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Sample records for in24 sn8 o48

  1. Phase behaviour, thermal expansion and compressibility of SnMo 2 O 8

    Energy Technology Data Exchange (ETDEWEB)

    Araujo, Luiza R.; Gallington, Leighanne C.; Wilkinson, Angus P.; Evans, John S.O. (Durham); (GIT)

    2018-02-01

    The phase behaviour and thermoelastic properties of SnMo2O8, derived from variable temperature and pressure synchrotron powder diffraction data, are reported. SnMo2O8 is a member of the AM2O8 family of negative thermal expansion (NTE) materials, but unexpectedly, has positive thermal expansion. Over the P-T space explored (298–513 K, ambient to 310 MPa) four different forms of SnMo2O8 are observed: α, β, γ and γ'. The γ to β transition is temperature-, pressure-, and time-dependent. SnMo2O8 is a much softer material (α and γ form have BT = 29 and 26 GPa at 298 K) than other members of the AM2O8 family. Counter-intuitively, its high temperature β phase becomes stiffer with increasing temperature (BT ~36 GPa at 490 K). The pressure dependence of the thermal expansion for each phase is reported.

  2. Ti-24Nb-4Zr-8Sn Alloy Pedicle Screw Improves Internal Vertebral Fixation by Reducing Stress-Shielding Effects in a Porcine Model.

    Science.gov (United States)

    Qu, Yang; Zheng, Shuang; Dong, Rongpeng; Kang, Mingyang; Zhou, Haohan; Zhao, Dezhi; Zhao, Jianwu

    2018-01-01

    To ensure the biomechanical properties of Ti-24Nb-4Zr-8Sn, stress-shielding effects were compared between Ti-24Nb-4Zr-8Sn and Ti-6Al-4V fixation by using a porcine model. Twelve thoracolumbar spines (T12-L5) of 12-month-old male pigs were randomly divided into two groups: Ti-24Nb-4Zr-8Sn (EG, n = 6) and Ti-6Al-4V (RG, n = 6) fixation. Pedicle screw was fixed at the outer edge of L4-5 vertebral holes. Fourteen measuring points were selected on the front of transverse process and middle and posterior of L4-5 vertebra. Electronic universal testing machine was used to measure the strain resistance of measuring points after forward and backward flexion loading of 150 N. Meanwhile, stress resistance was compared between both groups. The strain and stress resistance of measurement points 1, 2, 5, 6, 9, and 10-14 in Ti-24Nb-4Zr-8Sn fixation was lower than that of Ti-6Al-4V fixation after forward and backward flexion loading ( P Ti-24Nb-4Zr-8Sn fixation than that of Ti-6Al-4V fixation ( P Ti-24Nb-4Zr-8Sn internal fixation were less than that of Ti-6Al-4V internal fixation. These results suggest that Ti-24Nb-4Zr-8Sn elastic fixation has more biomechanical goals than conventional Ti-6Al-4V internal fixation by reducing stress-shielding effects.

  3. 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.

  4. Pulsed laser deposition of epitaxial Sr(RuxSn1-x)O3 thin film electrodes and KNbO3/Sr(RuxSn1-x)O3 bilayers

    International Nuclear Information System (INIS)

    Christen, H.M.; Boatner, L.A.; English, L.Q.; Geea, L.A.; Marrero, P.J.; Norton, D.P.

    1995-01-01

    Sr(Ru x Sn 1-x ) 3 is proposed as a new conducting oxide for use in epitaxial multilayer structures. The Sr(Ru o 48 Sn 0.52 )0 3 composition exhibits an excellent lattice match with (100)-oriented KTaO 3 , and films of this composition grown by pulsed laser deposition on KTaO 3 , SrTiO 3 , and LaAlO 3 substrates have been analyzed by X-ray diffraction, Rutherford backscattering/ion channeling, and resistivity measurements. Epitaxial KNbO 3 /Sr(Ru 0.48 Sn 0.52 )O 3 bilayers have been successfully grown

  5. Synthesis and characterization of Sn doped TiO{sub 2} photocatalysts: Effect of Sn concentration on the textural properties and on the photocatalytic degradation of 2,4-dichlorophenoxyacetic acid

    Energy Technology Data Exchange (ETDEWEB)

    Rangel-Vázquez, I.; Del Angel, G.; Bertin, V. [Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael, Atlixco No 1865, México 09340 D.F. (Mexico); González, F. [Departamento de Ingeniería de Procesos e Hidráulica, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael, Atlixco No 1865, México 09340 D.F. (Mexico); Vázquez-Zavala, A.; Arrieta, A. [Departamento de Química, Universidad Autónoma Metropolitana-Iztapalapa, Av. San Rafael, Atlixco No 1865, México 09340 D.F. (Mexico); Padilla, J.M. [Universidad Tecnológica del Centro de Veracruz, Área de Tecnología, Av. Universidad Carretera Federal Cuitláhuac-La Tinaja No. 350, Cuitláhuac, Veracruz 94910 (Mexico); Barrera, A. [Universidad de Guadalajara, Centro Universitario de la Ciénega, Av. Universidad, Número 1115, Col. Linda Vista, Apdo. Postal 106, Ocotlán Jal. (Mexico); Ramos-Ramirez, E. [Departamento de Química, División de Ciencias Naturales y Exactas, Campus Guanajuato de la Universidad de Guanajuato Noria Alta S/N, Col. Noria Alta, Guanajuato, Gto. C.P. 36050 (Mexico)

    2015-09-15

    Abstract: TiO{sub 2} and Sn-doped TiO{sub 2} materials were prepared by sol–gel method using titanium and tin alkoxides at different Sn concentration (0.1 mol%, 0.5 mol%, 1 mol%, 3 mol% and 5 mol%). Samples were characterized by thermo gravimetric analyzer with differential scanning calorimeter (TGA–DSC), X-ray Rietveld refinement, N{sub 2} adsorption (BET), transmission electron microscopy (TEM), UV–vis spectroscopies technology and Raman spectroscopy. Only anatase phase was observed in pure TiO{sub 2}, whereas anatase and brookite were obtained in Sn-doped TiO{sub 2} samples. Sn dopant acts as a promoter in phase transformation of TiO{sub 2}. The Rietveld refinements method was used to determine the relative weight of anatase and brookite, and crystallite size as a function of Sn concentration after calcination of samples at 673 K. It was also demonstrated the incorporation of Sn{sup 4+} into the anatase TiO{sub 2} structure. Sn{sup 4+} inhibits the growth of TiO{sub 2} crystallite size, which leads to an increase of the specific surface area of TiO{sub 2}. From XRD analysis, the solid solution limit of Sn{sup 4+} into TiO{sub 2} is 5 mol% Sn. The photocatalytic activity on Sn{sup 4+} doped TiO{sub 2} was determined for the 2,4-dichlorophenoxyacetic acid reaction. The maximum in activity was attributed to the coexistence of anatase and brookite phases in the appropriate ratio and crystallite size.

