealed the existence of the ZnO and SnO2 phases. FESEM results showed that binary zinc tin oxide nano-composites ranges from 56 to 60 nm in diameter at 400°C and 500°C annealing temperatures respectively. The optical band gap was increased from 2.72 eV to 3.11 eV with the increasing of the annealing temperature. FTIR results confirmed the presence of zinc oxide and tin oxide and the broad absorption peaks at 3426 and 1602 cm(-1) can be ascribed to the vibration of absorptive water, and the absorption peaks at 546, 1038 and 1410 cm(-1) are due to the vibration of Zn-O or Sn-O groups in binary zinc tin oxide. Copyright © 2014 Elsevier B.V. All rights reserved.

  19. Multiform structures of SnO2 nanobelts

    International Nuclear Information System (INIS)

    Duan Junhong; Gong Jiangfeng; Huang Hongbo; Zhao Xiaoning; Cheng Guangxu; Yu Zhongzhen; Yang Shaoguang

    2007-01-01

    Multiform SnO 2 microstructures were synthesized by a facile thermal evaporation of tin grains. The product was characterized with a variety of techniques to obtain the structural and optical information. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images showed a large percentage of acute angle zigzag nanobelts with perfectly periodic morphology. High resolution transmission electron microscopy (HRTEM) images and selected area electron diffraction (SAED) patterns revealed that the zigzag nanobelts were single crystalline and their zone axis was along the [010] crystal direction. The growth mechanism of zigzag nanobelts was proposed based on TEM characterization and thermodynamic analysis. The zigzag nanobelts were deduced to be formed by changing the growth direction from [101-bar] to [101] or vice versa. The photoluminescence (PL) spectroscopy of the nanobelts showed a broad and strong luminescence emission centred at 550 nm

  20. Electrical Properties of Electrospun Sb-Doped Tin Oxide Nanofibers

    International Nuclear Information System (INIS)

    Leon-Brito, Neliza; Melendez, Anamaris; Ramos, Idalia; Pinto, Nicholas J; Santiago-Aviles, Jorge J

    2007-01-01

    Transparent and conducting tin oxide fibers are of considerable interest for solar energy conversion, sensors and in various electrode applications. Appropriate doping can further enhance the conductivity of the fibers without loosing optical transparency. Undoped and antimony-doped tin oxide fibers have been synthesized by our group in previous work using electrospinning and metallorganic decomposition techniques. The undoped tin oxide fibers were obtained using a mixture of pure tin oxide sol made from tin (IV) chloride : water : propanol : isopropanol at a molar ratio of 1:9:9:6, and a viscous solution made from poly(ethylene oxide) (PEO) and chloroform at a ratio of 200 mg PEO/10 mL chloroform. In this work, antimony doped fibers were obtained by adding a dopant solution of antimony trichloride and isopropanol at a ratio of 2.2812 g antimony trichloride/10 ml isopropanol to the original tin oxide precursor solution. The Sb concentration in the precursor solution is 1.5%. After deposition, the fibers were sintered 600deg. C in air for two hours. The electrical conductivity of single fibers measured at room temperature increases by up to three orders of magnitude when compared to undoped fibers prepared using the same method. The resistivity change as a function of the annealing temperature can be attributed to the thermally activated formation of a nearly stoichoimetric solid. The resistivity of the fibers changes monotonically with temperature from 714Ω-cm at 2 K to 0.1Ω-cm at 300 K. In the temperature range from 2 to 8 K the fibers have a positive magnetoresistance (MR) with the highest value of 155 % at 2 K and ±9 T. At temperatures of 10 and 12 K the sign of MR changes to negative values for low magnetic fields and positive for high magnetic fields. For higher temperatures (15 K and above) the MR becomes negative and its magnitude decreases with temperature

  1. Oxygen vacancy and Moessbauer parameters of Fe doped tin oxides

    International Nuclear Information System (INIS)

    Nomura, K.; Mudarra Navarro, A.M.; Errico, L.; Rodriguez Torres, C.E.

    2013-01-01

    It is not clear what the local environment of Fe ions included in rutile structure is. In order to clarify this point, Moessbauer parameters of 57 Fe doped SnO 2 are compared with the results of ab initio calculation taking into account different configurations of iron and oxygen vacancy in the rutile structure of SnO 2 . Calculations were performed using the LAPW+lo method (Wien2k); RMT x Kmax = 7, A mesh of 50 k-points at IBZ, 2x2x2 super cell of SnO 2 . (J.P.N.)

  2. Highly sensitive electrochemical determination of 1-naphthol based on high-index facet SnO2 modified electrode

    International Nuclear Information System (INIS)

    Huang Xiaofeng; Zhao Guohua; Liu Meichuan; Li Fengting; Qiao Junlian; Zhao Sichen

    2012-01-01

    Highlights: ► It is the first time to employ high-index faceted SnO 2 in electrochemical analysis. ► High-index faceted SnO 2 has excellent electrochemical activity toward 1-naphthol. ► Highly sensitive determination of 1-naphthol is realized on high-index faceted SnO 2 . ► The detection limit of 1-naphthol is as low as 5 nM on high-index faceted SnO 2 . ► Electro-oxidation kinetics for 1-napthol on the novel electrode is discussed. - Abstract: SnO 2 nanooctahedron with {2 2 1} high-index facet (HIF) was synthesized by a simple hydrothermal method, and was firstly employed to sensitive electrochemical sensing of a typical organic pollutant, 1-naphthol (1-NAP). The constructed HIF SnO 2 modified glassy carbon electrode (HIF SnO 2 /GCE) possessed advantages of large effective electrode area, high electron transfer rate, and low charge transfer resistance. These improved electrochemical properties allowed the high electrocatalytic performance, high effective active sites and high adsorption capacity of 1-NAP on HIF SnO 2 /GCE. Cyclic voltammetry (CV) results showed that the electrochemical oxidation of 1-NAP obeyed a two-electron transfer process and the electrode reaction was under diffusion control on HIF SnO 2 /GCE. By adopting differential pulse voltammetry (DPV), electrochemical detection of 1-NAP was conducted on HIF SnO 2 /GCE with a limit of detection as low as 5 nM, which was relatively low compared to the literatures. The electrode also illustrated good stability in comparison with those reported value. Satisfactory results were obtained with average recoveries in the range of 99.7–103.6% in the real water sample detection. A promising device for the electrochemical detection of 1-NAP with high sensitivity has therefore been provided.

  3. Photocatalytic Properties of Tin Oxide and Antimony-Doped Tin Oxide Nanoparticles

    Directory of Open Access Journals (Sweden)

    J. C. M. Brokken-Zijp

    2011-01-01

    Full Text Available For the first time it is shown that N-doped SnO2 nanoparticles photocatalyze directly the polymerization of the C=C bonds of (methacrylates under visible light illumination. These radical polymerizations also occur when these particles are doped with Sb and when the surfaces of these particles are grafted with methacrylate (MPS groups. During irradiation with visible or UV light the position and/or intensity of the plasmon band absorption of these nanoparticles are always changed, suggesting that the polymerization starts by the transfer of an electron from the conduction band of the particle to the (methacrylate C=C bond. By using illumination wavelengths with a very narrow band width we determined the influence of the incident wavelength of light, the Sb- and N-doping, and the methacrylate (MPS surface grafting on the quantum efficiencies for the initiating radical formation (Φ and on the polymer and particle network formation. The results are explained by describing the effects of Sb-doping, N-doping, and/or methacrylate surface grafting on the band gaps, energy level distributions, and surface group reactivities of these nanoparticles. N-doped (MPS grafted SnO2 (Sb ≥ 0% nanoparticles are new attractive photocatalysts under visible as well as UV illumination.

  4. Construction of SnO2?Graphene Composite with Half-Supported Cluster Structure as Anode toward Superior Lithium Storage Properties

    OpenAIRE

    Zhu, Chengling; Chen, Zhixin; Zhu, Shenmin; Li, Yao; Pan, Hui; Meng, Xin; Imtiaz, Muhammad; Zhang, Di

    2017-01-01

    Inspired by nature, herein we designed a novel construction of SnO2 anodes with an extremely high lithium storage performance. By utilizing small sheets of graphene oxide, the partitioned-pomegranate-like structure was constructed (SnO2@C@half-rGO), in which the porous clusters of SnO2 nanoparticles are partially supported by reduced graphene oxide sheets while the rest part is exposed (half-supported), like partitioned pomegranates. When served as anode for lithium-ion batteries, SnO2@C@half...

  5. Indium–tin-oxide coatings for applications in photovoltaics and displays deposited using rotary ceramic targets: Recent insights regarding process stability and doping level

    International Nuclear Information System (INIS)

    Lippens, Paul; Büchel, Michal; Chiu, David; Szepesi, Chris

    2013-01-01

    Several aspects related to high power sputtering with industrial scale sintered ceramic rotary indium–tin-oxide (ITO) targets are presented in the first part of this paper. In particular, the process stability and target integrity upon sputtering with ≥ 20 kW/m power load and the influence of the gap size between cylindrical segments are discussed. Results show that, in order to avoid nodule formation and deposition rate fluctuations, direct current (DC) power load needs to be limited well below 20 kW/m over long sputter runs. Additional work demonstrates that at a gap size at or below 0.15 mm, strongly adhering deposits form readily between cylindrical segments which are not observed with standard 0.35 mm gaps. The influence of Sn doping level on electro-optical properties of thin films targeting an application such as hetero-junction c-Si solar cells is also investigated. Again, rotary targets operated at high power (10 kW/m) are used, including standard grade ITO containing 10 wt.% SnO 2 and another composition with only 3 wt.% SnO 2 . The influence of H 2 and different concentrations of O 2 in the sputter gas is analysed for both target materials. Results indicate that although coatings derived from the lower-doped ITO exhibit considerably less absorption in the NIR due to lower carrier concentrations, their resistivity is nearly 30% higher than that from the standard ITO coating

  6. Process for Making a Noble Metal on Tin Oxide Catalyst

    Science.gov (United States)

    Davis, Patricia; Miller, Irvin; Upchurch, Billy

    2010-01-01

    To produce a noble metal-on-metal oxide catalyst on an inert, high-surface-area support material (that functions as a catalyst at approximately room temperature using chloride-free reagents), for use in a carbon dioxide laser, requires two steps: First, a commercially available, inert, high-surface-area support material (silica spheres) is coated with a thin layer of metal oxide, a monolayer equivalent. Very beneficial results have been obtained using nitric acid as an oxidizing agent because it leaves no residue. It is also helpful if the spheres are first deaerated by boiling in water to allow the entire surface to be coated. A metal, such as tin, is then dissolved in the oxidizing agent/support material mixture to yield, in the case of tin, metastannic acid. Although tin has proven especially beneficial for use in a closed-cycle CO2 laser, in general any metal with two valence states, such as most transition metals and antimony, may be used. The metastannic acid will be adsorbed onto the high-surface-area spheres, coating them. Any excess oxidizing agent is then evaporated, and the resulting metastannic acid-coated spheres are dried and calcined, whereby the metastannic acid becomes tin(IV) oxide. The second step is accomplished by preparing an aqueous mixture of the tin(IV) oxide-coated spheres, and a soluble, chloride-free salt of at least one catalyst metal. The catalyst metal may be selected from the group consisting of platinum, palladium, ruthenium, gold, and rhodium, or other platinum group metals. Extremely beneficial results have been obtained using chloride-free salts of platinum, palladium, or a combination thereof, such as tetraammineplatinum (II) hydroxide ([Pt(NH3)4] (OH)2), or tetraammine palladium nitrate ([Pd(NH3)4](NO3)2).

  7. Dual roles of a flouride-doped SnO2/TiO2 bilayer based on inverse opal/nanoparticle structure for water oxidation

    Science.gov (United States)

    Yun, Gun; Balamurugan, Maheswari; Ahn, Kwang-Soon; Lee, Sang-Kwon; Kang, Soon Hyung; Lim, Dong-Ha

    2018-01-01

    Fluorine-doped tin dioxide (FTO) inverse opals (IOs) were fabricated on a template of polystyrene (PS) beads (diameter = 400 nm (±20 nm)) by using a spin-coating method. The concentration of the FTO precursor, in particular, the 1.0 M FTO concentration solution significantly influenced the morphology of the IO film. The FTO nanoparticles upon the FTO IO film were sparsely formed relative to these formed from the 0.5 M FTO solution. To compensate for the large band gap ( E g = 3.8 eV) of FTO in the photoelectrochemical (PEC) reaction, we deposited a photoactive TiO2 shell on the FTO IO film by using the sol-gel method. The morphological change and the crystalline properties of the FTO IO and TiO2-coated FTO IO (hereafter referred to as FTO IO/TiO2) films, were investigated with field emission scanning electron microscopy and X-ray diffraction, respectively. The PEC behaviors of the samples were tested in a 0.1 M KOH solution under one sun illumination (100 mW/cm2 with an AM 1.5 filter). The highest PEC performance was obtained with the 1.0 M FTO IO/TiO2 film, which produced a photocurrent density (Jsc) of 3.28 mA/cm2 at 1.23 V (vs. normal hydrogen electrode (NHE), as briefly expressed to 1.23 VNHE) compared to 2.42 mA/cm2 at 1.23 VNHE with the 0.5 M FTO IO/TiO2 film. The approximately 30% enhanced performance of the 1.0 M FTO IO/TiO2 film was mainly attributed to the peculiar structure comprised of the FTO nanoparticle layer and IO films to form a bilayer structure, providing a much larger surface area, as well as complete coverage of the photoactive TiO2 nanoparticles through the FTO IO skeleton in the proper band alignment to boost the charge separation/transfer phenomenon, finally resulting in the enhanced PEC activity.

  8. Determination of gold and cobalt dopants in advanced materials based on tin oxide by slurry sampling high-resolution continuum source graphite furnace atomic absorption spectrometry

    Science.gov (United States)

    Filatova, Daria G.; Eskina, Vasilina V.; Baranovskaya, Vasilisa B.; Vladimirova, Svetlana A.; Gaskov, Alexander M.; Rumyantseva, Marina N.; Karpov, Yuri A.

    2018-02-01

    A novel approach is developed for the determination of Co and Au dopants in advanced materials based on tin oxide using high-resolution continuum source graphite furnace atomic absorption spectrometry (HR CS GFAAS) with direct slurry sampling. Sodium carboxylmethylcellulose (Na-CMC) is an effective stabilizer for diluted suspensions. Use Na-CMC allows to transfer the analytes into graphite furnace completely and reproducibly. The relative standard deviation obtained by HR CS GFAAS was not higher than 4%. Accuracy was proven by means inductively coupled plasma mass spectrometry (ICP-MS) in solutions after decomposition as a comparative technique. To determine Au and Co in the volume of SnO2, the acid decomposition conditions (HCl, HF) of the samples were suggested by means of an autoclave in a microwave oven.

  9. Modification of SnO2 Anodes by Atomic Layer Deposition for High Performance Lithium Ion Batteries

    KAUST Repository

    Yesibolati, Nulati

    2013-05-01

    Tin dioxide (SnO2) is considered one of the most promising anode materials for Lithium ion batteries (LIBs), due to its large theoretical capacity and natural abundance. However, its low electronic/ionic conductivities, large volume change during lithiation/delithiation and agglomeration prevent it from further commercial applications. In this thesis, we investigate modified SnO2 as a high energy density anode material for LIBs. Specifically two approaches are presented to improve battery performances. Firstly, SnO2 electrochemical performances were improved by surface modification using Atomic Layer Deposition (ALD). Ultrathin Al2O3 or HfO2 were coated on SnO2 electrodes. It was found that electrochemical performances had been enhanced after ALD deposition. In a second approach, we implemented a layer-by-layer (LBL) assembled graphene/carbon-coated hollow SnO2 spheres as anode material for LIBs. Our results indicated that the LBL assembled electrodes had high reversible lithium storage capacities even at high current densities. These superior electrochemical performances are attributed to the enhanced electronic conductivity and effective lithium diffusion, because of the interconnected graphene/carbon networks among nanoparticles of the hollow SnO2 spheres.

  10. Self-assembled 3-D flower-shaped SnO2 nanostructures with improved electrochemical performance for lithium storage

    International Nuclear Information System (INIS)

    Yang Rong; Gu Yingan; Li Yaoqi; Zheng Jie; Li Xingguo

    2010-01-01

    Flower-shaped SnO 2 nanoplates were successfully synthesized via a simple hydrothermal treatment of a mixture of tin(II) dichloride dihydrate (SnCl 2 .2H 2 O) and sodium citrate (Na 3 C 6 H 5 O 7 .2H 2 O) in alkali solution. The obtained SnO 2 nanoplates were less than 5 nm thick and self-assembled into flower-shaped nanostructures. The introduction of citrate was essential for the preparation of the SnO 2 nanoplates. The nanoscale shape and self-assembled architecture of SnO 2 nanoparticles were mainly controlled by the alkalinity of the solution. When the self-assembled SnO 2 nanostructures were used as anode materials in Li-ion batteries, they exhibit a reversible capacity of 670 mA h g -1 after 30 cycles and an average capacity fading of 0.95% per cycle after the second cycle. The good electrochemical performance of the SnO 2 sample prepared via the hydrothermal synthesis indicates the possibility of fabricating specific self-assembled three-dimensional nanostructures for Li-ion batteries.

  11. Highly conducting and transparent sprayed indium tin oxide

    Energy Technology Data Exchange (ETDEWEB)

    Rami, M.; Benamar, E.; Messaoudi, C.; Sayah, D.; Ennaoui, A. (Faculte des Sciences, Rabat (Morocco). Lab. de Physique des Materiaux)

    1998-03-01

    Indium tin oxide (ITO) has a wide range of applications in solar cells (e.g. by controlling the resistivity, we can use low conductivity ITO as buffer layer and highly conducting ITO as front contact in thin films CuInS[sub 2] and CuInSe[sub 2] based solar cells) due to its wide band gap (sufficient to be transparent) in both visible and near infrared range, and high carrier concentrations with metallic conduction. A variety of deposition techniques such as reactive electron beam evaporation, DC magnetron sputtering, evaporation, reactive thermal deposition, and spray pyrolysis have been used for the preparation of undoped and tin doped indium oxide. This latter process which makes possible the preparation of large area coatings has attracted considerable attention due to its simplicity and large scale with low cost fabrication. It has been used here to deposit highly transparent and conducting films of tin doped indium oxide onto glass substrates. The electrical, optical and structural properties have been investigated as a function of various deposition parameters namely dopant concentrations, temperature and nature of substrates. X-ray diffraction patterns have shown that deposited films are polycrystalline without second phases and have preferred orientation [400]. INdium tin oxide layers with small resistivity value around 7.10[sup -5] [omega].cm and transmission coefficient in the visible and near IR range of about 85-90% have been easily obtained. (authors) 13 refs.

  12. Chemical vapor deposition of tin oxide: fundamentals and applications

    NARCIS (Netherlands)

    Mol, A.M.B. van; Chae, Y.; McDaniel, A.H.; Allendorf, M.D.

    2006-01-01

    Tin oxide thin layers have very beneficial properties such as a high transparency for visible light and electrical conductivity making these coatings suitable for a wide variety of applications, such as solar cells, and low-emissivity coatings for architectural glass windows. Each application

  13. Mechanical Properties of Glass Surfaces Coated with Tin Oxide

    DEFF Research Database (Denmark)

    Swindlehurst, W. E.; Cantor, B.

    1978-01-01

    The effect of tin oxide coatings on the coefficient of friction and fracture strength of glass surfaces is studied. Experiments were performed partly on commercially treated glass bottles and partly on laboratory prepared microscope slides. Coatings were applied in the laboratory by decomposition...

  14. Fluorine incorporation into SnO2 nanoparticles by co-milling with polyvinylidene fluoride

    Science.gov (United States)

    Senna, Mamoru; Turianicová, Erika; Šepelák, Vladimír; Bruns, Michael; Scholz, Gudrun; Lebedkin, Sergei; Kübel, Christian; Wang, Di; Kaňuchová, Mária; Kaus, Maximilian; Hahn, Horst

    2014-04-01

    Fluorine was incorporated into SnO2 nanoparticles from polyvinylidene fluoride (PVdF) by co-milling. The incorporation process was triggered by an oxidative partial decomposition of PVdF due to the abstraction of oxygen atoms, and began soon after milling with a simultaneous decrease in the crystallite size of SnO2 from 56 nm to 19 nm, and increase in the lattice strain by a factor 7. Appearance of D and G Raman peaks indicated that the decomposition of PVdF was accompanied by the formation of nanometric carbon species. Decomposing processes of PVdF were accompanied by the continuous change in the states of F, with a decrease of C-F in PVdF and increase in Sn-F. This indicates the gradual incorporation of F into SnO2, by replacing a part of oxygen in the oxide with fluorine. These serial mechanochemical reaction processes were discussed on the basis of X-ray diffractometry, FT-IR, Raman and UV-Vis diffuse reflectance spectroscopy, transmission electron microscopy, F1s, Sn3d and C1s X-ray photoelectron spectroscopy and Auger electron spectra, as well as magic angle spinning NMR spectroscopy of 19F and 119Sn. The present findings serve as an initial stage of incorporating fluorine into SnO2 via a solvent-free solid-state process, toward the rational fabrication of fluorine doped SnO2 powders.

  15. Synthesis of chelating agent free-solid phase extractor (CAF-SPE) based on new SiO2/Al2O3/SnO2 ternary oxide and application for online preconcentration of Pb2+ coupled with FAAS

    International Nuclear Information System (INIS)

    Tarley, César R.T.; Scheel, Guilherme L.; Zappielo, Caroline D.; Suquila, Fabio A.C.; Ribeiro, Emerson S.

    2018-01-01

    A new online solid phase preconcentration method using the new SiO 2 /Al2O 3 /SnO 2 ternary oxide (designated as SiAlSn) as chelating agent free-solid phase extractor (CAF-SPE) coupled to flame atomic absorption spectrometry (FAAS) for Pb 2+ determination at trace levels in different kind of samples is proposed. The solid adsorbent has been characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDS), X-ray fluorescence spectroscopy (XRF) and textural data. The method involves the preconcentration using time-based sampling of Pb 2+ solution at pH 4.3 through 100.0 mg of packed adsorbed into a mini-column under flow rate of 4.0 mL min -1 during 5 min. The elution step was accomplished by using 1.0 mol L -1 HCl. A wide range of analytical curve (5.0-400.0 μg L -1 ), high enrichment factor (40.5), low consumption index (0.5 mL) and low limits of quantification and detection, 5.0 and 1.5 μg L -1 , respectively, were obtained with the developed method. Practical application of method was tested on water samples, chocolate powder, Ginkgo biloba and sediment (certified reference material). On the basis of the results, the SiAlSn can be considered an effective adsorbent belonging to the class of CAF-SPE for Pb 2+ determination from different matrices. (author)

  16. Texture-Etched SnO2 Glasses Applied to Silicon Thin-Film Solar Cells

    Directory of Open Access Journals (Sweden)

    Bing-Rui Wu

    2014-01-01

    Full Text Available Transparent electrodes of tin dioxide (SnO2 on glasses were further wet-etched in the diluted HCl:Cr solution to obtain larger surface roughness and better light-scattering characteristic for thin-film solar cell applications. The process parameters in terms of HCl/Cr mixture ratio, etching temperature, and etching time have been investigated. After etching process, the surface roughness, transmission haze, and sheet resistance of SnO2 glasses were measured. It was found that the etching rate was increased with the additions in etchant concentration of Cr and etching temperature. The optimum texture-etching parameters were 0.15 wt.% Cr in 49% HCl, temperature of 90°C, and time of 30 sec. Moreover, silicon thin-film solar cells with the p-i-n structure were fabricated on the textured SnO2 glasses using hot-wire chemical vapor deposition. By optimizing the texture-etching process, the cell efficiency was increased from 4.04% to 4.39%, resulting from the increment of short-circuit current density from 14.14 to 15.58 mA/cm2. This improvement in cell performances can be ascribed to the light-scattering effect induced by surface texturization of SnO2.

  17. Indium Tin Oxide Resistor-Based Nitric Oxide Microsensors

    Science.gov (United States)

    Xu, Jennifer C.; Hunter, Gary W.; Gonzalez, Jose M., III; Liu, Chung-Chiun

    2012-01-01

    A sensitive resistor-based NO microsensor, with a wide detection range and a low detection limit, has been developed. Semiconductor microfabrication techniques were used to create a sensor that has a simple, robust structure with a sensing area of 1.10 0.99 mm. A Pt interdigitated structure was used for the electrodes to maximize the sensor signal output. N-type semiconductor indium tin oxide (ITO) thin film was sputter-deposited as a sensing material on the electrode surface, and between the electrode fingers. Alumina substrate (250 m in thickness) was sequentially used for sensor fabrication. The resulting sensor was tested by applying a voltage across the two electrodes and measuring the resulting current. The sensor was tested at different concentrations of NO-containing gas at a range of temperatures. Preliminary results showed that the sensor had a relatively high sensitivity to NO at 450 C and 1 V. NO concentrations from ppm to ppb ranges were detected with the low limit of near 159 ppb. Lower NO concentrations are being tested. Two sensing mechanisms were involved in the NO gas detection at ppm level: adsorption and oxidation reactions, whereas at ppb level of NO, only one sensing mechanism of adsorption was involved. The NO microsensor has the advantages of high sensitivity, small size, simple batch fabrication, high sensor yield, low cost, and low power consumption due to its microsize. The resistor-based thin-film sensor is meant for detection of low concentrations of NO gas, mainly in the ppb or lower range, and is being developed concurrently with other sensor technology for multispecies detection. This development demonstrates that ITO is a sensitive sensing material for NO detection. It also provides crucial information for future selection of nanostructured and nanosized NO sensing materials, which are expected to be more sensitive and to consume less power.

  18. Nanocrystalline Cobalt-doped SnO2 Thin Film: A Sensitive Cigarette Smoke Sensor

    Directory of Open Access Journals (Sweden)

    Patil Shriram B.

    2011-11-01

    Full Text Available This article discusses a sensitive cigarette smoke sensor based on Cobalt doped Tin oxide (Co-SnO2 thin films deposited on glass substrate by a conventional Spray Pyrolysis technique. The Co-SnO2 thin films have been characterized by X-ray Diffraction (XRD, Scanning Electron Microscopy (SEM and Energy Dispersive X-ray Spectroscopy (EDAX. The XRD spectrum shows polycrystalline nature of the film with a mixed phase comprising of SnO2 and Co3O4. The SEM image depicts uniform granular morphology covering total substrate surface. The compositional analysis derived using EDAX confirmed presence of Co in addition to Sn and O in the film. Cigarette smoke sensing characteristics of the Co-SnO2 thin film have been studied under atmospheric condition at different temperatures and smoke concentration levels. The sensing parameters such as sensitivity, response time and recovery time are observed to be temperature dependent, exhibiting better results at 330 oC.

  19. Exploring and Controlling Intrinsic Defect Formation in SnO2 Thin Films

    KAUST Repository

    Porte, Yoann; Maller, Robert; Faber, Hendrik; Alshareef, Husam N.; Anthopoulos, Thomas D; McLachlan, Martyn

    2015-01-01

    By investigating the influence of key growth variables on the measured structural and electrical properties of SnO2 prepared by Pulsed Laser Deposition (PLD) we demonstrate fine control of intrinsic n-type defect formation. Variation of growth temperatures shows oxygen vacancies (VO) as the dominant defect which can be compensated for by thermal oxidation at temperatures > 500°C. As a consequence films with carrier concentrations in the range 1016-1019 cm-3 can be prepared by adjusting temperature alone. By altering the background oxygen pressure (PD) we observe a change in the dominant defect - from tin interstitials (Sni) at low PD (< 50 mTorr) to VO at higher oxygen pressures with similar ranges of carrier concentrations observed. Finally we demonstrate the importance of controlling the composition target surface used for PLD by exposing a target to > 100,000 laser pulses. Here carrier concentrations > 1x1020 cm-3 are observed that are attributed to high concentrations of Sni which cannot be completely compensated for by modifying the growth parameters.

  20. Exploring and Controlling Intrinsic Defect Formation in SnO2 Thin Films

    KAUST Repository

    Porte, Yoann

    2015-12-15

    By investigating the influence of key growth variables on the measured structural and electrical properties of SnO2 prepared by Pulsed Laser Deposition (PLD) we demonstrate fine control of intrinsic n-type defect formation. Variation of growth temperatures shows oxygen vacancies (VO) as the dominant defect which can be compensated for by thermal oxidation at temperatures > 500°C. As a consequence films with carrier concentrations in the range 1016-1019 cm-3 can be prepared by adjusting temperature alone. By altering the background oxygen pressure (PD) we observe a change in the dominant defect - from tin interstitials (Sni) at low PD (< 50 mTorr) to VO at higher oxygen pressures with similar ranges of carrier concentrations observed. Finally we demonstrate the importance of controlling the composition target surface used for PLD by exposing a target to > 100,000 laser pulses. Here carrier concentrations > 1x1020 cm-3 are observed that are attributed to high concentrations of Sni which cannot be completely compensated for by modifying the growth parameters.

  1. Tin oxide quantum dots embedded iron oxide composite as efficient lead sensor

    Science.gov (United States)

    Dutta, Dipa; Bahadur, Dhirendra

    2018-04-01

    SnO2 quantum dots (QDs) embedded iron oxide (IO) nanocomposite is fabricated and explored as a capable sensor for lead detection. Square wave anodic stripping voltammetry (SWASV) and amperometry have been used to explore the proposed sensor's response towards lead detection. The modified electrode shows linear current response for concentration of lead ranging from 99 nM to 6.6 µM with limit of detection 0.42 µM (34 ppb). Amperometry shows a detection limit as low as 0.18 nM (0.015 ppb); which is far below the permissible limit of lead in drinking water by World Health Organization. This proposed sensor shows linear current response (R2 = 0.98) for the lead concentration ranging from 133 × 10-9 to 4.4 × 10-6M. It also exhibits rapid response time of 12 sec with an ultra high sensitivity of 5.5 µA/nM. These detection properties promise the use of SnO2 QDs -IO composite for detection of lead in environmental sample with great ease.

  2. The improvement of gas-sensing properties of SnO2/zeolite-assembled composite

    Science.gov (United States)

    Sun, Yanhui; Wang, Jing; Li, Xiaogan; Du, Haiying; Huang, Qingpan

    2018-05-01

    SnO2-impregnated zeolite composites were used as gas-sensing materials to improve the sensitivity and selectivity of the metal oxide-based resistive-type gas sensors. Nanocrystalline MFI type zeolite (ZSM-5) was prepared by hydrothermal synthesis. Highly dispersive SnO2 nanoparticles were then successfully assembled on the surface of the ZSM-5 nanoparticles by using the impregnation methods. The SnO2 nanoparticles are nearly spherical with the particle size of 10 nm. An enhanced formaldehyde sensing of as-synthesized SnO2-ZSM-5-based sensor was observed whereas a suppression on the sensor response to other volatile organic vapors (VOCs) such as acetone, ethanol, and methanol was noticed. The possible reasons for this contrary observation were proposed to be related to the amount of the produced water vapor during the sensing reactions assisted by the ZSM-5 nanoparticles. This provides a possible new strategy to improve the selectivity of the gas sensors. The effect of the humidity on the sensor response to formaldehyde was investigated and it was found the higher humidity would decrease the sensor response. A coating layer of the ZSM-5 nanoparticles on top of the SnO2-ZSM-5-sensing film was thus applied to further improve the sensitivity and selectivity of the sensor through the strong adsorption ability to polar gases and the "filtering effect" by the pores of ZSM-5.

  3. SnO2 Nanostructure as Pollutant Gas Sensors: Synthesis, Sensing Performances, and Mechanism

    Directory of Open Access Journals (Sweden)

    Brian Yuliarto

    2015-01-01

    Full Text Available A significant amount of pollutants is produced from factories and motor vehicles in the form of gas. Their negative impact on the environment is well known; therefore detection with effective gas sensors is important as part of pollution prevention efforts. Gas sensors use a metal oxide semiconductor, specifically SnO2 nanostructures. This semiconductor is interesting and worthy of further investigation because of its many uses, for example, as lithium battery electrode, energy storage, catalyst, and transistor, and has potential as a gas sensor. In addition, there has to be a discussion of the use of SnO2 as a pollutant gas sensor especially for waste products such as CO, CO2, SO2, and NOx. In this paper, the development of the fabrication of SnO2 nanostructures synthesis will be described as it relates to the performances as pollutant gas sensors. In addition, the functionalization of SnO2 as a gas sensor is extensively discussed with respect to the theory of gas adsorption, the surface features of SnO2, the band gap theory, and electron transfer.

  4. Fabrication and excellent conductive performance of antimony-doped tin oxide-coated diatomite with porous structure

    International Nuclear Information System (INIS)

    Du Yucheng; Yan Jing; Meng Qi; Wang Jinshu; Dai Hongxing

    2012-01-01

    Graphical abstract: Antimony-doped tin oxide (ATO)-coated diatomite with porous structures are fabricated using the co-precipitation method. The porous ATO-coated diatomite material shows excellent conductive performance. Highlights: ► Sb-doped SnO 2 (ATO)-coated diatomite materials with porous structures are prepared. ► Sn/Sb ratio, ATO coating amount, pH value, and temperature influence resistivity. ► Porous ATO-coated diatomite materials show excellent conductive performance. ► The lowest resistivity of the porous ATO-coated diatomite sample is 10 Ω cm. - Abstract: Diatomite materials coated with antimony-doped tin oxide (ATO) were prepared by the co-precipitation method, and characterized by means of the techniques, such as X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, selected-area electron diffraction, X-ray fluorescence spectroscopy, and N 2 adsorption–desorption measurement. It was shown that the coated ATO possessed a tetragonal rutile crystal structure, and the ATO-coated diatomite materials had a multi-pore (micro- meso-, and macropores) architecture. The porous ATO-coated diatomite materials exhibited excellent electrical conductive behaviors. The best conductive performance (volume resistivity = 10 Ω cm) was achieved for the sample that was prepared under the conditions of Sn/Sb molar ratio = 5.2, Sn/Sb coating amount = 45 wt%, pH = 1.0, and reaction temperature = 50 °C. Such a conductive porous material is useful for the applications in physical and chemical fields.

  5. Metal-Organic Frameworks Derived Okra-like SnO2 Encapsulated in Nitrogen-Doped Graphene for Lithium Ion Battery.

    Science.gov (United States)

    Zhou, Xiangyang; Chen, Sanmei; Yang, Juan; Bai, Tao; Ren, Yongpeng; Tian, Hangyu

    2017-04-26

    A facile process is developed to prepare SnO 2 -based composites through using metal-organic frameworks (MOFs) as precursors. The nitrogen-doped graphene wrapped okra-like SnO 2 composites (SnO 2 @N-RGO) are successfully synthesized for the first time by using Sn-based metal-organic frameworks (Sn-MOF) as precursors. When utilized as an anode material for lithium-ion batteries, the SnO 2 @N-RGO composites possess a remarkably superior reversible capacity of 1041 mA h g -1 at a constant current of 200 mA g -1 after 180 charge-discharge processes and excellent rate capability. The excellent performance can be primarily ascribed to the unique structure of 1D okra-like SnO 2 in SnO 2 @N-RGO which are actually composed of a great number of SnO 2 primary crystallites and numerous well-defined internal voids, can effectively alleviate the huge volume change of SnO 2 , and facilitate the transport and storage of lithium ions. Besides, the structural stability acquires further improvement when the okra-like SnO 2 are wrapped by N-doped graphene. Similarly, this synthetic strategy can be employed to synthesize other high-capacity metal-oxide-based composites starting from various metal-organic frameworks, exhibiting promising application in novel electrode material field of lithium-ion batteries.

  6. Preparation and structural characterization of SnO2 and GeO2 methanol steam reforming thin film model catalysts by (HR)TEM

    International Nuclear Information System (INIS)

    Lorenz, Harald; Zhao Qian; Turner, Stuart; Lebedev, Oleg I.; Van Tendeloo, Gustaaf; Kloetzer, Bernhard; Rameshan, Christoph; Penner, Simon

    2010-01-01

    Structure, morphology and composition of different tin oxide and germanium oxide thin film catalysts for the methanol steam reforming (MSR) reaction have been studied by a combination of (high-resolution) transmission electron microscopy, selected area electron diffraction, dark-field imaging and electron energy-loss spectroscopy. Deposition of the thin films on NaCl(0 0 1) cleavage faces has been carried out by thermal evaporation of the respective SnO 2 and GeO 2 powders in varying oxygen partial pressures and at different substrate temperatures. Preparation of tin oxide films in high oxygen pressures (10 -1 Pa) exclusively resulted in SnO phases, at and above 473 K substrate temperature epitaxial growth of SnO on NaCl(0 0 1) leads to well-ordered films. For lower oxygen partial pressures (10 -3 to 10 -2 Pa), mixtures of SnO and β-Sn are obtained. Well-ordered SnO 2 films, as verified by electron diffraction patterns and energy-loss spectra, are only obtained after post-oxidation of SnO films at temperatures T ≥ 673 K in 10 5 Pa O 2 . Preparation of GeO x films inevitably results in amorphous films with a composition close to GeO 2 , which cannot be crystallized by annealing treatments in oxygen or hydrogen at temperatures comparable to SnO/SnO 2 . Similarities and differences to neighbouring oxides relevant for selective MSR in the third group of the periodic system (In 2 O 3 and Ga 2 O 3 ) are also discussed with the aim of cross-correlation in formation of nanomaterials, and ultimately, also catalytic properties.

  7. Enhanced thermoelectric property of oxygen deficient nickel doped SnO2 for high temperature application

    Science.gov (United States)

    Paulson, Anju; Sabeer, N. A. Muhammad; Pradyumnan, P. P.

    2018-04-01

    Motivated by the detailed investigation on the thermoelectric performance of oxide materials our work concentrated on the influence of acceptor dopants and defect density in the lattice plane for the enhancement of thermoelectric power. The series of Sn1‑x Nix O2 (0.01 ≤ x ≤ 0.05) compositions were prepared by solid state reaction mechanism and found that 3 atomic percentage Ni doped SnO2 can be considered as a good candidate due to its promising electrical and transport properties. Defect lattices were introduced in the sample and the deviation from oxygen stochiometry was ensured using photoluminescence measurement. High power factor was obtained for the 3 atomic percentage nickel doped SnO2 due to the effective number of charge carrier concentration and the depletion of oxygen rich layers. Defect centered and acceptor doped SnO2 lattice opens a new door for energy harvesting at higher temperatures.