  6. P-type SnO thin films and SnO/ZnO heterostructures for all-oxide electronic and optoelectronic device applications

    Energy Technology Data Exchange (ETDEWEB)

    Saji, Kachirayil J. [Nanostructured Materials Research Laboratory, Department of Materials Science & Engineering, University of Utah, Salt Lake City, UT 84112 (United States); Department of Physics, Govt. Victoria College, University of Calicut, Palakkad 678 001 (India); Venkata Subbaiah, Y.P. [Nanostructured Materials Research Laboratory, Department of Materials Science & Engineering, University of Utah, Salt Lake City, UT 84112 (United States); Department of Physics, Yogi Vemana University, Kadapa, Andhra Pradesh 516003 (India); Tian, Kun [Nanostructured Materials Research Laboratory, Department of Materials Science & Engineering, University of Utah, Salt Lake City, UT 84112 (United States); Tiwari, Ashutosh, E-mail: tiwari@eng.utah.edu [Nanostructured Materials Research Laboratory, Department of Materials Science & Engineering, University of Utah, Salt Lake City, UT 84112 (United States)

    2016-04-30

    Tin monoxide (SnO) is considered as one of the most important p-type oxides available to date. Thin films of SnO have been reported to possess both an indirect bandgap (~ 0.7 eV) and a direct bandgap (~ 2.8 eV) with quite high hole mobility (~ 7 cm{sup 2}/Vs) values. Moreover, the hole density in these films can be tuned from 10{sup 15}–10{sup 19} cm{sup −3} just by controlling the thin film deposition parameters. Because of the above attributes, SnO thin films offer great potential for fabricating modern electronic and optoelectronic devices. In this article, we are reviewing the most recent developments in this field and also presenting some of our own results on SnO thin films grown by pulsed laser deposition technique. We have also proposed a p–n heterostructure comprising of p-type SnO and n-type ZnO which can pave way for realizing next-generation, all-oxide transparent electronic devices. - Highlights: • We reviewed recent developments on p-type SnO thin film research. • Discussed the optical and electrical properties of SnO thin films • Bipolar conduction in SnO is discussed. • Optoelectronic properties of SnO–ZnO composite system are discussed. • Proposed SnO–ZnO heterojunction band structure.

  7. Photoreduction of Carbon Dioxide to Methane Over Sb1.5Sn8.5-x Ti x O19.0 with High Conductivity.

    Science.gov (United States)

    Do, Jeong Yeon; Kwak, Byeong Sub; Kang, Misook

    2018-09-01

    In order to enhance the photoreduction of CO2 to CH4, a new type of photocatalyst, Sb1.5Sn8.5-xTixO19.0, with high conductivity and low bandgap was developed by partially incorporating Ti into the framework of Sb1.5Sn8.5O19.0 (antimony-doped tin oxide, ATO) using a controlled hydrothermal method. XRD and TEM analyses indicated that the Sb1.5Sn8.5-xTixO19.0 particles exhibited a tetragonal crystal structure and were approximately 20 nm in size. Furthermore, the bandgap and conductivity of these materials increased with increasing Ti content. A study of the photoreduction of CO2 with H2O revealed a remarkable increase in the generation of CH4 over the Sb1.5Sn8.5-xTixO19.0 catalysts. In particular, CH4 generation was the highest when Sb1.5Sn8.5Ti1.0O19.0 was used as the photocatalyst, and was three-fold higher than that achieved by using anatase TiO2. Photoluminescence studies showed that the enhanced photocatalytic activity of the Sb1.5Sn8.5-xTixO19.0 materials could be attributed to the interfacial transfer of photogenerated charges, which led to an effective charge separation and inhibition of the recombination of photogenerated electron-hole (e-/h+) pairs.

  8. SnO and SnO·CoO nanocomposite as high capacity anode materials for lithium ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Das, B., E-mail: bijoy822000@gmail.com; Reddy, M.V.; Chowdari, B.V.R, E-mail: phychowd@nus.edu.sg

    2016-02-15

    Highlights: • The preparation methods are simple, low cost and can be scaled up for large production. • SnO is cheap, non-toxic and eco-friendly. • SnO shows high reversible capacity (Theoretical reversible capacity: 875 mA h g{sup −1}). • We showed high reversible capacity and columbic efficiency for SnO and SnO based composites. • We addressed the capacity degradation by introducing secondary phase (CoO and CNT etc.) - Abstract: We prepared SnO nanoparticles (SnO–S) and SnO·CoO nanocomposites (SnO·CoO–B) as anodes for lithium ion batteries (LIBs) by chemical and ball-milling approaches, respectively. They are characterized by X-ray diffraction and TEM techniques. The Li- storage performance are evaluated by galvanostatic cycling and cyclic voltammetry. The SnO–S and SnO·CoO–B showed improved cycling performance due to their finite particle size (i.e. nano-size) and presence of secondary phase (CoO). Better cycling stability is noticed for SnO·CoO–B with the expense of their reversible capacity. Also, addition of carbon nanotubes (CNT) to SnO–S further improved the cycling performance of SnO–S. When cycled at 60 mA g{sup −1}, the first-cycle reversible capacities of 635, 590 and 460 (±10) mA h g{sup −1} are noticed for SnO–S, SnO@CNT and SnO·CoO–B, respectively. The capacity fading observed are 3.7 and 1.8 mA h g{sup −1} per cycle for SnO–S and SnO@CNT, respectively; whereas 1–1.2 mA h g{sup −1} per cycle for SnO·CoO–B. All the samples show high coulombic efficiency, 96–98% in the range of 5–50 cycles.

  9. Ultraviolet emission from low resistance Cu2SnS3/SnO2 and CuInS2/Sn:In2O3 nanowires

    Directory of Open Access Journals (Sweden)

    E. Karageorgou

    2014-11-01

    Full Text Available SnO2 and Sn:In2O3 nanowires were grown on Si(001, and p-n junctions were fabricated in contact with p-type Cu2S which exhibited rectifying current–voltage characteristics. Core-shell Cu2SnS3/SnO2 and CuInS2/Sn:In2O3 nanowires were obtained by depositing copper and post-growth processing under H2S between 100 and 500 °C. These consist mainly of tetragonal rutile SnO2 and cubic bixbyite In2O3. We observe photoluminescence at 3.65 eV corresponding to band edge emission from SnO2 quantum dots in the Cu2SnS3/SnO2 nanowires due to electrostatic confinement. The Cu2SnS3/SnO2 nanowires assemblies had resistances of 100 Ω similar to CuInS2/In2O3 nanowires which exhibited photoluminescence at 3.0 eV.

  10. Temperature compensation effects of TiO2 on Ca[(Li1/3Nb2/3)0.8Sn0.2]O3-δ microwave dielectric ceramic

    Science.gov (United States)

    Hu, Mingzhe; Wei, Huanghe; Xiao, Lihua; Zhang, Kesheng; Hao, Yongde

    2017-10-01

    The crystal structure and dielectric properties of TiO2-modified Ca[(Li1/3Nb2/3)0.8Sn0.2]O3-δ microwave ceramics are investigated in the present paper. The crystal structure is probed by XRD patterns and their Rietveld refinement, results show that a single perovskite phase is formed in TiO2-modified Ca[(Li1/3Nb2/3)0.8Sn0.2]O3-δ ceramics with the crystal structure belonging to the orthorhombic Pbnm 62 space group. Raman spectra results indicate that the B-site order-disorder structure transition is a key point to the dielectric loss of TiO2-modified Ca[(Li1/3Nb2/3)0.8Sn0.2]O3-δ ceramics at microwave frequencies. After properly modified by TiO2, the large negative temperature coefficient of Ca[(Li1/3Nb2/3)0.8Sn0.2]O3-δ ceramic can be compensated and the optimal microwave dielectric properties can reach 𝜀r = 25.66, Qf = 18,894 GHz and TCF = -6.3 ppm/∘C when sintered at 1170∘C for 2.5 h, which manifests itself for potential use in microwave dielectric devices for modern wireless communication.

  11. Spectral and ion emission features of laser-produced Sn and SnO2 plasmas

    Science.gov (United States)

    Hui, Lan; Xin-Bing, Wang; Du-Luo, Zuo

    2016-03-01

    We have made a detailed comparison of the atomic and ionic debris, as well as the emission features of Sn and SnO2 plasmas under identical experimental conditions. Planar slabs of pure metal Sn and ceramic SnO2 are irradiated with 1.06 μm, 8 ns Nd:YAG laser pulses. Fast photography employing an intensified charge coupled device (ICCD), optical emission spectroscopy (OES), and optical time of flight emission spectroscopy are used as diagnostic tools. Our results show that the Sn plasma provides a higher extreme ultraviolet (EUV) conversion efficiency (CE) than the SnO2 plasma. However, the kinetic energies of Sn ions are relatively low compared with those of SnO2. OES studies show that the Sn plasma parameters (electron temperature and density) are lower compared to those of the SnO2 plasma. Furthermore, we also give the effects of the vacuum degree and the laser pulse energy on the plasma parameters. Project supported by the National Natural Science Foundation of China (Grant No. 11304235) and the Director Fund of WNLO, China.

  12. Microwave-Assisted Synthesis of Graphene-SnO2 Nanocomposites and Their Applications in Gas Sensors.

    Science.gov (United States)

    Kim, Hyoun Woo; Na, Han Gil; Kwon, Yong Jung; Kang, Sung Yong; Choi, Myung Sik; Bang, Jae Hoon; Wu, Ping; Kim, Sang Sub

    2017-09-20

    We obtained extremely high and selective sensitivity to NO 2 gas by fabricating graphene-SnO 2 nanocomposites using a commercial microwave oven. Structural characterization revealed that the products corresponded to agglomerated structures of graphene and SnO 2 particles, with small secondary SnO x (x ≤ 2) nanoparticles deposited on the surfaces. The overall oxygen atomic ratio was decreased with the appearance of an SnO x (x graphene-SnO 2 nanocomposites, with the graphene promoting efficient transport of the microwave energy, evaporation and redeposition of SnO x nanoparticles were facilitated. The graphene-SnO 2 nanocomposites exhibited a high sensor response of 24.7 for 1 ppm of NO 2 gas, at an optimized temperature of 150 °C. The graphene-SnO 2 nanocomposites were selectively sensitive to NO 2 gas, in comparison with SO 2 , NH 3 , and ethanol gases. We suggest that the generation of SnO x nanoparticles and the SnO x phase in the matrix results in the formation of SnO 2 /SnO 2 homojunctions, SnO 2 /SnO x (x graphene heterojunctions, which are responsible for the excellent sensitivity of the graphene-SnO 2 nanocomposites to NO 2 gas. In addition, the generation of surface Sn interstitial defects is also partly responsible for the excellent NO 2 sensing performance observed in this study.

  13. Oxothiomolybdenum derivatives of the superlacunary crown heteropolyanion {P8W48}: structure of [K4{Mo4O4S4(H2O)3(OH)2}2(WO2)(P8W48O184)]30– and studies in solution.