  8. Synthesis and characterization of SnO2 doped with fluorine by the technique of polymeric precursors; Sintese e caracterizacao de SnO2 dopado com fluor pela tecnica dos precursores polimericos

    Energy Technology Data Exchange (ETDEWEB)

    Pereira, Gilberto J.; Lopes, Rafael Ialago, E-mail: gilbertop@fei.edu.br [Centro Universitario FEI, Sao Bernardo do Campo, SP (Brazil). Departamento de Engenharia de Materiais

    2016-07-01

    The present work deals with the synthesis of tin dioxide powders doped with fluorine and chlorine anions to evaluate the influence of these on the physico-chemical properties of SnO2, as well as to verify if the dopant does not make a solid solution with the material and its possible use as sintering additive. The samples were synthesized by Pechini method (polymer precursors) with tin oxalate as a source not contaminated with chlorine of this metal. Specific surface area characterization (BET method) and X-ray diffractometry (XRD) show that doping reduces the particle size of SnO2, being more effective at lower dopant levels. The dilatometry of the doped powders shows a reduction in the beginning and end temperatures of the sintering of the tin dioxide when compared with values in the literature.

  9. Effects of hydrogen gas on properties of tin-doped indium oxide films deposited by radio frequency magnetron sputtering method

    International Nuclear Information System (INIS)

    Kim, Do-Geun; Lee, Sunghun; Lee, Gun-Hwan; Kwon, Sik-Chol

    2007-01-01

    Tin-doped indium oxide (ITO) films were deposited at ∼ 70 deg. C of substrate temperature by radio frequency magnetron sputtering method using an In 2 O 3 -10% SnO 2 target. The effect of hydrogen gas ratio [H 2 / (H 2 + Ar)] on the electrical, optical and mechanical properties was investigated. With increasing the amount of hydrogen gas, the resistivity of the samples showed the lowest value of 3.5 x 10 -4 Ω.cm at the range of 0.8-1.7% of hydrogen gas ratio, while the resistivity increases over than 2.5% of hydrogen gas ratio. Hall effect measurements explained that carrier concentration and its mobility are strongly related with the resistivity of ITO films. The supplement of hydrogen gas also reduced the residual stress of ITO films up to the stress level of 110 MPa. The surface roughness and the crystallinity of the samples were investigated by using atomic force microscopy and x-ray diffraction, respectively

  10. Study of quantum dot based on tin/yttrium mixed oxide doped with terbium to be used as biomarker

    International Nuclear Information System (INIS)

    Paganini, Paula P.; Felinto, Maria Claudia F.C.; Kodaira, Claudia A.; Brito, Hermi F.; Nunes, Luiz Antonio O.

    2009-01-01

    Quantum dots (semiconductors nanocrystals) have brought a promising field to develop a new generation of luminescent biomarkers. The use of lanthanides ions as luminescent markers has many advantages, for example a security method, low cost, high specificity and also the luminescence can be promptly measured with high sensibility and accuracy. These luminescent dots are functionalized with biomolecules. For the luminophore particle to be connect with biologicals molecules (for example covalent antibody) is necessary a previous chemical treatment to modify luminophore particle surface and this process is called functionalization. A prior chemical treatment with changes on the surface luminophore particle is necessary to couple the luminophore to biological molecules. This process can be used as coating which can protect these particles from being dissolved by acid as well as provide functional groups for biological conjugation. This work presents a photoluminescence study of nanoparticles based on tin/yttrium mixed oxides doped with terbium (SnO 2 /Y 2 O 3 :Tb 3+ ), synthesized by coprecipitation method. The nanoparticles were submitted to thermal treatment and characterized by X-Ray Powder Diffraction (XRD) that showed cassiterite phase formation and the influence of thermal treatment on nanoparticles structures. These nanoparticles going to be functionalized with a natural polysaccharide (chitosan) in order to form microspheres. These microspheres going to be irradiated with gamma radiation to sterilization and it can be evaluated if the nanoparticles are resistant to irradiation and they do not lose functionality with this process. (author)

  11. Mechanical alloying of an immiscible α-Fe2O3-SnO2 ceramic

    DEFF Research Database (Denmark)

    Jiang, Jianzhong; Lin, Rong; Mørup, Steen

    1997-01-01

    in the immiscible ceramic oxide system. X-ray diffraction and Mossbauer spectroscopy investigations show that mechanical milling of alpha-Fe2O3 and SnO2 involves alloying on an atomic scale and that true solid solution formation occurs. We suggest that the high defect concentration and the chemical enthalpy of Fe3......+-O2--Sn4+ interfaces between nanostructured alpha-Fe2O3 and SnO2 regions may serve as a driving force for the formation of a solid solution in the immiscible ceramic system....

  12. Optical properties of tin oxide nanoparticles prepared by laser ablation in water: Influence of laser ablation time duration and laser fluence

    International Nuclear Information System (INIS)

    Desarkar, Himadri Sankar; Kumbhakar, P.; Mitra, A.K.

    2012-01-01

    Colloidal tin oxide nanoparticles are prepared by laser (having a wavelength of 1064 nm) ablation of tin metallic target immersed in pure deionized water. The influences of laser ablation time and laser fluence on the size and optical properties of the synthesized nanoparticles are studied. Prepared tin oxide nanoparticles are characterized by transmission electron microscope, selected area electron diffraction and UV–Visible absorption spectroscopy. The morphology of prepared tin oxide nanoparticles is found to be mostly spherical and with sizes in the nanometric range (mean radius of 3.2 to 7.3 nm). The measured UV–Visible absorption spectra show the presence of absorption peaks in the ultraviolet region. The band gap energy of samples prepared with different laser ablation time duration is calculated and is found to be increased with decrease in size (radius) of the prepared nanoparticles. Photoluminescence emission measurements at room temperature show that all the samples exhibit photoluminescence in the visible region. The peak photoluminescence emission intensity in the sample prepared with 50 min of laser ablation time is 3.5 times larger than that obtained in the sample prepared with 10 min of laser ablation time. - Highlights: ► SnO 2 nanoparticles (6.4–14.6 nm) are prepared by laser ablation in liquid technique. ► The influences of laser ablation time and laser fluence are studied. ► Samples are characterized by TEM and UV–Visible absorption spectroscopy. ► UV–Visible absorption spectra exhibit quantum confinement effect. ► Samples exhibit enhanced photoluminescence emissions in the visible region.

  13. Moessbauer effect in superconducting organosol of tin

    International Nuclear Information System (INIS)

    Dekhtyar, I.Ya.; Zhelibo, E.P.; Kushnir, B.G.; Nishchenko, M.M.; Pan, V.M.; Popov, A.G.; Khvorov, M.M.; AN Ukrainskoj SSR, Kiev. Inst. Kolloidnoj Khimii i Khimii Vody)

    1977-01-01

    Structure of disperse particles (approximately 1 μm) of tin organosols have been investigated by means of the Moessbauer effect. A considerable amount of oxides (up to 20%) in amorphous (SnO 2 ) or in metastable crystalline (SnO) states has been discovered. The observed properties of the Moessbauer spectrum of organosols are compared with measurements of their critical temperature. The effect of impurities and of other structural defects on the dynamic and superconducting properties of organosols is observed. Temperature broadening of lines and temperature variation of the Moessbauer effect value for the particle of different dimensions are in a qualitative agreement with the theory of the granular Moessbauer absorbers

  14. Synthesis and characterization of SnO2 doped with fluorine by the technique of polymeric precursors

    International Nuclear Information System (INIS)

    Pereira, Gilberto J.; Lopes, Rafael Ialago

    2016-01-01

    The present work deals with the synthesis of tin dioxide powders doped with fluorine and chlorine anions to evaluate the influence of these on the physico-chemical properties of SnO2, as well as to verify if the dopant does not make a solid solution with the material and its possible use as sintering additive. The samples were synthesized by Pechini method (polymer precursors) with tin oxalate as a source not contaminated with chlorine of this metal. Specific surface area characterization (BET method) and X-ray diffractometry (XRD) show that doping reduces the particle size of SnO2, being more effective at lower dopant levels. The dilatometry of the doped powders shows a reduction in the beginning and end temperatures of the sintering of the tin dioxide when compared with values in the literature

  15. Properties of Co-deposited indium tin oxide and zinc oxide films using a bipolar pulse power supply and a dual magnetron sputter source

    International Nuclear Information System (INIS)

    Hwang, Man-Soo; Seob Jeong, Heui; Kim, Won Mok; Seo, Yong Woon

    2003-01-01

    Multilayer coatings consisting of metal layers sandwiched between transparent conducting oxide layers are widely used for flat panel display electrodes and electromagnetic shield coatings for plasma displays, due to their high electrical conductivity and light transmittance. The electrical and optical properties of these multilayer films depend largely on the surface characteristics of the transparent conducting oxide thin films. A smoother surface on the transparent conducting oxide thin films makes it easier for the metal layer to form a continuous film, thus resulting in a higher conductivity and visible light transmittance. Indium tin oxide (ITO) and zinc oxide (ZnO) films were co-deposited using a dual magnetron sputter and a bipolar pulse power supply to decrease the surface roughness of the transparent conducting oxide films. The symmetric pulse mode of the power supply was used to simultaneously sputter an In 2 O 3 (90 wt %) : SnO 2 (10 wt %) target and a ZnO target. We varied the duty of the pulses to control the ratio of ITO : ZnO in the thin films. The electrical and optical properties of the films were studied, and special attention was paid to the surface roughness and the crystallinity of the films. By co-depositing ITO and ZnO at a pulse duty ratio of ITO:ZnO=45:45 using a dual magnetron sputter and a bipolar pulse power supply, we were able to obtain amorphous transparent conducting oxide films with a very smooth surface which had a Zn-rich buffer layer under a In-rich surface layer. All of the films exhibited typical electrical and optical properties of transparent conducting oxide films deposited at room temperature

  16. The development of latent fingerprints by zinc oxide and tin oxide nanoparticles prepared by precipitation technique

    Science.gov (United States)

    Luthra, Deepali; Kumar, Sacheen

    2018-05-01

    Fingerprints are the very important evidence at the crime scene which must be developed clearly with shortest duration of time to solve the case. Metal oxide nanoparticles could be the mean to develop the latent fingerprints. Zinc oxide and Tin Oxide Nanoparticles were prepared by using chemical precipitation technique which were dried and characterized by X-ray diffraction, UV-Visible spectroscopy and FTIR. The size of zinc oxide crystallite was found to be 14.75 nm with minimum reflectance at 360 nm whereas tin oxide have the size of 90 nm and reflectance at minimum level 321 nm. By using these powdered samples on glass, plastic and glossy cardboard, latent fingerprints were developed. Zinc oxide was found to be better candidate than tin oxide for the fingerprint development on all the three types of substrates.

  17. The effect of low platinum loading on the efficiency of PEMFC’s electrocatalysts supported on TiO2–Nb, and SnO2–Nb: An experimental comparison between active and stable conditions

    International Nuclear Information System (INIS)

    Shahgaldi, Samaneh; Hamelin, Jean

    2015-01-01

    Highlights: • SnO 2 –Nb, and TiO 2 –Nb thin films synthesized via sputtering. • SnO 2 –Nb, and TiO 2 –Nb thin films applied as a Pt support in PEMFC. • Low amount of Pt sputtered on supports as catalyst in cathode side. • Fabricate a single cell and plot I–V curves. - Abstract: Electrocatalyst supports have been demonstrated to strongly influence the cost, performance and durability of PEMFC systems, which have been among the heated research topics in the course of the past decades. However, the present support materials used in fuel cell stack are not adequately durable for commercialization. Development of active electrocatalyst with cost effectiveness and high durability is one of the main challenges. In this paper, titania and tin oxide nanoparticles doped nobidium were selected as thermo chemically stable and carbonless electrocatalyst supports. Low Pt loading (0.05 mg/cm 2 ) is deposited on supports through sputtering method, and the structure, the distribution of nanoparticles, and the electrical resistivity were systematically analyzed. To make the studies of oxygen reduction reaction activity, catalytic stability and performance of PEMFC more precise, rotation disk electrode (RDE), cyclic voltammetry (CV), and single cell test were utilized. The data analysis of this study highlighted that SnO 2 –Nb–Pt depicted higher stability and better fuel cell performance in comparison with TiO 2 –Nb–Pt

  18. Nonlinear I–V characteristics study of doped SnO2

    Indian Academy of Sciences (India)

    2016-08-26

    )–voltage () characteristics. Addition of CoO leads to creation of oxygen vacancies and helps in sintering of SnO2. Antimony oxide acts as a donor and increases the conductivity. The results are nearly the same when ...

  19. Atomic Layer Deposition of SnO2 on MXene for Li-Ion Battery Anodes

    KAUST Repository

    Ahmed, Bilal; Anjum, Dalaver H.; Gogotsi, Yury; Alshareef, Husam N.

    2017-01-01

    In this report, we show that oxide battery anodes can be grown on two-dimensional titanium carbide sheets (MXenes) by atomic layer deposition. Using this approach, we have fabricated a composite SnO2/MXene anode for Li-ion battery applications

  20. Preparation of Mesoporous SnO2 by Electrostatic Self-Assembly

    Directory of Open Access Journals (Sweden)

    Yang Jing

    2014-01-01

    Full Text Available We report a simple and scalable strategy to synthesize mesoporous SnO2 with tin dioxide nanoparticles of 5-6 nm crystalline walls and 3-4 nm pore diameter with the assistance of Mo7O246- as templating agent at room temperature. The samples were characterized by XRD, TEM, UV-DRS, XPS, and BET. The product has a moderately high surface area of 132 m2 g−1 and a narrow mesoporous structure with an average pore diameter of 3.5 nm. The photocatalytic activities of the mesoporous SnO2 were evaluated by the degradation of methyl orange (MO in aqueous solution under UV light irradiation.

  1. Characteristics of RuO2-SnO2 nanocrystalline-embedded amorphous electrode for thin film microsupercapacitors

    International Nuclear Information System (INIS)

    Kim, Han-Ki; Choi, Sun-Hee; Yoon, Young Soo; Chang, Sung-Yong; Ok, Young-Woo; Seong, Tae-Yeon

    2005-01-01

    The characteristics of RuO 2 -SnO 2 nanocrystalline-embedded amorphous electrode, grown by DC reactive sputtering, was investigated. X-ray diffraction (XRD), transmission electron microscopy (TEM), and transmission electron diffraction (TED) examination results showed that Sn and Ru metal cosputtered electrode in O 2 /Ar ambient have RuO 2 -SnO 2 nanocrystallines in an amorphous oxide matrix. It is shown that the cyclic voltammorgram (CV) result of the RuO 2 -SnO 2 nanocrystalline-embedded amorphous film in 0.5 M H 2 SO 4 liquid electrolyte is similar to a bulk-type supercapacitor behavior with a specific capacitance of 62.2 mF/cm 2 μm. This suggests that the RuO 2 -SnO 2 nanocrystalline-embedded amorphous film can be employed in hybrid all-solid state energy storage devises as an electrode of supercapacitor

  2. High Efficient Dye-Sensitized Solar Cells Based on Synthesized SnO2 Nanoparticles

    Directory of Open Access Journals (Sweden)

    W. M. N. M. B. Wanninayake

    2016-01-01

    Full Text Available In this study, SnO2 semiconductor nanoparticles were synthesized for DSC applications via acid route using tin(ii chloride as a starting material and hydrothermal method through the use of tin(iv chloride. Powder X-ray diffraction studies confirmed the formation of the rutile phase of SnO2 with nanoranged particle sizes. A quasi-solid-state electrolyte was employed instead of a conventional liquid electrolyte in order to overcome the practical limitations such as electrolyte leakage, solvent evaporation, and sealing imperfections associated with liquid electrolytes. The gel electrolytes were prepared incorporating lithium iodide (LiI and tetrapropylammonium iodide (Pr4N+I− salts, separately, into the mixture which contains polyacrylonitrile as a polymer, propylene carbonate and ethylene carbonate as plasticizers, iodide/triiodide as the redox couple, acetonitrile as the solvent, and 4-tertiary butylpyridine as an electrolyte additive. In order to overcome the recombination problem associated with the SnO2 due to its higher electron mobility, ultrathin layer of CaCO3 coating was used to cover the surface recombination sites of SnO2 nanoparticles. Maximum energy conversion efficiency of 5.04% is obtained for the device containing gel electrolyte incorporating LiI as the salt. For the same gel electrolyte, the ionic conductivity and the diffusion coefficient of the triiodide ions are 4.70 × 10−3 S cm−1 and 4.31 × 10−7 cm2 s−1, respectively.

  3. The Effect of Zeolite Composition and Grain Size on Gas Sensing Properties of SnO2/Zeolite Sensor

    Directory of Open Access Journals (Sweden)

    Yanhui Sun

    2018-01-01

    Full Text Available In order to improve the sensing properties of tin dioxide gas sensor, four kinds of different SiO2/Al2O3 ratio, different particle size of MFI type zeolites (ZSM-5 were coated on the SnO2 to prepared zeolite modified gas sensors, and the gas sensing properties were tested. The measurement results showed that the response values of ZSM-5 zeolite (SiO2/Al2O3 = 70, grain size 300 nm coated SnO2 gas sensors to formaldehyde vapor were increased, and the response to acetone decreased compared with that of SnO2 gas sensor, indicating an improved selectivity property. The other three ZSM-5 zeolites with SiO2/Al2O3 70, 150 and 470, respectively, and grain sizes all around 1 μm coated SnO2 sensors did not show much difference with SnO2 sensor for the response properties to both formaldehyde and acetone. The sensing mechanism of ZSM-5 modified sensors was briefly analyzed.

  4. Acid-catalyzed kinetics of indium tin oxide etching

    Energy Technology Data Exchange (ETDEWEB)

    Choi, Jae-Hyeok; Kim, Seong-Oh; Hilton, Diana L. [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 (Singapore); Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553 (Singapore); Cho, Nam-Joon, E-mail: njcho@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798 (Singapore); Centre for Biomimetic Sensor Science, Nanyang Technological University, 50 Nanyang Drive, 637553 (Singapore); School of Chemical and Biomedical Engineering, Nanyang Technological University, 62 Nanyang Drive, 637459 (Singapore)

    2014-08-28

    We report the kinetic characterization of indium tin oxide (ITO) film etching by chemical treatment in acidic and basic electrolytes. It was observed that film etching increased under more acidic conditions, whereas basic conditions led to minimal etching on the time scale of the experiments. Quartz crystal microbalance was employed in order to track the reaction kinetics as a function of the concentration of hydrochloric acid and accordingly solution pH. Contact angle measurements and atomic force microscopy experiments determined that acid treatment increases surface hydrophilicity and porosity. X-ray photoelectron spectroscopy experiments identified that film etching is primarily caused by dissolution of indium species. A kinetic model was developed to explain the acid-catalyzed dissolution of ITO surfaces, and showed a logarithmic relationship between the rate of dissolution and the concentration of undisassociated hydrochloric acid molecules. Taken together, the findings presented in this work verify the acid-catalyzed kinetics of ITO film dissolution by chemical treatment, and support that the corresponding chemical reactions should be accounted for in ITO film processing applications. - Highlights: • Acidic conditions promoted indium tin oxide (ITO) film etching via dissolution. • Logarithm of the dissolution rate depended linearly on the solution pH. • Acid treatment increased ITO surface hydrophilicity and porosity. • ITO film etching led to preferential dissolution of indium species over tin species.

  5. Suppression of suprathermal ions from a colloidal microjet target containing SnO2 nanoparticles by using double laser pulses

    International Nuclear Information System (INIS)

    Higashiguchi, Takeshi; Kaku, Masanori; Katto, Masahito; Kubodera, Shoichi

    2007-01-01

    We have demonstrated suppression of suprathermal ions from a colloidal microjet target plasma containing tin-dioxide (SnO 2 ) nanoparticles irradiated by double laser pulses. We observed a significant decrease of the tin and oxygen ion signals in the charged-state-separated energy spectra when double laser pulses were irradiated. The peak energy of the singly ionized tin ions decreased from 9 to 3 keV when a preplasma was produced. The decrease in the ion energy, considered as debris suppression, is attributed to the interaction between an expanding low-density preplasma and a main laser pulse

  6. Suppression of suprathermal ions from a colloidal microjet target containing SnO2 nanoparticles by using double laser pulses

    Science.gov (United States)

    Higashiguchi, Takeshi; Kaku, Masanori; Katto, Masahito; Kubodera, Shoichi

    2007-10-01

    We have demonstrated suppression of suprathermal ions from a colloidal microjet target plasma containing tin-dioxide (SnO2) nanoparticles irradiated by double laser pulses. We observed a significant decrease of the tin and oxygen ion signals in the charged-state-separated energy spectra when double laser pulses were irradiated. The peak energy of the singly ionized tin ions decreased from 9to3keV when a preplasma was produced. The decrease in the ion energy, considered as debris suppression, is attributed to the interaction between an expanding low-density preplasma and a main laser pulse.

  7. Synthesis of Stable Interfaces on SnO2 Surfaces for Charge-Transfer Applications

    Science.gov (United States)

    Benson, Michelle C.

    The commercial market for solar harvesting devices as an alternative energy source requires them to be both low-cost and efficient to replace or reduce the dependence on fossil fuel burning. Over the last few decades there has been promising efforts towards improving solar devices by using abundant and non-toxic metal oxide nanomaterials. One particular metal oxide of interest has been SnO2 due to its high electron mobility, wide-band gap, and aqueous stability. However SnO2 based solar cells have yet to reach efficiency values of other metal oxides, like TiO2. The advancement of SnO2 based devices is dependent on many factors, including improved methods of surface functionalization that can yield stable interfaces. This work explores the use of a versatile functionalization method through the use of the Cu(I)-catalyzed azide-alkyne cycloaddition (CuAAC) reaction. The CuAAC reaction is capable of producing electrochemically, photochemically, and electrocatalytically active surfaces on a variety of SnO2 materials. The resulting charge-transfer characteristics were investigated as well as an emphasis on understanding the stability of the resulting molecular linkage. We determined the CuAAC reaction is able to proceed through both azide-modified and alkyne-modified surfaces. The resulting charge-transfer properties showed that the molecular tether was capable of supporting charge separation at the interface. We also investigated the enhancement of electron injection upon the introduction of an ultra-thin ZrO2 coating on SnO2. Several complexes were used to fully understand the charge-transfer capabilities, including model systems of ferrocene and a ruthenium coordination complex, a ruthenium mononuclear water oxidation catalyst, and a commercial ruthenium based dye.

  8. Improvement of H2S Sensing Properties of SnO2-Based Thick Film Gas Sensors Promoted with MoO3 and NiO

    Directory of Open Access Journals (Sweden)

    In Sung Son

    2013-03-01

    Full Text Available The effects of the SnO2 pore size and metal oxide promoters on the sensing properties of SnO2-based thick film gas sensors were investigated to improve the detection of very low H2S concentrations (<1 ppm. SnO2 sensors and SnO2-based thick-film gas sensors promoted with NiO, ZnO, MoO3, CuO or Fe2O3 were prepared, and their sensing properties were examined in a flow system. The SnO2 materials were prepared by calcining SnO2 at 600, 800, 1,000 and 1,200 °C to give materials identified as SnO2(600, SnO2(800, SnO2(1000, and SnO2(1200, respectively. The Sn(12Mo5Ni3 sensor, which was prepared by physically mixing 5 wt% MoO3 (Mo5, 3 wt% NiO (Ni3 and SnO2(1200 with a large pore size of 312 nm, exhibited a high sensor response of approximately 75% for the detection of 1 ppm H2S at 350 °C with excellent recovery properties. Unlike the SnO2 sensors, its response was maintained during multiple cycles without deactivation. This was attributed to the promoter effect of MoO3. In particular, the Sn(12Mo5Ni3 sensor developed in this study showed twice the response of the Sn(6Mo5Ni3 sensor, which was prepared by SnO2(600 with the smaller pore size than SnO2(1200. The excellent sensor response and recovery properties of Sn(12Mo5Ni3 are believed to be due to the combined promoter effects of MoO3 and NiO and the diffusion effect of H2S as a result of the large pore size of SnO2.

  9. Facile synthesized SnO2 decorated functionalized graphene modified electrode for sensitive determination of daidzein.

    Science.gov (United States)

    Fu, Yamin; Wang, Lu; Duan, Yinghao; Zou, Lina; Ye, Baoxian

    2017-06-01

    A one-step and facile method using SnCl 2 ·H 2 O as reducing agent to reduce graphene oxide (GO) was performed in the aid of poly(diallyldimethylammonium chloride) solution (PDDA). SnCl 2 ·H 2 O is not only a reducing agent for graphene oxide (GO), but also a precursor of SnO 2 . SnO 2 -PDDA-GR composite was characterized by various surface, structural and electrochemical analysis techniques, such as transmission electron microscopy (TEM), UV spectrum (UV-vis), Infrared Spectrum (IR), X-ray diffraction (XRD), Cyclic voltammograms (CV) and electrochemical impedance (EIS). The SnO 2 -PDDA-GR composite was used to constructed electrochemical sensor (SnO 2 -PDDA-GR/GCE) for the determination of daidzein. Under the optimized experimental condition, it was found that the response of peak current is linear to the concentration of daidzein in the ranges of 2.0×10 -8 -1.0×10 -6 molL -1 , and the detection limit was estimated to be 6.7×10 -9 mol L -1 (S/N=3). Furthermore, this sensor was successfully applied for the determination of daidzein in traditional Chinese medicine (pueraria lobata) and Daidzein tablets. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Synthesis and characterization of SnO2, TiO2 and Ti0.5Sn0.5O2 nanoparticles as efficient materials for photocatalytic activity

    Science.gov (United States)

    Bargougui, R.; Pichavant, A.; Hochepied, J.-F.; Berger, M.-H.; Gadri, A.; Ammar, S.

    2016-08-01

    This work reports the synthesis of polydispersible SnO2, TiO2 and Ti0.5Sn0.5O2 nanoparticles via microwave-assisted polyol as an efficient method using diethylene glycol (DEG) and triethylene glycol (TREG) as solvent. The properties of as-prepared samples were investigated by X-ray diffractometry, transmission electron microscopy, diffuse reflectance and FTIR spectrophotometery, photoluminescence spectroscopy and N2 physisorption. The X-ray diffraction patterns of the samples were indexed on the anatase phase of TiO2 and cassiterite phase of SnO2 and Ti0.5Sn0.5O2. The TEM images show uniform isotropic morphologies with average sizes close to10 nm. The band gap is reduced for Ti0.5Sn0.5O2 and enhances visible light absorption, a shift resulting in the absorption threshold towards the visible spectral range, compared to pure titania and tin. Slight shifts to longer wavelength are attributed to the change in the acceptor's level induced by the mixture of both oxides. The evaluation of the photocatalytic activity is carried out using indigo carmine (IC) as model of chemical pollutants in UV irradiation conditions. The photocatalytic decolorization of the dye follows a pseudo-first-order kinetics and the constant apparent rate was increased with the increase of the tin oxide content up to 50%.

  11. Excimer laser processing of inkjet-printed and sputter-deposited transparent conducting SnO2:Sb for flexible electronics

    International Nuclear Information System (INIS)

    Cranton, Wayne M.; Wilson, Sharron L.; Ranson, Robert; Koutsogeorgis, Demosthenes C.; Chi Kuangnan; Hedgley, Richard; Scott, John; Lipiec, Stephen; Spiller, Andrew; Speakman, Stuart

    2007-01-01

    The feasibility of low-temperature fabrication of transparent electrode elements from thin films of antimony-doped tin oxide (SnO 2 :Sb, ATO) has been investigated via inkjet printing, rf magnetron sputtering and post-deposition excimer laser processing. Laser processing of thin films on both glass and plastic substrates was performed using a Lambda Physik 305i excimer laser, with fluences in the range 20-100 mJ cm -2 reducing sheet resistance from as-deposited values by up to 3 orders of magnitude. This is consistent with TEM analysis of the films that shows a densification of the upper 200 nm of laser-processed regions

  12. Tin( ii ) ketoacidoximates: synthesis, X-ray structures and processing to tin( ii ) oxide

    KAUST Repository

    Khanderi, Jayaprakash

    2015-10-21

    Tin(ii) ketoacidoximates of the type [HONCRCOO]Sn (R = Me 1, CHPh 2) and (MeONCMeCOO)Sn] NH·2HO 3 were synthesized by reacting pyruvate- and hydroxyl- or methoxylamine RONH (R = H, Me) with tin(ii) chloride dihydrate SnCl·2HO. The single crystal X-ray structure reveals that the geometry at the Sn atom is trigonal bipyramidal in 1, 2 and trigonal pyramidal in 3. Inter- or intramolecular hydrogen bonding is observed in 1-3. Thermogravimetric (TG) analysis shows that the decomposition of 1-3 to SnO occurs at ca. 160 °C. The evolved gas analysis during TG indicates complete loss of the oximato ligand in one step for 1 whereas a small organic residue is additionally removed at temperatures >400 °C for 2. Above 140 °C, [HONC(Me)COO]Sn (1) decomposes in air to spherical SnO particles of size 10-500 nm. Spin coating of 1 on Si or a glass substrate followed by heating at 200 °C results in a uniform film of SnO. The band gap of the produced SnO film and nanomaterial was determined by diffuse reflectance spectroscopy to be in the range of 3.0-3.3 eV. X-ray photoelectron spectroscopy indicates surface oxidation of the SnO film to SnO in ambient atmosphere.

  13. Wavelength-tuned light emission via modifying the band edge symmetry: Doped SnO2 as an example

    KAUST Repository

    Zhou, Hang

    2014-03-27

    We report the observation of ultraviolet photoluminescence and electroluminescence in indium-doped SnO2 thin films with modified "forbidden" bandgap. With increasing indium concentration in SnO 2, dominant visible light emission evolves into the ultraviolet regime in photoluminescence. Hybrid functional first-principles calculations demonstrate that the complex of indium dopant and oxygen vacancy breaks "forbidden" band gap to form allowed transition states. Furthermore, undoped and 10% indium-doped SnO2 layers are synthesized on p-type GaN substrates to obtain SnO2-based heterojunction light-emitting diodes. A dominant visible emission band is observed in the undoped SnO 2-based heterojunction, whereas strong near-ultraviolet emission peak at 398 nm is observed in the indium-doped SnO2-based heterojunction. Our results demonstrate an unprecedented doping-based approach toward tailoring the symmetry of band edge states and recovering ultraviolet light emission in wide-bandgap oxides. © 2014 American Chemical Society.

  14. Ultrasmall SnO2 Nanocrystals: Hot-bubbling Synthesis, Encapsulation in Carbon Layers and Applications in High Capacity Li-Ion Storage

    Science.gov (United States)

    Ding, Liping; He, Shulian; Miao, Shiding; Jorgensen, Matthew R.; Leubner, Susanne; Yan, Chenglin; Hickey, Stephen G.; Eychmüller, Alexander; Xu, Jinzhang; Schmidt, Oliver G.

    2014-04-01

    Ultrasmall SnO2 nanocrystals as anode materials for lithium-ion batteries (LIBs) have been synthesized by bubbling an oxidizing gas into hot surfactant solutions containing Sn-oleate complexes. Annealing of the particles in N2 carbonifies the densely packed surface capping ligands resulting in carbon encapsulated SnO2 nanoparticles (SnO2/C). Carbon encapsulation can effectively buffer the volume changes during the lithiation/delithiation process. The assembled SnO2/C thus deliver extraordinarily high reversible capacity of 908 mA.h.g-1 at 0.5 C as well as excellent cycling performance in the LIBs. This method demonstrates the great potential of SnO2/C nanoparticles for the design of high power LIBs.

  15. Ultrasmall SnO2 Nanocrystals: Hot-bubbling Synthesis, Encapsulation in Carbon Layers and Applications in High Capacity Li-Ion Storage

    Science.gov (United States)

    Ding, Liping; He, Shulian; Miao, Shiding; Jorgensen, Matthew R.; Leubner, Susanne; Yan, Chenglin; Hickey, Stephen G.; Eychmüller, Alexander; Xu, Jinzhang; Schmidt, Oliver G.

    2014-01-01

    Ultrasmall SnO2 nanocrystals as anode materials for lithium-ion batteries (LIBs) have been synthesized by bubbling an oxidizing gas into hot surfactant solutions containing Sn-oleate complexes. Annealing of the particles in N2 carbonifies the densely packed surface capping ligands resulting in carbon encapsulated SnO2 nanoparticles (SnO2/C). Carbon encapsulation can effectively buffer the volume changes during the lithiation/delithiation process. The assembled SnO2/C thus deliver extraordinarily high reversible capacity of 908 mA·h·g−1 at 0.5 C as well as excellent cycling performance in the LIBs. This method demonstrates the great potential of SnO2/C nanoparticles for the design of high power LIBs. PMID:24732294

  16. Screen printed In2O3-SnO2 nanocomposite: Structural and morphological properties and application for NO2 detection

    Directory of Open Access Journals (Sweden)

    Bessaïs B.

    2012-06-01

    Full Text Available In this work, we report on the sensing properties of screen-printed In2O3 (Indium Oxide while adding a moderate quantity of SnO2. It was found that the addition of SnO2 improves the response and decreases the operating temperature of the sensitive element for NO2 detection. However, a non-controlled amount of SnO2 leads to opposite result; for this reason in the present investigation we test films with different composition in order to optimize the quantity of SnO2 to be added. The crystallinity, roughness and morphology of the obtained In2O3-SnO2 anocomposite were analyzed using X-ray Diffraction (XRD, Transmission Electronic Microscopy (TEM and Atomic Force Microscopy (AFM. The atomic composition of the In2O3-SnO2 films was determined with the energy dispersive spectroscopy (EDX analysis during TEM observations. The effect of the composition on the cristallinity and morphological properties of the films was analyzed. Finally, the In2O3-SnO2 films were tested like sensitive elements for NO2 detection, wherein the effect of the composition was correlated with the sensor response in NO2 ambient. It was found that the addition of a moderate quantity of SnO2 to In2O3 exhibited high sensitivity at rather lower operating temperatures.

  17. Distinction between SnO2 nanoparticles synthesized using co ...

    Indian Academy of Sciences (India)

    Administrator

    pared with that of a co-precipitation-modified SnO2 nanoparticles. Keywords. SnO2 nanoparticle ... Dye-sensitized solar cells (DSSCs), which convert light to electricity by means of ... nature, additives and aging time. Nanosized particles pre-.

  18. Rf reactive sputtering of indium-tin-oxide films

    International Nuclear Information System (INIS)

    Tvarozek, V.; Novotny, I.; Harman, R.; Kovac, J.

    1986-01-01

    Films of indium-tin-oxide (ITO) have been deposited by rf reactive diode sputtering of metallic InSn alloy targets, or ceramic ITO targets, in an Ar and Ar+0 2 atmosphere. Electrical as well as optical properties of ITO films were controlled by varying sputtering parameters and by post-deposition heat-treatment in Ar, H 2 , N 2 , H 2 +N 2 ambients. The ITO films exhibited low resistivity approx. 2 x 10 -4 Ω cm, high transmittance approx. 90% in the visible spectral region and high reflectance approx. 80% in the near infra-red region. (author)

  19. Pretreatment of Platinum/Tin Oxide-Catalyst

    Science.gov (United States)

    Hess, Robert V.; Paulin, Patricia A.; Miller, Irvin M.; Schryer, David R.; Sidney, Barry D.; Wood, George M.; Upchurch, Billy T.; Brown, Kenneth G.

    1987-01-01

    Addition of CO to He pretreatment doubles catalytic activity. In sealed, high-energy, pulsed CO2 laser, CO and O2 form as decomposition products of CO2 in laser discharge zone. Products must be recombined, because oxygen concentration of more than few tenths of percent causes rapid deterioration of power, ending in unstable operation. Promising low-temperature catalyst for combining CO and O2 is platinum on tin oxide. New development increases activity of catalyst so less needed for recombination process.

  20. Reactivation of a tin oxide-containing catalyst

    Science.gov (United States)

    Upchurch, Billy T. (Inventor); Miller, Irvin M. (Inventor); Brown, Kenneth G. (Inventor); Hess, Robert V. (Inventor); Schryer, David R. (Inventor); Sidney, Barry D. (Inventor); Wood, George M. (Inventor); Paulin, Patricia A. (Inventor)

    1989-01-01

    A method for the reactivation of a tin oxide-containing catalyst of a CO.sub.2 laser is provided. First, the catalyst is pretreated by a standard procedure. When the catalyst experiences diminished activity during usage, the heated zone surrounding the catalyst is raised to a temperature which is the operating temperature of the laser and 400.degree. C. for approximately one hour. The catalyst is exposed to the same laser gas mixture during this period. The temperature of the heated zone is then lowered to the operating temperature of the CO.sub.2 laser.

  1. Low-temperature Synthesis of Tin(II) Oxide From Tin(II) ketoacidoximate Precursor

    KAUST Repository

    Alshankiti, Buthainah

    2015-04-01

    Sn (II) oxide finds numerous applications in different fields such as thin film transistors1, solar cells2 and sensors.3 In this study we present the fabrication of tin monoxide SnO by using Sn (II) ketoacid oximate complexes as precursors. Tin (II) ketoacidoximates of the type [HON=CRCOO]2Sn where R= Me 1, R= CH2Ph 2, and [(MeON=CMeCOO)3Sn]- NH4 +.2H2O 3 were synthesized by in situ formation of the ketoacid oximate ligand. The crystal structures were determined via single crystal X- ray diffraction of the complexes 1-3 revealed square planar and square pyramidal coordination environments for the Sn atom. Intramolecular hydrogen bonding is observed in all the complexes. Furthermore, the complexes were characterized by Infrared (IR), Nuclear Magnetic Resonance (NMR) and elemental analysis. From thermogravimetric analysis of 1-3, it was found that the complexes decomposed in the range of 160 – 165 oC. Analysis of the gases evolved during decomposition indicated complete loss of the oximato ligand in one step and the formation of SnO. Spin coating of 1 on silicon or glass substrate show uniform coating of SnO. Band gaps of SnO films were measured and found to be in the range of 3.0 – 3.3 eV by UV-Vis spectroscopy. X-ray photoelectron spectroscopy indicated surface oxidation of the SnO film. Heating 1 above 140 oC in air gives SnO of size ranging from 10 – 500 nm and is spherical in shape. The SnO nanomaterial is characterized by powder X-ray diffraction(XRD), Raman spectroscopy, Scanning Electron Microscopy (SEM), and Transmission Electron Microscopy (TEM).