    Science.gov (United States)

    Korenev, Vladimir S; Floquet, Sébastien; Marrot, Jérôme; Haouas, Mohamed; Mbomekallé, Israël-Martyr; Taulelle, Francis; Sokolov, Maxim N; Fedin, Vladimir P; Cadot, Emmanuel

    2012-02-20

    Reaction of the cyclic lacunary [H(7)P(8)W(48)O(184)](33-) anion (noted P(8)W(48)) with the [Mo(2)S(2)O(2)(H(2)O)(6)](2+) oxothiocation led to two compounds, namely, [K(4){Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2)(WO(2))(P(8)W(48)O(184))](30-) (denoted 1) and [{Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2)(P(8)W(48)O(184))](36-) (denoted 2), which were characterized in the solid state and solution. In the solid state, the structure of [K(4){Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2)(WO(2))(P(8)W(48)O(184))](30-) reveals the presence of two disordered {Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2+) "handles" connected on both sides of the P(8)W(48) ring. Such a disorder is consistent with the presence of two geometrical isomers where the relative disposition of the two {Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2+) handles are arranged in a perpendicular or parallel mode. Such an interpretation is fully supported by (31)P and (183)W NMR solution studies. The relative stability of both geometrical isomers appears to be dependent upon the nature of the internal alkali cations, i.e., Na(+) vs K(+), and increased lability of the two {Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2+) handles, compared to the oxo analogous, was clearly identified by significant broadening of the (31)P and (183)W NMR lines. Solution studies carried out by UV-vis spectroscopy showed that formation of the adduct [{Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2)(P(8)W(48)O(184))](36-) occurs in the 1.5-4.7 pH range and corresponds to a fast and quantitative condensation process. Furthermore, (31)P NMR titrations in solution reveal formation of the "monohandle" derivative [{Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(P(8)W(48)O(184))](38-) as an intermediate prior to formation of the "bishandle" derivatives. Furthermore, the electrochemical behavior of [{Mo(4)O(4)S(4)(H(2)O)(3)(OH)(2)}(2)(P(8)W(48)O(184))](36-) was studied in aqueous medium and compared with the parent anion P(8)W(48).

  14. A detailed study on Sn4+ doped ZnO for enhanced photocatalytic degradation

    Science.gov (United States)

    Beura, Rosalin; Pachaiappan, R.; Thangadurai, P.

    2018-03-01

    The samples of Sn4+ doped (1, 5, 10, 15, 20 & 30%) ZnO nanostructures were synthesized by a low temperature hydrothermal method. Structural analysis by XRD and Raman spectroscopy showed the hexagonal wurtzite phase of ZnO and the formation of a secondary phase Zn2SnO4 beyond 10% doping of Sn4+. Microstructural analysis by TEM also confirmed the wurtzite ZnO with rod as well as particle like structure. Presence of various functional groups (sbnd OH, sbnd CH, Znsbnd O) were confirmed by FTIR. Optical properties were studied by UV-vis absorption, photoluminescence emission spectroscopies and lifetime measurement. Band gap of the undoped and Sn4+ doped ZnO were analyzed by Tauc plot and it was observed that the band gap of the materials had slightly decreased from 3.2 to 3.16 eV and again increased to 3.23 eV with respect to the increase in the doping concentration from 1 to 30%. A significant change was also noticed in the photoluminescence emission properties of ZnO i.e. increase in the intensity of NBE emission and decrease in DLE, on subject to Sn4+ doping. Average PL lifetime had increased from 29.45 ns for ZnO to 30.62 ns upon 1% Sn ion doping in ZnO. Electrical properties studied by solid state impedance spectroscopy showed that the conductivity had increased by one order of magnitude (from 7.48×10-8 to 2.21×10-7 S/cm) on Sn4+ doping. Photocatalytic experiments were performed on methyl orange (MO) as a model industrial dye under UV light irradiation for different irradiation times. The optimum Sn4+ content in order to achieve highest photocatalytic activity was found to be 1% Sn 4+ doping. The enhancement was achieved due to a decrease in the band gap favoring the generation of electron-hole pairs and the enhanced PL life time that delays the recombination of these charge carrier formation. The third reason was that the increased electrical conductivity that indicated the faster charge transfer in this material to enhance the photocatalytic activity. The Sn

  15. Microstructural investigation and SnO nanodefects in spray-pyrolyzed SnO2 thin films

    DEFF Research Database (Denmark)

    Thanachayanont, Chanchana; Yordsri, Visittapong; Boothroyd, Chris

    2011-01-01

    Spray pyrolysis is one of the most cost-effective methods to prepare SnO2 films due to its ability to deposit large uniform area, low fabrication cost, simplicity and low deposition temperature. Conventionally, scanning electron microscopy (SEM) and X-Ray Diffraction (XRD) are routinely used...... diffraction (CBED). It was found that large grain-size vertically-aligned columnar SnO2 grains were formed after a few layers of small grain-size randomly oriented SnO2 grains. Moreover, CBED showed the presence of SnO nanodefects that had not been reported before and could not be detected by SEM or XRD....

  16. Rational design of Sn/SnO{sub 2}/porous carbon nanocomposites as anode materials for sodium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Li, Xiaojia [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Li, Xifei, E-mail: xfli2011@hotmail.com [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Center for Advanced Energy Materials and Devices, Xi’an University of Technology, Xi’an 710048 (China); Key Laboratory of Advanced Energy Materials Chemistry (Ministry of Education), Collaborative Innovation Center of Chemical Science and Engineering, College of Chemistry, Nankai University, Tianjin 300071 (China); Fan, Linlin; Yu, Zhuxin; Yan, Bo; Xiong, Dongbin; Song, Xiaosheng; Li, Shiyu [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Adair, Keegan R. [Nanomaterials and Energy Lab., Department of Mechanical and Materials Engineering, Western University, London, Ontario N6A 5B9 (Canada); Li, Dejun, E-mail: dejunli@mail.tjnu.edu.cn [Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China); Sun, Xueliang, E-mail: xsun9@uwo.ca [Nanomaterials and Energy Lab., Department of Mechanical and Materials Engineering, Western University, London, Ontario N6A 5B9 (Canada); Tianjin International Joint Research Centre of Surface Technology for Energy Storage Materials, College of Physics and Materials Science, Tianjin Normal University, Tianjin 300387 (China)