  2. Tunable SnO2 Nanoribbon by Electric Fields and Hydrogen Passivation

    Directory of Open Access Journals (Sweden)

    Xin-Lian Chen

    2017-01-01

    Full Text Available Under external transverse electronic fields and hydrogen passivation, the electronic structure and band gap of tin dioxide nanoribbons (SnO2NRs with both zigzag and armchair shaped edges are studied by using the first-principles projector augmented wave (PAW potential with the density function theory (DFT framework. The results showed that the electronic structures of zigzag and armchair edge SnO2NRs exhibit an indirect semiconducting nature and the band gaps demonstrate a remarkable reduction with the increase of external transverse electronic field intensity, which demonstrate a giant Stark effect. The value of the critical electric field for bare Z-SnO2NRs is smaller than A-SnO2NRs. In addition, the different hydrogen passivation nanoribbons (Z-SnO2NRs-2H and A-SnO2NRs-OH show different band gaps and a slightly weaker Stark effect. The band gap of A-SnO2NRs-OH obviously is enhanced while the Z-SnO2NRs-2H reduce. Interestingly, the Z-SnO2NRs-OH presented the convert of metal-semiconductor-metal under external transverse electronic fields. In the end, the electronic transport properties of the different edges SnO2NRs are studied. These findings provide useful ways in nanomaterial design and band engineering for spintronics.

  3. Tin Oxide Nanorod Array-Based Electrochemical Hydrogen Peroxide Biosensor

    Directory of Open Access Journals (Sweden)

    Liu Jinping

    2010-01-01

    Full Text Available Abstract SnO2 nanorod array grown directly on alloy substrate has been employed as the working electrode of H2O2 biosensor. Single-crystalline SnO2 nanorods provide not only low isoelectric point and enough void spaces for facile horseradish peroxidase (HRP immobilization but also numerous conductive channels for electron transport to and from current collector; thus, leading to direct electrochemistry of HRP. The nanorod array-based biosensor demonstrates high H2O2 sensing performance in terms of excellent sensitivity (379 μA mM−1 cm−2, low detection limit (0.2 μM and high selectivity with the apparent Michaelis–Menten constant estimated to be as small as 33.9 μM. Our work further demonstrates the advantages of ordered array architecture in electrochemical device application and sheds light on the construction of other high-performance enzymatic biosensors.

  4. Application of least squares support vector regression and linear multiple regression for modeling removal of methyl orange onto tin oxide nanoparticles loaded on activated carbon and activated carbon prepared from Pistacia atlantica wood.

    Science.gov (United States)

    Ghaedi, M; Rahimi, Mahmoud Reza; Ghaedi, A M; Tyagi, Inderjeet; Agarwal, Shilpi; Gupta, Vinod Kumar

    2016-01-01

    Two novel and eco friendly adsorbents namely tin oxide nanoparticles loaded on activated carbon (SnO2-NP-AC) and activated carbon prepared from wood tree Pistacia atlantica (AC-PAW) were used for the rapid removal and fast adsorption of methyl orange (MO) from the aqueous phase. The dependency of MO removal with various adsorption influential parameters was well modeled and optimized using multiple linear regressions (MLR) and least squares support vector regression (LSSVR). The optimal parameters for the LSSVR model were found based on γ value of 0.76 and σ(2) of 0.15. For testing the data set, the mean square error (MSE) values of 0.0010 and the coefficient of determination (R(2)) values of 0.976 were obtained for LSSVR model, and the MSE value of 0.0037 and the R(2) value of 0.897 were obtained for the MLR model. The adsorption equilibrium and kinetic data was found to be well fitted and in good agreement with Langmuir isotherm model and second-order equation and intra-particle diffusion models respectively. The small amount of the proposed SnO2-NP-AC and AC-PAW (0.015 g and 0.08 g) is applicable for successful rapid removal of methyl orange (>95%). The maximum adsorption capacity for SnO2-NP-AC and AC-PAW was 250 mg g(-1) and 125 mg g(-1) respectively. Copyright © 2015 Elsevier Inc. All rights reserved.

  5. Hydrothermal self-assembly of novel porous flower-like SnO_2 architecture and its application in ethanol sensor

    International Nuclear Information System (INIS)

    Jiang, X.H.; Ma, S.Y.; Sun, A.M.; Zhang, Z.M.; Jin, W.X.; Wang, T.T.; Li, W.Q.; Xu, X.L.; Luo, J.; Cheng, L.; Mao, Y.Z.; Zhang, M.

    2015-01-01

    Graphical abstract: - Highlights: • We have fabricated porous SnO_2 nanoflowers using a simple hydrothermal route. • The sensitivity of porous SnO_2 nanoflowers is about 208 for 500 ppm ethanol at 300 °C. • The porous SnO_2 nanoflowers could be a good candidate for fabricating effective ethanol sensor. - Abstract: Different morphologies of tin dioxide (SnO_2) architectures were prepared by increasing reaction time (12, 18, 24 and 48 h) under a facile hydrothermal process and followed by calcination. The crystal structures and morphologies of the hierarchical architecture were characterized in detail by means of powder X-ray diffraction (XRD), energy dispersive X-ray detector (EDX), scanning electron microscope (SEM) and transmission electron microscope (TEM). The results showed that the porous flower-like SnO_2 architecture was obtained by 24 h hydrotherm treatment. Most importantly, the sensors based on porous flower-like SnO_2 architecture exhibited perfect sensing performance toward ethanol with excellent selectivity, high response and fast response-recovery capability compared with other SnO_2 nanoflowers for the same ethanol concentration at 300 °C. The response value was about 208 and the response-recovery time was around 8 and 7 s for 500 ppm ethanol, respectively. The enhancement in gas sensing properties was attributed to the unique structures, including the flower-like structure and porous feature, which provided more gas active center and diffusion pathways. The results indicated that porous flower-like SnO_2 architecture was a potential candidate for fabricating effective ethanol sensor. Furthermore, the possible growth mechanism and the ethanol sensing mechanism of the architecture were discussed, too.

  6. Indium tin oxide films prepared via wet chemical route

    International Nuclear Information System (INIS)

    Legnani, C.; Lima, S.A.M.; Oliveira, H.H.S.; Quirino, W.G.; Machado, R.; Santos, R.M.B.; Davolos, M.R.; Achete, C.A.; Cremona, M.

    2007-01-01

    In this work, indium tin oxide (ITO) films were prepared using a wet chemical route, the Pechini method. This consists of a polyesterification reaction between an α-hydroxicarboxylate complex (indium citrate and tin citrate) with a polyalcohol (ethylene glycol) followed by a post annealing at 500 deg. C. A 10 at.% of doping of Sn 4+ ions into an In 2 O 3 matrix was successfully achieved through this method. In order to characterize the structure, the morphology as well as the optical and electrical properties of the produced ITO films, they were analyzed using different experimental techniques. The obtained films are highly transparent, exhibiting transmittance of about 85% at 550 nm. They are crystalline with a preferred orientation of [222]. Microscopy discloses that the films are composed of grains of 30 nm average size and 0.63 nm RMS roughness. The films' measured resistivity, mobility and charge carrier concentration were 5.8 x 10 -3 Ω cm, 2.9 cm 2 /V s and - 3.5 x 10 20 /cm 3 , respectively. While the low mobility value can be related to the small grain size, the charge carrier concentration value can be explained in terms of the high oxygen concentration level resulting from the thermal treatment process performed in air. The experimental conditions are being refined to improve the electrical characteristics of the films while good optical, chemical, structural and morphological qualities already achieved are maintained

  7. Layered tin dioxide microrods

    International Nuclear Information System (INIS)

    Duan Junhong; Huang Hongbo; Gong Jiangfeng; Zhao Xiaoning; Cheng Guangxu; Yang Shaoguang

    2007-01-01

    Single-crystalline layered SnO 2 microrods were synthesized by a simple tin-water reaction at 900 deg. C. The structural and optical properties of the sample were characterized by x-ray powder diffraction, energy-dispersive x-ray spectroscopy, scanning electron microscopy, high resolution transmission electron microscopy, Raman scattering and photoluminescence (PL) spectroscopy. High resolution transmission electron microscopy studies and selected area electron diffraction patterns revealed that the layered SnO 2 microrods are single crystalline and their growth direction is along [1 1 0]. The growth mechanism of the microrods was proposed based on SEM, TEM characterization and thermodynamic analysis. It is deduced that the layered microrods grow by the stacking of SnO 2 sheets with a (1 1 0) surface in a vapour-liquid-solid process. Three emission peaks at 523, 569 and 626 nm were detected in room-temperature PL measurements

  8. Incorporation of sol-gel SnO2:Sb into nanoporous SiO2

    International Nuclear Information System (INIS)

    Canut, B.; Blanchin, M.G.; Ramos-Canut, S.; Teodorescu, V.; Toulemonde, M.

    2006-01-01

    Silicon oxide films thermally grown on Si(1 0 0) wafers were irradiated with 200 MeV 197 Au ions in the 10 9 -10 1 cm -2 fluence range. The targets were then etched at room temperature in aqueous HF solution (1 vol.%) for various durations. Atomic force microscopy (AFM) in the tapping mode was used to probe the processed surfaces. Conical holes with a low size dispersion were evidenced. Their surface diameter varies between 20 and 70 nm, depending on the etching time. Sol-gel dip coating technique, associated with a further annealing treatment performed at 500 o C for 15 min, was used to fill the nanopores created in SiO 2 with a transparent conductive oxide (SnO 2 doped with antimony). Transmission electron microscopy (TEM) performed on cross-sectional specimen showed that SnO 2 :Sb crystallites of ∼5 nm mean size are trapped in the holes without degrading their geometry

  9. Confined SnO2 quantum-dot clusters in graphene sheets as high-performance anodes for lithium-ion batteries

    OpenAIRE

    Zhu, Chengling; Zhu, Shenmin; Zhang, Kai; Hui, Zeyu; Pan, Hui; Chen, Zhixin; Li, Yao; Zhang, Di; Wang, Da-Wei

    2016-01-01

    Construction of metal oxide nanoparticles as anodes is of special interest for next-generation lithium-ion batteries. The main challenge lies in their rapid capacity fading caused by the structural degradation and instability of solid-electrolyte interphase (SEI) layer during charge/discharge process. Herein, we address these problems by constructing a novel-structured SnO2-based anode. The novel structure consists of mesoporous clusters of SnO2 quantum dots (SnO2 QDs), which are wrapped with...

  10. Indium tin oxide surface smoothing by gas cluster ion beam

    CERN Document Server

    Song, J H; Choi, W K

    2002-01-01

    CO sub 2 cluster ions are irradiated at the acceleration voltage of 25 kV to remove hillocks on indium tin oxide (ITO) surfaces and thus to attain highly smooth surfaces. CO sub 2 monomer ions are also bombarded on the ITO surfaces at the same acceleration voltage to compare sputtering phenomena. From the atomic force microscope results, the irradiation of monomer ions makes the hillocks sharper and the surfaces rougher from 1.31 to 1.6 nm in roughness. On the other hand, the irradiation of CO sub 2 cluster ions reduces the height of hillocks and planarize the ITO surfaces as smooth as 0.92 nm in roughness. This discrepancy could be explained by large lateral sputtering yield of the cluster ions and re-deposition of sputtered particles by the impact of the cluster ions on surfaces.

  11. Genotoxicity of indium tin oxide by comet test

    Directory of Open Access Journals (Sweden)

    İbrahim Hakkı Ciğerci

    2015-06-01

    Full Text Available Indium tin oxide (ITO is used for liquid crystal display (LCDs, electrochromic displays, flat panel displays, field emission displays, touch or laptop computer screens, cell phones, energy conserving architectural windows, defogging aircraft and automobile windows, heat-reflecting coatings to increase light bulb efficiency, gas sensors, antistatic window coatings, wear resistant layers on glass, nanowires and nanorods because of its unique properties of high electrical conductivity, transparency and mechanical resistance.Genotoxic effects of ITO were investigated on the root cells of Allium cepa by Comet assay. A. cepa roots were treated with the aqueous dispersions of ITO at 5 different concentrations (12.5, 25, 50, 75, and 100 ppm for 4 h. A significant increase in DNA damage was a observed at all concentrations of ITO by Comet assay. These result indicate that ITO exhibit genotoxic activity in A. cepa root meristematic cells.

  12. Gas Sensing Properties of Indium Tin Oxide Nanofibers

    Directory of Open Access Journals (Sweden)

    Shiyou Xu

    2009-11-01

    Full Text Available Indium Tin Oxide (ITO nanofibers were fabricated by the electrospinning process. The morphology and crystal structure of ITO nanofibers were studied by SEM, XRD, and TEM respectively. The results showed that polycrystalline ITO nanofibers with an average diameter of 80 nm were obtained. Sensors based on these nanofibers were fabricated by collecting these nanofibers on the integrated sensor platforms. The ITO nanofiber-based sensors showed very fast and high sensor responses at both room and elevated temperatures for NO2. The ratios of resistance in NO2 over that in air were 5 at room temperature and 34 at the optimal working temperature, respectively. The ITO nanofiber-based sensor can be repeatedly used. The details for the fast, enhanced sensor responses and the optimal temperature were discussed.

  13. Selectivity of Catalytically Modified Tin Dioxide to CO and NH3 Gas Mixtures

    Directory of Open Access Journals (Sweden)

    Artem Marikutsa

    2015-10-01

    Full Text Available This paper is aimed at selectivity investigation of gas sensors, based on chemically modified nanocrystalline tin dioxide in the detection of CO and ammonia mixtures in air. Sol-gel prepared tin dioxide was modified by palladium and ruthenium oxides clusters via an impregnation technique. Sensing behavior to CO, NH3 and their mixtures in air was studied by in situ resistance measurements. Using the appropriate match of operating temperatures, it was shown that the reducing gases mixed in a ppm-level with air could be discriminated by the noble metal oxide-modified SnO2. Introducing palladium oxide provided high CO-sensitivity at 25–50 °C. Tin dioxide modified by ruthenium oxide demonstrated increased sensor signals to ammonia at 150–200 °C, and selectivity to NH3 in presence of higher CO concentrations.

  14. Three-Dimensional Graphene/Single-Walled Carbon Nanotube Aerogel Anchored with SnO2 Nanoparticles for High Performance Lithium Storage.

    Science.gov (United States)

    Wang, Jing; Fang, Fang; Yuan, Tao; Yang, Junhe; Chen, Liang; Yao, Chi; Zheng, Shiyou; Sun, Dalin

    2017-02-01

    A unique 3D graphene-single walled carbon nanotube (G-SWNT) aerogel anchored with SnO 2 nanoparticles (SnO 2 @G-SWCNT) is fabricated by the hydrothermal self-assembly process. The influences of mass ratio of SWCNT to graphene on structure and electrochemical properties of SnO 2 @G-SWCNT are investigated systematically. The SnO 2 @G-SWCNT composites show excellent electrochemical performance in Li-ion batteries; for instance, at a current density of 100 mA g -1 , a specific capacity of 758 mAh g -1 was obtained for the SnO 2 @G-SWCNT with 50% SWCNT in G-SWCNT and the Coulombic efficiency is close to 100% after 200 cycles; even at current density of 1 A g -1 , it can still maintain a stable specific capacity of 537 mAh g -1 after 300 cycles. It is believed that the 3D G-SWNT architecture provides a flexible conductive matrix for loading the SnO 2 , facilitating the electronic and ionic transportation and mitigating the volume variation of the SnO 2 during lithiation/delithiation. This work also provides a facile and reasonable strategy to solve the pulverization and agglomeration problem of other transition metal oxides as electrode materials.

  15. Application of pristine and doped SnO2 nanoparticles as a matrix for agro-hazardous material (organophosphate) detection

    Science.gov (United States)

    Khan, Naushad; Athar, Taimur; Fouad, H.; Umar, Ahmad; Ansari, Z. A.; Ansari, S. G.

    2017-02-01

    With an increasing focus on applied research, series of single/composite materials are being investigated for device development to detect several hazardous, dangerous, and toxic molecules. Here, we report a preliminary attempt of an electrochemical sensor fabricated using pristine Ni and Cr-doped nano tin oxide material (SnO2) as a tool to detect agro-hazardous material, i.e. Organophosphate (OP, chlorpyrifos). The nanomaterial was synthesized using the solution method. Nickel and chromium were used as dopant during synthesis. The synthesized material was calcined at 1000 °C and characterized for morphological, structural, and elemental analysis that showed the formation of agglomerated nanosized particles of crystalline nature. Screen-printed films of powder obtained were used as a matrix for working electrodes in a cyclic voltammogram (CV) at various concentrations of organophosphates (0.01 to 100 ppm). The CV curves were obtained before and after the immobilization of acetylcholinesterase (AChE) on the nanomaterial matrix. An interference study was also conducted with hydroquinone to ascertain the selectivity. The preliminary study indicated that such material can be used as suitable matrix for a device that can easily detect OP to a level of 10 ppb and thus contributes to progress in terms of desired device technology for the food and agricultural-industries.

  16. A simple method to deposit palladium doped SnO2 thin films using plasma enhanced chemical vapor deposition technique

    International Nuclear Information System (INIS)

    Kim, Young Soon; Wahab, Rizwan; Shin, Hyung-Shik; Ansari, S. G.; Ansari, Z. A.

    2010-01-01

    This work presents a simple method to deposit palladium doped tin oxide (SnO 2 ) thin films using modified plasma enhanced chemical vapor deposition as a function of deposition temperature at a radio frequency plasma power of 150 W. Stannic chloride (SnCl 4 ) was used as precursor and oxygen (O 2 , 100 SCCM) (SCCM denotes cubic centimeter per minute at STP) as reactant gas. Palladium hexafluroacetyleacetonate (Pd(C 5 HF 6 O 2 ) 2 ) was used as a precursor for palladium. Fine granular morphology was observed with tetragonal rutile structure. A peak related to Pd 2 Sn is observed, whose intensity increases slightly with deposition temperature. Electrical resistivity value decreased from 8.6 to 0.9 mΩ cm as a function of deposition temperature from 400 to 600 deg. C. Photoelectron peaks related to Sn 3d, Sn 3p3, Sn 4d, O 1s, and C 1s were detected with varying intensities as a function of deposition temperature.

  17. Cauliflower hillock formation through crystallite migration of SnO2 thin films prepared on alumina substrates by using MOCVD

    International Nuclear Information System (INIS)

    Choi, Gwangpyo; Ryu, Hyunwook; Lee, Woosun; Hong, Kwangjun; Shin, Dongcharn; Park, Jinseong; Seo, Yongjin; Akbar, Sheikh A.

    2003-01-01

    Tin-oxide thin films were deposited at 375 .deg. C on α-alumina substrates by using metalorganic chemical vapor deposition (MOCVD) process. A number of hillocks were formed on the film after annealing in air at 500 .deg. C for 30 min, but fewer hillocks were formed for annealing in N 2 . The hillocks on the film and the grains on the alumina substrate were composed of crystallites. The oxygen content and the binding energy after annealing in air came to close to values for the stoichiometric SnO 2 . There was no relationship between the film thickness and the binding energy shift, but the binding energy did change with the annealing atmosphere and the oxygen content. The cauliflower hillocks on the film seem to be formed by the continuous migration of crystallites from cauliflower grains on the substrate to release the stress due to the increased oxygen content and volume. A cauliflower hillock can be grown by continuous migration of crystallites from nearby grains to the hillock.

  18. Study of tin amalgam mirrors by "1"1"9Sn Mössbauer spectroscopy and other analytical methods

    International Nuclear Information System (INIS)

    Lerf, A.; Wagner, F. E.; Herrera, L. K.; Justo, A.; Mu noz-Páez, A.; Pérez-Rodríguez, J. L.

    2016-01-01

    From the beginning of the 16 "t"h until the end of the 19 "t"h century the most widely used mirrors consisted of a pane of glass backed with a reflecting layer of tin-mercury amalgam. They were made by sliding the glass pane over a tin foil covered with liquid mercury. After removal of the superfluous mercury, tin amalgam formed slowly at ambient temperature and yielded a reflecting layer adhering to the surface of the glass. Such mirrors often deteriorate in the course of time by oxidation of the tin in the amalgam to stannous or stannic oxide. "1"1"9Sn Mössbauer spectroscopy, scanning electron microscopy, micro-XRF and X-ray diffraction have been used to study this deterioration process. The studied specimens were a modern mirror made for the reconstruction of the Green Vault in Dresden in the early 2000s, two rather well preserved German mirrors from the 17 "t"h and 19 "t"h centuries and several strongly deteriorated specimens of Baroque mirrors from the south of Spain. The modern mirror consists mainly of a Sn_0_._9Hg_0_._1 amalgam with only 2 % of SnO_2. The older German mirrors showed more pronounced oxidation, containing 12 and 15 % of SnO_2, which did not noticeably impair their reflectivity. In the samples from the Spanish mirrors at best a few percent of metallic phase was left. The majority of the tin had oxidised to SnO_2, but between 8 and 20 % of the tin was present as SnO. X-ray diffraction yielded similar results and micro-XRF mapping using synchrotron radiation for excitation gave information on the distribution of Sn and Hg in the reflecting layer of the mirrors.

  19. The acidic properties of mixed tin and antimony oxide catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Irving, E.A.; Taylor, D.

    1978-01-01

    The acidic properties of mixed tin + antimony oxide catalysts were studied in the isomerization of 3,3-dimethyl-1-butene, cyclopropane, 1-butene, and cis-2-butene and the dehydration of isopropanol over the mixed oxides outgassed at room temperature and 698/sup 0/K. Only the zero-order portions of the reaction were used for calculations. With catalysts outgassed at room temperature, weakly acidic sites were present, and all the reactions probably occurred by a carbonium ion mechanism with Broensted acid sites as a source of protons. The rates increased with increasing antimony content to a maximum at approx. 50 at. % and then decreased with further increase in the antimony content. Outgassing of the catalysts at 698/sup 0/K increased the isomerization rate of 3,3-dimethyl-1-butene, but decreased those for cyclopropane and isopropanol due to poisoning by the propylene produced. For 1-butene and cis-2-butene and catalysts outgassed at 698/sup 0/K, only catalysts with less than 50Vertical Bar3< antimony were active. The catalysts were poisoned by treatment with bases or with sodium acetate. A proposed correlation between rates and acidity led to the conclusion that the catalyst composition corresponding to maximum acidity differs from that for maximum selective oxidation activity. Graphs and 10 references.

  20. Atomic structure of the SnO2 (110) surface

    International Nuclear Information System (INIS)

    Godin, T.J.; LaFemina, J.P.

    1991-12-01

    Using a tight-binding, total-energy model, we examine atomic relaxations of the ideal stoichiometric and reduced tin oxide (11) surfaces. In both cases we find a nearly bond-length conserving rumple of the top layer, and a smaller counter-relaxation of the second layer. These calculations show no evidence of surface states in the band gap for either surface

  1. Indium--tin oxide films radio frequency sputtered from specially formulated high density indium--tin oxide targets

    International Nuclear Information System (INIS)

    Kulkarni, S.; Bayard, M.

    1991-01-01

    High density ITO (indium--tin oxide) targets doped with Al 2 O 3 and SiO 2 manufactured in the Tektronix Ceramics Division have been used to rf sputter ITO films of various thicknesses on borosilicate glass substrates. Sputtering in an oxygen--argon gas mixture and annealing in forming gas, resulted in ITO films exhibiting 90% transmission at 550 nm and a sheet resistance of 15 Ω/sq for a thickness of 1100 A. Sputtering in an oxygen--argon gas mixture and annealing in air increased sheet resistance without a large effect on the transmission. Films sputtered in argon gas alone were transparent in the visible and the sheet resistance was found to be 100--180 Ω/sq for the same thickness, without annealing

  2. Kinetics of plasma oxidation of germanium-tin (GeSn)

    Science.gov (United States)

    Wang, Wei; Lei, Dian; Dong, Yuan; Zhang, Zheng; Pan, Jisheng; Gong, Xiao; Tok, Eng-Soon; Yeo, Yee-Chia

    2017-12-01

    The kinetics of plasma oxidation of GeSn at low temperature is investigated. The oxidation process is described by a power-law model where the oxidation rate decreases rapidly from the initial oxidation rate with increasing time. The oxidation rate of GeSn is higher than that of pure Ge, which can be explained by the higher chemical reaction rate at the GeSn-oxide/GeSn interface. In addition, the Sn atoms at the interface region exchange positions with the underlying Ge atoms during oxidation, leading to a SnO2-rich oxide near the interface. The bandgap of GeSn oxide is extracted to be 5.1 ± 0.2 eV by XPS, and the valence band offset at the GeSn-oxide/GeSn heterojunction is found to be 3.7 ± 0.2 eV. Controlled annealing experiments demonstrate that the GeSn oxide is stable with respect to annealing temperatures up to 400 °C. However, after annealing at 450 °C, the GeO2 is converted to GeO, and desorbs from the GeSn-oxide/GeSn, leaving behind Sn oxide.

  3. Synthesis and electrochemical properties of tin oxide-based composite by rheological technique

    International Nuclear Information System (INIS)

    He Zeqiang; Li Xinhai; Xiong Lizhi; Wu Xianming; Xiao Zhuobing; Ma Mingyou

    2005-01-01

    Novel rheological technique was developed to synthesize tin oxide-based composites. The microstructure, morphology, and electrochemical performance of the materials were investigated by X-ray diffraction, scanning electron microscopy and electrochemical methods. The particles of tin oxide-based materials form an inactive matrix. The average size of the particles is about 150 nm. The material delivers a charge capacity of more than 570 mAh g -1 . The capacity loss per cycle is about 0.15% after being cycled 30 times. The good electrochemical performance indicates that this kind of tin oxide-based material is promising anode for lithium-ion battery

  4. Colloid electrostatic self-assembly synthesis of SnO2/graphene nanocomposite for supercapacitors

    Science.gov (United States)

    Wang, Yankun; Liu, Yushan; Zhang, Jianmin

    2015-10-01

    In this paper, a simple and fast colloid electrostatic self-assembly method was adopted to prepare the SnO2/graphene nanocomposite (SGNC). The crystal structure, chemical composition, and porous property of composite were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, Raman microscopy, X-ray photoelectron spectroscopy (XPS), and N2 adsorption-desorption experiments. The morphology analyses showed that the SnO2 nanoparticles about 5 nm were distributed homogenously on the reduced graphene oxide (rGO) sheets surface. The electrochemical performance measurements exhibited that SGNC possessed the specific capacitance of 347.3 F g-1 at a scan rate of 5 mV s-1 in 1 M Na2SO4 electrolyte solution. Furthermore, this material also showed excellent cycling stability, and the specific capacitance still retained 90 % after 3000 cycles. These results indicate that the SGNC is a promising electrode material for high-performance supercapacitors.

  5. Promotion effect of Pt on a SnO2-WO3 material for NOx sensing

    Science.gov (United States)

    Wang, Chen-Yang; Hong, Zih-Siou; Wu, Ren-Jang

    2015-05-01

    Metal-oxide nanocomposites were prepared over screen-printed gold electrodes to be used as room-temperature NOx (nitric-oxide (NO) and nitrogen dioxide (NO2)) sensors. Various weight ratios of SnO2-WO3 and Pt loadings were used for NO sensing. The sensing materials were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM) and BET surface analysis. The NO-sensing results indicated that SnO2-WO3 (1:2) was more effective than other materials were. The sensor response (S=resistance of N2/resistance of NO=RN2/RNO) for detecting 1000 ppm of NO at room temperature was 2.6. The response time (T90) and recovery time (TR90) was 40 s and 86 s, respectively. By further loading with 0.5% Pt, the sensor response increased to 3.3. The response and recovery times of 0.5% Pt/SnO2-WO3 (1:2) were 40 s and 206 s, respectively. The linearity of the sensor response for a NO concentration range of 10-1000 ppm was 0.9729. A mechanism involving Pt promotion of the SnO2-WO3 heterojunction was proposed for NO adsorption, surface reaction, and adsorbed NO2 desorption.

  6. Facile coating of manganese oxide on tin oxide nanowires with high-performance capacitive behavior.

    Science.gov (United States)

    Yan, Jian; Khoo, Eugene; Sumboja, Afriyanti; Lee, Pooi See

    2010-07-27

    In this paper, a very simple solution-based method is employed to coat amorphous MnO2 onto crystalline SnO2 nanowires grown on stainless steel substrate, which utilizes the better electronic conductivity of SnO2 nanowires as the supporting backbone to deposit MnO2 for supercapacitor electrodes. Cyclic voltammetry (CV) and galvanostatic charge/discharge methods have been carried out to study the capacitive properties of the SnO2/MnO2 composites. A specific capacitance (based on MnO2) as high as 637 F g(-1) is obtained at a scan rate of 2 mV s(-1) (800 F g(-1) at a current density of 1 A g(-1)) in 1 M Na2SO4 aqueous solution. The energy density and power density measured at 50 A g(-1) are 35.4 W h kg(-1) and 25 kW kg(-1), respectively, demonstrating the good rate capability. In addition, the SnO2/MnO2 composite electrode shows excellent long-term cyclic stability (less than 1.2% decrease of the specific capacitance is observed after 2000 CV cycles). The temperature-dependent capacitive behavior is also discussed. Such high-performance capacitive behavior indicates that the SnO2/MnO2 composite is a very promising electrode material for fabricating supercapacitors.

  7. Piper Ornatum and Piper Betle as Organic Dyes for TiO2 and SnO2 Dye Sensitized Solar Cells

    Science.gov (United States)

    Hayat, Azwar; Putra, A. Erwin E.; Amaliyah, Novriany; Hayase, Shuzi; Pandey, Shyam. S.

    2018-03-01

    Dye sensitized solar cell (DSSC) mimics the principle of natural photosynthesis are now currently investigated due to low manufacturing cost as compared to silicon based solar cells. In this report, we utilized Piper ornatum (PO) and Piper betle (PB) as sensitizer to fabricate low cost DSSCs. We compared the photovoltaic performance of both sensitizers with Titanium dioxide (TiO2) and Tin dioxide (SnO2) semiconductors. The results show that PO and PB dyes have higher Short circuit current (Jsc) when applied in SnO2 compared to standard TiO2 photo-anode film even though the Open circuit voltage (Voc) was hampered on SnO2 device. In conclusion, from the result, higher electron injections can be achieved by choosing appropriate semiconductors with band gap that match with dyes energy level as one of strategy for further low cost solar cell.

  8. Wavelength-tuned light emission via modifying the band edge symmetry: Doped SnO2 as an example

    KAUST Repository

    Zhou, Hang; Deng, Rui; Li, Yongfeng; Yao, Bin; Ding, Zhanhui; Wang, Qingxiao; Han, Yu; Wu, Tao; Liu, Lei

    2014-01-01

    at 398 nm is observed in the indium-doped SnO2-based heterojunction. Our results demonstrate an unprecedented doping-based approach toward tailoring the symmetry of band edge states and recovering ultraviolet light emission in wide-bandgap oxides. © 2014

  9. Effects of laser-induced recovery process on conductive property of SnO2:F thin films

    International Nuclear Information System (INIS)

    Chen, Ming-Fei; Lin, Keh-moh; Ho, Yu-Sen

    2011-01-01

    In this study, we developed a laser annealing process to enhance the electrical properties of SnO 2 :F (FTO) films. It is already known that in contrast to indium oxides or zinc oxides, the carrier mobility of FTO films is relatively lower. Thus, improving the mobility is a direct way to enhance the conductivity of FTO films. Furthermore, improving the crystal quality of the thin films is in turn a direct way to enhance the mobility effectively. Contrary to the high working temperatures of traditional annealing processes, the laser annealing process, with its focusing character, enables us to modify the crystal quality of oxide films on substrates with low-melting points. Using a self-built laser system, which consists of a Nd:YAG solid-state laser with a wavelength of 1064 nm and a beam shaper lens, we carried out a series of experiments to achieve the optimal laser annealing process. Hall, SEM, and XRD measurements were used to characterize the opto-electrical as well as the structural properties. As experimental results show, the tin oxide crystallites recovered well during the laser annealing process. By using a suitable beam profile and a proper laser intensity, the film resistivity was reduced from 7.19 ± 0.55 x 10 -3 Ω cm to 6.70 ± 0.20 x 10 -3 Ω cm while the carrier mobility was enhanced from 11.18 ± 0.29 cm 2 /V s to 11.71 ± 0.34 cm 2 /V s.

  10. Synthesis of antimony-doped tin oxide (ATO) nanoparticles by the nitrate-citrate combustion method

    International Nuclear Information System (INIS)

    Zhang Jianrong; Gao Lian

    2004-01-01

    Antimony-doped tin oxide (ATO) nanoparticles having rutile structure have been synthesized by the combustion method using citric acid (CA) as fuel and nitrate as an oxidant, the metal sources were granulated tin and Sb 2 O 3 . The influence of citric acid (fuel) to metal ratio on the average crystallite size, specific surface area and morphology of the nanoparticles has been investigated. X-ray diffraction showed the tin ions were reduced to elemental tin during combustion reaction. The average ATO crystallite size increased with the increase of citric acid (fuel). Powder morphology and the comparison of crystallite size and grain size shows that the degree of agglomeration of the powder decreased with an increase of the ratio. The highest specific surface area was 37.5 m 2 /g when the citric acid to tin ratio was about 6

  11. Thermal behavior of the amorphous precursors of the ZrO2-SnO2 system

    International Nuclear Information System (INIS)

    Stefanic, Goran; Music, Svetozar; Ivanda, Mile

    2008-01-01

    Thermal behavior of the amorphous precursors of the ZrO 2 -SnO 2 system on the ZrO 2 -rich side of the concentration range, prepared by co-precipitation from aqueous solutions of the corresponding salts, was monitored using differential thermal analysis, X-ray powder diffraction, Raman spectroscopy, field emission scanning electron microscopy (FE-SEM) and energy dispersive X-ray spectrometry (EDS). The crystallization temperature of the amorphous precursors increased with an increase in the SnO 2 content, from 405 deg. C (0 mol% SnO 2 ) to 500 deg. C (40 mol% SnO 2 ). Maximum solubility of Sn 4+ ions in the ZrO 2 lattice (∼25 mol%) occurred in the metastable products obtained upon crystallization of the amorphous precursors. A precise determination of unit-cell parameters, using both Rietveld and Le Bail refinements of the powder diffraction patterns, shows that the incorporation of Sn 4+ ions causes an asymmetric distortion of the monoclinic ZrO 2 lattice. The results of phase analysis indicate that the incorporation of Sn 4+ ions has no influence on the stabilization of cubic ZrO 2 and negligible influence on the stabilization of tetragonal ZrO 2 . Partial stabilization of tetragonal ZrO 2 in products having a tin content above its solid-solubility limit was attributed to the influence of ZrO 2 -SnO 2 surface interactions. In addition to phases closely structurally related to cassiterite, monoclinic ZrO 2 and tetragonal ZrO 2 , a small amount of metastable ZrSnO 4 phase appeared in the crystallization products of samples with 40 and 50 mol% of SnO 2 calcined at 1000 deg. C. Further temperature treatments caused a decrease in and disappearance of metastable phases. The results of the micro-structural analysis show that the sinterability of the crystallization products significantly decreases with an increase in the SnO 2 content

  12. 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%.

  13. Study on preparation of SnO2-TiO2/Nano-graphite composite anode and electro-catalytic degradation of ceftriaxone sodium.

    Science.gov (United States)

    Guo, Xiaolei; Wan, Jiafeng; Yu, Xiujuan; Lin, Yuhui

    2016-12-01

    In order to improve the electro-catalytic activity and catalytic reaction rate of graphite-like material, Tin dioxide-Titanium dioxide/Nano-graphite (SnO 2 -TiO 2 /Nano-G) composite was synthesized by a sol-gel method and SnO 2 -TiO 2 /Nano-G electrode was prepared in hot-press approach. The composite was characterized by X-ray photoelectron spectroscopy, fourier transform infrared, Raman, N 2 adsorption-desorption, scanning electrons microscopy, transmission electron microscopy and X-ray diffraction. The electrochemical performance of the SnO 2 -TiO 2 /Nano-G anode electrode was investigated via cyclic voltammetry and electrochemical impedance spectroscopy. The electro-catalytic performance was evaluated by the degradation of ceftriaxone sodium and the yield of ·OH radicals in the reaction system. The results demonstrated that TiO 2 , SnO 2 and Nano-G were composited successfully, and TiO 2 and SnO 2 particles dispersed on the surface and interlamination of the Nano-G uniformly. The specific surface area of SnO 2 modified anode was higher than that of TiO 2 /Nano-G anode and the degradation rate of ceftriaxone sodium within 120 min on SnO 2 -TiO 2 /Nano-G electrode was 98.7% at applied bias of 2.0 V. The highly efficient electro-chemical property of SnO 2 -TiO 2 /Nano-G electrode was attributed to the admirable conductive property of the Nano-G and SnO 2 -TiO 2 /Nano-G electrode. Moreover, the contribution of reactive species ·OH was detected, indicating the considerable electro-catalytic activity of SnO 2 -TiO 2 /Nano-G electrode. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Surface characterization of sol–gel derived indium tin oxide films on ...

    Indian Academy of Sciences (India)

    Unknown

    , India ... 1. Introduction. Indium tin oxide (ITO) coating on glass is an important item in the field ..... In addition, contamination of carbon from environment cannot be ruled ..... processing of ceramics, glasses and composites (eds) L L. Hench and ...

  15. On the deposition parameters of indium oxide (IO) and tin oxide (TO) by reactive evaporation technique

    International Nuclear Information System (INIS)

    Hassan, F.; Abdullah, A.H.; Salam, R.

    1990-01-01

    Thin films of tin oxide (TO) and indium oxide (IO) are prepared by the reactive evaporation technique, where indium or tin sources are evaporated and made to react with oxygen gas injected close to the substrate. In both depositions a substrate temperature of 380 0 C and a chamber pressure of 2x10 -5 mbar are utilized, but however different oxygen flow rates has been maintained. For TO, the deposition rate is found to be constant up to about 55 minutes of deposition time with a deposition rate of about 0.10 A/s, but for longer deposition time the deposition rate increases rapidly up to about 0.30 A/s. The IO displays a higher deposition rate of about 0.80 A/s over a deposition time 30 minutes, beyond which the deposition rate increases gradually

  16. Photoacoustic spectroscopy investigation of sintered zinc-tin-oxide ceramics

    Directory of Open Access Journals (Sweden)

    Ivetić Tamara B.

    2007-01-01

    Full Text Available In this paper the changes that occurred in differently activated ZnO-SnO2 and sintered samples were investigated using photoacoustic spectroscopy. ZnO and SnO2 powders, mixed in the molar ratio 2:1, were mechanically activated in a planetary ball mill for 10-160 min. The mixtures were pres­sed and isothermally sintered at 1300°C for two hours. X-ray diffraction analysis of the obtained sintered samples was performed in order to investigate changes of the phase composition and confirmed only the presence of a pure zinc stannate (Zn2SnO4 phase in all the sintered samples as a result of the solid state reaction and reaction sintering between the starting ZnO and SnO2 powders. The microstructure of the sintered sam­ples was examined by scanning electron microscopy and showed that mechanical activation leads to the formation of a structure with reduced particle size which accelerates spinel formation. Grain growth of the spinel phase slows down the densification process and together with the agglomerates formed during mechanical activation causes the appearance of a porous microstructure. The photoacoustic (PA phase and amplitude spectra of the sintered samples were recorded as a function of the chopped frequency of the laser beam used (red laser with a power of 25 mW, λ=632 nm in a thermal-transmission detection configuration. PA experimental data were analyzed using the Rosenzweig-Gersho thermal-piston model, which enabled determination of the thermal diffusivity, ZT (m2s-1, diffusion coefficient of the minority free carriers D (m2s-1 and the optical absorption coefficient (m-1. The detected differences of the measured thermal-electrical properties of the obtained Zn2SnO4 ceramics indicate changes in the material induced by the different preparation procedure of the starting powders before the sintering process.

  17. Fabrication of heterojunction solar cells by improved tin oxide deposition on insulating layer

    Science.gov (United States)

    Feng, Tom; Ghosh, Amal K.

    1980-01-01

    Highly efficient tin oxide-silicon heterojunction solar cells are prepared by heating a silicon substrate, having an insulating layer thereon, to provide a substrate temperature in the range of about 300.degree. C. to about 400.degree. C. and thereafter spraying the so-heated substrate with a solution of tin tetrachloride in a organic ester boiling below about 250.degree. C. Preferably the insulating layer is naturally grown silicon oxide layer.

  18. Polycrystalline Mn-alloyed indium tin oxide films

    International Nuclear Information System (INIS)

    Scarlat, Camelia; Schmidt, Heidemarie; Xu, Qingyu; Vinnichenko, Mykola; Kolitsch, Andreas; Helm, Manfred; Iacomi, Felicia

    2008-01-01

    Magnetic ITO films are interesting for integrating ITO into magneto-optoelectronic devices. We investigated n-conducting indium tin oxide (ITO) films with different Mn doping concentration which have been grown by chemical vapour deposition using targets with the atomic ratio In:Sn:Mn=122:12:0,114:12:7, and 109:12:13. The average film roughness ranges between 30 and 50 nm and XRD patterns revealed a polycrystalline structure. Magnetotransport measurements revealed negative magnetoresistance for all the samples, but high field positive MR can be clearly observed at 5 K with increasing Mn doping concentration. Spectroscopic ellipsometry (SE) has been used to prove the existence of midgap states in the Mn-alloyed ITO films revealing a transmittance less than 80%. A reasonable model for the ca. 250 nm thick Mn-alloyed ITO films has been developed to extract optical constants from SE data below 3 eV. Depending on the Mn content, a Lorentz oscillator placed between 1 and 2 eV was used to model optical absorption below the band gap

  19. Surface energy for electroluminescent polymers and indium-tin-oxide

    International Nuclear Information System (INIS)

    Zhong Zhiyou; Yin Sheng; Liu Chen; Zhong Youxin; Zhang Wuxing; Shi Dufang; Wang Chang'an

    2003-01-01

    The contact angles on the thin films of poly[2-methoxy-5-(2'-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and indium-tin-oxide (ITO) were measured by the sessile-drop technique. The surface energies of the films were calculated using the Owens-Wendt (OW) and van Oss-Chaudhury-Good (vOCG) approaches. The overall total surface energies of MEH-PPV and the as-received ITO were 30.75 and 30.07 mJ/m 2 , respectively. Both approaches yielded almost the same surface energies. The surface energies were mainly contributed from the dispersion interactions or Lifshitz-van der Waals (LW) interactions for both MEH-PPV and ITO. The changes in the contact angles and surface energies of the ITO films, due to different solvent cleaning processes and oxygen plasma treatments, were analyzed. Experimental results revealed that the total surface energy of the ITO films increased after various cleaning processes. In comparison with different solvents used in this study, we found that methanol is an effective solvent for ITO cleaning, as a higher surface energy was observed. ITO films treated with oxygen plasma showed the highest surface energy. This work demonstrated that contact angle measurement is a useful method to diagnose the cleaning effect on ITO films

  20. Investigation of hyperfine parameters of semiconductor oxides SnO2 and TiO2 pure and doped with 3d transition methods using spectroscopy of perturbed gamma-gamma angular correlation

    International Nuclear Information System (INIS)

    Schell, Juliana

    2015-01-01

    This study aimed the use of nuclear technique Perturbed γ-γ Angular Correlation Spectroscopy (PAC) to measure the hyperfine interactions in thin films and powder samples of SnO 2 and TiO 2 pure and doped with transition metals to obtain a systematic investigation of defects and magnetism from an atomic point of view with the main motivation the application in spintronics. The work also focused on the preparation and characterization of samples by conventional techniques such as X-ray diffraction, scanning electron microscopy, energy dispersive spectroscopy and magnetization measurements. Pure samples of the films were measured by the systematic variation of thermal treatment and applied magnetic field. These measurements were performed in HISKP at the University of Bonn (Rheinische Friedrich-Wilhelms-Universität Bonn) using 111 In( 111 Cd) or 181 Hf ( 181 Ta); at IPEN, in turn, these measurements were performed after the diffusion of the same probe nuclei. Another part of PAC measurements were carried out using 111 mCd( 111 Cd) and 117 Cd ( 117 In) in Isotope Mass Separator On-Line (ISOLDE) at Centre Européen Recherche Nucléaire (CERN). The measurements were performed from 8 K to 1173 K. After comparing results from macroscopic techniques with those from PAC, it was concluded that there is a correlation between the defects, magnetism and the mobility of charge carriers in semiconductors studied here. A step forward in the search for semiconductors, whose magnetic ordering allows its use in electronics based on spin. Some results have been published, including results obtained at the University of Bonn for the sandwich doctorate period [1-7]. (author)

  1. Ultraviolet photodetectors made from SnO2 nanowires

    International Nuclear Information System (INIS)

    Wu, Jyh-Ming; Kuo, Cheng-Hsiang

    2009-01-01

    SnO 2 nanowires can be synthesized on alumina substrates and formed into an ultraviolet (UV) photodetector. The photoelectric current of the SnO 2 nanowires exhibited a rapid photo-response as a UV lamp was switched on and off. The ratio of UV-exposed current to dark current has been investigated. The SnO 2 nanowires were synthesized by a vapor-liquid-solid process at a temperature of 900 o C. It was found that the nanowires were around 70-100 nm in diameter and several hundred microns in length. High-resolution transmission electron microscopy (HRTEM) image indicated that the nanowires grew along the [200] axis as a single crystallinity. Cathodoluminescence (CL), thin-film X-ray diffractometry, and X-ray photoelectron spectroscopy (XPS) were used to characterize the as-synthesized nanowires.

  2. SnO2 thin-films prepared by a spray-gel pyrolysis: Influence of sol properties on film morphologies

    International Nuclear Information System (INIS)

    Luyo, Clemente; Fabregas, Ismael; Reyes, L.; Solis, Jose L.; Rodriguez, Juan; Estrada, Walter; Candal, Roberto J.

    2007-01-01

    Nanostructured tin oxide films were prepared by depositing different sols using the so-called spray-gel pyrolysis process. SnO 2 suspensions (sols) were obtained from tin (IV) tert-amyloxide (Sn(t-OAm) 4 ) or tin (IV) chloride pentahydrate (SnCl 4 .5H 2 O) precursors, and stabilized with ammonia or tetraethylammonium hydroxide (TEA-OH). Xerogels from the different sols were obtained by solvent evaporation under controlled humidity. The Relative Gelling Volumes (RGV) of these sols strongly depended on the type of precursor. Xerogels obtained from inorganic salts gelled faster, while, as determined by thermal gravimetric analysis, occluding a significant amount of volatile compounds. Infrared spectroscopic analysis was performed on raw and annealed xerogels (300, 500 deg. C, 1 h). Annealing removed water and ammonium or alkyl ammonium chloride, increasing the number of Sn-O-Sn bonds. SnO 2 films were prepared by spraying the sols for 60 min onto glass and alumina substrates at 130 deg. C. The films obtained from all the sols were amorphous or displayed a very small grain size, and crystallized after annealing at 400 deg. C or 500 deg. C in air for 2 h. X-ray diffraction analysis showed the presence of the cassiterite structure and line broadening indicated a polycrystalline material with a grain size in the nanometer range. Results obtained from Scanning Electron Microscopy analysis demonstrated a strong dependence of the film morphology on the RGV of the sols. Films obtained from Sn(t-OAm) 4 showed a highly textured morphology based on fiber-shape bridges, whereas the films obtained from SnCl 4 .5H 2 O had a smoother surface formed by 'O-ring' shaped domains. Lastly, the performance of these films as gas sensor devices was tested. The conductance (sensor) response for ethanol as a target analyte was of the same order of magnitude for the three kinds of films. However, the response of the highly textured films was more stable with shorter response times

  3. Evolución de la morfología y facetaje de nanoestructuras de SnO2 crecidas por pirólisis en fase aerosol sobre sustratos de vidrio

    Directory of Open Access Journals (Sweden)

    Morante, J. R.

    2004-04-01

    Full Text Available Nanostructural characteristics of polycrystalline SnO2 thin films determine their psychical and chemical properties as semiconductor gas sensor. Tin oxide thin films obtained by spray pyrolysis deposition on glass substrates have been studied (35nm - 300nm. We have studied the influence of the pyrolysis temperature (300ºC - 530ºC on the crystallographic structure of the films. These samples have been characterised by X-ray diffraction, and high-resolution transmission electron microscopy. Some atomic models of growing have been proposed, with a double pyramidal structure and rhombic base.Las características nanoestructurales de las capas finas policristalinas de SnO2 determinan sus propiedades físicas y químicas como material sensor de gas. Se han analizado un conjunto de muestras (35nm - 300nm crecidas por pirólisis en fase aerosol sobre substratos de vidrio, estudiando la influencia de la temperatura de pirólisis (375ºC - 530ºC en la estructura cristalina de las capas. Estas muestras han sido caracterizadas mediante difracción de rayos X y microscopia electrónica de transmisión de alta resolución. Se han propuesto modelos atómicos de crecimiento, de estructura doble piramidal truncada y base rómbica, para las diferentes temperaturas de depósito.

  4. Atomic layer epitaxy of hematite on indium tin oxide for application in solar energy conversion

    Science.gov (United States)

    Martinson, Alex B.; Riha, Shannon; Guo, Peijun; Emery, Jonathan D.

    2016-07-12

    A method to provide an article of manufacture of iron oxide on indium tin oxide for solar energy conversion. An atomic layer epitaxy method is used to deposit an uncommon bixbytite-phase iron (III) oxide (.beta.-Fe.sub.2O.sub.3) which is deposited at low temperatures to provide 99% phase pure .beta.-Fe.sub.2O.sub.3 thin films on indium tin oxide. Subsequent annealing produces pure .alpha.-Fe.sub.2O.sub.3 with well-defined epitaxy via a topotactic transition. These highly crystalline films in the ultra thin film limit enable high efficiency photoelectrochemical chemical water splitting.

  5. Designed hybrid nanostructure with catalytic effect: beyond the theoretical capacity of SnO2 anode material for lithium ion batteries.

    Science.gov (United States)

    Wang, Ye; Huang, Zhi Xiang; Shi, Yumeng; Wong, Jen It; Ding, Meng; Yang, Hui Ying

    2015-03-17

    Transition metal cobalt (Co) nanoparticle was designed as catalyst to promote the conversion reaction of Sn to SnO2 during the delithiation process which is deemed as an irreversible reaction. The designed nanocomposite, named as SnO2/Co3O4/reduced-graphene-oxide (rGO), was synthesized by a simple two-step method composed of hydrothermal (1(st) step) and solvothermal (2(nd) step) synthesis processes. Compared to the pristine SnO2/rGO and SnO2/Co3O4 electrodes, SnO2/Co3O4/rGO nanocomposites exhibit significantly enhanced electrochemical performance as the anode material of lithium-ion batteries (LIBs). The SnO2/Co3O4/rGO nanocomposites can deliver high specific capacities of 1038 and 712 mAh g(-1) at the current densities of 100 and 1000 mA g(-1), respectively. In addition, the SnO2/Co3O4/rGO nanocomposites also exhibit 641 mAh g(-1) at a high current density of 1000 mA g(-1) after 900 cycles, indicating an ultra-long cycling stability under high current density. Through ex-situ TEM analysis, the excellent electrochemical performance was attributed to the catalytic effect of Co nanoparticles to promote the conversion of Sn to SnO2 and the decomposition of Li2O during the delithiation process. Based on the results, herein we propose a new method in employing the catalyst to increase the capacity of alloying-dealloying type anode material to beyond its theoretical value and enhance the electrochemical performance.

  6. Designed hybrid nanostructure with catalytic effect: beyond the theoretical capacity of SnO2 anode material for lithium ion batteries

    Science.gov (United States)

    Wang, Ye; Huang, Zhi Xiang; Shi, Yumeng; Wong, Jen It; Ding, Meng; Yang, Hui Ying

    2015-01-01

    Transition metal cobalt (Co) nanoparticle was designed as catalyst to promote the conversion reaction of Sn to SnO2 during the delithiation process which is deemed as an irreversible reaction. The designed nanocomposite, named as SnO2/Co3O4/reduced-graphene-oxide (rGO), was synthesized by a simple two-step method composed of hydrothermal (1st step) and solvothermal (2nd step) synthesis processes. Compared to the pristine SnO2/rGO and SnO2/Co3O4 electrodes, SnO2/Co3O4/rGO nanocomposites exhibit significantly enhanced electrochemical performance as the anode material of lithium-ion batteries (LIBs). The SnO2/Co3O4/rGO nanocomposites can deliver high specific capacities of 1038 and 712 mAh g−1 at the current densities of 100 and 1000 mA g−1, respectively. In addition, the SnO2/Co3O4/rGO nanocomposites also exhibit 641 mAh g−1 at a high current density of 1000 mA g−1 after 900 cycles, indicating an ultra-long cycling stability under high current density. Through ex-situ TEM analysis, the excellent electrochemical performance was attributed to the catalytic effect of Co nanoparticles to promote the conversion of Sn to SnO2 and the decomposition of Li2O during the delithiation process. Based on the results, herein we propose a new method in employing the catalyst to increase the capacity of alloying-dealloying type anode material to beyond its theoretical value and enhance the electrochemical performance. PMID:25776280

  7. Spray-Drying-Induced Assembly of Skeleton-Structured SnO2/Graphene Composite Spheres as Superior Anode Materials for High-Performance Lithium-Ion Batteries.

    Science.gov (United States)

    Liu, Dongdong; Kong, Zhen; Liu, Xuehua; Fu, Aiping; Wang, Yiqian; Guo, Yu-Guo; Guo, Peizhi; Li, Hongliang; Zhao, Xiu Song

    2018-01-24

    Three-dimensional skeleton-structured assemblies of graphene sheets decorated with SnO 2 nanocrystals are fabricated via a facile and large-scalable spray-drying-induced assembly process with commercial graphene oxide and SnO 2 sol as precursors. The influences of different parameters on the morphology, composition, structure, and electrochemical performances of the skeleton-structured SnO 2 /graphene composite spheres are studied by XRD, TGA, SEM, TEM, Raman spectroscopy, and N 2 adsorption-desorption techniques. Electrochemical properties of the composite spheres as the anode electrode for lithium-ion batteries are evaluated. After 120 cycles under a current density of 100 mA g -1 , the skeleton-structured SnO 2 /graphene spheres still display a specific discharge capacity of 1140 mAh g -1 . It is roughly 9.5 times larger than that of bare SnO 2 clusters. It could still retain a stable specific capacity of 775 mAh g -1 after 50 cycles under a high current density of 2000 mA g -1 , exhibiting extraordinary rate ability. The superconductivity of the graphene skeleton provides the pathway for electron transportation. The large pore volume deduced from the skeleton structure of the SnO 2 /graphene composite spheres increases the penetration of electrolyte and the diffusion of lithium ions and also significantly enhances the structural integrity by acting as a mechanical buffer.

  8. Tin Dioxide as an Effective Antioxidant for Proton Exchange Membrane Fuel Cells

    DEFF Research Database (Denmark)

    Andersen, Shuang Ma; Nørgaard, Casper Frydendal; Larsen, Mikkel Juul

    2015-01-01

    Tin dioxide (SnO2) containing electrodes showed significantly lower radical induced polymer degradation under single cell open circuit voltage (OCV) treatment than SnO2 free electrodes. A backbone related segment was detected under 100%RH, and an oxygen containing side chain segment was detected ...

  9. Cinética de sinterização para sistemas à base de SnO2 por taxa de aquecimento constante Sintering kinetics for SnO2-based systems by constant heating rate

    Directory of Open Access Journals (Sweden)

    S. M. Tebcheran

    2003-04-01

    Full Text Available Cerâmicas densas de óxido de estanho são muito promissoras para aplicações tecnológicas como varistores e cadinhos de fusão de vidros corrosivos. Vários aditivos em pequenas concentrações podem ser usados como promotores de densificação desta cerâmica. No presente trabalho foram estudadas as cinéticas de sinterização do óxido de estanho, considerando o efeito de atmosfera de sinterização e da concentração de MnO2. Sistemas de SnO2-MnO2 foram preparados pelo método dos precursores poliméricos e os pós obtidos foram caracterizados por medidas de área de superfície específica (BET e por difração de raios X. Pós de SnO2 com concentrações variadas de MnO2 foram compactados de forma cilíndrica e sinterizados em dilatômetro com taxa de aquecimento constante e atmosferas controladas. Amostras sinterizadas foram caracterizadas por microscopia eletrônica de varredura. A influência da atmosfera (argônio, ar ou CO2 como também das concentrações de MnO2 na cinética de sinterização foram determinadas. Os dados cinéticos da retração linear foram analisados pelos modelos cinéticos para a fase inicial de sinterização (Woolfrey e Bannister como também para a sinterização global (Su e Johnson permitindo determinar a energia de ativação aparente. De acordo com a determinação da curva mestre de sinterização, a energia de ativação aparente de todo o processo de sinterização foi determinada bem como sua dependência com a atmosfera e concentrações de manganês. Baseado nestes valores e no expoente n, pode-se determinar, pela equação clássica de crescimento de grão, que o mecanismo de sinterização mais provável é de difusão por contorno de grão com redistribuição superficial controlando a cinética de sinterização.Dense tin oxide based ceramics are very promising for technological applications such as varistors and crucibles for melting very corrosive glasses. Several additives have been used

  10. Formation of high-conductivity regions in SnO2-AOx (A - Ti4+, Zr4+, Sb3+, Sb5+) films exposed to ultraviolet radiation of H2

    International Nuclear Information System (INIS)

    Postovalova, G.G.; Roginskaya, Yu.E.; Zav'yalov, S.A.; Galyamov, B.Sh.; Klimasenko, N.L.

    2000-01-01

    Composition, structure and electron properties of SnO 2 films doped by Ti, Zr and Sb oxides were studied. The doped SnO 2 films were determined to contain nano-regions of SnO 2 base crystalline solid solutions and amorphous SnO 2 containing Sn 2+ or Sb 3+ ions and residing at the surface of crystallites or between them. These composition and structure peculiarities affect essentially both electron structure and electrical properties of films. Localized 5s-states of the conductivity range diffused boundary of amorphous SnO 2 partially filled with 5s-electrons of Sn 2+ or Sb 3+ ions serving as traps capture free electrons in the crystalline ranges and motivate high resistance of films [ru

  11. Improvement of physical properties of SnO2 By Gamma Irradiation

    International Nuclear Information System (INIS)

    Elttayef, A. K.

    2012-12-01

    In this work, the structural and optical of properties of (Sno 2 ) thin films prepared by chemical spray pyrolysis technique have been studied before and after irradiation by gamma ray. The films were prepared from mixture of Tin chloride hydrate SnCl 2 .2H 2 O with molar concentration of (0.1 M)at substrate temperature (400)o C and thickness (175,300 nm). X-ray diffraction analysis indicated that all the prepared films have polycrystalline structure. The optical properties of the films were determined by studying the visible and near IR spectrum, which include transmittance, absorbance, reflectance, absorption coefficient and energy gap before and after irradiation by gamma ray. It was found that the irradiance caused increasing the value of transmittance and optical energy gap. (Author)

  12. IMPEDANCE SPECTROSCOPY OF POLYCRYSTALLINE TIN DIOXIDE FILMS

    Directory of Open Access Journals (Sweden)

    D. V. Adamchuck

    2016-01-01

    Full Text Available The aim of this work is the analysis of the influence of annealing in an inert atmosphere on the electrical properties and structure of non-stoichiometric tin dioxide films by means of impedance spectroscopy method. Non-stoichiometric tin dioxide films were fabricated by two-step oxidation of metallic tin deposited on the polycrystalline Al2O3 substrates by DC magnetron sputtering. In order to modify the structure and stoichiometric composition, the films were subjected to the high temperature annealing in argon atmosphere in temperature range 300–800 °С. AC-conductivity measurements of the films in the frequency range 20 Hz – 2 MHz were carried out. Variation in the frequency dependencies of the real and imaginary parts of the impedance of tin dioxide films was found to occur as a result of high-temperature annealing. Equivalent circuits for describing the properties of films with various structure and stoichiometric composition were proposed. Possibility of conductivity variation of the polycrystalline tin dioxide films as a result of аnnealing in an inert atmosphere was demonstrated by utilizing impedance spectroscopy. Annealing induces the recrystallization of the films, changing in their stoichiometry as well as increase of the sizes of SnO2 crystallites. Variation of electrical conductivity and structure of tin dioxide films as a result of annealing in inert atmosphere was confirmed by X-ray diffraction analysis. Analysis of the impedance diagrams of tin dioxide films was found to be a powerful tool to study their electrical properties. 

  13. Dually fixed SnO2 nanoparticles on graphene nanosheets by polyaniline coating for superior lithium storage.

    Science.gov (United States)

    Dong, Yanfeng; Zhao, Zongbin; Wang, Zhiyu; Liu, Yang; Wang, Xuzhen; Qiu, Jieshan

    2015-02-04

    Dually fixed SnO2 nanoparticles (DF-SnO2 NPs) on graphene nanosheets by a polyaniline (Pani) coating was successfully fabricated via two facile wet chemistry processes, including anchoring SnO2 NPs onto graphene nanosheets via reducing graphene oxide by Sn(2+) ion, followed by in situ surface sealing with the Pani coating. Such a configuration is very appealing anode materials in LIBs due to several structural merits: (1) it prevents the aggregation of SnO2 NPs, (2) accommodates the structural expanding of SnO2 NPs during lithiation, (3) ensures the stable as-formed solid electrolyte interface films, and (4) effectively enhances the electronic conductivity of the overall electrode. Therefore, the final DF-SnO2 anode exhibits stable cycle performance, such as a high capacity retention of over 90% for 400 cycles at a current density of 200 mA g(-1) and a long cycle life up to 700 times at a higher current density of 1000 mA g(-1).

  14. Ultrahigh broadband photoresponse of SnO2 nanoparticle thin film/SiO2/p-Si heterojunction.

    Science.gov (United States)

    Ling, Cuicui; Guo, Tianchao; Lu, Wenbo; Xiong, Ya; Zhu, Lei; Xue, Qingzhong

    2017-06-29

    The SnO 2 /Si heterojunction possesses a large band offset and it is easy to control the transportation of carriers in the SnO 2 /Si heterojunction to realize high-response broadband detection. Therefore, we investigated the potential of the SnO 2 nanoparticle thin film/SiO 2 /p-Si heterojunction for photodetectors. It is demonstrated that this heterojunction shows a stable, repeatable and broadband photoresponse from 365 nm to 980 nm. Meanwhile, the responsivity of the device approaches a high value in the range of 0.285-0.355 A W -1 with the outstanding detectivity of ∼2.66 × 10 12 cm H 1/2 W -1 and excellent sensitivity of ∼1.8 × 10 6 cm 2 W -1 , and its response and recovery times are extremely short (oxide or oxide/Si based photodetectors. In fact, the photosensitivity and detectivity of this heterojunction are an order of magnitude higher than that of 2D material based heterojunctions such as (Bi 2 Te 3 )/Si and MoS 2 /graphene (photosensitivity of 7.5 × 10 5 cm 2 W -1 and detectivity of ∼2.5 × 10 11 cm H 1/2 W -1 ). The excellent device performance is attributed to the large Fermi energy difference between the SnO 2 nanoparticle thin film and Si, SnO 2 nanostructure, oxygen vacancy defects and thin SiO 2 layer. Consequently, practical highly-responsive broadband PDs may be actualized in the future.

  15. Understanding the gas sensing properties of polypyrrole coated tin oxide nanofiber mats

    Science.gov (United States)

    Bagchi, Sudeshna; Ghanshyam, C.

    2017-03-01

    Tin oxide-polypyrrole composites have been widely studied for their enhanced sensing performance towards ammonia vapours, but further investigations are required for an understanding of the interaction mechanisms with different target analytes. In this work, polypyrrole coated tin oxide fibers have been synthesized using a two-step approach of electrospinning and vapour phase polymerization for the sensing of ammonia, ethanol, methanol, 2-propanol and acetone vapours. The resistance variation in the presence of these vapours of different nature and concentration is investigated for the determination of sensor response. A decrease in resistance occurred on interaction of tin oxide-polypyrrole with ammonia, as opposed to previous reported works. Partial reduction of polypyrrole due to interfacial interaction with tin oxide has been proposed to explain this behavior. High sensitivity of 7.45 is achieved for 1 ppm ammonia concentration. Furthermore, the sensor exhibited high sensitivity and a faster response towards ethanol vapours although methanol has the highest electron donating capability. The catalytic mechanism has been discussed to explain this interesting behavior. The results reveal that interaction between tin oxide and polypyrrole is crucial to control the predominant sensing mechanism.

  16. Thermally evaporated mechanically hard tin oxide thin films for opto-electronic apllications

    International Nuclear Information System (INIS)

    Tripathy, Sumanta K.; Rajeswari, V. P.

    2014-01-01

    Tungsten doped tin oxide (WTO) and Molybdenum doped tin oxide (MoTO) thin film were deposited on corn glass by thermal evaporation method. The films were annealed at 350°C for one hour. Structural analysis using Xray diffraction data shows both the films are polycrystalline in nature with monoclinic structure of tin oxide, Sn 3 O 4 , corresponding to JCPDS card number 01-078-6064. SEM photograph showed that both the films have spherical grains with size in the range of 20–30 nm. Compositional analysis was carried out using EDS which reveals the presence of Sn, O and the dopant Mo/W only thereby indicating the absence of any secondary phase in the films. The films are found to contain nearly 6 wt% of Mo, 8 wt% of W as dopants respectively. The transmission pattern for both the films in the spectral range 200 – 2000 nm shows that W doping gives a transparency of nearly 80% from 380 nm onwards while Mo doping has less transparency of 39% at 380nm. Film hardness measurement using Triboscope shows a film hardness of about 9–10 GPa for both the films. It indicates that W or M doping in tin oxide provides the films the added advantage of withstanding the mechanical wear and tear due to environmental fluctuations By optimizing the optical and electrical properties, W/Mo doped tin oxide films may be explored as window layers in opto-electronic applications such as solar cells

  17. Steam regenerative removal of hydrogen sulfide from hot syngas by a novel tin oxide and yttrium oxide sorbent

    International Nuclear Information System (INIS)

    Yang, Yi; Shi, Yixiang; Cai, Ningsheng

    2017-01-01

    A novel H 2 S sorbent based on SnO 2 and Y 2 O 3 is developed by a co-precipitation method for steam regenerative removal of H 2 S from hot syngas at moderate temperatures (400–500 °C). SnO 2 -Y 2 O 3 sorbent is stable in a reducing atmosphere (i.e. 500 °C, 50% H 2 ) and achieves a 99.9% H 2 S removal during successive desulfurization and regeneration cycles. The addition of yttrium to SnO 2 decreases the reduction property of SnO 2 and no metallic Sn exists in the reducing atmosphere due to the formation of a pyrochlore-type compound, Y 2 Sn 2 O 7 . The SnO 2 -Y 2 O 3 sorbent has a desulfurization performance deterioration with the increasing calcination temperature. The newly developed SnO 2 -Y 2 O 3 sorbent can be regenerated by steam at 500 °C. In the eight successive desulfurization and regeneration cycles, SnO 2 -Y 2 O 3 sorbent has a cyclic breakthrough sulfur capacity of 9 mg/g without significant sulfur capacity loss. - Highlights: • Reversible warm gas H 2 S clean up. • Suppressing SnO 2 reduction by formation of Sn 2 Y 2 O 7 . • Sn2Y-700 steam regeneration and cycling characterization.

  18. Change in the electrical conductivity of SnO2 crystal from n-type to p-type conductivity

    International Nuclear Information System (INIS)

    Villamagua, Luis; Stashans, Arvids; Lee, Po-Ming; Liu, Yen-Shuo; Liu, Cheng-Yi; Carini, Manuela

    2015-01-01

    Highlights: • Switch from n-type to p-type conductivity in SnO 2 has been studied. • Computational DFT + U method where used. • X-ray diffraction and X-ray photoelectron spectroscopy where used. • Al- and N-codoped SnO 2 compound shows stable p-type conductivity. • Low resistivity (3.657 × 10 −1 Ω cm) has been obtained. • High carrier concentration (4.858 × 10 19 cm −3 ) has been obtained. - Abstract: The long-sought fully transparent technology will not come true if the n region of the p–n junction does not get as well developed as its p counterpart. Both experimental and theoretical efforts have to be used to study and discover phenomena occurring at the microscopic level in SnO 2 systems. In the present paper, using the DFT + U approach as a main tool and the Vienna ab initio Simulation Package (VASP) we reproduce both intrinsic n-type as well as p-type conductivity in concordance to results observed in real samples of SnO 2 material. Initially, an oxygen vacancy (1.56 mol% concentration) combined with a tin-interstitial (1.56 mol% concentration) scheme was used to achieve the n-type electrical conductivity. Later, to attain the p-type conductivity, crystal already possessing n-type conductivity, was codoped with nitrogen (1.56 mol% concentration) and aluminium (12.48 mol% concentration) impurities. Detailed explanation of structural changes endured by the geometry of the crystal as well as the changes in its electrical properties has been obtained. Our experimental data to a very good extent matches with the results found in the DFT + U modelling

  19. Carbon-Coated SnO2 Nanorod Array for Lithium-Ion Battery Anode Material

    Directory of Open Access Journals (Sweden)

    Ji Xiaoxu

    2010-01-01

    Full Text Available Abstract Carbon-coated SnO2 nanorod array directly grown on the substrate has been prepared by a two-step hydrothermal method for anode material of lithium-ion batteries (LIBs. The structural, morphological and electrochemical properties were investigated by means of X-ray diffraction (XRD, scanning electron microscopy (SEM, transmission electron microscopy (TEM and electrochemical measurement. When used as anodes for LIBs with high current density, as-obtained array reveals excellent cycling stability and rate capability. This straightforward approach can be extended to the synthesis of other carbon-coated metal oxides for application of LIBs.

  20. Reactivation of a Tin-Oxide-Containing Catalyst

    Science.gov (United States)

    Hess, Robert; Sidney, Barry; Schryer, David; Miller, Irvin; Miller, George; Upchurch, Bill; Davis, Patricia; Brown, Kenneth

    2010-01-01

    The electrons in electric-discharge CO2 lasers cause dissociation of some CO2 into O2 and CO, and attach themselves to electronegative molecules such as O2, forming negative O2 ions, as well as larger negative ion clusters by collisions with CO or other molecules. The decrease in CO2 concentration due to dissociation into CO and O2 will reduce the average repetitively pulsed or continuous wave laser power, even if no disruptive negative ion instabilities occur. Accordingly, it is the primary object of this invention to extend the lifetime of a catalyst used to combine the CO and O2 products formed in a laser discharge. A promising low-temperature catalyst for combining CO and O2 is platinum on tin oxide (Pt/SnO2). First, the catalyst is pretreated by a standard procedure. The pretreatment is considered complete when no measurable quantity of CO2 is given off by the catalyst. After this standard pretreatment, the catalyst is ready for its low-temperature use in the sealed, high-energy, pulsed CO2 laser. However, after about 3,000 minutes of operation, the activity of the catalyst begins to slowly diminish. When the catalyst experiences diminished activity during exposure to the circulating gas stream inside or external to the laser, the heated zone surrounding the catalyst is raised to a temperature between 100 and 400 C. A temperature of 225 C was experimentally found to provide an adequate temperature for reactivation. During this period, the catalyst is still exposed to the circulating gas inside or external to the laser. This constant heating and exposing the catalyst to the laser gas mixture is maintained for an hour. After heating and exposing for an appropriate amount of time, the heated zone around the catalyst is allowed to return to the nominal operating temperature of the CO2 laser. This temperature normally resides in the range of 23 to 100 C. Catalyst activity can be measured as the percentage conversion of CO to CO2. In the specific embodiment

  1. Current-voltage characteristics of SnO2-Co3O4-Cr2O3-Sb2O5 ceramics

    International Nuclear Information System (INIS)

    Aguilar-Martinez, J A; Glot, A B; Gaponov, A V; Hernandez, M B; Guerrero-Paz, J

    2009-01-01

    The effect of mechanical treatment in a planetary mill on the microstructure and electrical properties of tin dioxide based varistor ceramics in the system SnO 2 -Co 3 O 4 -Cr 2 O 3 -Sb 2 O 5 sintered in the range 1150-1450 0 C was studied. The mechanical treatment leads to an increase in shrinkage, decrease in porosity, decrease in sample diameter, change in colour of the sintered samples from grey to black and enhancement of nonlinearity. For the sample sintered at 1350 0 C the mechanical treatment enhances the nonlinearity coefficient from 11 to 31 and decreases the electric field E 1 (at 10 -3 A cm -2 ) from 3500 to 2800 V cm -1 . The observed changes in physical properties are explained in terms of an additional size reduction of oxide particles and a better mixing of oxide powder followed by the formation of potential barriers at the grain boundaries throughout the whole sample. In spite of the low porosity, the low-field electrical conductivity of mechanically treated ceramics is significantly increased with the growth of relative humidity. A higher humidity sensitivity is found for mechanically treated ceramics with higher barrier height and higher nonlinearity coefficient.

  2. First-principles analysis of structural and opto-electronic properties of indium tin oxide

    Science.gov (United States)

    Tripathi, Madhvendra Nath; Shida, Kazuhito; Sahara, Ryoji; Mizuseki, Hiroshi; Kawazoe, Yoshiyuki

    2012-05-01

    Density functional theory (DFT) and DFT + U (DFT with on-site Coulomb repulsion corrections) calculations have been carried out to study the structural and opto-electronic properties of indium tin oxide (ITO) for both the oxidized and reduced environment conditions. Some of the results obtained by DFT calculations differ from the experimental observations, such as uncertain indication for the site preference of tin atom to replace indium atom at b-site or d-site, underestimation of local inward relaxation in the first oxygen polyhedra around tin atom, and also the improper estimation of electronic density of states and hence resulting in an inappropriate optical spectra of ITO. These discrepancies of theoretical outcomes with experimental observations in ITO arise mainly due to the underestimation of the cationic 4d levels within standard DFT calculations. Henceforth, the inclusion of on-site corrections within DFT + U framework significantly modifies the theoretical results in better agreement to the experimental observations. Within this framework, our calculations show that the indium b-site is preferential site over d-site for tin atom substitution in indium oxide under both the oxidized and reduced conditions. Moreover, the calculated average inward relaxation value of 0.16 Å around tin atom is in good agreement with the experimental value of 0.18 Å. Furthermore, DFT + U significantly modify the electronic structure and consequently induce modifications in the calculated optical spectra of ITO.

  3. Effect of cationic/anionic organic surfactants on evaporation induced self assembled tin oxide nanostructured films

    International Nuclear Information System (INIS)

    Khun Khun, Kamalpreet; Mahajan, Aman; Bedi, R.K.

    2011-01-01

    Tin oxide nanostructures with well defined morphologies have been obtained through an evaporation induced self assembly process. The technique has been employed using an ultrasonic nebulizer for production of aersol and its subsequent deposition onto a heated glass substrate. The precursor used for aersol production was modified by introducing cationic and anionic surfactants namely cetyl trimethyl ammonium bromide and sodium dodecyl sulphate respectively. The effect of surfactants on the structural, electrical and optical properties of self assembled tin oxide nanostructures were investigated by using X-ray diffraction, field emission scanning electroscope microscopy, two probe technique and photoluminiscence studies. The results reveal that high concentration of surfactants in the precursor solution leads to reduction in crystallite size with significant changes in the morphology of tin oxide nanostructures. Photoluminiscence studies of the nanostructures show emissions in the visible region which exhibit marked changes in the intensities upon variation of surfactants in the precursor solutions.

  4. Effect of cationic/anionic organic surfactants on evaporation induced self assembled tin oxide nanostructured films

    Energy Technology Data Exchange (ETDEWEB)

    Khun Khun, Kamalpreet [Material Science Laboratory, Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India); Mahajan, Aman, E-mail: dramanmahajan@yahoo.co.in [Material Science Laboratory, Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India); Bedi, R.K. [Material Science Laboratory, Department of Physics, Guru Nanak Dev University, Amritsar 143005 (India)

    2011-01-15

    Tin oxide nanostructures with well defined morphologies have been obtained through an evaporation induced self assembly process. The technique has been employed using an ultrasonic nebulizer for production of aersol and its subsequent deposition onto a heated glass substrate. The precursor used for aersol production was modified by introducing cationic and anionic surfactants namely cetyl trimethyl ammonium bromide and sodium dodecyl sulphate respectively. The effect of surfactants on the structural, electrical and optical properties of self assembled tin oxide nanostructures were investigated by using X-ray diffraction, field emission scanning electroscope microscopy, two probe technique and photoluminiscence studies. The results reveal that high concentration of surfactants in the precursor solution leads to reduction in crystallite size with significant changes in the morphology of tin oxide nanostructures. Photoluminiscence studies of the nanostructures show emissions in the visible region which exhibit marked changes in the intensities upon variation of surfactants in the precursor solutions.