    2017-08-01

    Highlights: • Sn/SnO{sub 2}/porous carbon nanocomposites are rationally designed via a facile strategy. • The porous carbon mitigates the volume change and poor conductivity of Sn/SnO{sub 2}. • The nanocomposites exhibit the enhanced sodium storage performance. - Abstract: Sodium-ion batteries (SIBs) have successfully attracted considerable attention for application in energy storage, and have been proposed as an alternative to lithium ion batteries (LIBs) due to the abundance of sodium resources and low price. Sn has been deemed as a promising anode material in SIBs which holds high theoretical specific capacity of 845 mAh g{sup −1}. In this work we design nanocomposite materials consisting of porous carbon (PC) with SnO{sub 2} and Sn (Sn/SnO{sub 2}/PC) via a facile reflux method. Served as an anode material for SIBs, the Sn/SnO{sub 2}/PC nanocomposite delivers the primary discharge and charge capacities of 1148.1 and 303.0 mAh g{sup −1}, respectively. Meanwhile, it can preserve the discharge capacity approximately of 265.4 mAh g{sup −1} after 50 cycles, which is much higher than those of SnO{sub 2}/PC (138.5 mAh g{sup −1}) and PC (92.2 mAh g{sup −1}). Furthermore, the Sn/SnO{sub 2}/PC nanocomposite possesses better cycling stability with 77.8% capacity retention compared to that of SnO{sub 2}/PC (61.88%) over 50 cycles. Obviously, the Sn/SnO{sub 2}/PC composite with excellent electrochemical performance shows the great possibility of application in SIBs.

  17. Martensitic transition, inverse magnetocaloric effect and shape memory characteristics in Mn{sub 48−x}Cu{sub x}Ni{sub 42}Sn{sub 10} Heusler alloys

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Changqin [Department of Physics, Shanghai University, Shanghai 200444 (China); Li, Zhe [Reasearch center for magnetic materials and devices & Key Laboratory for Advanced Functional and Low Dimensional Materials of Yunnan Higher Education Institute, Qujing Normal University, Qujing 655011 (China); Zhang, Yuanlei [Department of Physics, Shanghai University, Shanghai 200444 (China); Reasearch center for magnetic materials and devices & Key Laboratory for Advanced Functional and Low Dimensional Materials of Yunnan Higher Education Institute, Qujing Normal University, Qujing 655011 (China); Liu, Yang; Sun, Junkun; Huang, Yinsheng; Kang, Baojuan [Department of Physics, Shanghai University, Shanghai 200444 (China); Xu, Kun [Reasearch center for magnetic materials and devices & Key Laboratory for Advanced Functional and Low Dimensional Materials of Yunnan Higher Education Institute, Qujing Normal University, Qujing 655011 (China); Deng, Dongmei [Department of Physics, Shanghai University, Shanghai 200444 (China); Jing, Chao, E-mail: cjing@staff.shu.edu.cn [Department of Physics, Shanghai University, Shanghai 200444 (China)

    2017-03-01

    In this paper, we have systematically prepared a serials of polycrystalline Mn{sub 48−x}Cu{sub x}Ni{sub 42}Sn{sub 10} alloys (x=0, 1, 3, 5, 6, 8, 10 and 12) and investigated the influence of the Cu doping on martensitic transition (MT) as well as magnetic properties. Experimental results indicate that the MT temperature and the martensite Curie temperature (T{sub c}{sup M}) shift to high temperature with increasing the substitution of Cu (from Mn rich alloy to Ni rich alloy), while the austenite Curie temperature (T{sub c}{sup A}) is almost unchanged. It was found that the structures undergo L2{sub 1} and 4O with the increasing of Cu concentration near room temperature. Therefore, the magnetostructural transition can be tuned by appropriate Cu doping in these alloys. Moreover, we mainly studied the multiple functional properties for inverse magnetocaloric effect and shape memory characteristics associated with the martensitic transition. A large positive isothermal entropy change of Mn{sub 48}Ni{sub 42}Sn{sub 10} was obtained, and the maximum transition entropy change achieves about 48 J/kg K as x=8. In addition, a considerable temperature-induced spontaneous strain with the value of 0.16% was obtained for Mn{sub 48}Ni{sub 42}Sn{sub 10} alloys.

  18. Superhydrophilic SnO{sub 2} nanosheet-assembled film

    Energy Technology Data Exchange (ETDEWEB)

    Masuda, Yoshitake, E-mail: masuda-y@aist.go.jp; Kato, Kazumi

    2013-10-01

    SnO{sub 2} films were fabricated on fluorine-doped tin oxide (FTO) substrates in aqueous solutions. The films of about 800 nm in thickness grew in the solutions containing SnF{sub 2} of 25 mM at 90 °C for 24 h. They consisted of nanosheets of about 5–10 nm in thickness and about 100–1600 nm in plane size. The films had gradient structure of nanosheets. Smaller nanosheets formed dense structures in a bottom area, while larger nanosheets formed porous structures in a surface area of the films. The SnO{sub 2} films showed higher transparency than bare FTO substrates in a visible light region of 470 to 850 nm. Decrease of reflectance increased transparency. The SnO{sub 2} films had superhydrophilic surfaces of static contact angle below 1°. Nanosheet-assembled structures contributed high hydrophilicity. The surfaces were further modified with light irradiation. High speed camera observation showed that spread speed of water was improved with the irradiation. Removal of surface adsorbed organic molecules and increase in the number of hydroxyl groups brought superhydrophilicity and high spread speed. - Highlights: ► SnO{sub 2} nanosheet films were prepared from aqueous solutions. ► The antireflective films showed superhydrophilicity. ► Crystal growth mechanism of the gradient structures is discussed.

  19. Synthesis, structural and paramagnetic properties of SnO{sub 2} doped NiO nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Islam, I., E-mail: ishtihadahislam@gmail.com; Dwivedi, Sonam; Dar, Hilal A.; Dar, M. A.; Varshney, Dinesh, E-mail: vdinesh33@rediffmail.com [School of Physics, Vigyan Bhawan, Devi Ahilya University, Khandwa Road Campus, Indore 452001 (India)

    2016-05-06

    In this work, Sn doped NiO nanoparticles were synthesized by co-precipitation route to explore the impact of doping on lattice structure, dielectric constant and magnetization. X-ray diffraction analysis confirmed cubic (Fd-3m) structure of Sn doped NiO. Average crystallite size decreases from 78.2 nm (Ni{sub 0.95}Sn{sub 0.05}O) to 64.23 nm (Ni{sub 0.8}Sn{sub 0.2}O). Scanning electron microscopy images confirm that nanocrystals have agglomerated spherical morphology. The Raman spectrum exhibits a strong, broad peak at 410 cm{sup -1} and is attributed to the Ni-O stretching mode and doped samples show a blue shift. The dielectric constants at about 1 Hz are measured to be about 1.795, 1.030, 0.442, and 0.302 × 10{sup 3} Ni{sub 1-x}Sn{sub x}O (x = 0.05, 0.1, 0.15, 0.2), respectively. The dielectric constant in nanoparticles of doped Ni{sub 1-x}Sn{sub x}O is three orders of magnitude higher as compared to pure NiO ceramics. The nature of magnetization - applied field (M-H) infers paramagnetic behaviour for Sn doped NiO nanoparticles.