  5. Tin Oxide/Graphene Aerogel Nanocomposites Building Superior Rate Capability for Lithium Ion Batteries

    International Nuclear Information System (INIS)

    Fan, Linlin; Li, Xifei; Cui, Yanhua; Xu, Hui; Zhang, Xianfa; Xiong, Dongbin; Yan, Bo; Wang, Yufen; Li, Dejun

    2015-01-01

    Highlights: • The SnO 2 /GA nanocomposites were successfully synthesized via a hydrothermal method. • The performance of nanocomposite anodes highly depended on the hydrothermal time. • The 3-4 nm-sized SnO 2 /GAs showed enhanced cycling performance and rate performance. - Abstract: SnO 2 has attracted intense interest for use as an anode material for lithium ion batteries because of various advantages of the high theoretical capacity and low-cost. Unfortunately, SnO 2 anode material suffers from the huge volume change and poor electrical conductivity. In order to address these problems, in this work, SnO 2 /graphene aerogel composites have been successfully synthesized by a facile hydrothermal approach. 3-4 nm-sized SnO 2 nanoparticles are uniformly dispersed over graphene aerogels. Our results indicate that the hydrothermal reaction time highly affects the electrode performance of the anodes. The nanocomposite electrode with reaction time of 3 h shows increased electrochemical performance with high energy capacity, long cycle life, and superior rate capability. After 100 cycles, it can deliver a high discharge capacity of 662 mAh g −1 at 100 mA g −1 . At 500 mA g −1 , it can still yield a discharge capacity of 619.7 mAh g −1 after 723 cycles. The performance improvement can attribute to the graphene aerogel, which can suppress the aggregation of SnO 2 nanoparticles, enhance the conductivity of SnO 2 , and increase their structural stability during cycling. This study strongly demonstrates that the SnO 2 /graphene aerogel composite is a promising anode material building high performance lithium ion batteries

  6. Mesoporous Tin-Based Oxide Nanospheres/Reduced Graphene Composites as Advanced Anodes for Lithium-Ion Half/Full Cells and Sodium-Ion Batteries.

    Science.gov (United States)

    He, Yanyan; Li, Aihua; Dong, Caifu; Li, Chuanchuan; Xu, Liqiang

    2017-10-04

    The large volume variations of tin-based oxides hinder their extensive application in the field of lithium-ion batteries (LIBs). In this study, structure design, hybrid fabrication, and carbon-coating approaches have been simultaneously adopted to address these shortcomings. To this end, uniform mesoporous NiO/SnO 2 @rGO, Ni-Sn oxide@rGO, and SnO 2 @rGO nanosphere composites have been selectively fabricated. Among them, the obtained NiO/SnO 2 @rGO composite exhibited a high capacity of 800 mAh g -1 at 1000 mA g -1 after 400 cycles. The electrochemical mechanism of NiO/SnO 2 as an anode for LIBs has been preliminarily investigated by ex situ XRD pattern analysis. Furthermore, an NiO/SnO 2 @rGO-LiCoO 2 lithium-ion full cell showed a high capacity of 467.8 mAh g -1 at 500 mA g -1 after 100 cycles. Notably, the NiO/SnO 2 @rGO composite also showed good performance when investigated as an anode for sodium-ion batteries (SIBs). It is believed that the unique mesoporous nanospherical framework, synergistic effects between the various components, and uniform rGO wrapping of NiO/SnO 2 shorten the Li + ion diffusion pathways, maintain sufficient contact between the active material and the electrolyte, mitigate volume changes, and finally improve the electrical conductivity of the electrode. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Nanocrystalline SnO2 by liquid pyrolysis

    Directory of Open Access Journals (Sweden)

    Morante, J. R.

    2000-08-01

    Full Text Available Liquid pyrolysis is presented as a new production method of SnO2 nanocrystalline powders suitable for gas sensor devices. The method is based on a pyrolytic reaction of high tensioned stressed drops of an organic solution of SnCl4•5(H2O. The main advantages of the method are its capability to produce SnO2 nanopowders with high stability, its accurate control over the grain size and other structural characteristics, its high level of repeatability and its low industrialization implementation cost. The characterization of samples of SnO2 nanoparticles obtained by liquid pyrolysis in the range between 200ºC and 900ºC processing temperature is carried out by X-ray diffraction, transmission electron microscopy, Raman and X-ray photoelectron spectroscopy. Results are analyzed and discussed so as to validate the advantages of the liquid pyrolysis method.La pirólisis líquida se presenta como un nuevo método para producir SnO2 nanocristalino en polvo ideal para sensores de gas. El método se basa en una reacción pirolítica de gotas altamente tensionadas procedentes de una solución orgánica de SnCl4•5(H2O. Las principales ventajas del método son la capacidad para producir nanopartículas de SnO2 con una gran estabilidad, el preciso control sobre el tamaño de grano y sobre otras características estructurales, el alto nivel de repetibilidad y el bajo coste en su implementación industrial.La caracterización de las muestras de las nanopartículas de SnO2 obtenidas por pirólisis líquida en un rango de temperatura de procesado que va de 200ºC a 900ºC se ha realizado mediante difracción de rayos X, microscopía electrónica de transmisión, espectroscopía Raman y espectroscopía fotoelectrónica de rayos X. Los resultados se han analizado y discutido. Éstos validan las ventajas del método de la pirólisis líquida.

  8. SnO2Nanowire Arrays and Electrical Properties Synthesized by Fast Heating a Mixture of SnO2and CNTs Waste Soot

    Directory of Open Access Journals (Sweden)

    Zhou Zhi-Hua

    2009-01-01

    Full Text Available Abstract SnO2nanowire arrays were synthesized by fast heating a mixture of SnO2and the carbon nanotubes waste soot by high-frequency induction heating. The resultant SnO2nanowires possess diameters from 50 to 100 nm and lengths up to tens of mircrometers. The field-effect transistors based on single SnO2nanowire exhibit that as-synthesized nanowires have better transistor performance in terms of transconductance and on/off ratio. This work demonstrates a simple technique to the growth of nanomaterials for application in future nanoelectronic devices.

  9. Post-deposition annealing effects in RF reactive magnetron sputtered indium tin oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Martinez, M A; Herrero, J; Gutierrez, M T [Inst. de Energias Renovables (CIEMAT), Madrid (Spain)

    1992-05-01

    Indium tin oxide films have been grown by RF reactive magnetron sputtering. The influence of the deposition parameters on the properties of the films has been investigated and optimized, obtaining a value for the figure of merit of 6700 ({Omega} cm){sup -1}. As-grown indium tin oxide films were annealed in vacuum and O{sub 2} atmosphere. After these heat treatments the electro-optical properties were improved, with values for the resistivity of 1.9x10{sup -4} {Omega} cm and the figure of merit of 26700 ({Omega} cm){sup -1}. (orig.).

  10. Spray deposited gallium doped tin oxide thinfilm for acetone sensor application

    Science.gov (United States)

    Preethi, M. S.; Bharath, S. P.; Bangera, Kasturi V.

    2018-04-01

    Undoped and gallium doped (1 at.%, 2 at.% and 3 at.%) tin oxide thin films were prepared using spray pyrolysis technique by optimising the deposition conditions such as precursor concentration, substrate temperature and spraying rate. X-ray diffraction analysis revealed formation of tetragonally structured polycrystalline films. The SEM micrographs of Ga doped films showed microstructures. The electrical resistivity of the doped films was found to be more than that of the undoped films. The Ga-doped tin oxide thin films were characterised for gas sensors. 1 at.% Ga doped thin films were found to be better acetone gas sensor, showed 68% sensitivity at 350°C temperature.

  11. Effect of fabrication conditions on the properties of indium tin oxide powders

    International Nuclear Information System (INIS)

    Xie Wei

    2008-01-01

    This paper reports that indium tin oxide (ITO) crystalline powders are prepared by coprecipitation method. Fabrication conditions mainly as sintering temperature and Sn doping content are correlated with the phase, microstructure, infrared emissivity in and powder resistivity of indium tin oxides by means of x-ray diffraction, Fourier transform infrared, and transmission electron microscope. The optimum sintering temperature of 1350°C and Sn doping content 6∼8wt% are determined. The application of ITO in the military camouflage field is proposed. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  12. One-step in situ synthesis of SnO2/graphene nanocomposites and its application as an anode material for Li-ion batteries.

    Science.gov (United States)

    Liang, Junfei; Wei, Wei; Zhong, Da; Yang, Qinglin; Li, Lidong; Guo, Lin

    2012-01-01

    A facile one-step solution-based process to in situ synthesize SnO(2)/graphene (SG) nanocomposites was developed, by using the mixture of dimethyl sulfoxide (DMSO) and H(2)O as both solvent and reactant. The reduction of graphene oxide (GO) and the in situ formation of SnO(2) nanoparticles were realized in one step. The electrochemical experiments showed the composites provided a better Li-storage performance. The method presented in this paper may provide an effective, economic, and green strategy for the preparation of metal-oxide/graphene nanocomposites. © 2011 American Chemical Society

  13. Preparation of SnO2 Nanoparticles by Two Different Wet Chemistry Methods

    International Nuclear Information System (INIS)

    Ridha, N.J.; Akrajas Ali Umar; Muhammad Yahya; Muhammad Mat Salleh; Mohamad Hafizuddin Jumali

    2011-01-01

    The objective of this project is to prepare SnO 2 nanoparticles by two different wet chemistry methods namely sol gel and direct growth methods. The XRD results indicated that both samples are single phase SnO 2 . The FE-SEM micrographs displayed that SnO 2 nanoparticles prepared in first method exhibited a round shape with particle size around 15 nm while the second method produced SnO 2 nano rod with length and width of 570 nm and 55 nm respectively. Energy gap values for SnO 2 nanospheres and nano rods were 4.38 and 4.34 eV respectively. (author)

  14. Mn-implanted, polycrystalline indium tin oxide and indium oxide films

    International Nuclear Information System (INIS)

    Scarlat, Camelia; Vinnichenko, Mykola; Xu Qingyu; Buerger, Danilo; Zhou Shengqiang; Kolitsch, Andreas; Grenzer, Joerg; Helm, Manfred; Schmidt, Heidemarie

    2009-01-01

    Polycrystalline conducting, ca. 250 nm thick indium tin oxide (ITO) and indium oxide (IO) films grown on SiO 2 /Si substrates using reactive magnetron sputtering, have been implanted with 1 and 5 at.% of Mn, followed by annealing in nitrogen or in vacuum. The effect of the post-growth treatment on the structural, electrical, magnetic, and optical properties has been studied. The roughness of implanted films ranges between 3 and 15 nm and XRD measurements revealed a polycrystalline structure. A positive MR has been observed for Mn-implanted and post-annealed ITO and IO films. It has been interpreted by considering s-d exchange. Spectroscopic ellipsometry has been used to prove the existence of midgap electronic states in the Mn-implanted ITO and IO films reducing the transmittance below 80%.

  15. Nitrogen Dioxide-Sensing Properties at Room Temperature of Metal Oxide-Modified Graphene Composite via One-Step Hydrothermal Method

    Science.gov (United States)

    Zhang, Dongzhi; Liu, Jingjing; Xia, Bokai

    2016-08-01

    A metal oxide/graphene composite film-based sensor toward room-temperature detection of ppm-level nitrogen dioxide (NO2) gas has been demonstrated. The sensor prototype was constructed on a PCB substrate with microelectrodes, and a tin oxide-reduced graphene oxide (SnO2-rGO) composite as sensing film was prepared by one-step hydrothermal synthesis of tin tetrachloride pentahydrate solution in the presence of graphene oxide (GO). The SnO2-rGO hybrid composite was examined by scanning electron microscope and x-ray diffraction (XRD). The gas sensing properties of the SnO2-rGO composite were investigated at room temperature by exposing it to a wide concentration ranging from 1 ppm to 2000 ppm toward NO2 gas. The experiment results showed that the sensor exhibited a high response, superior selectivity, good repeatability, rapid response/recovery characteristics and low detection limit of 1 ppm, which exceeded that of a pure rGO sensor. The gas sensing mechanisms of the proposed sensor toward NO2 were possibly attributed to the nano-hybrid structures and n- p heterojunctions created at the interface of the SnO2 nanocrystals and rGO nanosheets.

  16. Physicochemical characterization of point defects in fluorine doped tin oxide films

    Science.gov (United States)

    Akkad, Fikry El; Joseph, Sudeep

    2012-07-01

    The physical and chemical properties of spray deposited FTO films are studied using FESEM, x-ray diffraction (XRD), x-ray photoelectron spectroscopy (XPS), electrical and optical measurements. The results of XRD measurements showed that the films are polycrystalline (grain size 20-50 nm) with Rutile structure and mixed preferred orientation along the (200) and (110) planes. An angular shift of the XRD peaks after F-doping is observed and interpreted as being due to the formation of substitutional fluorine defects (FO) in presence of high concentration of oxygen vacancies (VO) that are electrically neutral. The electrical neutrality of oxygen vacancies is supported by the observation that the electron concentration n is two orders of magnitude lower than the VO concentration calculated from chemical analyses using XPS measurements. It is shown that an agreement between XPS, XRD, and Hall effect results is possible provided that the degree of deviation from stoichiometry is calculated with the assumption that the major part of the bulk carbon content is involved in O-C bonds. High temperature thermal annealing is found to cause an increase in the FO concentration and a decrease in both n and VO concentrations with the increase of the annealing temperature. These results could be interpreted in terms of a high temperature chemical exchange reaction between the SnO2 matrix and a precipitated fluoride phase. In this reaction, fluorine is released to the matrix and Sn is trapped by the fluoride phase, thus creating substitutional fluorine FO and tin vacancy VSn defects. The enthalpy of this reaction is determined to be approximately 2.4 eV while the energy of formation of a VSn through the migration of SnSn host atom to the fluoride phase is approximately 0.45 eV.

  17. XPS-nanocharacterization of organic layers electrochemically grafted on the surface of SnO_2 thin films to produce a new hybrid material coating

    International Nuclear Information System (INIS)

    Drevet, R.; Dragoé, D.; Barthés-Labrousse, M.G.; Chaussé, A.; Andrieux, M.

    2016-01-01

    Graphical abstract: An innovative hybrid material layer is synthesized by combining two processes. SnO_2 thin films are deposited by MOCVD on Si substrates and an organic layer made of carboxyphenyl moieties is electrochemically grafted by the reduction of a diazonium salt. XPS characterizations are carried out to assess the efficiency of the electrochemical grafting. Display Omitted - Highlights: • An innovative hybrid material layer is synthesized by combining two processes. • SnO_2 thin films are deposited by MOCVD on Si substrates. • An organic layer is electrochemically grafted by the reduction of a diazonium salt. • The efficiency of the grafting is accurately assessed by XPS. • Three electrochemical grafting models are proposed. - Abstract: This work presents the synthesis and the characterization of hybrid material thin films obtained by the combination of two processes. The electrochemical grafting of organic layers made of carboxyphenyl moieties is carried out from the reduction of a diazonium salt on tin dioxide (SnO_2) thin films previously deposited on Si substrates by metal organic chemical vapor deposition (MOCVD). Since the MOCVD experimental parameters impact the crystal growth of the SnO_2 layer (i.e. its morphology and its texturation), various electrochemical grafting models can occur, producing different hybrid materials. In order to evidence the efficiency of the electrochemical grafting of the carboxyphenyl moieties, X-ray Photoelectron Spectroscopy (XPS) is used to characterize the first nanometers in depth of the synthesized hybrid material layer. Then three electrochemical grafting models are proposed.

  18. Nanostructured antistatic and antireflective thin films made of indium tin oxide and silica over-coat layer

    Science.gov (United States)

    Cho, Young-Sang; Hong, Jeong-Jin; Yang, Seung-Man; Choi, Chul-Jin

    2010-08-01

    Stable dispersion of colloidal indium tin oxide nanoparticles was prepared by using indium tin oxide nanopowder, organic solvent, and suitable dispersants through attrition process. Various comminution parameters during the attrition step were studied to optimize the process for the stable dispersion of indium tin oxide sol. The transparent and conductive films were fabricated on glass substrate using the indium tin oxide sol by spin coating process. To obtain antireflective function, partially hydrolyzed alkyl silicate was deposited as over-coat layer on the pre-fabricated indium tin oxide film by spin coating technique. This double-layered structure of the nanostructured film was characterized by measuring the surface resistance and reflectance spectrum in the visible wavelength region. The final film structure was enough to satisfy the TCO regulations for EMI shielding purposes.

  19. Preparation of transparent conductive indium tin oxide thin films from nanocrystalline indium tin hydroxide by dip-coating method

    International Nuclear Information System (INIS)

    Koroesi, Laszlo; Papp, Szilvia; Dekany, Imre

    2011-01-01

    Indium tin oxide (ITO) thin films with well-controlled layer thickness were produced by dip-coating method. The ITO was synthesized by a sol-gel technique involving the use of aqueous InCl 3 , SnCl 4 and NH 3 solutions. To obtain stable sols for thin film preparation, as-prepared Sn-doped indium hydroxide was dialyzed, aged, and dispersed in ethanol. Polyvinylpyrrolidone (PVP) was applied to enhance the stability of the resulting ethanolic sols. The transparent, conductive ITO films on glass substrates were characterized by X-ray diffraction, scanning electron microscopy and UV-Vis spectroscopy. The ITO layer thickness increased linearly during the dipping cycles, which permits excellent controllability of the film thickness in the range ∼ 40-1160 nm. After calcination at 550 o C, the initial indium tin hydroxide films were transformed completely to nanocrystalline ITO with cubic and rhombohedral structure. The effects of PVP on the optical, morphological and electrical properties of ITO are discussed.

  20. Investigation of TiN thin film oxidation depending on the substrate temperature at vacuum break

    Energy Technology Data Exchange (ETDEWEB)

    Piallat, Fabien, E-mail: fabien.piallat@gmail.com [STMicroelectronics, 850 rue Jean Monnet, 38920 Crolles (France); CEA, LETI, Campus Minatec, F-38054 Grenoble (France); LTM-CNRS, 17 rue des Martyrs, 38054 Grenoble (France); Gassilloud, Remy [CEA, LETI, Campus Minatec, F-38054 Grenoble (France); Caubet, Pierre [STMicroelectronics, 850 rue Jean Monnet, 38920 Crolles (France); Vallée, Christophe [LTM-CNRS, 17 rue des Martyrs, 38054 Grenoble (France)

    2016-09-15

    Due to the reduction of the thickness of the layers used in the advanced technology nodes, there is a growing importance of the surface phenomena in the definition of the general properties of the materials. One of the least controlled and understood phenomenon is the oxidation of metals after deposition, at the vacuum break. In this study, the influence of the sample temperature at vacuum break on the oxidation level of TiN deposited by metalorganic chemical vapor deposition is investigated. TiN resistivity appears to be lower for samples which underwent vacuum break at high temperature. Using X-ray photoelectron spectrometry analysis, this change is correlated to the higher oxidation of the TiN layer. Moreover, angle resolved XPS analysis reveals that higher is the temperature at the vacuum break, higher is the surface oxidation of the sample. This surface oxidation is in turn limiting the diffusion of oxygen in the volume of the layer. Additionally, evolution of TiN layers resistivity was monitored in time and it shows that resistivity increases until a plateau is reached after about 10 days, with the lowest temperature at vacuum break resulting in the highest increase, i.e., the resistivity of the sample released to atmosphere at high temperature increased by a factor 1.7 whereas the resistivity of the sample cooled down under vacuum temperature increased by a factor 2.7.

  1. Influence of the sputtering system's vacuum level on the properties of indium tin oxide films

    International Nuclear Information System (INIS)

    Zebaze Kana, M.G.; Centurioni, E.; Iencinella, D.; Summonte, C.

    2006-01-01

    The influence of the chamber residual pressure level in the radio frequency magnetron sputtering process on the electrical, optical and structural properties of indium thin oxide (ITO) is investigated. Several ITO films were deposited at various residual pressure levels on Corning glass using In 2 O 3 :SnO 2 target in argon atmosphere and without the addition of oxygen partial pressure. It is found that a very good vacuum is associated to metallic films and results in less transparent ITO films, with some powder formation on the surface. On the contrary highly transparent and conducting films are produced at a higher residual pressure. The best deposition conditions are addressed for ITO films as transparent conducting oxide layers in silicon heterojunction solar cells. Using the optimal vacuum level for ITO fabrication, a maximum short circuit current of 36.6 mA/cm 2 and a fill-factor of 0.78 are obtained for solar cells on textured substrates with a device conversion efficiency of 16.2%

  2. Size-controlled synthesis of SnO2 quantum dots and their gas-sensing performance

    International Nuclear Information System (INIS)

    Du, Jianping; Zhao, Ruihua; Xie, Yajuan; Li, Jinping

    2015-01-01

    Graphical abstract: The gas-sensing property of quantum dots is related to their sizes. SnO 2 quantum dots (TQDs) were synthesized and the sizes were controlled by a simple strategy. The results show that controlling QDs size is efficient to detect low-concentration hazardous volatile compounds selectively. - Highlights: • SnO 2 quantum dots with controllable size were synthesized by hydrothermal route. • The sizes of SnO 2 quantum dots (TQDs) were controlled by a simple strategy. • The responses to volatile chemicals strongly depend on the size of quantum dots. • Small-size TQDs exhibit a good selectivity and response to triethylamine. • Controlling size is efficient to detect low-concentration toxic gases selectively. - Abstract: Tin dioxide quantum dots (TQDs) with controllable size were synthesized by changing the amount of alkaline reagent in the hydrothermal process. The gas-sensing properties were investigated by operating chemoresistor type sensor. The morphology and structure were characterized by X-ray diffraction, scanning/transmission electron microscopy, UV–vis and Raman spectrometry. The as-synthesized SnO 2 shows the characteristics of quantum dots and the narrowest size distribution is about 2–3 nm. The gas-sensing results indicate that the responses are strongly dependent on the size of quantum dots. TQDs with different sizes exhibit different sensitivities and selectivities to volatile toxic chemicals such as aldehyde, acetone, methanol, ethanol and amine. Especially, when the sensors are exposed to 100 ppm triethylamine (TEA), the sensing response value of TQDs with small size is two times higher than that of the large-size TQDs. The maximum response values of TQDs to 1 ppm and 100 ppm TEA are 15 and 153, respectively. The response time is 1 s and the recovery time is 47 s upon exposure to 1 ppm TEA. The results suggest that it is an effective method by regulating the size of SnO 2 quantum dots to detect low-concentration hazardous

  3. Generic Top-Functionalization of Patterned Antifouling Zwitterionic Polymers on Indium Tin Oxide

    NARCIS (Netherlands)

    Li, Y.; Giesbers, M.; Zuilhof, H.

    2012-01-01

    This paper presents a novel surface engineering approach that combines photochemical grafting and surface-initiated atom transfer radical polymerization (SI-ATRP) to attach zwitterionic polymer brushes onto indium tin oxide (ITO) substrates. The photochemically grafted hydroxyl-terminated organic

  4. Transparent Conducting Films of Antimony-Doped Tin Oxide with Uniform Mesostructure Assembled from Preformed Nanocrystals

    Czech Academy of Sciences Publication Activity Database

    Müller, V.; Rasp, M.; Rathouský, Jiří; Schütz, B.; Niederberger, M.; Fattakhova-Rohlfing, D.

    2010-01-01

    Roč. 6, č. 5 (2010), s. 633-637 ISSN 1613-6810 R&D Projects: GA ČR GA104/08/0435 Institutional research plan: CEZ:AV0Z40400503 Keywords : antimony -doped tin oxide * msoporous materials * nanoparticles Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 7.333, year: 2010

  5. Self-catalytic growth of tin oxide nanowires by chemical vapor deposition process

    CSIR Research Space (South Africa)

    Thabethe, BS

    2013-01-01

    Full Text Available The authors report on the synthesis of tin oxide (SnO(sub2)) nanowires by a chemical vapor deposition (CVD) process. Commercially bought SnO nanopowders were vaporized at 1050°C for 30 minutes with argon gas continuously passing through the system...

  6. Physical properties of pyrolytically sprayed tin-doped indium oxide coatings

    NARCIS (Netherlands)

    Haitjema, H.; Elich, J.J.P.

    1991-01-01

    The optical and electrical properties of tin-doped indium oxide coatings obviously depend on a number of production parameters. This dependence has been studied to obtain a more general insight into the relationships between the various coating properties. The coatings have been produced by spray

  7. Study of optical characteristics of tin oxide thin film prepared by sol ...

    Indian Academy of Sciences (India)

    wear-resistant coating on glass containers (Nakagawa et al. 1997), Infrared reflectors for ... Tin oxide is a tetragonal n-type semiconductor having high bandgap energy ... (IV) chloride due to the cost factor and availability. The main purpose of ...

  8. Photocatalytic degradation of phenol by iodine doped tin oxide nanoparticles under UV and sunlight irradiation

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hamdi, Abdullah M.; Sillanpää, Mika [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Dutta, Joydeep, E-mail: dutta@squ.edu.om [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman)

    2015-01-05

    Highlights: • A sol–gel method used to synthesize tin oxide nanoparticles. • Nanoparticles of tin oxide doped with different iodine concentrations. • Degradation studies carried up with UV–vis, TOC, HPLC and GC instruments. • 1% iodine doped tin dioxide showed maximum photodegradation efficiency. - Abstract: Iodine doped tin oxide (SnO{sub 2}:I) nanoparticles were prepared by sol–gel synthesis and their photocatalytic activities with phenol as a test contaminant were studied. In the presence of the catalysts, phenol degradation under direct sunlight was comparable to what was achieved under laboratory conditions. Photocatalytic oxidation reactions were studied by varying the catalyst loading, light intensity, illumination time, pH of the reactant and phenol concentration. Upon UV irradiation in the presence of SnO{sub 2}:I nanoparticles, phenol degrades very rapidly within 30 min, forming carboxylic acid which turns the solution acidic. Phenol degradation rate with 1% iodine doped SnO{sub 2} nanoparticles is at least an order of magnitude higher compared to the degradation achieved through undoped SnO{sub 2} nanoparticles under similar illumination conditions.

  9. Crack density and electrical resistance in indium-tin-oxide/polymer thin films under cyclic loading

    KAUST Repository

    Mora Cordova, Angel; Khan, Kamran; El Sayed, Tamer

    2014-01-01

    Here, we propose a damage model that describes the degradation of the material properties of indium-tin-oxide (ITO) thin films deposited on polymer substrates under cyclic loading. We base this model on our earlier tensile test model and show

  10. Controlling the Sn-C bonds content in SnO2@CNTs composite to form in situ pulverized structure for enhanced electrochemical kinetics.

    Science.gov (United States)

    Cheng, Yayi; Huang, Jianfeng; Qi, Hui; Cao, Liyun; Luo, Xiaomin; Li, Jiayin; Xu, Zhanwei; Yang, Jun

    2017-12-07

    The Sn-C bonding content between the SnO 2 and CNTs interface was controlled by the hydrothermal method and subsequent heat treatment. Electrochemical analysis found that the SnO 2 @CNTs with high Sn-C bonding content exhibited much higher capacity contribution from alloying and conversion reaction compared with the low content of Sn-C bonding even after 200 cycles. The high Sn-C bonding content enabled the SnO 2 nanoparticles to stabilize on the CNTs surface, realizing an in situ pulverization process of SnO 2 . The in situ pulverized structure was beneficial to maintain the close electrochemical contact of the working electrode during the long-term cycling and provide ultrafast transfer paths for lithium ions and electrons, which promoted the alloying and conversion reaction kinetics greatly. Therefore, the SnO 2 @CNTs composite with high Sn-C bonding content displayed highly reversible alloying and conversion reaction. It is believed that the composite could be used as a reference for design chemically bonded metal oxide/carbon composite anode materials in lithium-ion batteries.

  11. The Effect of Eu Doping on Microstructure, Morphology and Methanal-Sensing Performance of Highly Ordered SnO2 Nanorods Array

    Directory of Open Access Journals (Sweden)

    Yanping Zhao

    2017-11-01

    Full Text Available Layered Eu-doped SnO2 ordered nanoarrays constructed by nanorods with 10 nm diameters and several hundred nanometers length were synthesized by a substrate-free hydrothermal route using alcohol and water mixed solvent of sodium stannate and sodium hydroxide at 200 °C. The Eu dopant acted as a crystal growth inhibitor to prevent the SnO2 nanorods growth up, resulting in tenuous SnO2 nanorods ordered arrays. The X-ray diffraction (XRD revealed the tetragonal rutile-type structure with a systematic average size reduction and unit cell volume tumescence, while enhancing the residual strain as the Eu-doped content increases. The surface defects that were caused by the incorporation of Eu ions within the surface oxide matrix were observed by high-resolution transmission electron microscope (HRTEM. The results of the response properties of sensors based on the different levels of Eu-doped SnO2 layered nanoarrays demonstrated that the 0.5 at % Eu-doped SnO2 layered nanorods arrays exhibited an excellent sensing response to methanal at 278 °C. The reasons of the enhanced sensing performance were discussed from the complicated defect surface structure, the large specific surface area, and the excellent catalytic properties of Eu dopant.

  12. Parts per billion-level detection of benzene using SnO2/graphene nanocomposite composed of sub-6 nm SnO2 nanoparticles

    International Nuclear Information System (INIS)

    Meng Fanli; Li Huihua; Kong Lingtao; Liu Jinyun; Jin Zhen; Li Wei; Jia Yong; Liu Jinhuai; Huang Xingjiu

    2012-01-01

    Graphical abstract: SnO 2 /graphene nanocomposite composed of 4–5 nm SnO 2 nanoparticles was synthesized by one-step wet chemical method and the form mechanism of the nanocomposite is clearly interpreted. The detection limit of the nanocomposite was as low as 5 ppb to toxic benzene. Highlights: ► We synthesized SnO 2 /graphene nanocomposite using a simple one-step wet chemical method. ► The nanocomposite composed of 4–5 nm SnO 2 nanoparticles. ► Toxic benzene was detected by such kind of nanocomposite. ► The detection limit to toxic benzene was as low as 5 ppb. - Abstract: In the present work, the SnO 2 /graphene nanocomposite composed of 4–5 nm SnO 2 nanoparticles was synthesized using a simple wet chemical method for ppb-level detection of benzene. The formation mechanism of the nanocomposite was investigated systematically by means of simultaneous thermogravimetry analysis, X-ray diffraction, and X-ray photoelectron spectroscopy cooperated with transmission electron microscopy observations. The SnO 2 /graphene nanocomposite showed a very attractive improved sensitivity to toxic volatile organic compounds, especially to benzene, compared to a traditional SnO 2 . The responses of the nanocomposite to benzene were a little higher than those to ethanol and the detection limit reached 5 ppb to benzene which is, to our best knowledge, far lower than those reported previously.

  13. Hollow SnO2@Co3O4 core-shell spheres encapsulated in three-dimensional graphene foams for high performance supercapacitors and lithium-ion batteries

    Science.gov (United States)

    Zhao, Bo; Huang, Sheng-Yun; Wang, Tao; Zhang, Kai; Yuen, Matthew M. F.; Xu, Jian-Bin; Fu, Xian-Zhu; Sun, Rong; Wong, Ching-Ping

    2015-12-01

    Hollow SnO2@Co3O4 spheres are fabricated using 300 nm spherical SiO2 particles as template. Then three-dimensional graphene foams encapsulated hollow SnO2@Co3O4 spheres are successfully obtained through self-assembly in hydrothermal process from graphene oxide nanosheets and metal oxide hollow spheres. The three-dimensional graphene foams encapsulated architectures could greatly improve the capacity, cycling stability and rate capability of hollow SnO2@Co3O4 spheres electrodes due to the highly conductive networks and flexible buffering matrix. The three-dimensional graphene foams encapsulated hollow SnO2@Co3O4 spheres are promising electrode materials for supercapacitors and lithium-ion batteries.

  14. The influence of interfacial barrier engineering on the resistance switching of In2O3:SnO2/TiO2/In2O3:SnO2 device

    International Nuclear Information System (INIS)

    Liu Zi-Yu; Zhang Pei-Jian; Meng Yang; Li Dong; Meng Qing-Yu; Li Jian-Qi; Zhao Hong-Wu

    2012-01-01

    The I—V characteristics of In 2 O 3 :SnO 2 /TiO 2 /In 2 O 3 :SnO 2 junctions with different interfacial barriers are investigated by comparing experiments. A two-step resistance switching process is found for samples with two interfacial barriers produced by specific thermal treatment on the interfaces. The nonsynchronous occurrence of conducting filament formation through the oxide bulk and the reduction in the interfacial barrier due to the migration of oxygen vacancies under the electric field is supposed to explain the two-step resistive switching process. The unique switching properties of the device, based on interfacial barrier engineering, could be exploited for novel applications in nonvolatile memory devices. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  15. Optimized spherical manganese oxide-ferroferric oxide-tin oxide ternary composites as advanced electrode materials for supercapacitors

    Science.gov (United States)

    Zhu, Jian; Tang, Shaochun; Vongehr, Sascha; Xie, Hao; Meng, Xiangkang

    2015-09-01

    Inexpensive MnO2 is a promising material for supercapacitors (SCs), but its application is limited by poor electrical conductivity and low specific surface area. We design and fabricate hierarchical MnO2-based ternary composite nanostructures showing superior electrochemical performance via doping with electrochemically active Fe3O4 in the interior and electrically conductive SnO2 nanoparticles in the surface layer. Optimization composition results in a MnO2-Fe3O4-SnO2 composite electrode material with 5.9 wt.% Fe3O4 and 5.3 wt.% SnO2, leading to a high specific areal capacitance of 1.12 F cm-2 at a scan rate of 5 mV s-1. This is two to three times the values for MnO2-based binary nanostructures at the same scan rate. The low amount of SnO2 almost doubles the capacitance of porous MnO2-Fe3O4 (before SnO2 addition), which is attributed to an improved conductivity and remaining porosity. In addition, the optimal ternary composite has a good rate capability and an excellent cycling performance with stable capacitance retention of ˜90% after 5000 charge/discharge cycles at 7.5 mA cm-2. All-solid-state SCs are assembled with such electrodes using polyvinyl alcohol/Na2SO4 electrolyte. An integrated device made by connecting two identical SCs in series can power a light-emitting diode indicator for more than 10 min.

  16. Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors

    Directory of Open Access Journals (Sweden)

    M. Cihan Çakır

    2016-09-01

    Full Text Available Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption–dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

  17. Planar Indium Tin Oxide Heater for Improved Thermal Distribution for Metal Oxide Micromachined Gas Sensors.

    Science.gov (United States)

    Çakır, M Cihan; Çalışkan, Deniz; Bütün, Bayram; Özbay, Ekmel

    2016-09-29

    Metal oxide gas sensors with integrated micro-hotplate structures are widely used in the industry and they are still being investigated and developed. Metal oxide gas sensors have the advantage of being sensitive to a wide range of organic and inorganic volatile compounds, although they lack selectivity. To introduce selectivity, the operating temperature of a single sensor is swept, and the measurements are fed to a discriminating algorithm. The efficiency of those data processing methods strongly depends on temperature uniformity across the active area of the sensor. To achieve this, hot plate structures with complex resistor geometries have been designed and additional heat-spreading structures have been introduced. In this work we designed and fabricated a metal oxide gas sensor integrated with a simple square planar indium tin oxide (ITO) heating element, by using conventional micromachining and thin-film deposition techniques. Power consumption-dependent surface temperature measurements were performed. A 420 °C working temperature was achieved at 120 mW power consumption. Temperature distribution uniformity was measured and a 17 °C difference between the hottest and the coldest points of the sensor at an operating temperature of 290 °C was achieved. Transient heat-up and cool-down cycle durations are measured as 40 ms and 20 ms, respectively.

  18. Preparation of porous titanium oxide films onto indium tin oxide for application in organic photovoltaic devices

    Energy Technology Data Exchange (ETDEWEB)

    Macedo, Andreia G. [Laboratorio de Dispositivos Nanoestruturados, Departamento de Fisica, Universidade Federal do Parana, Curitiba, Parana (Brazil); Mattos, Luana L.; Spada, Edna R.; Serpa, Rafael B.; Campos, Cristiani S. [Laboratorio de Sistemas Nanoestruturados, Departamento de Fisica, Universidade Federal de Santa Catarina, Florianopolis, Santa Catarina (Brazil); Grova, Isabel R.; Ackcelrud, Leni [Laboratorio de Polimeros Paulo Scarpa, Departamento de Quimica, Universidade Federal do Parana, Curitiba, Parana (Brazil); Reis, Francoise T.; Sartorelli, Maria L. [Laboratorio de Sistemas Nanoestruturados, Departamento de Fisica, Universidade Federal de Santa Catarina, Florianopolis, Santa Catarina (Brazil); Roman, Lucimara S., E-mail: lsroman@fisica.ufpr.br [Laboratorio de Dispositivos Nanoestruturados, Departamento de Fisica, Universidade Federal do Parana, Curitiba, Parana (Brazil)

    2012-05-01

    In this work, porous ordered TiO{sub 2} films were prepared through sol gel route by using a monolayer of polystyrene spheres as template on indium-tin oxide/glass substrate. These films were characterized by SEM, AFM, Raman spectroscopy, UV-vis absorbance and XRD. The UV-vis absorbance spectrum show a pseudo band gap (PBG) with maxima at 460 nm arising from the light scattering and partial or total suppression of the photon density of states, this PBG can be controlled by the size of the pore. We also propose the use of this porous film as electron acceptor electrode in organic photovoltaic cells; we show that devices prepared with porous titania displayed higher efficiencies than devices using compact titania films as electrode. Such behaviour was observed in both bilayer and bulk heterojunction devices.

  19. Preparation of porous titanium oxide films onto indium tin oxide for application in organic photovoltaic devices

    International Nuclear Information System (INIS)

    Macedo, Andreia G.; Mattos, Luana L.; Spada, Edna R.; Serpa, Rafael B.; Campos, Cristiani S.; Grova, Isabel R.; Ackcelrud, Leni; Reis, Françoise T.; Sartorelli, Maria L.; Roman, Lucimara S.

    2012-01-01

    In this work, porous ordered TiO 2 films were prepared through sol gel route by using a monolayer of polystyrene spheres as template on indium-tin oxide/glass substrate. These films were characterized by SEM, AFM, Raman spectroscopy, UV-vis absorbance and XRD. The UV-vis absorbance spectrum show a pseudo band gap (PBG) with maxima at 460 nm arising from the light scattering and partial or total suppression of the photon density of states, this PBG can be controlled by the size of the pore. We also propose the use of this porous film as electron acceptor electrode in organic photovoltaic cells; we show that devices prepared with porous titania displayed higher efficiencies than devices using compact titania films as electrode. Such behaviour was observed in both bilayer and bulk heterojunction devices.