  20. Electrical resistivity in Zr48Nb8Cu12Fe8Be24 glassy and crystallized alloys

    Science.gov (United States)

    Bai, H. Y.; Tong, C. Z.; Zheng, P.

    2004-02-01

    The electrical resistivity of Zr48Nb8Cu12Fe8Be24 bulk metallic glassy and crystallized alloys in the temperature range of 4.2-293 K is investigated. It is found that the resistivity in glassy and crystallized states shows opposite temperature coefficients. For the metallic glass, the resistivity shows a negative logarithmic dependence at temperatures below 16 K, whereas it has more normal behavior for the crystallized alloy. At higher temperatures, the resistivity in both glassy and crystallized alloys shows dependence upon both T and T2, but the signs of the T and T2 terms are opposite. The results are interpreted in terms of scattering from two-level tunneling states in glasses and the generalized Ziman diffraction model.

  1. Growth and characterization of tin oxide thin films and fabrication of transparent p-SnO/n-ZnO p–n hetero junction

    Energy Technology Data Exchange (ETDEWEB)

    Sanal, K.C., E-mail: sanalcusat@gmail.com [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Kerala 682 022 (India); Inter University Center for Nanomaterials and Devices (IUCND), Cochin University of Science and Technology (India); Jayaraj, M.K. [Nanophotonic and Optoelectronic Devices Laboratory, Department of Physics, Cochin University of Science and Technology, Kerala 682 022 (India)

    2013-07-01

    Highlights: • Growth of p-type semiconducting SnO thin films by rf sputtering. • Varying the type of charge carriers with oxygen partial pressure. • Atomic percentage of SnO{sub x} thin films from the XPS analysis. • Demonstration of transparent p–n hetero junctions fabricated in the structure glass/ITO/n-ZnO/p-SnO. -- Abstract: p-Type and n-type tin oxide thin films were deposited by rf-magnetron sputtering of metal tin target by varying the oxygen pressure. Chemical composition of SnO thin film according to the intensity of the XPS peak is about 48.85% and 51.15% for tin and oxygen respectively. Nearest neighbor distance of the atoms calculated from SAED patterns is 2.9 Åand 2.7 Åfor SnO and SnO{sub 2} respectively. The Raman scattering spectrum obtained from SnO thin films showed two peaks, one at 113 cm{sup −1} and the other at 211 cm{sup −1}. Band gap of as-deposited SnO{sub x} thin films vary from 1.6 eV to 3.2 eV on varying the oxygen partial pressure from 3% to 30% which indicates the oxidization of metallic phase Sn to SnO and SnO{sub 2}. p-Type conductivity of SnO thin films and n-type conductivity of SnO{sub 2} thin films were confirmed through Hall coefficient measurement. Transparent p–n hetero junction fabricated in the structure glass/ITO/n-ZnO/p-SnO shows rectification with forward to reverse current ratio as 12 at 4.5 V.

  2. Zn{sub 2}SnO{sub 4}-SnO{sub 2} heterojunction nanocomposites for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Li Bihui; Luo Lijuan; Xiao Ting; Hu Xiaoyan [Institute of Nano-science and Technology, Central China Normal University, Wuhan, 430079 (China); Lu Lu; Wang, Jianbo [Department of Physics, Wuhan University, Wuhan 430072 (China); Tang Yiwen, E-mail: ywtang@phy.ccnu.edu.cn [Institute of Nano-science and Technology, Central China Normal University, Wuhan, 430079 (China)

    2011-02-03

    Graphical abstract: Display Omitted Research highlights: > The ZTO-SnO{sub 2} based DSSC shows superior photovoltaic performance than single phase ZTO or Pm-ZTO-SnO{sub 2} (physical mixture of ZTO and SnO{sub 2} nanoparticles having the same ZTO/SnO{sub 2} composition) based DSSC. > The obvious improvement in the photovoltaic performance is mainly ascribed to the efficient injected electrons transfer between the two materials via heterojunctions and consequent suppress the recombination. - Abstract: Zn{sub 2}SnO{sub 4}-SnO{sub 2} heterojunction nanocomposites (ZTO-SnO{sub 2}) with high mass amount of ZTO were synthesized by a two-step technique. The route involves firstly the synthesis of monodispersed ZnSn(OH){sub 6} nanocubes with a 50-60 nm edge length as precursors by simple coprecipitation of Na{sub 2}SnO{sub 3}.3H{sub 2}O and ZnCl{sub 2} aqueous solution, assisted by ultrasonic treatment and then followed by calcination of the precursors at 800 deg. C under N{sub 2} atmosphere. The as-synthesized nanoparticles were characterized by X-ray diffractometer (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). Heterojunction between ZTO and SnO{sub 2} nanoparticle was confirmed by the electron energy loss spectroscopy (EELS) elemental mapping and high-resolution TEM (HRTEM). The photovoltaic performance of the ZTO-SnO{sub 2} based DSSC was examined by measuring the J-V curves both in dark and under illumination. The results show that the ZTO-SnO{sub 2} based DSSC exhibits superior photovoltaic performance as compared to the single phase ZTO based DSSCs. Under illumination of AM 1.5 simulated sunlight (100 mW/cm{sup 2}), the open circuit voltage of the cell based on ZTO-SnO{sub 2} is 706 mV, the short-current density is 2.85 mA/cm{sup 2}, and the efficiency is 1.29% which is increased by 43% from 0.90% to 1.29% compared with pure ZTO. The formation of the heterojunctions between ZTO and SnO{sub 2} nanoparticles is believed to reduce

  3. Synthesis of polyaniline/SnO2 nanocomposite and its improved electrochemical performance

    International Nuclear Information System (INIS)