  20. Fabrication of nickel oxide and Ni-doped indium tin oxide thin films using pyrosol process

    International Nuclear Information System (INIS)

    Nakasa, Akihiko; Adachi, Mami; Usami, Hisanao; Suzuki, Eiji; Taniguchi, Yoshio

    2006-01-01

    Organic light emitting diodes (OLEDs) need indium tin oxide (ITO) anodes with highly smooth surface. The work function of ITO, about 4.8 eV, is generally rather lower than the optimum level for application to OLEDs. In this work, NiO was deposited by pyrosol process on pyrosol ITO film to increase the work function of the ITO for improving the performance of OLEDs. It was confirmed that NiO was successfully deposited on pyrosol ITO film and the NiO deposition increased the work function of pyrosol ITO, using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), atomic force microscopy (AFM) and atmospheric photoelectron spectroscopy. Furthermore, doping ITO with Ni succeeded in producing the Ni-doped ITO film with high work function and lower sheet resistance

  1. Thermally evaporated mechanically hard tin oxide thin films for opto-electronic apllications

    Energy Technology Data Exchange (ETDEWEB)

    Tripathy, Sumanta K.; Rajeswari, V. P. [Centre for Nano Science and Technology, GVP College of Engineering (Autonomous), Visakhapatnam- 530048 (India)

    2014-01-28

    Tungsten doped tin oxide (WTO) and Molybdenum doped tin oxide (MoTO) thin film were deposited on corn glass by thermal evaporation method. The films were annealed at 350°C for one hour. Structural analysis using Xray diffraction data shows both the films are polycrystalline in nature with monoclinic structure of tin oxide, Sn{sub 3}O{sub 4}, corresponding to JCPDS card number 01-078-6064. SEM photograph showed that both the films have spherical grains with size in the range of 20–30 nm. Compositional analysis was carried out using EDS which reveals the presence of Sn, O and the dopant Mo/W only thereby indicating the absence of any secondary phase in the films. The films are found to contain nearly 6 wt% of Mo, 8 wt% of W as dopants respectively. The transmission pattern for both the films in the spectral range 200 – 2000 nm shows that W doping gives a transparency of nearly 80% from 380 nm onwards while Mo doping has less transparency of 39% at 380nm. Film hardness measurement using Triboscope shows a film hardness of about 9–10 GPa for both the films. It indicates that W or M doping in tin oxide provides the films the added advantage of withstanding the mechanical wear and tear due to environmental fluctuations By optimizing the optical and electrical properties, W/Mo doped tin oxide films may be explored as window layers in opto-electronic applications such as solar cells.

  2. Cation vacancies and electrical compensation in Sb-doped thin-film SnO2 and ZnO

    International Nuclear Information System (INIS)

    Korhonen, E; Prozheeva, V; Tuomisto, F; Bierwagen, O; Speck, J S; White, M E; Galazka, Z; Liu, H; Izyumskaya, N; Avrutin, V; Özgür, Ü; Morkoç, H

    2015-01-01

    We present positron annihilation results on Sb-doped SnO 2 and ZnO thin films. The vacancy types and the effect of vacancies on the electrical properties of these intrinsically n-type transparent semiconducting oxides are studied. We find that in both materials low and moderate Sb-doping leads to formation of vacancy clusters of variable sizes. However, at high doping levels cation vacancy defects dominate the positron annihilation signal. These defects, when at sufficient concentrations, can efficiently compensate the n-type doping produced by Sb. This is the case in ZnO, but in SnO 2 the concentrations appear too low to cause significant compensation. (invited article)

  3. Cation vacancies and electrical compensation in Sb-doped thin-film SnO2 and ZnO

    Science.gov (United States)

    Korhonen, E.; Prozheeva, V.; Tuomisto, F.; Bierwagen, O.; Speck, J. S.; White, M. E.; Galazka, Z.; Liu, H.; Izyumskaya, N.; Avrutin, V.; Özgür, Ü.; Morkoç, H.

    2015-02-01

    We present positron annihilation results on Sb-doped SnO2 and ZnO thin films. The vacancy types and the effect of vacancies on the electrical properties of these intrinsically n-type transparent semiconducting oxides are studied. We find that in both materials low and moderate Sb-doping leads to formation of vacancy clusters of variable sizes. However, at high doping levels cation vacancy defects dominate the positron annihilation signal. These defects, when at sufficient concentrations, can efficiently compensate the n-type doping produced by Sb. This is the case in ZnO, but in SnO2 the concentrations appear too low to cause significant compensation.

  4. Synthesis of Nanocrystalline RuO2(60%)-SnO2(40%)Powders by Amorphous Citrate Route

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Nanometer RuO2-SnO2was synthesized by the citrate-gel method using RuCl3, SnCl4 as cation sources, citric acid as complexing agent and anhydrous ethanol as solvent. The structures of the derived powders were characterized by thermogravimetric and differential thermal analysis, X-ray diffraction, transmission electron microscope, and Brunauer-Emmett-Teller surface area measurement. The pure, fine and amorphous powders was obtained at 160℃. The materials calcined at above 400 ℃ were composed of rutile-type oxide phases having particle sizes of fairly narrow distribution and good thermal resistant properties. By adding SnO2 to RUO2, the Ru metallic phase can be effectively controlled under a traditional temperature of preparation for dimensional stable anode.

  5. Highly Sensitive and Selective Hydrogen Gas Sensor Using the Mesoporous SnO2 Modified Layers

    Directory of Open Access Journals (Sweden)

    Niuzi Xue

    2017-10-01

    Full Text Available It is important to improve the sensitivities and selectivities of metal oxide semiconductor (MOS gas sensors when they are used to monitor the state of hydrogen in aerospace industry and electronic field. In this paper, the ordered mesoporous SnO2 (m-SnO2 powders were prepared by sol-gel method, and the morphology and structure were characterized by X-ray diffraction analysis (XRD, transmission electron microscope (TEM and Brunauer–Emmett–Teller (BET. The gas sensors were fabricated using m-SnO2 as the modified layers on the surface of commercial SnO2 (c-SnO2 by screen printing technology, and tested for gas sensing towards ethanol, benzene and hydrogen with operating temperatures ranging from 200 °C to 400 °C. Higher sensitivity was achieved by using the modified m-SnO2 layers on the c-SnO2 gas sensor, and it was found that the S(c/m2 sensor exhibited the highest response (Ra/Rg = 22.2 to 1000 ppm hydrogen at 400 °C. In this paper, the mechanism of the sensitivity and selectivity improvement of the gas sensors is also discussed.

  6. SnO2*CoO ceramic obtained by microwave sintering

    International Nuclear Information System (INIS)

    Bordignon, M.A.N; Moura, F.; Zaghete, M.A.; Varela, J.A.; Perazolli, L.

    2009-01-01

    This work consists in the sintering study of CoO doped SnO 2 using microwave sintering oven and silicon carbide as a susceptor. The powders were obtained by dry oxides mixture and conformed in cylindrical shapes with 6mmx8mm and green density to 60%. Then the compacts were sintering up to 1.050 deg C, using heating rate of 50 deg C/min and isotherm up to 30min. The densities obtained were above 95% for both techniques. It was observed that occurred a temperature reducing of 400 deg C and time reducing of 210min to obtain the same densities, when was used the microwave oven without the phenomena of thermal runaway. So the sintered compacts were accomplished using DRX and SEM. It was made the electrical characterization (current x voltage) and it was found to have great potential in the production of dense ceramic-based SnO 2 with low resistivity to obtain electro-ceramic devices. (author)

  7. Antimony Doped Tin Oxides and Their Composites with Tin pyrophosphates as Catalyst Supports for Oxygen Evolution Reaction in Proton Exchange Membrane Water Electrolysis

    DEFF Research Database (Denmark)

    Xu, Junyuan; Li, Qingfeng; Christensen, Erik

    2012-01-01

    Proton exchange membrane water electrolysers operating at typically 80 °C or at further elevated temperatures suffer from insufficient catalyst activity and durability. In this work, antimony doped tin oxide nanoparticles were synthesized and further doped with an inorganic proton conducting phase...... based on tin pyrophosphates as the catalyst support. The materials showed an overall conductivity of 0.57 S cm−1 at 130 °C under the water vapor atmosphere with a contribution of the proton conduction. Using this composite support, iridium oxide nanoparticle catalysts were prepared and characterized...

  8. Preparation of MnO2 electrodes coated by Sb-doped SnO2 and their effect on electrochemical performance for supercapacitor

    International Nuclear Information System (INIS)

    Zhang, Yuqing; Mo, Yan

    2014-01-01

    Highlights: • Sb-doped SnO 2 coated MnO 2 electrodes (SS-MnO 2 electrodes) are prepared. • The capacitive property and stability of SS-MnO 2 electrode is superior to uncoated MnO 2 electrode and SnO 2 coated MnO 2 electrode. • Sb-doped SnO 2 coating enhances electrochemical performance of MnO 2 effectively. • SS-MnO 2 electrodes are desirable to become a novel electrode material for supercapacitor. - Abstract: To enhance the specific capacity and cycling stability of manganese binoxide (MnO 2 ) for supercapacitor, antimony (Sb) doped tin dioxide (SnO 2 ) is coated on MnO 2 through a sol-gel method to prepare MnO 2 electrodes, enhancing the electrochemical performance of MnO 2 electrode in sodium sulfate electrolytes. The structure and composition of SS-MnO 2 electrode are characterized by using scanning electron microscope (SEM), transmission electron microscope (TEM), Fourier transform infrared spectroscopy (FT-IR) and X-Ray diffraction spectroscopy (XRD). The electrochemical performances are evaluated and researched by galvanostatic charge-discharge test, cyclic voltammogram (CV) and electrochemical impedance spectroscopy (EIS). The results show that SS-MnO 2 electrodes hold porous structure, displaying superior cycling stability at large current work condition in charge-discharge tests and good capacity performance at high scanning rate in CV tests. The results of EIS show that SS-MnO 2 electrodes have small internal resistance. Therefore, the electrochemical performances of MnO 2 electrodes are enhanced effectively by Sb-doped SnO 2 coating

  9. Characterization of tin dioxide film for chemical vapors sensor

    International Nuclear Information System (INIS)

    Hafaiedh, I.; Helali, S.; Cherif, K.; Abdelghani, A.; Tournier, G.

    2008-01-01

    Recently, oxide semiconductor material used as transducer has been the central topic of many studies for gas sensor. In this paper we investigated the characteristic of a thick film of tin dioxide (SnO 2 ) film for chemical vapor sensor. It has been prepared by screen-printing technology and deposited on alumina substrate provided with two gold electrodes. The morphology, the molecular composition and the electrical properties of this material have been characterized respectively by Atomic Force Spectroscopy (AFM), Fourier Transformed Infrared Spectroscopy (FTIR) and Impedance Spectroscopy (IS). The electrical properties showed a resistive behaviour of this material less than 300 deg. C which is the operating temperature of the sensor. The developed sensor can identify the nature of the detected gas, oxidizing or reducing

  10. Synergy Effects of the Mixture of Bismuth Molybdate Catalysts with SnO2/ZrO2/MgO in Selective Propene Oxidation and the Connection between Conductivity and Catalytic Activity

    DEFF Research Database (Denmark)

    Le, Minh Thang; Do, Van Hung; Truong, Duc Duc

    2016-01-01

    Bismuth molybdate catalysts have been used for partial oxidation and ammoxidation of light hydrocarbons since the 1950s. In particular, there is the synergy effect (the enhancement of the catalytic activity in the catalysts mixed from different components) in different phases of bismuth molybdate...... catalysts which has been observed and studied since the 1980s; however, despite it being interpreted differently by different research groups, there is still no decisive conclusion on the origin of the synergy effect that has been obtained. The starting idea of this work is to find an answer......, impregnation, and sol-gel methods. The mixtures were characterized by XRD, BET, XPS, and EDX techniques to determine the phase composition and surface properties. The conductivities of these samples were recorded at the catalytic reaction temperature (300-450 degrees C). Comparison of the catalytic activities...

  11. Assembly of ZIF-67 Metal-Organic Framework over Tin Oxide Nanoparticles for Synergistic Chemiresistive CO2 Gas Sensing.

    Science.gov (United States)

    DMello, Marilyn Esclance; Sundaram, Nalini G; Kalidindi, Suresh Babu

    2018-05-03

    Metal-organic frameworks (MOFs) are widely known for their record storage capacities of small gas molecules (H 2 , CO 2 , and CH 4 ). Assembly of such porous materials onto well-known chemiresistive gas sensing elements such as SnO 2 could be an attractive prospect to achieve novel sensing properties as this affects the surface chemistry of SnO 2 . Cobalt-imidazole based ZIF-67 MOF was grown onto preformed SnO 2 nanoparticles to realize core-shell like architecture and explored for greenhouse gas CO 2 sensing. CO 2 sensing over SnO 2 is a challenge because its interaction with SnO 2 surface is minimal. The ZIF-67 coating over SnO 2 improved the response of SnO 2 up to 12-fold (for 50 % CO 2 ). The SnO 2 @ZIF-67 also showed a response of 16.5±2.1 % for 5000 ppm CO 2 (threshold limit value (TLV)) at 205 °C, one of the best values reported for a SnO 2 -based sensor. The observed novel CO 2 sensing characteristics are assigned to electronic structure changes at the interface of ZIF-67 and SnO 2 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. SnO2/carbon nanotube nanocomposites synthesized in supercritical fluids: highly efficient materials for use as a chemical sensor and as the anode of a lithium-ion battery

    International Nuclear Information System (INIS)

    An Guimin; Na Na; Zhang Xinrong; Miao Zhenjiang; Miao Shiding; Ding Kunlun; Liu Zhimin

    2007-01-01

    SnO 2 /multi-walled carbon nanotube (MWCNT) nanocomposites were prepared via oxidation of SnCl 2 in a supercritical CO 2 -methanol mixture containing MWCNTs. The as-prepared nanocomposites were characterized by means of x-ray diffraction, x-ray photoelectron spectroscopy, and transmission electron microscopy. It was indicated that SnO 2 nanoparticles with size of 3-5 nm were uniformly and tightly decorated on the MWCNTs. The chemiluminescence characteristic to H 2 S and electrochemical performance of the as-prepared SnO 2 /MWCNT composites were investigated. The SnO 2 /MWCNT composites exhibited extremely high efficiency for detecting H 2 S, and also displayed good electrochemical performance as the anode material in a lithium-ion battery

  13. An oxidation-resistant indium tin oxide catalyst support for proton exchange membrane fuel cells

    Energy Technology Data Exchange (ETDEWEB)

    Chhina, H.; Campbell, S. [Ballard Power Systems Inc., 9000 Glenlyon Parkway, Burnaby, BC V5J 5J8 (Canada); Kesler, O. [Department of Mechanical Engineering, University of British Columbia, Vancouver, BC, V6T 1Z4 (Canada)

    2006-10-27

    The oxidation of carbon catalyst supports causes degradation in catalyst performance in proton exchange membrane fuel cells (PEMFCs). Indium tin oxide (ITO) is considered as a candidate for an alternative catalyst support. The electrochemical stability of ITO was studied by use of a rotating disk electrode (RDE). Oxidation cycles between +0.6 and +1.8V were applied to ITO supporting a Pt catalyst. Cyclic voltammograms (CVs) both before and after the oxidation cycles were obtained for Pt on ITO, Hispec 4000 (a commercially available catalyst), and 40wt.% Pt dispersed in-house on Vulcan XC-72R. Pt on ITO showed significantly better electrochemical stability, as determined by the relative change in electrochemically active surface area after cycling. Hydrogen desorption peaks in the CVs existed even after 100 cycles from 0.6 to 1.8V for Pt on ITO. On the other hand, most of the active surface area was lost after 100 cycles of the Hispec 4000 catalyst. The 40wt.% Pt on Vulcan made in-house also lost most of its active area after only 50 cycles. Pt on ITO was significantly more electrochemically stable than both Hispec 4000 and Pt on Vulcan XC-72R. In this study, it was found that the Pt on ITO had average crystallite sizes of 13nm for Pt and 38nm for ITO. Pt on ITO showed extremely high thermal stability, with only {approx}1wt.% loss of material for ITO versus {approx}57wt.% for Hispec 4000 on heating to 1000{sup o}C. The TEM data show Pt clusters dispersed on small crystalline ITO particles. The SEM data show octahedral shaped ITO particles supporting Pt. (author)

  14. On exceeding the solubility limit of Cr+3 dopants in SnO2 nanoparticles based dilute magnetic semiconductors

    Science.gov (United States)

    URS, Kusuma; Bhat, S. V.; Kamble, Vinayak

    2018-04-01

    The paper investigates the magnetic behavior of chromium doped SnO2 Dilute Magnetic Semiconductor (DMS) nanoparticles, through structural, spectroscopic, and magnetic studies. A non-equilibrium solution combustion method is adopted to synthesize 0-5 at. % Cr doped SnO2 nanoparticles. The detailed spectroscopic studies on the system using micro-Raman spectroscopy, x-ray photoelectron spectroscopy, and electron paramagnetic resonance spectroscopy along with the structural analysis confirm the presence of Cr in 3+ oxidation state, which substitutes at Sn4+ site in SnO6 octahedra of the rutile structure. This doping is found to enhance the defects in the system, i.e., oxygen vacancies. All the synthesized SnO2 nanoparticles (with or without dopants) are found to exhibit Room Temperature Ferromagnetism (RTFM). This occurrence of RTFM is attributed to the magnetic exchange interaction through F-centers of oxygen vacancies as well as dopant magnetic impurities and explained through the Bound Magnetic Polaron (BMP) model of DMS systems. Nonetheless, as the doping of Cr is further increased beyond 2%, the solubility limit is achieved. This antiferromagnetic exchange interaction from interstitial Cr dopants dominates over the BMP mechanism and, hence, leads to the decrease in the net magnetic moment drastically.

  15. Partial oxidation of TiN coating by hydrothermal treatment and ozone treatment to improve its osteoconductivity

    International Nuclear Information System (INIS)

    Shi, Xingling; Xu, Lingli; Le, Thi Bang; Zhou, Guanghong; Zheng, Chuanbo; Tsuru, Kanji; Ishikawa, Kunio

    2016-01-01

    Dental implants made of pure titanium suffer from abrasion and scratch during routine oral hygiene procedures. This results in an irreversible surface damage, facilitates bacteria adhesion and increases risk of peri-implantitis. To overcome these problems, titanium nitride (TiN) coating was introduced to increase surface hardness of pure titanium. However, the osteoconductivity of TiN is considered to be similar or superior to that of titanium and its alloys and therefore surface modification is necessary. In this study, TiN coating prepared through gas nitriding was partially oxidized by hydrothermal (HT) treatment and ozone (O 3 ) treatment in pure water to improve its osteoconductivity. The effects of HT treatment and O 3 treatment on surface properties of TiN were investigated and the osteoconductivity after undergoing treatment was assessed in vitro using osteoblast evaluation. The results showed that the critical temperature for HT treatment was 100 °C since higher temperatures would impair the hardness of TiN coating. By contrast, O 3 treatment was more effective in oxidizing TiN surfaces, improving its wettability while preserving its morphology and hardness. Osteoblast attachment, proliferation, alkaline phosphatase (ALP) expression and mineralization were improved on oxidized specimens, especially on O 3 treated specimens, compared with untreated ones. These effects seemed to be consequences of partial oxidation, as well as improved hydrophilicity and surface decontamination. Finally, it was concluded that, partially oxidized TiN is a promising coating to be used for dental implant. - Highlights: • TiN coating surface was oxidized by hydrothermal or ozone treatment while preserving its hardness. • Improved wettability, decontamination and interstitial N promoted osteoblast responses. • Partial oxidation makes TiN a promising coating for dental implant with good osteoconductivity.

  16. Partial oxidation of TiN coating by hydrothermal treatment and ozone treatment to improve its osteoconductivity

    Energy Technology Data Exchange (ETDEWEB)

    Shi, Xingling [School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Department of Biomaterials, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582 (Japan); Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huaian 223003 (China); Xu, Lingli, E-mail: linly311@163.com [School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Le, Thi Bang [Department of Mechanical Engineering, University of Malaya, 50603 Kuala Lumpur (Malaysia); Zhou, Guanghong [Jiangsu Provincial Key Laboratory for Interventional Medical Devices, Huaiyin Institute of Technology, Huaian 223003 (China); Zheng, Chuanbo, E-mail: zjust316@163.com [School of Material Science and Engineering, Jiangsu University of Science and Technology, Zhenjiang 212003 (China); Tsuru, Kanji; Ishikawa, Kunio [Department of Biomaterials, Faculty of Dental Science, Kyushu University, Fukuoka 812-8582 (Japan)

    2016-02-01

    Dental implants made of pure titanium suffer from abrasion and scratch during routine oral hygiene procedures. This results in an irreversible surface damage, facilitates bacteria adhesion and increases risk of peri-implantitis. To overcome these problems, titanium nitride (TiN) coating was introduced to increase surface hardness of pure titanium. However, the osteoconductivity of TiN is considered to be similar or superior to that of titanium and its alloys and therefore surface modification is necessary. In this study, TiN coating prepared through gas nitriding was partially oxidized by hydrothermal (HT) treatment and ozone (O{sub 3}) treatment in pure water to improve its osteoconductivity. The effects of HT treatment and O{sub 3} treatment on surface properties of TiN were investigated and the osteoconductivity after undergoing treatment was assessed in vitro using osteoblast evaluation. The results showed that the critical temperature for HT treatment was 100 °C since higher temperatures would impair the hardness of TiN coating. By contrast, O{sub 3} treatment was more effective in oxidizing TiN surfaces, improving its wettability while preserving its morphology and hardness. Osteoblast attachment, proliferation, alkaline phosphatase (ALP) expression and mineralization were improved on oxidized specimens, especially on O{sub 3} treated specimens, compared with untreated ones. These effects seemed to be consequences of partial oxidation, as well as improved hydrophilicity and surface decontamination. Finally, it was concluded that, partially oxidized TiN is a promising coating to be used for dental implant. - Highlights: • TiN coating surface was oxidized by hydrothermal or ozone treatment while preserving its hardness. • Improved wettability, decontamination and interstitial N promoted osteoblast responses. • Partial oxidation makes TiN a promising coating for dental implant with good osteoconductivity.

  17. Deposition efficiency in the preparation of ozone-producing nickel and antimony doped tin oxide anodes

    Directory of Open Access Journals (Sweden)

    Staffan Sandin

    2017-03-01

    Full Text Available The influence of precursor salts in the synthesis of nickel and antimony doped tin oxide (NATO electrodes using thermal decomposition from dissolved chloride salts was investigated. The salts investigated were SnCl4×5H2O, SnCl2×2H2O, SbCl3 and NiCl2×6H2O. It was shown that the use of SnCl4×5H20 in the preparation process leads to a tin loss of more than 85 %. The loss of Sb can be as high as 90 % while no indications of Ni loss was observed. As a consequence, the concentration of Ni in the NATO coating will be much higher than in the precursor solution. This high and uncontrolled loss of precursors during the preparation process will lead to an unpredictable composition in the NATO coating and will have negative economic and environmental effects. It was found that using SnCl2×2H20 instead of SnCl4×5H2O can reduce the tin loss to less than 50 %. This tin loss occurs at higher temperatures than when using SnCl4×5H2O where the tin loss occurs from 56 – 147 °C causing the composition to change both during the drying (80 – 110 °C and calcination (460 -550 °C steps of the preparation process. Electrodes coated with NATO based on the two different tin salts were investigated for morphology, composition, structure, and ozone electrocatalytic properties.

  18. Confined SnO2 quantum-dot clusters in graphene sheets as high-performance anodes for lithium-ion batteries.

    Science.gov (United States)

    Zhu, Chengling; Zhu, Shenmin; Zhang, Kai; Hui, Zeyu; Pan, Hui; Chen, Zhixin; Li, Yao; Zhang, Di; Wang, Da-Wei

    2016-05-16

    Construction of metal oxide nanoparticles as anodes is of special interest for next-generation lithium-ion batteries. The main challenge lies in their rapid capacity fading caused by the structural degradation and instability of solid-electrolyte interphase (SEI) layer during charge/discharge process. Herein, we address these problems by constructing a novel-structured SnO2-based anode. The novel structure consists of mesoporous clusters of SnO2 quantum dots (SnO2 QDs), which are wrapped with reduced graphene oxide (RGO) sheets. The mesopores inside the clusters provide enough room for the expansion and contraction of SnO2 QDs during charge/discharge process while the integral structure of the clusters can be maintained. The wrapping RGO sheets act as electrolyte barrier and conductive reinforcement. When used as an anode, the resultant composite (MQDC-SnO2/RGO) shows an extremely high reversible capacity of 924 mAh g(-1) after 200 cycles at 100 mA g(-1), superior capacity retention (96%), and outstanding rate performance (505 mAh g(-1) after 1000 cycles at 1000 mA g(-1)). Importantly, the materials can be easily scaled up under mild conditions. Our findings pave a new way for the development of metal oxide towards enhanced lithium storage performance.

  19. Confined SnO2 quantum-dot clusters in graphene sheets as high-performance anodes for lithium-ion batteries

    Science.gov (United States)

    Zhu, Chengling; Zhu, Shenmin; Zhang, Kai; Hui, Zeyu; Pan, Hui; Chen, Zhixin; Li, Yao; Zhang, Di; Wang, Da-Wei

    2016-01-01

    Construction of metal oxide nanoparticles as anodes is of special interest for next-generation lithium-ion batteries. The main challenge lies in their rapid capacity fading caused by the structural degradation and instability of solid-electrolyte interphase (SEI) layer during charge/discharge process. Herein, we address these problems by constructing a novel-structured SnO2-based anode. The novel structure consists of mesoporous clusters of SnO2 quantum dots (SnO2 QDs), which are wrapped with reduced graphene oxide (RGO) sheets. The mesopores inside the clusters provide enough room for the expansion and contraction of SnO2 QDs during charge/discharge process while the integral structure of the clusters can be maintained. The wrapping RGO sheets act as electrolyte barrier and conductive reinforcement. When used as an anode, the resultant composite (MQDC-SnO2/RGO) shows an extremely high reversible capacity of 924 mAh g−1 after 200 cycles at 100 mA g−1, superior capacity retention (96%), and outstanding rate performance (505 mAh g−1 after 1000 cycles at 1000 mA g−1). Importantly, the materials can be easily scaled up under mild conditions. Our findings pave a new way for the development of metal oxide towards enhanced lithium storage performance. PMID:27181691

  20. Inkjet printed ambipolar transistors and inverters based on carbon nanotube/zinc tin oxide heterostructures

    International Nuclear Information System (INIS)

    Kim, Bongjun; Jang, Seonpil; Dodabalapur, Ananth; Geier, Michael L.; Prabhumirashi, Pradyumna L.; Hersam, Mark C.

    2014-01-01

    We report ambipolar field-effect transistors (FETs) consisting of inkjet printed semiconductor bilayer heterostructures utilizing semiconducting single-walled carbon nanotubes (SWCNTs) and amorphous zinc tin oxide (ZTO). The bilayer structure allows for electron transport to occur principally in the amorphous oxide layer and hole transport to occur exclusively in the SWCNT layer. This results in balanced electron and hole mobilities exceeding 2 cm 2 V −1 s −1 at low operating voltages ( 10). This work provides a pathway for realizing solution processable, inkjet printable, large area electronic devices, and systems based on SWCNT-amorphous oxide heterostructures

  1. Study on the intrinsic defects in tin oxide with first-principles method

    Science.gov (United States)

    Sun, Yu; Liu, Tingyu; Chang, Qiuxiang; Ma, Changmin

    2018-04-01

    First-principles and thermodynamic methods are used to study the contribution of vibrational entropy to defect formation energy and the stability of the intrinsic point defects in SnO2 crystal. According to thermodynamic calculation results, the contribution of vibrational entropy to defect formation energy is significant and should not be neglected, especially at high temperatures. The calculated results indicate that the oxygen vacancy is the major point defect in undoped SnO2 crystal, which has a higher concentration than that of the other point defect. The property of negative-U is put forward in SnO2 crystal. In order to determine the most stable defects much clearer under different conditions, the most stable intrinsic defect as a function of Fermi level, oxygen partial pressure and temperature are described in the three-dimensional defect formation enthalpy diagrams. The diagram visually provides the most stable point defects under different conditions.

  2. Impact of soft annealing on the performance of solution-processed amorphous zinc tin oxide thin-film transistors

    KAUST Repository

    Nayak, Pradipta K.; Hedhili, Mohamed N.; Cha, Dong Kyu; Alshareef, Husam N.

    2013-01-01

    It is demonstrated that soft annealing duration strongly affects the performance of solution-processed amorphous zinc tin oxide thin-film transistors. Prolonged soft annealing times are found to induce two important changes in the device: (i) a

  3. Zinc tin oxide as high-temperature stable recombination layer for mesoscopic perovskite/silicon monolithic tandem solar cells

    KAUST Repository

    Werner, Jé ré mie; Walter, Arnaud; Rucavado, Esteban; Moon, Soo Jin; Sacchetto, Davide; Rienaecker, Michael; Peibst, Robby; Brendel, Rolf; Niquille, Xavier; De Wolf, Stefaan; Lö per, Philipp; Morales-Masis, Monica; Nicolay, Sylvain; Niesen, Bjoern; Ballif, Christophe

    2016-01-01

    the concept, we fabricate monolithic tandem cells with mesoscopic top cell with up to 16% efficiency. We then investigate the effect of zinc tin oxide layer thickness variation, showing a strong influence on the optical interference pattern within the tandem

  4. A novel electrode surface fabricated by directly attaching gold nanoparticles onto NH2+ ions implanted-indium tin oxide substrate

    International Nuclear Information System (INIS)

    Liu Chenyao; Jiao Jiao; Chen Qunxia; Xia Ji; Li Shuoqi; Hu Jingbo; Li Qilong

    2010-01-01

    A new type of gold nanoparticle attached to a NH 2 + ion implanted-indium tin oxide surface was fabricated without using peculiar binder molecules, such as 3-(aminopropyl)-trimethoxysilane. A NH 2 /indium tin oxide film was obtained by implantation at an energy of 80 keV with a fluence of 5 x 10 15 ions/cm 2 . The gold nanoparticle-modified film was characterized by X-ray photoelectron spectroscopy, scanning electron microscopy and electrochemical techniques and compared with a modified bare indium tin oxide surface and 3-(aminopropyl)-trimethoxysilane linked surface, which exhibited a relatively low electron transfer resistance and high electrocatalytic activity. The results demonstrate that NH 2 + ion implanted-indium tin oxide films can provide an important route to immobilize nanoparticles, which is attractive in developing new biomaterials.

  5. Prediction of crack density and electrical resistance changes in indium tin oxide/polymer thin films under tensile loading

    KAUST Repository

    Mora Cordova, Angel; Khan, Kamran; El Sayed, Tamer

    2014-01-01

    We present unified predictions for the crack onset strain, evolution of crack density, and changes in electrical resistance in indium tin oxide/polymer thin films under tensile loading. We propose a damage mechanics model to quantify and predict

  6. Epitaxy-enabled vapor-liquid-solid growth of tin-doped indium oxide nanowires with controlled orientations

    KAUST Repository

    Shen, Youde; Turner, Stuart G.; Yang, Ping; Van Tendeloo, Gustaaf; Lebedev, Oleg I.; Wu, Tao

    2014-01-01

    challenges in reliably achieving these goals of orientation-controlled nanowire synthesis and assembly. Here we report that growth of planar, vertical and randomly oriented tin-doped indium oxide (ITO) nanowires can be realized on yttria-stabilized zirconia

  7. Chemical Vapor Identification by Plasma Treated Thick Film Tin Oxide Gas Sensor Array and Pattern Recognition

    Directory of Open Access Journals (Sweden)

    J. K. Srivastava

    2011-02-01

    Full Text Available Present study deals the class recognition potential of a four element plasma treated thick film tin oxide gas sensor array exposed with volatile organic compounds (VOCs. Methanol, Ethanol and Acetone are selected as target VOCs and exposed on sensor array at different concentration in range from 100-1000 ppm. Sensor array consist of four tin oxide sensors doped with 1-4 % PbO concentrations were fabricated by thick film technology and then treated with oxygen plasma for 5-10 minute durations. Sensor signal is analyzed by principal component analysis (PCA for visual classification of VOCs. Further output of PCA is used as input for classification of VOCs by four pattern classification techniques as: linear discriminant analysis (LDA, k-nearest neighbor (KNN, back propagation neural network (BPNN and support vector machine (SVM. All the four classifier results 100 % correct classification rate of VOCs by response analysis of sensor array treated with plasma for 5 minute.

  8. Structural, optical and electrical properties of indium tin oxide thin films prepared by spray pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Benamar, E.; Rami, M.; Messaoudi, C.; Sayah, D.; Ennaoui, A. [Deptartmento de Physique, Laboratoire de Physique des Materiaux, Faculte des Sciences, BP 1014, Ave Inb Battouta, Rabat (Morocco)

    1998-11-27

    Spray pyrolysis process has been used to deposit highly transparent and conducting films of tin-doped indium oxide onto glass substrates. The electrical, structural and optical properties have been investigated as a function of various deposition parameters namely dopant concentrations, temperature and nature of substrate. The morphology of the surface as a function of the substrate temperature has been studied using atomic force microscopy. XRD has shown that deposited films are polycrystalline without second phases and have a preferred orientation (4 0 0). Indium tin oxide layers with low resistivity values around 4x10{sup -5} {Omega} cm and transmission coefficients in the visible and near-infrared range of about 85-90% have been easily obtained

  9. Hydrogen plasma treatment for improved conductivity in amorphous aluminum doped zinc tin oxide thin films

    Directory of Open Access Journals (Sweden)

    M. Morales-Masis

    2014-09-01

    Full Text Available Improving the conductivity of earth-abundant transparent conductive oxides (TCOs remains an important challenge that will facilitate the replacement of indium-based TCOs. Here, we show that a hydrogen (H2-plasma post-deposition treatment improves the conductivity of amorphous aluminum-doped zinc tin oxide while retaining its low optical absorption. We found that the H2-plasma treatment performed at a substrate temperature of 50 °C reduces the resistivity of the films by 57% and increases the absorptance by only 2%. Additionally, the low substrate temperature delays the known formation of tin particles with the plasma and it allows the application of the process to temperature-sensitive substrates.

  10. Hydrogen plasma treatment for improved conductivity in amorphous aluminum doped zinc tin oxide thin films

    Energy Technology Data Exchange (ETDEWEB)

    Morales-Masis, M., E-mail: monica.moralesmasis@epfl.ch; Ding, L.; Dauzou, F. [Photovoltaics and Thin-Film Electronics Laboratory (PVLab), Institute of Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne - EPFL, Rue de la Maladière 71b, CH-2002 Neuchatel (Switzerland); Jeangros, Q. [Interdisciplinary Centre for Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Hessler-Wyser, A. [Photovoltaics and Thin-Film Electronics Laboratory (PVLab), Institute of Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne - EPFL, Rue de la Maladière 71b, CH-2002 Neuchatel (Switzerland); Interdisciplinary Centre for Electron Microscopy, Ecole Polytechnique Fédérale de Lausanne (EPFL), Lausanne (Switzerland); Nicolay, S. [Centre Suisse d’Electronique et de Microtechnique (CSEM) SA, Rue Jaquet-Droz 1, CH-2002 Neuchatel (Switzerland); Ballif, C. [Photovoltaics and Thin-Film Electronics Laboratory (PVLab), Institute of Microengineering (IMT), Ecole Polytechnique Fédérale de Lausanne - EPFL, Rue de la Maladière 71b, CH-2002 Neuchatel (Switzerland); Centre Suisse d’Electronique et de Microtechnique (CSEM) SA, Rue Jaquet-Droz 1, CH-2002 Neuchatel (Switzerland)

    2014-09-01

    Improving the conductivity of earth-abundant transparent conductive oxides (TCOs) remains an important challenge that will facilitate the replacement of indium-based TCOs. Here, we show that a hydrogen (H{sub 2})-plasma post-deposition treatment improves the conductivity of amorphous aluminum-doped zinc tin oxide while retaining its low optical absorption. We found that the H{sub 2}-plasma treatment performed at a substrate temperature of 50 °C reduces the resistivity of the films by 57% and increases the absorptance by only 2%. Additionally, the low substrate temperature delays the known formation of tin particles with the plasma and it allows the application of the process to temperature-sensitive substrates.

  11. Size-controlled synthesis of SnO2 quantum dots and their gas-sensing performance

    Science.gov (United States)

    Du, Jianping; Zhao, Ruihua; Xie, Yajuan; Li, Jinping

    2015-08-01

    Tin dioxide quantum dots (TQDs) with controllable size were synthesized by changing the amount of alkaline reagent in the hydrothermal process. The gas-sensing properties were investigated by operating chemoresistor type sensor. The morphology and structure were characterized by X-ray diffraction, scanning/transmission electron microscopy, UV-vis and Raman spectrometry. The as-synthesized SnO2 shows the characteristics of quantum dots and the narrowest size distribution is about 2-3 nm. The gas-sensing results indicate that the responses are strongly dependent on the size of quantum dots. TQDs with different sizes exhibit different sensitivities and selectivities to volatile toxic chemicals such as aldehyde, acetone, methanol, ethanol and amine. Especially, when the sensors are exposed to 100 ppm triethylamine (TEA), the sensing response value of TQDs with small size is two times higher than that of the large-size TQDs. The maximum response values of TQDs to 1 ppm and 100 ppm TEA are 15 and 153, respectively. The response time is 1 s and the recovery time is 47 s upon exposure to 1 ppm TEA. The results suggest that it is an effective method by regulating the size of SnO2 quantum dots to detect low-concentration hazardous volatile compounds.

  12. Optical second harmonic generation phase measurement at interfaces of some organic layers with indium tin oxide

    Science.gov (United States)

    Ngah Demon, Siti Zulaikha; Miyauchi, Yoshihiro; Mizutani, Goro; Matsushima, Toshinori; Murata, Hideyuki

    2014-08-01

    We observed phase shift in optical second harmonic generation (SHG) from interfaces of indium tin oxide (ITO)/copper phthalocyanine (CuPc) and ITO/pentacene. Phase correction due to Fresnel factors of the sample was taken into account. The phase of SHG electric field at the ITO/pentacene interface, ϕinterface with respect to the phase of SHG of bare substrate ITO was 160°, while the interface of ITO/CuPc had a phase of 140°.

  13. Optical second harmonic generation phase measurement at interfaces of some organic layers with indium tin oxide

    OpenAIRE

    Ngah Demon, Siti Zulaikha; Miyauchi, Yoshihiro; Mizutani, Goro; Matsushima, Toshinori; Murata, Hideyuki

    2014-01-01

    We observed phase shift in optical second harmonic generation (SHG) from interfaces of indium tin oxide (ITO)/copper phthalocyanine (CuPc) and ITO/pentacene. Phase correction due to Fresnel factors of the sample was taken into account. The phase of SHG electric field at the ITO/pentacene interface, ϕ_ with respect to the phase of SHG of bare substrate ITO was 160°, while the interface of ITO/CuPc had a phase of 140°.

  14. Alkaline earth metal doped tin oxide as a novel oxygen storage material

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Qiang, E-mail: dong@tagen.tohoku.ac.jp [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku Sendai 980-8577 (Japan); Yin, Shu; Yoshida, Mizuki; Wu, Xiaoyong; Liu, Bin [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku Sendai 980-8577 (Japan); Miura, Akira; Takei, Takahiro; Kumada, Nobuhiro [Department of Research Interdisciplinary Graduate School of Medicine and Engineering, University of Yamanashi, Miyamae cho-7, Kofu 400-8511 (Japan); Sato, Tsugio [Institute of Multidisciplinary Research for Advanced Materials, Tohoku University, 2-1-1 Katahira, Aoba-ku Sendai 980-8577 (Japan)

    2015-09-15

    Alkaline earth metal doped tin oxide (SnO{sub 2}) hollow nanospheres with a diameter of 50 nm have been synthesized successfully via a facial solvothermal route in a very simple system composed of only ethanol, acetic acid, SnCl{sub 4}·5H{sub 2}O and A(NO{sub 3}){sub 2}·xH{sub 2}O (A = Mg, Ca, Sr, Ba). The synthesized undoped SnO{sub 2} and A-doped SnO{sub 2} hollow nanospheres were characterized by the oxygen storage capacity (OSC), X-ray diffraction, transmission electron microscopy and the Brunauer–Emmet–Teller (BET) technique. The OSC values of all samples were measured using thermogravimetric-differential thermal analysis. The incorporation of alkaline earth metal ion into tin oxide greatly enhanced the thermal stability and OSC. Especially, Ba-doped SnO{sub 2} hollow nanospheres calcined at 1000 °C for 20 h with a BET surface area of 61 m{sup 2} g{sup −1} exhibited the considerably high OSC of 457 μmol-O g{sup −1} and good thermal stability. Alkaline earth metal doped tin oxide has the potential to be a novel oxygen storage material.

  15. The role of electric field during spray deposition on fluorine doped tin oxide film

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Anuj, E-mail: anujkumarom@gmail.com; Swami, Sanjay Kumar; Dutta, Viresh

    2014-03-05

    Highlights: • Fluorine doped tin oxide deposition by spray technique. • The growth reaction of tin oxide, controlled by the electric field on the substrate surface. • Deposit on large scale substrate 10 cm × 10 cm by single nozzle. • Obtained good quality of thin film. -- Abstract: The fluorine doped tin oxide film has been deposited on 10 cm × 10 cm glass substrate by using spray technique with a voltage applied between the nozzle and an annular electrode placed 2 mm below the nozzle. The effect of the electric field thus created during the spray deposition on structural, optical and electrical properties of SnO{sub 2}:F (FTO) film was studied. X-ray diffraction pattern revealed the presence of cassiterite structure with (2 0 0) orientation for all the FTO film. SEM study revealed the formation of smooth and uniform surface FTO film under the electric field over the entire substrate area. The electrical measurements show that the film prepared under the electric field (for an applied voltage of 2000 V) had a resistivity ∼1.2 × 10{sup −3} Ω cm, carrier concentration ∼4.21 × 10{sup 20} cm{sup −3} and mobility ∼14.48 cm{sup 2} V{sup −1} s{sup −1}. The sprayed FTO film have the average transmission in the visible region of more than about 80%.

  16. Microwave-Hydrothermal Synthesis of SnO2-CNTs Hybrid Nanocomposites with Visible Light Photocatalytic Activity.

    Science.gov (United States)

    Wu, Shuisheng; Dai, Weili

    2017-03-03

    SnO2 nanoparticles coated on carbon nanotubes (CNTs) were prepared via a simple microwave-hydrothermal route. The as-obtained SnO2-CNTs composites were characterized using X-ray powder diffraction, Raman spectroscopy, and transmission electron microscopy. The photocatalytic activity of as-prepared SnO2-CNTs for degradation of Rhodamine B under visible light irradiation was investigated. The results show that SnO2-CNTs nanocomposites have a higher photocatalytic activity than pure SnO2 due to the rapid transferring of electrons and the effective separation of holes and electrons on SnO2-CNTs.

  17. Construction of SnO2-Graphene Composite with Half-Supported Cluster Structure as Anode toward Superior Lithium Storage Properties.

    Science.gov (United States)

    Zhu, Chengling; Chen, Zhixin; Zhu, Shenmin; Li, Yao; Pan, Hui; Meng, Xin; Imtiaz, Muhammad; Zhang, Di

    2017-06-12

    Inspired by nature, herein we designed a novel construction of SnO 2 anodes with an extremely high lithium storage performance. By utilizing small sheets of graphene oxide, the partitioned-pomegranate-like structure was constructed (SnO 2 @C@half-rGO), in which the porous clusters of SnO 2 nanoparticles are partially supported by reduced graphene oxide sheets while the rest part is exposed (half-supported), like partitioned pomegranates. When served as anode for lithium-ion batteries, SnO 2 @C@half-rGO exhibited considerably high specific capacity (1034.5 mAh g -1 after 200 cycles at 100 mA g -1 ), superior rate performance and remarkable durability (370.3 mAh g -1 after 10000 cycles at 5 A g -1 ). When coupled with graphitized porous carbon cathode for lithium-ion hybrid capacitors, the fabricated devices delivered a high energy density of 257 Wh kg -1 at ∼200 W kg -1 and maintained 79 Wh kg -1 at a super-high power density of ∼20 kW kg -1 within a wide voltage window up to 4 V. This facile and scalable approach demonstrates a new architecture for graphene-based composite for practical use in energy storage with high performance.

  18. Parts per billion-level detection of benzene using SnO2/graphene nanocomposite composed of sub-6 nm SnO2 nanoparticles.

    Science.gov (United States)

    Meng, Fan-Li; Li, Hui-Hua; Kong, Ling-Tao; Liu, Jin-Yun; Jin, Zhen; Li, Wei; Jia, Yong; Liu, Jin-Huai; Huang, Xing-Jiu

    2012-07-29

    In the present work, the SnO(2)/graphene nanocomposite composed of 4-5 nm SnO(2) nanoparticles was synthesized using a simple wet chemical method for ppb-level detection of benzene. The formation mechanism of the nanocomposite was investigated systematically by means of simultaneous thermogravimetry analysis, X-ray diffraction, and X-ray photoelectron spectroscopy cooperated with transmission electron microscopy observations. The SnO(2)/graphene nanocomposite showed a very attractive improved sensitivity to toxic volatile organic compounds, especially to benzene, compared to a traditional SnO(2). The responses of the nanocomposite to benzene were a little higher than those to ethanol and the detection limit reached 5 ppb to benzene which is, to our best knowledge, far lower than those reported previously. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. Self-assembled SnO2 micro- and nanosphere-based gas sensor thick films from an alkoxide-derived high purity aqueous colloid precursor

    Science.gov (United States)

    Kelp, G.; Tätte, T.; Pikker, S.; Mändar, H.; Rozhin, A. G.; Rauwel, P.; Vanetsev, A. S.; Gerst, A.; Merisalu, M.; Mäeorg, U.; Natali, M.; Persson, I.; Kessler, V. G.

    2016-03-01

    Tin oxide is considered to be one of the most promising semiconductor oxide materials for use as a gas sensor. However, a simple route for the controllable build-up of nanostructured, sufficiently pure and hierarchical SnO2 structures for gas sensor applications is still a challenge. In the current work, an aqueous SnO2 nanoparticulate precursor sol, which is free of organic contaminants and sorbed ions and is fully stable over time, was prepared in a highly reproducible manner from an alkoxide Sn(OR)4 just by mixing it with a large excess of pure neutral water. The precursor is formed as a separate liquid phase. The structure and purity of the precursor is revealed using XRD, SAXS, EXAFS, HRTEM imaging, FTIR, and XRF analysis. An unconventional approach for the estimation of the particle size based on the quantification of the Sn-Sn contacts in the structure was developed using EXAFS spectroscopy and verified using HRTEM. To construct sensors with a hierarchical 3D structure, we employed an unusual emulsification technique not involving any additives or surfactants, using simply the extraction of the liquid phase, water, with the help of dry butanol under ambient conditions. The originally generated crystalline but yet highly reactive nanoparticles form relatively uniform spheres through self-assembly and solidify instantly. The spheres floating in butanol were left to deposit on the surface of quartz plates bearing sputtered gold electrodes, producing ready-for-use gas sensors in the form of ca. 50 μm thick sphere-based-films. The films were dried for 24 h and calcined at 300 °C in air before use. The gas sensitivity of the structures was tested in the temperature range of 150-400 °C. The materials showed a very quickly emerging and reversible (20-30 times) increase in electrical conductivity as a response to exposure to air containing 100 ppm of H2 or CO and short (10 s) recovery times when the gas flow was stopped.Tin oxide is considered to be one of the

  20. The Application of Metal Oxide Nanomaterials for Chemical Sensor Development

    Science.gov (United States)

    Xu, Jennifer C.; Hunter, Gary W.; Evans, Laura J.; VanderWal, Randy L.; Berger, Gordon M.

    2007-01-01

    NASA Glenn Research Center (GRC) has been developing miniature chemical sensors for a variety of applications including fire detection, emissions monitoring, fuel leak detection, and environmental monitoring. Smart Lick and Stick sensor technology which integrates a sensor array, electronics, telemetry, and power into one microsystem are being developed. These microsystems require low power consumption for long-term aerospace applications. One approach to decreasing power consumption is the use of nanotechnology. Nanocrystalline tin oxide (SnO2) carbon monoxide (CO) sensors developed previously by this group have been successfully used for fire detection and emissions monitoring. This presentation will briefly review the overall NASA GRC chemical sensor program and discuss our further effort in nanotechnology applications. New carbon dioxide (CO2) sensing material using doped nanocrystalline SnO2 will be discussed. Nanocrystalline SnO2 coated solid electrolyte CO2 sensors and SnO2 nanorod and nanofiber hydrogen (H2) sensors operated at reduced or room temperatures will also be discussed.

  1. Microemulsion mediated synthesis of triangular shape SnO2 nanoparticles: Luminescence application

    International Nuclear Information System (INIS)

    Luwang, Meitram Niraj

    2014-01-01

    The triangular prism shapes of SnO 2 ·xH 2 O nanoparticles are prepared using microemulsion route. The effect of variation of water pool value on the formation of SnO 2 nanoparticles was studied. There is the quantum size effect in absorption study of SnO 2 nanoparticles. With the increase of the water pool value, there is a decrease in the band edge absorption energy suggesting the weak quantum confinement effect (QCE) in SnO 2 nanoparticles. Quenching effect increases with increase of water to surfactant ratio in luminescence. There is no significant effect in lifetime values for SnO 2 nanoparticles in both microemulsion and powder form. SnO 2 nanoparticles show green emission due to oxygen vacancy. SnO 2 nanoparticles when doped with Eu 3+ ions give the enhanced luminescence of Eu 3+ due to the surface mediated energy transfer from SnO 2 to Eu 3+ ion.

  2. Field emission characteristics of SnO2/CNT composite prepared by microwave assisted wet impregnation

    CSIR Research Space (South Africa)

    Kesavan Pillai, Sreejarani

    2012-01-01

    Full Text Available SnO2/CNT composites were prepared by microwave assisted wet impregnation at 60 °C. The process was optimized by varying the microwave power and reaction time. Raman analysis showed the typical features of the rutile phase of as-synthesized SnO2...

  3. An economic CVD technique for pure SnO2 thin films deposition ...

    Indian Academy of Sciences (India)

    An economic CVD technique for pure SnO2 thin films deposition: Temperature effects ..... C are depicted in figure 7. It is observed that the cut-off wave- ... cating that the energy gap of the SnO2 films varies among. 3·54, 3·35 and 1·8 eV.

  4. Annealing of SnO2 thin films by ultra-short laser pulses

    NARCIS (Netherlands)

    Scorticati, D.; Illiberi, A.; Bor, T.; Eijt, S.W.H.; Schut, H.; Römer, G.R.B.E.; Lange, D.F. de; Huis In't Veld, A.J.

    2014-01-01

    Post-deposition annealing by ultra-short laser pulses can modify the optical properties of SnO2 thin films by means of thermal processing. Industrial grade SnO2 films exhibited improved optical properties after picosecond laser irradiation, at the expense of a slightly increased sheet resistance

  5. Detection of DNA hybridization based on SnO2 nanomaterial enhanced fluorescence

    International Nuclear Information System (INIS)

    Gu Cuiping; Huang Jiarui; Ni Ning; Li Minqiang; Liu Jinhuai

    2008-01-01

    In this paper, enhanced fluorescence emissions were firstly investigated based on SnO 2 nanomaterial, and its application in the detection of DNA hybridization was also demonstrated. The microarray of SnO 2 nanomaterial was fabricated by the vapour phase transport method catalyzed by patterned Au nanoparticles on a silicon substrate. A probe DNA was immobilized on the substrate with patterned SnO 2 nanomaterial, respectively, by covalent and non-covalent linking schemes. When a fluorophore labelled target DNA was hybridized with a probe DNA on the substrate, fluorescence emissions were only observed on the surface of SnO 2 nanomaterial, which indicated the property of enhancing fluorescence signals from the SnO 2 nanomaterial. By comparing the different fluorescence images from covalent and non-covalent linking schemes, the covalent method was confirmed to be more effective for immobilizing a probe DNA. With the combined use of SnO 2 nanomaterial and the covalent linking scheme, the target DNA could be detected at a very low concentration of 10 fM. And the stability of SnO 2 nanomaterial under the experimental conditions was also compared with silicon nanowires. The findings strongly suggested that SnO 2 nanomaterial could be extensively applied in detections of biological samples with enhancing fluorescence property and high stability

  6. A novel method for massive synthesis of SnO2 nanowires

    Indian Academy of Sciences (India)

    Compositions of three reaction systems for synthesizing SnO2 nanowires by thermite reaction. Constituents (g) ... ing voltage and at a magnification of 3000. .... nanowires to obtain the distribution shown in figure 7. SnO2 ... The Sn drop sprayed ...

  7. Doping of SnO2 with H atoms: An alternative way to attain n-type conductivity

    Directory of Open Access Journals (Sweden)

    Luis Villamagua

    2016-11-01

    Full Text Available We propose an explanation for the origin of n-type electrical conductivity in SnO2 based on the results obtained from the DFT+U simulations. Two competitive intrinsic point defects, namely oxygen vacancy and hydrogen impurity, have been considered at different positions within the crystalline lattice in order to find out the equilibrium configurations and to analyze corresponding density of states (DOS patterns along with the electron localization function (ELF. It has been demonstrated that hydrogen could be solely responsible for the n-type conductivity whereas the oxygen vacancy appears to have not a notable influence upon it. The computational analysis is backed up by some experimental data for undoped tin dioxide.

  8. Characterization of tin oxide nanoparticles synthesized via oxidation from metal; Caracterizacao de nanoparticulas de oxido de estanho sintetizado via oxidacao do metal

    Energy Technology Data Exchange (ETDEWEB)

    Abruzzi, R.C.; Dedavid, B.A.; Pires, M.J.R.; Streicher, M., E-mail: afael.abruzzi@acad.pucrs.br [Pontificia Universidade Catolica do Rio Grande do Sul (PUC-RS), Porto Alegre, RS (Brazil). Pos-Graduacao em Engenharia e Tecnologia de Materiais

    2014-07-01

    The tin oxide (SnO{sub 2}) is a promising material with great potential for applications such as gas sensors and catalysts. This oxide nanostructures show higher activation efficiency due to its larger effective surface. This paper presents the synthesis and characterization of the tin oxide in different conditions, via oxidation of pure tin with nitric acid. Results obtained from the characterization of SnO{sub 2} powder by X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), Energy Dispersive Spectroscopy (EDX), Particle size by Dynamic Light Scattering (DLS) and Infrared Spectroscopy (FTIR) indicated that the conditions were suitable for the synthesis to obtain manometric tin oxide granules with crystalline structure of rutile. (author)

  9. Tin Oxide Nanoparticles: Synthesis, Characterization and Study their Particle Size at Different Current Density

    Directory of Open Access Journals (Sweden)

    Karzan A. Omar

    2013-11-01

    Full Text Available Tin oxide nanoparticles are prepared by electrochemical reduction method using tetrapropylammonium bromide (TPAB and tetrabutylammonium bromide (TBAB as structure directing agent in an organic medium viz. tetrahydrofuran (THF and acetonitrile (ACN in 4:1 ratio by optimizing current density and molar concentration of the ligand. The reduction process takes place under an inert atmosphere of nitrogen over a period of 2 h. Such nanoparticles are prepared by using a simple electrolysis cell in which the sacrificial anode as a commercially available in tin metal sheet and platinum (inert sheet act as a cathode. The parameters such as current density, solvent polarity, distance between electrodes and concentration of stabilizers are used to control the size of nanoparticles. The synthesized tin oxide nanoparticles are characterized by using UV–Visible, FT-IR and SEM–EDS analysis techniques. UV-Visible spectroscopy has revealed the optical band gap to be 4.13, 4.16 and 4.24 ev for (8, 10 and 12 mA/cm2 and the effect of current density on theirs particle size, respectively.

  10. The Research of Micro-structure and Gas Sensitivity of SnO2

    Directory of Open Access Journals (Sweden)

    Mingxin Song

    2014-07-01

    Full Text Available This paper adopts Sol-gel method and solid state reaction to make SnO2 matrix material and Sb2O3 is used as zuji to make SnO2 gas sensor under different sintering temperature. XRD analysis, SEM analysis and response time restoration test of working voltage sensitivity are choose to research SnO2 gas sensor constituents and influence factor on sensing properties by processing. Experiment results show that when the SnO2 make by sol-get method and Sb2O3 take up 2 %, Polyvinyl alcohol as an organic binder, platinum as catalyst, SnO2 gas sensor can get optimal integral sensing properties.

  11. Beneficial effects of rhodium and tin oxide on carbon supported platinum catalysts for ethanol electrooxidation

    Science.gov (United States)

    Soares, Layciane A.; Morais, Claudia; Napporn, Teko W.; Kokoh, K. Boniface; Olivi, Paulo

    2016-05-01

    This work investigates ethanol electrooxidation on Pt/C, PtxRhy/C, Pt-SnO2/C, and PtxRhy-SnO2/C catalysts synthesized by the Pechini and microwave-assisted polyol methods. The catalysts are characterized by energy dispersive X-ray analysis (EDX), transmission electron microscopy (TEM), and X-ray diffraction (XRD) techniques. The electrochemical properties of these electrode materials are examined by cyclic voltammetry and chronoamperometry experiments in acid medium. The products obtained during ethanol electrolysis are identified by high performance liquid chromatography (HPLC). The adsorbed intermediates are evaluated by an in situ reflectance Infrared Spectroscopy technique combined with cyclic voltammetry. Catalysts performance in a direct ethanol fuel cell (DEFC) is also assessed. The electrical performance of the electrocatalysts in a single DEFC at 80 °C decreases in the following order Pt70Rh30SnO2 > Pt80Rh20SnO2 > Pt60Rh40SnO2 ∼ PtSnO2 > PtxRhy ∼ Pt, showing that the presence of SnO2 enhances the ability of Pt to catalyze ethanol electrooxidation.

  12. Effect of Temperature on Nucleation of Nanocrystalline Indium Tin Oxide Synthesized by Electron-Beam Evaporation

    Science.gov (United States)

    Shen, Yan; Zhao, Yujun; Shen, Jianxing; Xu, Xiangang

    2017-07-01

    Indium tin oxide (ITO) has been widely applied as a transparent conductive layer and optical window in light-emitting diodes, solar cells, and touch screens. In this paper, crystalline nano-sized ITO dendrites are obtained using an electron-beam evaporation technique. The surface morphology of the obtained ITO was studied for substrate temperatures of 25°C, 130°C, 180°C, and 300°C. Nano-sized crystalline dendrites were synthesized only at a substrate temperature of 300°C. The dendrites had a cubic structure, confirmed by the results of x-ray diffraction and transmission electron microscopy. The growth mechanism of the nano-crystalline dendrites could be explained by a vapor-liquid-solid (VLS) growth model. The catalysts of the VLS process were indium and tin droplets, confirmed by varying the substrate temperature, which further influenced the nucleation of the ITO dendrites.

  13. A sol-gel method to synthesize indium tin oxide nanoparticles

    Institute of Scientific and Technical Information of China (English)

    Xiuhua Li; Xiujuan xu; Xin Yin; Chunzhong Li; Jianrong Zhang

    2011-01-01

    Transparent conductive indium tin oxide (ITO) nanoparticles were synthesized by a novel sol-gel method.Granulated indium and tin were dissolved in HNO3 and partially complexed with citric acid.A sol-gel process was induced when tertiary butyl alcohol was added dropwise to the above solution.ITO nanoparticles with an average crystallite size of 18.5 nm and surface area of 32.6 m2/g were obtained after the gel was heat-treated at 700 C.The ITO nanoparticles showed good sinterability,the starting sintering temperature decreased sharply to 900 C,and the 1400 C sintered pellet had a density of 98.1 % of theoretical density (TD).

  14. Novel antimony doped tin oxide/carbon aerogel as efficient electrocatalytic filtration membrane

    Directory of Open Access Journals (Sweden)

    Zhimeng Liu

    2016-05-01

    Full Text Available A facile method was developed to prepare antimony doped tin oxide (Sb-SnO2/carbon aerogel (CA for use as an electrocatalytic filtration membrane. The preparation process included synthesis of a precursor sol, impregnation, and thermal decomposition. The Sb-SnO2, which was tetragonal in phase with an average crystallite size of 10.8 nm, was uniformly distributed on the CA surface and firmly attached via carbon-oxygen-tin chemical bonds. Preliminary filtration tests indicated that the Sb-SnO2/CA membrane had a high rate of total organic carbon removal for aqueous tetracycline owing to its high current efficiency and electrode stability.

  15. Characterization of core/shell structures based on CdTe and GaAs nanocrystalline layers deposited on SnO2 microwires

    Science.gov (United States)

    Ghimpu, L.; Ursaki, V. V.; Pantazi, A.; Mesterca, R.; Brâncoveanu, O.; Shree, Sindu; Adelung, R.; Tiginyanu, I. M.; Enachescu, M.

    2018-04-01

    We report the fabrication and characterization of SnO2/CdTe and SnO2/GaAs core/shell microstructures. CdTe or GaAs shell layers were deposited by radio-frequency (RF) magnetron sputtering on core SnO2 microwires synthesized by a flame-based thermal oxidation method. The produced structures were characterized by scanning electron microscopy (SEM), high-resolution scanning transmission electron microscope (HR-STEM), X-ray diffraction (XRD), Raman scattering and FTIR spectroscopy. It was found that the SnO2 core is of the rutile type, while the shells are composed of CdTe or GaAs nanocrystallites of zincblende structure with the dimensions of crystallites in the range of 10-20 nm. The Raman scattering investigations demonstrated that the quality of the porous nanostructured shell is improved by annealing at temperatures of 420-450 °C. The prospects of implementing these microstructures in intrinsic type fiber optic sensors are discussed.

  16. Assembling tin dioxide quantum dots to graphene nanosheets by a facile ultrasonic route.

    Science.gov (United States)

    Chen, Chen; Wang, Lijun; Liu, Yanyu; Chen, Zhiwen; Pan, Dengyu; Li, Zhen; Jiao, Zheng; Hu, Pengfei; Shek, Chan-Hung; Wu, C M Lawrence; Lai, Joseph K L; Wu, Minghong

    2013-03-26

    Nanocomposites have significant potential in the development of advanced materials for numerous applications. Tin dioxide (SnO2) is a functional material with wide-ranging prospects because of its high electronic mobility and wide band gap. Graphene as the basic plane of graphite is a single atomic layer two-dimensional sp(2) hybridized carbon material. Both have excellent physical and chemical properties. Here, SnO2 quantum dots/graphene composites have been successfully fabricated by a facile ultrasonic method. The experimental investigations indicated that the graphene was exfoliated and decorated with SnO2 quantum dots, which was dispersed uniformly on both sides of the graphene. The size distribution of SnO2 quantum dots was estimated to be ranging from 4 to 6 nm and their average size was calculated to be about 4.8 ± 0.2 nm. This facile ultrasonic route demonstrated that the loading of SnO2 quantum dots was an effective way to prevent graphene nanosheets from being restacked during the reduction. During the calcination process, the graphene nanosheets distributed between SnO2 nanoparticles have also prevented the agglomeration of SnO2 nanoparticles, which were beneficial to the formation of SnO2 quantum dots.

  17. Electrochemical Formation of Multilayer SnO2-Sb x O y Coating in Complex Electrolyte.

    Science.gov (United States)

    Maizelis, Antonina; Bairachniy, Boris

    2017-12-01

    The multilayer antimony-doped tin dioxide coating was obtained by cathodic deposition of multilayer metal-hydroxide coating with near 100-nm thickness layers on the alloy underlayer accompanied by the anodic oxidation of this coating. The potential regions of deposition of tin, antimony, tin-antimony alloy, and mixture of this metals and their hydroxides in the pyrophosphate-tartrate electrolyte were revealed by the cyclic voltammetric method. The possibility of oxidation of cathodic deposit consisting of tin and Sn(II) hydroxide compounds to the hydrated tin dioxide in the same electrolyte was demonstrated.The operations of alloy underlayer deposition and oxidation of multilayer metal-hydroxide coating were proposed to carry out in the diluted pyrophosphate-tartrate electrolyte, similar to the main electrolyte.The accelerated tests showed higher service life of the titanium electrode with multilayer antimony-doped tin dioxide coating compared to both electrode with single-layer electrodeposited coating and the electrode with the coating obtained using prolonged heat treatment step.

  18. Enhancement of the electrical characteristics of thin-film transistors with indium-zinc-tin oxide/Ag/indium-zinc-tin oxide multilayer electrodes

    Science.gov (United States)

    Oh, Dohyun; Yun, Dong Yeol; Cho, Woon-Jo; Kim, Tae Whan

    2014-08-01

    Transparent indium-zinc-tin oxide (IZTO)-based thin-film transistors (TFTs) with IZTO/Ag/IZTO multilayer electrodes were fabricated on glass substrates using a tilted dual-target radio-frequency magnetron sputtering system. The IZTO TFTs with IZTO/Ag/IZTO multilayer electrodes exhibited a high optical transmittance in a visible region. The threshold voltage, the mobility, and the on/off-current ratio of the TFTs with IZTO/Ag/IZTO multilayer electrodes were enhanced in comparison with those of the TFTs with ITO electrodes. The source/drain contact resistance of the IZTO TFTs with IZTO/Ag/IZTO multilayer electrodes was smaller than that of the IZTO TFTs with ITO electrodes, resulting in enhancement of their electrical characteristics.

  19. Screen-printed Tin-doped indium oxide (ITO) films for NH3 gas sensing

    International Nuclear Information System (INIS)

    Mbarek, Hedia; Saadoun, Moncef; Bessais, Brahim

    2006-01-01

    Gas sensors using metal oxides have several advantageous features such as simplicity in device structure and low cost fabrication. In this work, Tin-doped indium oxide (ITO) films were prepared by the screen printing technique onto glass substrates. The granular and porous structure of screen-printed ITO are suitable for its use in gas sensing devices. The resistance of the ITO films was found to be strongly dependent on working temperatures and the nature and concentration of the ambient gases. We show that screen-printed ITO films have good sensing properties toward NH 3 vapours. The observed behaviors are explained basing on the oxidizing or the reducer nature of the gaseous species that react on the surface of the heated semi-conducting oxide

  20. Tin dioxide sol-gel derived films doped with platinum and antimony deposited on porous silicon

    NARCIS (Netherlands)

    Savaniu, C.; Arnautu, A.; Cobianu, C.; Craciun, G.; Flueraru, C.; Zaharescu, M.; Parlog, C.; Paszti, F.; van den Berg, Albert

    1999-01-01

    SnO2 sol-gel derived thin films doped simultaneously with Pt and Sb are obtained and reported for the first time. The Sn sources were tin(IV) ethoxide or tin(II) ethylhexanoate, while hexachloroplatinic acid (H2PtCl6) and antimony chloride (SbCl3) were used as platinum and antimony sources,

  1. Silicon surface passivation by PEDOT: PSS functionalized by SnO2 and TiO2 nanoparticles.

    Science.gov (United States)

    García-Tecedor, M; Karazhanov, S Zh; Vásquez, G C; Haug, H; Maestre, D; Cremades, A; Taeño, M; Ramírez-Castellanos, J; González-Calbet, J M; Piqueras, J; You, C C; Marstein, E S

    2018-01-19

    In this paper, we present a study of silicon surface passivation based on the use of spin-coated hybrid composite layers. We investigate both undoped poly(3,4-ethylenedioxythiophene)/poly-(styrenesulfonate) (PEDOT:PSS), as well as PEDOT:PSS functionalized with semiconducting oxide nanomaterials (TiO 2 and SnO 2 ). The hybrid compound was deposited at room temperature by spin coating-a potentially lower cost, lower processing time and higher throughput alternative compared with the commonly used vacuum-based techniques. Photoluminescence imaging was used to characterize the electronic properties of the Si/PEDOT:PSS interface. Good surface passivation was achieved by PEDOT:PSS functionalized by semiconducting oxides. We show that control of the concentration of semiconducting oxide nanoparticles in the polymer is crucial in determining the passivation performance. A charge carrier lifetime of about 275 μs has been achieved when using SnO 2 nanoparticles at a concentration of 0.5 wt.% as a filler in the composite film. X-ray diffraction (XRD), scanning electron microscopy, high resolution transmission electron microscopy (HRTEM), energy dispersive x-ray in an SEM, and μ-Raman spectroscopy have been used for the morphological, chemical and structural characterization. Finally, a simple model of a photovoltaic device based on PEDOT:PSS functionalized with semiconducting oxide nanoparticles has been fabricated and electrically characterized.

  2. Synthesis and lithium storage properties of Zn, Co and Mg doped SnO2 Nano materials

    CSIR Research Space (South Africa)

    Palaniyandy, Nithyadharseni

    2017-09-01

    Full Text Available In this paper, we show that magnesium and cobalt doped SnO2 (Mg-SnO2 and Co-SnO2) nanostructures have profound influence on the discharge capacity and coulombic efficiency of lithium ion batteries (LIBs) employing pure SnO2 and zinc doped SnO2 (Zn-Sn...

  3. Sol–gel synthesis of nanostructured indium tin oxide with controlled morphology and porosity

    Energy Technology Data Exchange (ETDEWEB)

    Kőrösi, László, E-mail: ltkorosi@gmail.com [Department of Biotechnology, Nanophage Therapy Center, Enviroinvest Corporation, Kertváros u. 2, H-7632 Pécs (Hungary); Scarpellini, Alice [Department of Nanochemistry, Istituto Italiano di Tecnologia, via Morego 30, 16163 Genova (Italy); Petrik, Péter [Institute for Technical Physics and Materials Science, Konkoly-Thege út 29-33, H-1121 Budapest (Hungary); Papp, Szilvia [Department of Biotechnology, Nanophage Therapy Center, Enviroinvest Corporation, Kertváros u. 2, H-7632 Pécs (Hungary); Dékány, Imre [MTA-SZTE Supramolecular and Nanostructured Materials Research Group, University of Szeged, Dóm tér 8, H-6720 Szeged (Hungary)

    2014-11-30

    Graphical abstract: - Highlights: • Nanocrystalline ITO thin films and powders were prepared by a sol–gel method. • The nature of the compounds used for hydrolysis plays a key role in the morphology. • Hydrolysis of In{sup 3+}/Sn{sup 4+} with EA led to a rod-like morphology. • Monodisperse spherical ITO nanoparticles were obtained on the use of AC. • ITO{sub E}A was highly porous, while ITO{sub A}C contained densely packed nanocrystals. - Abstract: Nanostructured indium tin oxide (ITO) powders and thin films differing in morphology and porosity were prepared by a sol–gel method. In{sup 3+} and Sn{sup 4+} were hydrolyzed in aqueous medium through the use of ethanolamine (EA) or sodium acetate (AC). X-ray diffraction measurements demonstrated that both EA and AC furnished indium tin hydroxide, which became nanocrystalline after aging for one day. The indium tin hydroxide samples calcined at 550 °C afforded ITO with a cubic crystal structure, but the morphology differed significantly, depending on the agent used for hydrolysis. Electron microscopy revealed the formation of round monodisperse nanoparticles when AC was used, whereas the application of EA led to rod-like ITO nanoparticles. Both types of nanoparticles were suitable for the preparation of transparent and conductive ITO thin films. The influence of the morphology and porosity on the optical properties is discussed.

  4. Structural, optical and electrical properties of tin oxide thin films for application as a wide band gap semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Riti; Ahmad, Shabir; Aziz, Anver; Siddiqui, Azher Majid, E-mail: amsiddiqui@jmi.ac.in [Department of Physics, Jamia Millia Islamia, New Delhi-110025 (India)

    2015-08-28

    Tin oxide (SnO) thin films were synthesized using thermal evaporation technique. Ultra pure metallic tin was deposited on glass substrates using thermal evaporator under high vacuum. The thickness of the tin deposited films was kept at 100nm. Subsequently, the as-deposited tin films were annealed under oxygen environment for a period of 3hrs to obtain tin oxide films. To analyse the suitability of the synthesized tin oxide films as a wide band gap semiconductor, various properties were studied. Structural parameters were studied using XRD and SEM-EDX. The optical properties were studied using UV-Vis Spectrophotometry and the electrical parameters were calculated using the Hall-setup. XRD and SEM confirmed the formation of SnO phase. Uniform texture of the film can be seen through the SEM images. Presence of traces of unoxidised Sn has also been confirmed through the XRD spectra. The band gap calculated was around 3.6eV and the optical transparency around 50%. The higher value of band gap and lower value of optical transparency can be attributed to the presence of unoxidised Sn. The values of resistivity and mobility as measured by the Hall setup were 78Ωcm and 2.92cm{sup 2}/Vs respectively. The reasonable optical and electrical parameters make SnO a suitable candidate for optoelectronic and electronic device applications.

  5. Electrochemistry behavior of endogenous thiols on fluorine doped tin oxide electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Rojas, Luciana; Molero, Leonard; Tapia, Ricardo A.; Rio, Rodrigo del; Valle, M. Angelica del; Antilen, Monica [Departamento de Quimica Inorganica, Facultad de Quimica, Pontificia Universidad Catolica de Chile, Av Vicuna Mackenna 4860, Casilla 306, Correo 22, Macul, Santiago (Chile); Armijo, Francisco, E-mail: jarmijom@uc.cl [Departamento de Quimica Inorganica, Facultad de Quimica, Pontificia Universidad Catolica de Chile, Av Vicuna Mackenna 4860, Casilla 306, Correo 22, Macul, Santiago (Chile)

    2011-10-01

    Highlights: > The first time that fluorine doped tin oxide electrodes are used for the electrooxidation of endogenous thiols. > Low potentials of electrooxidation were obtained for the different thiols. > The electrochemical behavior of thiols depends on the pH and the ionic electroactive species, the electrooxidation proceeds for a process of adsorption of electroactive species on FTO and high values the heterogeneous electron tranfer rate constant of the reaction were obtained. - Abstract: In this work the electrochemical behavior of different thiols on fluorine doped tin oxide (FTO) electrodes is reported. To this end, the mechanism of electrochemical oxidation of glutathione (GSH), cysteine (Cys), homocysteine (HCys) and acetyl-cysteine (ACys) at different pH was investigated. FTO showed electroactivity for the oxidation of the first three thiols at pH between 2.0 and 4.0, but under these conditions no acetyl-cysteine oxidation was observed on FTO. Voltammetric studies of the electro-oxidation of GSH, Cys and HCys showed peaks at about 0.35, 0.29, and 0.28 V at optimum pH 2.4, 2.8 and 3.4, respectively. In addition, this study demonstrated that GSH, Cys and HCys oxidation occurs when the zwitterion is the electro-active species that interact by adsorption on FTO electrodes. The overall reaction involves 4e{sup -}/4H{sup +} and 2e{sup -}/2H{sup +}, respectively, for HCys and for GSH and Cys and high heterogeneous electron transfer rate constants. Besides, the use of FTO for the determination of different thiols was evaluated. Experimental square wave voltammetry shows a linear current vs. concentrations response between 0.1 and 1.0 mM was found for HCys and GSH, indicating that these FTO electrodes are promising candidates for the efficient electrochemical determination of these endogenous thiols.

  6. SnO2/CNT nanocomposite supercapacitors fabricated using scanning atmospheric-pressure plasma jets

    Science.gov (United States)

    Xu, Chang-Han; Chiu, Yi-Fan; Yeh, Po-Wei; Chen, Jian-Zhang

    2016-08-01

    SnO2/CNT electrodes for supercapacitors are fabricated by first screen-printing pastes containing SnO2 nanoparticles and CNTs on carbon cloth, following which nitrogen atmospheric pressure plasma jet (APPJ) sintering is performed at various APPJ scan rates. The APPJ scan rates change the time intervals for which the reactive plasma species and the heat of the nitrogen APPJs influence the designated sintering spot on the carbon cloth, resulting in APPJ-sintered SnO2/CNT nanocomposites with different properties. The water contact angle decreases with the APPJ scan rate. The improved wettability can facilitate the penetration of the electrolyte into the nanopores of the SnO2/CNT nanocomposites, thereby improving the charge storage and specific capacitance of the supercapacitors. Among the three tested APPJ scan rates, 1.5, 3, and 6 mm s-1, the SnO2/CNT supercapacitor sintered by APPJ under the lowest APPJ scan rate of 1.5 mm s-1 shows the best specific capacitance of ˜90 F g-1 as evaluated by cyclic voltammetry under a potential scan rate of 2 mV s-1. A high APPJ scan rate may result in low degree of materials activation and sintering, leading to poorer performance of SnO2/CNT supercapacitors. The results suggest the feasibility of an APPJ roll-to-roll process for the fabrication of SnO2/CNT nanocomposite supercapacitors.

  7. Physical and photoelectrochemical properties of Sb-doped SnO2 thin films deposited by chemical vapor deposition: application to chromate reduction under solar light

    Science.gov (United States)

    Outemzabet, R.; Doulache, M.; Trari, M.