    Luo, Zhenyu; Zhu, Yinhai; Liu, Enhui; Hu, Tiantian; Li, Zengpeng; Liu, Tiantian; Song, Longchu

    2014-01-01

    Highlights: • Supercapacitors based on PANI/SnO 2 nanocomposite were reported. • Supercapacitors using this material gave a specific capacitance of 501 F g −1 . • Capacitance retention was 85.8% over 2000 charge–discharge cycles. - Abstract: SnO 2 was prepared by the hydrothermal route. Aniline monomer was polymerized in the suspension of SnO 2 to form inorganic–organic nanocomposite materials, in which SnO 2 particles were embedded within polyaniline (PANI). Morphological and structural characterizations of the prepared samples were carried out using scanning electron microscope; transmission electron microscope; power X-ray diffraction and Fourier transform infrared spectroscopy. Their electrochemical properties were also investigated using cyclic voltammetry, galvanostatic charge–discharge and electrochemical impedance spectroscopy. The as-prepared nanocomposites had excellent properties in the capacitance, and its specific capacitance was up to 501 F g −1 with a specific energy density of 66.8 W h kg −1 at a power density of 960.6 W kg −1 . The device fulfilled the requirement of long durability necessary for an energy storage system, since after 2000 galvanostatic charge–discharge cycles, retention of 85.8% in capacitance was observed. These results indicated that the PANI/SnO 2 had a synergistic effect of the complementary properties of both components

  4. Nano-grain SnO{sub 2} electrodes for high conversion efficiency SnO{sub 2}-DSSC

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jung-Hoon; Shin, Yu-Ju [Department of Chemistry, the Catholic University of Korea, Bucheon, Gyeonggi-do 422-743 (Korea, Republic of); Park, Nam-Gyu [School of Chemical Engineering, Sungkyunkwan University, Suwon, Gyeonggi-do 440-746 (Korea, Republic of)

    2011-01-15

    The nano-grain ZnO/SnO{sub 2} composite electrode was prepared by adding 5 w% of the 200-250 nm ZnO particles to the 5 nm SnO{sub 2} colloid in the presence of hydroxypropylcellulose (M.W.=80,000). The nano-grain SnO{sub 2} electrode was obtained by removing the ZnO particles from the composite electrode using acetic acid. The FE-SEM micrographs revealed that both electrodes consisted of interconnected nano-grains that were ca. 800 nm in size, and the large pores between the grains furnished the wide electrolyte diffusion channels within the electrodes. The photovoltaic properties of the nano-grain electrodes were investigated by measuring the I-V behaviors, the IPCE spectra and the ac-impedance spectra. The nano-grain electrodes exhibited remarkably improved conversion efficiencies of 3.96% for the composite and 2.98% for the SnO{sub 2} electrode compared to the value of 1.66% for the usual nano-particle SnO{sub 2} electrode. The improvement conversion efficiencies were mainly attributed to the formation of nano-grains, which facilitated the electron diffusion within the grains. The improved electrolyte diffusion as well as the light-scattering effects enhanced the photovoltaic performance of the SnO{sub 2} electrode. (author)

  5. Et2NH2C6H3(CO23SnBr2.4H2O: SYNTHESIS AND INFRARED STUDY

    Directory of Open Access Journals (Sweden)

    DAOUDA NDOYE

    2014-01-01

    Full Text Available The title compound has been obtained on allowing [C6H3(CO23(Et2NH23] to react with SnBr4. The molecular structure of Et2NH2C6H3(CO23SnBr2.4H2O has been determined on the basis of the infrared data. The suggested structure is a dimer in which each tin atom is hexacoordinated by two chelating C6H3(CO233- anions and two Br atoms. Cy2NH2+cations are involved through hydrogen bonds with non-coordinating CO2 groups. The suggested structure is a cage.

  6. Synthesis, Characterization, and Photocatalytic Activity of Zn-Doped SnO2/Zn2SnO4 Coupled Nanocomposites

    Directory of Open Access Journals (Sweden)

    Tiekun Jia

    2014-01-01

    Full Text Available Zn-doped SnO2/Zn2SnO4 nanocomposites were prepared via a two-step hydrothermal synthesis method. The as-prepared samples were characterized by X-ray diffraction (XRD, field-emission scanning electron microscopy (FESEM, transmission electron microscopy (TEM, UV-vis diffuse reflection spectroscopy, and adsorption-desorption isotherms. The results of FESEM and TEM showed that the as-prepared Zn-doped SnO2/Zn2SnO4 nanocomposites are composed of numerous nanoparticles with the size ranging from 20 nm to 50 nm. The specific surface area of the as-prepared Zn-doped SnO2/Zn2SnO4 nanocomposites is estimated to be 71.53 m2/g by the Brunauer-Emmett-Teller (BET method. The photocatalytic activity was evaluated by the degradation of methylene blue (MB, and the resulting showed that Zn-doped SnO2/Zn2SnO4 nanocomposites exhibited excellent photocatalytic activity due to their higher specific surface area and surface charge carrier transfer.

  7. Ni doping effect on the electronic and sensing properties of 2D SnO2

    Science.gov (United States)

    Patel, Anjali; Roondhe, Basant; Jha, Prafulla K.

    2018-05-01

    In the present work using state of art first principles calculations under the frame work of density functional theory the effect of Nickel (Ni) doping on electronic as well as sensing properties of most stable two dimensional (2D) T-SnO2 phase towards ethanol (C2H5OH) has been observed. It has been found that Ni atom when dope on T-SnO2 causes prominent decrement in the band gap from 2.26 eV to 1.48 eV and improves the sensing phenomena of pristine T-SnO2 towards C2H5OH by increasing the binding energy from -0.18eV to -0.93eV. The comparative analysis of binding energy shows that Ni improves the binding of C2H5OH by 5.16 times the values for pristine T-SnO2. The doping of Ni into 2D T-SnO2 reduces the band gap through lowering of the conduction band minimum, thereby increasing the electron affinity which increases the sensing performance of T-SnO2. The variation in the electronic properties after and before the exposure of ethanol reinforced to use Ni:SnO2 nano structure for sensing applications. The results indicate that the Ni doped T-SnO2 can be utilized in improved optoelectronic as well as sensor devices in the future.