    2015-05-01

    Sb-doped SnO2 thin films (Sb-SnO2) are prepared by chemical vapor deposition. The X-ray diffraction indicates a rutile phase, and the SEM analysis shows pyramidal grains whose size extends up to 200 nm. The variation of the film thickness shows that the elaboration technique needs to be optimized to give reproducible layers. The films are transparent over the visible region. The dispersion of the optical indices is evaluated by fitting the diffuse reflectance data with the Drude-Lorentz model. The refractive index ( n) and absorption coefficient ( k) depend on both the conditions of preparation and of the doping concentration and vary between 1.4 and 2.0 and 0.2 and 0.01, respectively. Tin oxide is nominally non-stoichiometric, and the conduction is dominated by thermally electrons jump with an electron mobility of 12 cm2 V-1 s-1 for Sb-SnO2 (1 %). The ( C 2- V) characteristic in aqueous electrolyte exhibits a linear behavior from which an electrons density of 4.15 × 1018 cm-3 and a flat-band potential of -0.83 V SCE are determined. The electrochemical impedance spectroscopy shows a semicircle attributed to a capacitive behavior with a low density of surface states. The center lies below the real axis with a depletion angle (12°), due to a constant phase element, i.e., a deviation from a pure capacitive behavior, presumably attributed to the roughness and porosity of the film. The straight line at low frequencies is attributed to the Warburg diffusion. The energy diagram reveals the photocatalytic feasibility of Sb-SnO2. As application, 90 % of the chromate concentration (20 mg L-1, pH ~3) disappears after 6 h of exposure to solar light.

  8. ZnO doped SnO2 nanoparticles heterojunction photo-catalyst for environmental remediation

    International Nuclear Information System (INIS)

    Lamba, Randeep; Umar, Ahmad; Mehta, S.K.; Kansal, Sushil Kumar

    2015-01-01

    ZnO doped SnO 2 nanoparticles were synthesized by facile and simple hydrothermal technique and used as an effective photocatalyst for the photocatalytic degradation of harmful and toxic organic dye. The prepared nanoparticles were characterized in detail using different techniques for morphological, structural and optical properties. The characterization results revealed that the synthesized nanoparticles possess both crystal phases of tetragonal rutile phase of pure SnO 2 and wurtzite hexagonal phase of ZnO. In addition, the nanoparticles were synthesized in very high quantity with good crystallinity. The photocatalytic activity of prepared nanoparticles was evaluated by the photocatalytic degradation of methylene blue (MB) dye. Detailed photocatalytic experiments based on the effects of irradiation time, catalyst dose and pH were performed and presented in this paper. The detailed photocatalytic experiments revealed that the synthesized ZnO doped SnO 2 nanoparticles heterojunction photocatalyst exhibit best photocatalytic performance when the catalyst dose was 0.25 g/L and pH = 10. ZnO doped SnO 2 nanoparticles heterojunction photocatalyst was also compared with commercially available TiO 2 (PC-50), TiO 2 (PC-500) and SnO 2 and interestingly ZnO doped SnO 2 nanoparticles exhibited superior photocatalytic performance. The presented work demonstrates that the prepared ZnO doped SnO 2 nanoparticles are promising material for the photocatalytic degradation of organic dyes and toxic chemicals. - Highlights: • Synthesis of well-crystalline ZnO-doped SnO 2 nanoparticles. • Excellent morphological, crystalline and photoluminescent properties. • Efficient environmental remediation using ZnO-doped SnO 2 nanoparticles.

  9. In situ carbon encapsulation of vertical MoS2 arrays with SnO2 for durable high rate lithium storage: dominant pseudocapacitive behavior.

    Science.gov (United States)

    Li, Mengjiao; Deng, Qinglin; Wang, Junyong; Jiang, Kai; Hu, Zhigao; Chu, Junhao

    2018-01-03

    Improving the conductivity and charge transfer kinetics is favourable for innovation of sustainable energy devices such as metal oxide/sulfide-based electrodes. Herein, with an intercalation pseudocapacitance effect, an in situ polymerization-carbonization process for novel carbon-sealed vertical MoS 2 -SnO 2 anchored on graphene aerogel (C@MoS 2 -SnO 2 @Gr) has enabled excellent rate performance and durability of the anode of lithium ion batteries to be achieved. The integrated carbon layer and graphene matrix provide a bicontinuous conductive network for efficient electron/ion diffusion pathways. The charge transfer kinetics could be enhanced by the synergistic effects between vertical MoS 2 nanosheets and well-dispersed SnO 2 particles. Based on the crystal surface matching, the ameliorated electric contact between MoS 2 and SnO 2 can promote the extraction of Li + from Li 2 O and restrain the serious aggregation of Li x Sn. As a result, the improved reversibility leads to a higher initial coulombic efficiency (ICE) of 80% (0.1 A g -1 current density) compared to that of other materials. In particular, with the dominating surface capacitive process, the C@MoS 2 -SnO 2 @Gr electrode delivers a stable capacity of 680 mA h g -1 at 2.5 A g -1 for 2000 cycles. Quantitative insight into the origin of the boosted kinetics demonstrated the high pseudocapacitance contribution (above 90%) which leads to the durable high rate Li ion storage.

  10. Graphene/Fe2O3/SnO2 ternary nanocomposites as a high-performance anode for lithium ion batteries.

    Science.gov (United States)

    Xia, Guofeng; Li, Ning; Li, Deyu; Liu, Ruiqing; Wang, Chen; Li, Qing; Lü, Xujie; Spendelow, Jacob S; Zhang, Junliang; Wu, Gang

    2013-09-11

    We report an rGO/Fe2O3/SnO2 ternary nanocomposite synthesized via homogeneous precipitation of Fe2O3 nanoparticles onto graphene oxide (GO) followed by reduction of GO with SnCl2. The reduction mechanism of GO with SnCl2 and the effects of reduction temperature and time were examined. Accompanying the reduction of GO, particles of SnO2 were deposited on the GO surface. In the graphene nanocomposite, Fe2O3 nanoparticles with a size of ∼20 nm were uniformly dispersed surrounded by SnO2 nanoparticles, as demonstrated by transmission electron microscopy analysis. Due to the different lithium insertion/extraction potentials, the major role of SnO2 nanoparticles is to prevent aggregation of Fe2O3 during the cycling. Graphene can serve as a matrix for Li+ and electron transport and is capable of relieving the stress that would otherwise accumulate in the Fe2O3 nanoparticles during Li uptake/release. In turn, the dispersion of nanoparticles on graphene can mitigate the restacking of graphene sheets. As a result, the electrochemical performance of rGO/Fe2O3/SnO2 ternary nanocomposite as an anode in Li ion batteries is significantly improved, showing high initial discharge and charge capacities of 1179 and 746 mAhg(-1), respectively. Importantly, nearly 100% discharge-charge efficiency is maintained during the subsequent 100 cycles with a specific capacity above 700 mAhg(-1).

  11. Cyclic etching of tin-doped indium oxide using hydrogen-induced modified layer

    Science.gov (United States)

    Hirata, Akiko; Fukasawa, Masanaga; Nagahata, Kazunori; Li, Hu; Karahashi, Kazuhiro; Hamaguchi, Satoshi; Tatsumi, Tetsuya

    2018-06-01

    The rate of etching of tin-doped indium oxide (ITO) and the effects of a hydrogen-induced modified layer on cyclic, multistep thin-layer etching were investigated. It was found that ITO cyclic etching is possible by precisely controlling the hydrogen-induced modified layer. Highly selective etching of ITO/SiO2 was also investigated, and it was suggested that cyclic etching by selective surface adsorption of Si can precisely control the etch rates of ITO and SiO2, resulting in an almost infinite selectivity for ITO over SiO2 and in improved profile controllability.

  12. Electrical and optical properties of indium tin oxide/epoxy composite film

    International Nuclear Information System (INIS)

    Guo Xia; Guo Chun-Wei; Chen Yu; Su Zhi-Ping

    2014-01-01

    The electrical and optical properties of the indium tin oxide (ITO)/epoxy composite exhibit dramatic variations as functions of the ITO composition and ITO particle size. Sharp increases in the conductivity in the vicinity of a critical volume fraction have been found within the framework of percolation theory. A conductive and insulating transition model is extracted by the ITO particle network in the SEM image, and verified by the resistivity dependence on the temperature. The dependence of the optical transmittance on the particle size was studied. Further decreasing the ITO particle size could further improve the percolation threshold and light transparency of the composite film. (condensed matter: structural, mechanical, and thermal properties)

  13. Magnetoresistance and Microstructure of Magnetite Nanocrystals Dispersed in Indium−Tin Oxide Thin Films

    OpenAIRE

    Okada, Koichi; Kohiki, Shigemi; Mitome, Masanori; Tanaka, Hidekazu; Arai, Masao; Mito, Masaki; Deguchi, Hiroyuki

    2009-01-01

    Epitaxial indium−tin oxide (ITO) thin films were fabricated on a yttria-stabilized zirconia (YSZ) substrate by pulsed-laser deposition using magnetite (Fe3O4) nanoparticle dispersed ITO powders as a target. Magnetoresistance of the film at a field of 1 T was 39% at 45 K, and it stayed at 3% above 225 K. The film demonstrated cooling hysteresis in the temperature dependence of direct-current magnetization. Transmission electron microscopy revealed that phase-separated Fe3O4 nanocrystals with w...

  14. Deposition of indium tin oxide films on acrylic substrates by radiofrequency magnetron sputtering

    International Nuclear Information System (INIS)

    Chiou, B.S.; Hsieh, S.T.; Wu, W.F.

    1994-01-01

    Indium tin oxide (ITO) films were deposited onto acrylic substrates by rf magnetron sputtering. Low substrate temperature (< 80 C) and low rf power (< 28 W) were maintained during sputtering to prevent acrylic substrate deformation. The influence of sputtering parameters, such as rf power, target-to-substrate distance, and chamber pressure, on the film deposition rate, the electrical properties, as well as the optical properties of the deposited films was investigated. Both the refractive index and the extinction coefficient were derived. The high reflection at wavelengths greater than 3 μm made these sputtered ITO films applicable to infrared mirrors

  15. Effect of Target Density on Microstructural, Electrical, and Optical Properties of Indium Tin Oxide Thin Films

    Science.gov (United States)

    Zhu, Guisheng; Zhi, Li; Yang, Huijuan; Xu, Huarui; Yu, Aibing

    2012-09-01

    In this paper, indium tin oxide (ITO) targets with different densities were used to deposit ITO thin films. The thin films were deposited from these targets at room temperature and annealed at 750°C. Microstructural, electrical, and optical properties of the as-prepared films were studied. It was found that the target density had no effect on the properties or deposition rate of radiofrequency (RF)-sputtered ITO thin films, different from the findings for direct current (DC)-sputtered films. Therefore, when using RF sputtering, the target does not require a high density and may be reused.

  16. Enhanced diode characteristics of organic solar cell with silanized fluorine doped tin oxide electrode

    Science.gov (United States)

    Sachdeva, Sheenam; Sharma, Sameeksha; Singh, Devinder; Tripathi, S. K.

    2018-05-01

    To investigate the diode characteristics of organic solar cell based on the planar heterojunction of 4,4'- cyclohexylidenebis[N,N-bis(4-methylphenyl)benzenamine] (TAPC) and fullerene (C70), we report the use of silanized fluorine-doped tin oxide (FTO) anode with N1-(3-trimethoxysilylpropyl)diethyltriamine (DETA) forming monolayer. The use of silanized FTO results in the decrease of saturation current density and diode ideality factor of the device. Such silanized FTO anode is found to enhance the material quality and improve the device properties.

  17. Fundamental electrochemiluminescence characteristics of fluorine-doped tin oxides synthesized by sol-gel combustion.

    Science.gov (United States)

    Moon, B H; Chaoumead, A; Sung, Y M

    2013-10-01

    Fluorine-doped tin oxide (FTO) materials synthesized by sol-gel combustion method were investigated for electrochemical luminescence (ECL) application. Effects of sol-gel combustion conditions on the structures and morphology of the porous FTO (p-FTO) materials were studied. ECL efficiency of p-FTO-based cell was about 251 cd/m2 at 4 V bias, which is higher than the sell using only FTO electrodes (102.8 cd/m2). The highest intensity of the emitting light was obtained at the wavelength of about 610 nm. The porous FTO layer was effective for increasing ECL intensities.

  18. Transparent heaters based on solution-processed indium tin oxide nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Im, Kiju [Department of Electrical Engineering and Institute for Nano Science, Korea University, 5-1, Anam-dong, Sungbuk-gu, Seoul 136-701 (Korea, Republic of); Research Institute of TNB Nanoelec Co. Ltd., Seoul 136-701 (Korea, Republic of); Cho, Kyoungah [Department of Electrical Engineering and Institute for Nano Science, Korea University, 5-1, Anam-dong, Sungbuk-gu, Seoul 136-701 (Korea, Republic of); Kim, Jonghyun [Research Institute of TNB Nanoelec Co. Ltd., Seoul 136-701 (Korea, Republic of); Kim, Sangsig, E-mail: sangsig@korea.ac.k [Department of Electrical Engineering and Institute for Nano Science, Korea University, 5-1, Anam-dong, Sungbuk-gu, Seoul 136-701 (Korea, Republic of)

    2010-05-03

    We demonstrate transparent heaters constructed on glass substrates using solution-processed indium tin oxide (ITO) nanoparticles (NPs) and their heating capability. The heat-generating characteristics of the heaters depended significantly on the sintering temperature at which the ITO NPs deposited on a glass substrate by spin-coating were transformed thermally into a solid film. The steady-state temperature of the ITO NP film sintered at 400 {sup o}C was 163 {sup o}C at a bias voltage of 20 V, and the defrosting capability of the film was confirmed by using dry-ice.

  19. Indium Tin Oxide-Free Polymer Solar Cells: Toward Commercial Reality

    DEFF Research Database (Denmark)

    Angmo, Dechan; Espinosa Martinez, Nieves; Krebs, Frederik C

    2014-01-01

    Polymer solar cell (PSC) is the latest of all photovoltaic technologies which currently lies at the brink of commercialization. The impetus for its rapid progress in the last decade has come from low-cost high throughput production possibility which in turn relies on the use of low-cost materials...... and vacuum-free manufacture. Indium tin oxide (ITO), the commonly used transparent conductor, imposes the majority of the cost of production of PSCs, limits flexibility, and is feared to create bottleneck in the dawning industry due to indium scarcity and the resulting large price fluctuations. As such...

  20. Characterization of lead zirconate titanate (PZT)--indium tin oxide (ITO) thin film interface

    International Nuclear Information System (INIS)

    Sreenivas, K.; Sayer, M.; Laursen, T.; Whitton, J.L.; Pascual, R.; Johnson, D.J.; Amm, D.T.

    1990-01-01

    In this paper the interface between ultrathin sputtered lead zirconate titanate (PZT) films and a conductive electrode (indium tin oxide-ITO) is investigated. Structural and compositional changes at the PZT-ITO interface have been examined by surface analysis and depth profiling techniques of glancing angle x-ray diffraction, Rutherford backscattering (RBS), SIMS, Auger electron spectroscopy (AES), and elastic recoil detection analysis (ERDA). Studies indicate significant interdiffusion of lead into the underlying ITP layer and glass substrate with a large amount of residual stress at the interface. Influence of such compositional deviations at the interface is correlated to an observed thickness dependence in the dielectric properties of PZT films

  1. The Effects of Oxidation Layer, Temperature, and Stress on Tin Whisker Growth: A Short Review

    Science.gov (United States)

    Mahim, Z.; Salleh, M. A. A.; Khor, C. Y.

    2018-03-01

    In order to reduce the Tin (Sn) whisker growth phenomenon in solder alloys, the researcher all the world has studied the factor of this behaviour. However, this phenomenon still hunted the electronic devices and industries. The whiskers growth were able to cause the electrical short, which would lead to the catastrophic such as plane crush, the failure of heart pacemaker, and the lost satellite connection. This article focuses on the three factors that influence the whiskers growth in solder alloys which is stress, oxidation layer and temperature. This findings were allowed the researchers to develop various method on how to reduce the growth of the Sn whiskers.

  2. Gold island films on indium tin oxide for localized surface plasmon sensing

    International Nuclear Information System (INIS)

    Szunerits, Sabine; Praig, Vera G; Manesse, Mael; Boukherroub, Rabah

    2008-01-01

    Mechanically, chemically and optically stable gold island films were prepared on indium tin oxide (ITO) substrates by direct thermal evaporation of thin gold films (2-6 nm) without the need for pre- or post-coating. The effect of mild thermal annealing (150 deg. C, 12 h) or short high temperature annealing (500 deg. C, 1 min) on the morphology of the gold nanostructures was investigated. ITO covered with 2 nm gold nanoislands and annealed at 500 deg. C for 1 min was investigated for its ability to detect the adsorption of biotinylated bovine serum albumin using local surface plasmon resonance (LSPR), and its subsequent molecular recognition of avidin

  3. Low Reflectivity and High Flexibility of Tin-Doped Indium Oxide Nanofiber Transparent Electrodes

    KAUST Repository

    Wu, Hui

    2011-01-12

    Tin-doped indium oxide (ITO) has found widespread use in solar cells, displays, and touch screens as a transparent electrode; however, two major problems with ITO remain: high reflectivity (up to 10%) and insufficient flexibility. Together, these problems severely limit the applications of ITO films for future optoelectronic devices. In this communication, we report the fabrication of ITO nanofiber network transparent electrodes. The nanofiber networks show optical reflectivity as low as 5% and high flexibility; the nanofiber networks can be bent to a radius of 2 mm with negligible changes in the sheet resistance. © 2010 American Chemical Society.

  4. Indium-tin oxide surface treatments: Effects on the performance of liquid crystal devices

    International Nuclear Information System (INIS)

    Abderrahmen, A.; Romdhane, F.F.; Ben Ouada, H.; Gharbi, A.

    2006-01-01

    In this work, we investigate the effect of indium tin oxide (ITO) substrate cleaning on the surface properties. Wettability technique was used to measure the contact angle and the surface energy of the different treated ITO substrates. It is found that treatment with the methanol without dehydration gives the lowest water contact angle (most hydrophilic surface) and the highest surface energy compared to other solvents. This result was confirmed by impedance measurements performed on nematic liquid crystal cells with ITO electrodes. Indeed, we check the decrease of ionic entities in the interface ITO/liquid crystal. The polarity and dielectric parameters of the used solvents explain the obtained results

  5. Indium-tin oxide surface treatments: Effects on the performance of liquid crystal devices

    Energy Technology Data Exchange (ETDEWEB)

    Abderrahmen, A. [Laboratoire de physique et chimie des interfaces, Faculte des sciences, 5000, Monastir (Tunisia)]. E-mail: asma_abderrahmen@yahoo.fr; Romdhane, F.F. [Laboratoire de la matiere molle, Faculte des sciences, Tunis (Tunisia); Ben Ouada, H. [Laboratoire de physique et chimie des interfaces, Faculte des sciences, 5000, Monastir (Tunisia); Gharbi, A. [Laboratoire de la matiere molle, Faculte des sciences, Tunis (Tunisia)

    2006-03-15

    In this work, we investigate the effect of indium tin oxide (ITO) substrate cleaning on the surface properties. Wettability technique was used to measure the contact angle and the surface energy of the different treated ITO substrates. It is found that treatment with the methanol without dehydration gives the lowest water contact angle (most hydrophilic surface) and the highest surface energy compared to other solvents. This result was confirmed by impedance measurements performed on nematic liquid crystal cells with ITO electrodes. Indeed, we check the decrease of ionic entities in the interface ITO/liquid crystal. The polarity and dielectric parameters of the used solvents explain the obtained results.

  6. Studies on the optoelectronic properties of the thermally evaporated tin-doped indium oxide nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Ko-Ying [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan, ROC (China); Lin, Liang-Da [Institute of Materials Science and Nanotechnology, Chinese Culture University, Taipei 111, Taiwan, ROC (China); Chang, Li-Wei [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan, ROC (China); Shih, Han C., E-mail: hcshih@mx.nthu.edu.tw [Department of Materials Science and Engineering, National Tsing Hua University, Hsinchu 300, Taiwan, ROC (China); Institute of Materials Science and Nanotechnology, Chinese Culture University, Taipei 111, Taiwan, ROC (China)

    2013-05-15

    Indium oxide (In{sub 2}O{sub 3}) nanorods, nanotowers and tin-doped (Sn:In = 1:100) indium oxide (ITO) nanorods have been fabricated by thermal evaporation. The morphology, microstructure and chemical composition of these three nanoproducts are characterized by FE-SEM, HRTEM and XPS. To further investigate the optoelectronic properties, the I–V curves and cathodoluminescence (CL) spectra are measured. The electrical resistivity of In{sub 2}O{sub 3} nanorods, nanotowers and ITO nanorods are 1.32 kΩ, 0.65 kΩ and 0.063 kΩ, respectively. CL spectra of these three nanoproducts clearly indicate that tin-doped (Sn:In = 1:100) indium oxide (ITO) nanorods cause a blue shift. No doubt ITO nanorods obtain the highest performance among these three nanoproducts, and this also means that Sn-doped In{sub 2}O{sub 3} nanostructures would be the best way to enhance the optoelectronic properties. Additionally, the growing mechanism and the optoelectronic properties of these three nanostructures are discussed. This study is beneficial to the applications of In{sub 2}O{sub 3} nanorods, nanotowers and ITO nanorods in optoelectronic nanodevices.

  7. Room temperature ferromagnetism of tin oxide nanocrystal based on synthesis methods

    Energy Technology Data Exchange (ETDEWEB)

    Sakthiraj, K.; Hema, M. [Department of Physics, Kamaraj College of Engineering and Technology, Virudhunagar 626001, Tamil Nadu (India); Balachandrakumar, K. [Department of Physics, Raja Doraisingam Government Arts College, Sivagangai 630561, Tamil Nadu (India)

    2016-04-15

    The experimental conditions used in the preparation of nanocrystalline oxide materials play an important role in the room temperature ferromagnetism of the product. In the present work, a comparison was made between sol–gel, microwave assisted sol–gel and hydrothermal methods for preparing tin oxide nanocrystal. X-ray diffraction analysis indicates the formation of tetragonal rutile phase structure for all the samples. The crystallite size was estimated from the HRTEM images and it is around 6–12 nm. Using optical absorbance measurement, the band gap energy value of the samples has been calculated. It reveals the existence of quantum confinement effect in all the prepared samples. Photoluminescence (PL) spectra confirms that the luminescence process originates from the structural defects such as oxygen vacancies present in the samples. Room temperature hysteresis loop was clearly observed in M–H curve of all the samples. But the sol–gel derived sample shows the higher values of saturation magnetization (M{sub s}) and remanence (M{sub r}) than other two samples. This study reveals that the sol–gel method is superior to the other two methods for producing room temperature ferromagnetism in tin oxide nanocrystal.

  8. Synthesis and characterization of single-crystalline zinc tin oxide nanowires

    Science.gov (United States)

    Shi, Jen-Bin; Wu, Po-Feng; Lin, Hsien-Sheng; Lin, Ya-Ting; Lee, Hsuan-Wei; Kao, Chia-Tze; Liao, Wei-Hsiang; Young, San-Lin

    2014-05-01

    Crystalline zinc tin oxide (ZTO; zinc oxide with heavy tin doping of 33 at.%) nanowires were first synthesized using the electrodeposition and heat treatment method based on an anodic aluminum oxide (AAO) membrane, which has an average diameter of about 60 nm. According to the field emission scanning electron microscopy (FE-SEM) results, the synthesized ZTO nanowires are highly ordered and have high wire packing densities. The length of ZTO nanowires is about 4 μm, and the aspect ratio is around 67. ZTO nanowires with a Zn/(Zn + Sn) atomic ratio of 0.67 (approximately 2/3) were observed from an energy dispersive spectrometer (EDS). X-ray diffraction (XRD) and corresponding selected area electron diffraction (SAED) patterns demonstrated that the ZTO nanowire is hexagonal single-crystalline. The study of ultraviolet/visible/near-infrared (UV/Vis/NIR) absorption showed that the ZTO nanowire is a wide-band semiconductor with a band gap energy of 3.7 eV.

  9. Compositional influence on the electrical performance of zinc indium tin oxide transparent thin-film transistors

    International Nuclear Information System (INIS)

    Marsal, A.; Carreras, P.; Puigdollers, J.; Voz, C.; Galindo, S.; Alcubilla, R.; Bertomeu, J.; Antony, A.

    2014-01-01

    In this work, zinc indium tin oxide layers with different compositions are used as the active layer of thin film transistors. This multicomponent transparent conductive oxide is gaining great interest due to its reduced content of the scarce indium element. Experimental data indicate that the incorporation of zinc promotes the creation of oxygen vacancies, which results in a higher free carrier density. In thin-film transistors this effect leads to a higher off current and threshold voltage values. The field-effect mobility is also strongly degraded, probably due to coulomb scattering by ionized defects. A post deposition annealing in air reduces the density of oxygen vacancies and improves the field-effect mobility by orders of magnitude. Finally, the electrical characteristics of the fabricated thin-film transistors have been analyzed to estimate the density of states in the gap of the active layers. These measurements reveal a clear peak located at 0.3 eV from the conduction band edge that could be attributed to oxygen vacancies. - Highlights: • Zinc promotes the creation of oxygen vacancies in zinc indium tin oxide transistors. • Post deposition annealing in air reduces the density of oxygen. • Density of states reveals a clear peak located at 0.3 eV from the conduction band

  10. Sulfated tin oxide (STO – Structural properties and application in catalysis: A review

    Directory of Open Access Journals (Sweden)

    Ravi Varala

    2016-07-01

    Full Text Available Catalysis is an important area of chemistry, with an extensive amount of work going on in this area of sciences, toward synthesis and evaluation of newer catalysts. There are many reports for different conversion reactions such as oxidation, reduction, coupling, alkylation, and acylation for which various catalysts have been used such as mixed metal oxides, metal nanoparticles, metal organic complexes and many others. Among the many catalysts reported, the one catalyst that caught our attention due to its exploitation for a plethora of organic conversions is the sulfated tin oxide (STO, which is due to the low cost, greater stability and high efficiency of the catalyst. In this review, we have attempted to compile data about the structural properties of STO, and its applications as catalysts in various organic synthesis are presented. The literature data up to 2014 were collected and considered for the review.

  11. Gold nanoparticle arrays directly grown on nanostructured indium tin oxide electrodes: Characterization and electroanalytical application

    International Nuclear Information System (INIS)

    Zhang Jingdong; Oyama, Munetaka

    2005-01-01

    This work describes an improved seed-mediated growth approach for the direct attachment and growth of mono-dispersed gold nanoparticles on nanostructured indium tin oxide (ITO) surfaces. It was demonstrated that, when the seeding procedure of our previously reported seed-mediated growth process on an ITO surface was modified, the density of gold nanospheres directly grown on the surface could be highly improved, while the emergence of nanorods was restrained. By field emission scanning electron microscopy (FE-SEM) and cyclic voltammetry, the growth of gold nanoparticles with increasing growth time on the defect sites of nanostructured ITO surface was monitored. Using a [Fe(China) 6 ] 3- /[Fe(China) 6 ] 4- redox probe, the increasingly facile heterogeneous electron transfer kinetics resulting from the deposition and growth of gold nanoparticle arrays was observed. The as-prepared gold nanoparticle arrays exhibited high catalytic activity toward the electrooxidation of nitric oxide, which could provide electroanalytical application for nitric oxide sensing

  12. Effects of process parameters on sheet resistance uniformity of fluorine-doped tin oxide thin films

    Science.gov (United States)

    Hudaya, Chairul; Park, Ji Hun; Lee, Joong Kee

    2012-01-01

    An alternative indium-free material for transparent conducting oxides of fluorine-doped tin oxide [FTO] thin films deposited on polyethylene terephthalate [PET] was prepared by electron cyclotron resonance - metal organic chemical vapor deposition [ECR-MOCVD]. One of the essential issues regarding metal oxide film deposition is the sheet resistance uniformity of the film. Variations in process parameters, in this case, working and bubbler pressures of ECR-MOCVD, can lead to a change in resistance uniformity. Both the optical transmittance and electrical resistance uniformity of FTO film-coated PET were investigated. The result shows that sheet resistance uniformity and the transmittance of the film are affected significantly by the changes in bubbler pressure but are less influenced by the working pressure of the ECR-MOCVD system.

  13. Inkjet printed ambipolar transistors and inverters based on carbon nanotube/zinc tin oxide heterostructures

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Bongjun; Jang, Seonpil; Dodabalapur, Ananth, E-mail: ananth.dodabalapur@engr.utexas.edu [Microelectronics Research Center, The University of Texas at Austin, Austin, Texas 78758 (United States); Department of Electrical and Computer Engineering, The University of Texas at Austin, Austin, Texas 78712 (United States); Geier, Michael L.; Prabhumirashi, Pradyumna L. [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Hersam, Mark C. [Department of Materials Science and Engineering, Northwestern University, Evanston, Illinois 60208 (United States); Department of Chemistry, Northwestern University, Evanston, Illinois 60208 (United States); Department of Medicine, Northwestern University, Evanston, Illinois 60208 (United States)

    2014-02-10

    We report ambipolar field-effect transistors (FETs) consisting of inkjet printed semiconductor bilayer heterostructures utilizing semiconducting single-walled carbon nanotubes (SWCNTs) and amorphous zinc tin oxide (ZTO). The bilayer structure allows for electron transport to occur principally in the amorphous oxide layer and hole transport to occur exclusively in the SWCNT layer. This results in balanced electron and hole mobilities exceeding 2 cm{sup 2} V{sup −1} s{sup −1} at low operating voltages (<5 V) in air. We further show that the SWCNT-ZTO hybrid ambipolar FETs can be integrated into functional inverter circuits that display high peak gain (>10). This work provides a pathway for realizing solution processable, inkjet printable, large area electronic devices, and systems based on SWCNT-amorphous oxide heterostructures.

  14. The Preparation and Property of Graphene /Tin Oxide Transparent Conductive Film

    Directory of Open Access Journals (Sweden)

    SUN Tao

    2017-02-01

    Full Text Available Graphene doped tin oxide composites were prepared with SnCIZ·2HZ 0 and graphene oxide as raw materials with sol-gel method and then spincoated on the quartz glass to manufacture a new transparent conductive film. The composite film was characterized with X-ray diffraction(XRDand scanning electron microscopy(SEM analysis. XRD results show that the graphene oxide was successfully prepared with Hummers method. The graphene layers and particulate SnOZ can be clearly observed in SEM photos. The transmittance and conductivity of the thin films were tested with ultraviolet visible spectrophotometer and Hall effect measurement. The results show that the transmittivity of composite film in visible region is more than 90% and surface square resistance is 41 S2/口.The graphene/ SnOZ film exhibits a higher performance in transparence and conductivity than commercial FTO glass.

  15. Carbon-coated mesoporous SnO2 nanospheres as anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Wang, Fei; Song, Xiaoping; Yao, Gang; Zhao, Mingshu; Liu, Rui; Xu, Minwei; Sun, Zhanbo

    2012-01-01

    In this paper mesoporous SnO 2 nanospheres with an average diameter of about 83 nm, composed of many tiny primary particles (∼10 nm) and holes, are synthesized on a large scale by a simple hydrothermal route. The as-prepared mesoporous SnO 2 nanospheres were uniformly coated with carbon by a further hydrothermal treatment in glucose aqueous solution. As anode materials for lithium-ion batteries, the core–shell SnO 2 /C nanocomposites exhibit a markedly improved cycling performance.

  16. Application of sol-gel process on the elaboration of SnO2 based ceramics

    International Nuclear Information System (INIS)

    Prescatan, R.T.; Silva, D.V. da; Hiratsuka, R.S.; Santilli, C.V.; Pulcinelli, S.H.

    1990-01-01

    The electrical, optical and chemical peculiar properties of SnO 2 confers it-self some potential application. The densification difficulty during sintering of SnO 2 compromises its elaboration by ceramic conventional process. In this work the preparation of SnO 2 ceramics by sol-gel process was investigated. Some parameters envolved on the colloidal stability, sol-gel transition and drying process were analysed. The obtained materials were characterized by rheological, X-ray diffraction, infra-red spectroscopy and pores size distribution measurements. The results show that a considerable densification during sintering at 400 and 600 0 C was obtained. (author) [pt

  17. Acetylene Gas-Sensing Properties of Layer-by-Layer Self-Assembled Ag-Decorated Tin Dioxide/Graphene Nanocomposite Film

    Directory of Open Access Journals (Sweden)

    Chuanxing Jiang

    2017-09-01

    Full Text Available This paper demonstrates an acetylene gas sensor based on an Ag-decorated tin dioxide/reduced graphene oxide (Ag–SnO2/rGO nanocomposite film, prepared by layer-by-layer (LbL self-assembly technology. The as-prepared Ag–SnO2/rGO nanocomposite was characterized by scanning electron microscopy (SEM, transmission electron microscopy (TEM, X-ray diffraction (XRD and Raman spectrum. The acetylene sensing properties were investigated using different working temperatures and gas concentrations. An optimal temperature of 90 °C was determined, and the Ag–SnO2/rGO nanocomposite sensor exhibited excellent sensing behaviors towards acetylene, in terms of response, repeatability, stability and response/recovery characteristics, which were superior to the pure SnO2 and SnO2/rGO film sensors. The sensing mechanism of the Ag–SnO2/rGO sensor was attributed to the synergistic effect of the ternary nanomaterials, and the heterojunctions created at the interfaces between SnO2 and rGO. This work indicates that the Ag–SnO2/rGO nanocomposite is a good candidate for constructing a low-temperature acetylene sensor.

  18. Acetylene Gas-Sensing Properties of Layer-by-Layer Self-Assembled Ag-Decorated Tin Dioxide/Graphene Nanocomposite Film

    Science.gov (United States)

    Jiang, Chuanxing; Yin, Nailiang; Yao, Yao; Shaymurat, Talgar; Zhou, Xiaoyan

    2017-01-01

    This paper demonstrates an acetylene gas sensor based on an Ag-decorated tin dioxide/reduced graphene oxide (Ag–SnO2/rGO) nanocomposite film, prepared by layer-by-layer (LbL) self-assembly technology. The as-prepared Ag–SnO2/rGO nanocomposite was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray diffraction (XRD) and Raman spectrum. The acetylene sensing properties were investigated using different working temperatures and gas concentrations. An optimal temperature of 90 °C was determined, and the Ag–SnO2/rGO nanocomposite sensor exhibited excellent sensing behaviors towards acetylene, in terms of response, repeatability, stability and response/recovery characteristics, which were superior to the pure SnO2 and SnO2/rGO film sensors. The sensing mechanism of the Ag–SnO2/rGO sensor was attributed to the synergistic effect of the ternary nanomaterials, and the heterojunctions created at the interfaces between SnO2 and rGO. This work indicates that the Ag–SnO2/rGO nanocomposite is a good candidate for constructing a low-temperature acetylene sensor. PMID:28927021

  19. The effects of carbon distribution and thickness on the lithium storage properties of carbon-coated SnO_2 hollow nanofibers

    International Nuclear Information System (INIS)

    Zhou, Huimin; Li, Zhiyong; Qiu, Yiping; Xia, Xin

    2016-01-01

    To alleviate the enormous volume change problem of tin-based anodes for lithium ion batteries (LIBs), carbon-coated tin dioxide (SnO_2) hollow nanofibers were prepared by means of single-spinneret electrospinning followed by calcination and hydrothermal treatment. By varying the concentration of glucose and the reaction time during the hydrothermal coating process, the final product with different carbon distribution and thickness could be obtained. Galvanostatic charge/discharge was carried out to evaluate them as potential anode materials for LIBs. It was shown that the main effect of carbon distribution was to control the capacity retention rate, and the carbon thickness played the important role in lithium insertion/extraction properties. The optimum composite nanofibers could be prepared with glucose concentration of 10 mg/ml and hydrothermal time of 20 h, the carbon content and the specific surface area of which were 26.15% and 29.4 m"2/g, respectively. And this anode with both the carbon core and deposited thin carbon skin was able to deliver a high reversible capacity of 704.6 mAhg"−"1 and the capacity retention could retain 68.2% after 80 cycles. - Graphical abstract: Based on the electrochemical properties of carbon-coated hollow SnO2 anodes, how the carbon distribution and carbon thickness affect their performance are disscussed in groups. - Highlights: • The hollow SnO_2 nanofibers were carbon-coated by hydrothermal process. • The controlled distribution and thickness of carbon layer can be obtained. • The main effect of carbon distribution was to control the capacity retention rate. • The carbon thickness played the important role in lithium insertion/extraction properties.

  20. The effect of substrate temperature on atomic layer deposited zinc tin oxide

    Energy Technology Data Exchange (ETDEWEB)

    Lindahl, Johan, E-mail: johan.lindahl@angstrom.uu.se; Hägglund, Carl, E-mail: carl.hagglund@angstrom.uu.se; Wätjen, J. Timo, E-mail: timo.watjen@angstrom.uu.se; Edoff, Marika, E-mail: marika.edoff@angstrom.uu.se; Törndahl, Tobias, E-mail: tobias.torndahl@angstrom.uu.se

    2015-07-01

    Zinc tin oxide (ZTO) thin films were deposited on glass substrates by atomic layer deposition (ALD), and the film properties were investigated for varying deposition temperatures in the range of 90 to 180 °C. It was found that the [Sn]/([Sn] + [Zn]) composition is only slightly temperature dependent, while properties such as growth rate, film density, material structure and band gap are more strongly affected. The growth rate dependence on deposition temperature varies with the relative number of zinc or tin containing precursor pulses and it correlates with the growth rate behavior of pure ZnO and SnO{sub x} ALD. In contrast to the pure ZnO phase, the density of the mixed ZTO films is found to depend on the deposition temperature and it increases linearly with about 1 g/cm{sup 3} in total over the investigated range. Characterization by transmission electron microscopy suggests that zinc rich ZTO films contain small (~ 10 nm) ZnO or ZnO(Sn) crystallites embedded in an amorphous matrix, and that these crystallites increase in size with increasing zinc content and deposition temperature. These crystallites are small enough for quantum confinement effects to reduce the optical band gap of the ZTO films as they grow in size with increasing deposition temperature. - Highlights: • Zinc tin oxide thin films were deposited by atomic layer deposition. • The structure and optical properties were studied at different growth temperatures. • The growth temperature had only a small effect on the composition of the films. • Small ZnO or ZnO(Sn) crystallites were observed by TEM in zinc rich ZTO films. • The growth temperature affects the crystallite size, which influences the band gap.