  8. Polymer-SnO2 composite membranes

    DEFF Research Database (Denmark)

    Nørgaard, Casper Frydendal; Skou, Eivind Morten

    . This work utilizes the latter approach and makes use of particles of tin dioxide (SnO2). Polymer-SnO2 composite membranes were successfully prepared using an ion-exchange method. SnO2 was incorporated into membranes by ion-exchange in solutions of SnCl2 ∙ 2 H2O in methanol, followed by oxidation to SnO2...... in air. The content of SnO2 proved controllable by adjusting the concentration of the ion-exchange solution. The prepared nanocomposite membranes were characterized by powder XRD, 119Sn MAS NMR, electrochemical impedance spectroscopy, water uptake and tensile stress-strain measurements. For Nafion 117...

  9. Solvothermal Synthesis of Zn2SnO4 Nanocrystals and Their Photocatalytic Properties

    Directory of Open Access Journals (Sweden)

    Guang Sun

    2014-01-01

    Full Text Available Crystalline Zn2SnO4 nanoparticles were successfully synthesized via a simple solvothermal route by using Zn(CH3COO2·2H2O and SnCl4·5H2O as source materials, NaOH as mineralizing agent, and water and ethanol as mixed solvents. The used amount of NaOH was found to have an important influence on the formation of Zn2SnO4. When the molar ratio of OH− : Zn2+ : Sn4+ was set in the range from 4 : 2 : 1 to 8 : 2 : 1, Zn2SnO4 nanoparticles with different shape and size were obtained. However, when the molar ratio of OH− : Zn2+ : Sn4+ was set as 10 : 2 : 1, a mixture phase of ZnO and ZnSn(OH6 instead of Zn2SnO4 was obtained. Photodegradation measurements indicated that the Zn2SnO4 nanoparticles own better photocatalytic property to depredate methyl orange than the Zn2SnO4 nanopolyhedrons. The superior photocatalytic properties of Zn2SnO4 nanoparticles may be contributed to their small crystal size and high surface area.

  10. 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.

  11. Ductile fracture mechanism of low-temperature In-48Sn alloy joint under high strain rate loading.

    Science.gov (United States)

    Kim, Jong-Woong; Jung, Seung-Boo

    2012-04-01

    The failure behaviors of In-48Sn solder ball joints under various strain rate loadings were investigated with both experimental and finite element modeling study. The bonding force of In-48Sn solder on an Ni plated Cu pad increased with increasing shear speed, mainly due to the high strain-rate sensitivity of the solder alloy. In contrast to the cases of Sn-based Pb-free solder joints, the transition of the fracture mode from a ductile mode to a brittle mode was not observed in this solder joint system due to the soft nature of the In-48Sn alloy. This result is discussed in terms of the relationship between the strain-rate of the solder alloy, the work-hardening effect and the resulting stress concentration at the interfacial regions.

  12. Effects of interlayer Sn-Sn lone pair interaction on the band gap of bulk and nanosheet SnO

    Science.gov (United States)

    Umezawa, Naoto; Zhou, Wei

    2015-03-01

    Effects of interlayer lone-pair interactions on the electronic structure of SnO are firstly explored by the density-functional theory. Our comprehensive study reveals that the band gap of SnO opens as increase in the interlayer Sn-Sn distance. The effect is rationalized by the character of band edges which consists of bonding and anti-bonding states from interlayer lone pair interactions. The band edges for several nanosheets and strained double-layer SnO are estimated. We conclude that the double-layer SnO is a promising material for visible-light driven photocatalyst for hydrogen evolution. This work is supported by the Japan Science and Technology Agency (JST) Precursory Research for Embryonic Science and Technology (PRESTO) program.

  13. 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.

  14. Investigation of superior electro-optical properties of SnO{sub 2}/SiO{sub 2} nanocomposite over its individual counterpart SnO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Naveen Kumar, P.; Sahaya Selva Mary, J.; Chandrakala, V.; Jothi Jeyarani, W.; Merline Shyla, J., E-mail: jmshyla@gmail.com

    2017-06-01

    A comparative investigation of SnO{sub 2}/SiO{sub 2} nanocomposite with SnO{sub 2} nanoparticles has been conducted in the present study with the intent of learning the probable enhancement of the properties of the nanocomposite over those of the bare nanoparticles which has not been widely reported before. SnO{sub 2} nanoparticles and SnO{sub 2}/SiO{sub 2} nanocomposite have been synthesized via the facile and versatile sol-gel method. The samples were characterized with X-Ray Diffraction (XRD), High Resolution Scanning Electron Microscopy (HRSEM), Brunauer Emmett Teller (BET) studies, Fourier Transform Infra-Red spectroscopy (FT-IR), UV–Visible (UV–Vis) spectroscopy and Field-dependent photo conductivity technique for the evaluation of their crystallite size, structure & morphology, surface, chemical, optical and electrical properties respectively. Scherrer’s equation was used to determine the crystallite size of the as-synthesized samples from the XRD data. The particle size of SnO{sub 2}/SiO{sub 2} nanocomposite as observed through HRSEM was found to be reduced when compared with the bare SnO{sub 2} nanoparticles suggesting a possible increase in the optical band gap of the former which has been further confirmed in the optical studies. The surface area of SnO{sub 2}/SiO{sub 2} nanocomposite revealed a remarkable enrichment by approximately 5 folds in comparison with that of SnO{sub 2} nanoparticles which suggests an enhancement in its corresponding optical and electrical properties. The SnO{sub 2}/SiO{sub 2} nanocomposite recorded appreciated values of field-dependent photo and dark currents with several folds of augmentation thereby qualifying as an efficient photoconducting material. Attributed with an improved surface area and increased photoconducting nature, the SnO{sub 2}/SiO{sub 2} nanocomposite could be presented as an excellent photoanode material for nanomaterials based Dye Sensitized Solar Cells (DSSCs). - Highlights: • SnO{sub 2}/SiO{sub 2

  15. Superparamagnetic behavior of Fe-doped SnO2 nanoparticles

    International Nuclear Information System (INIS)

    Hachisu, M.; Onuma, K.; Kondo, T.; Miike, K.; Miyasaka, T.; Mori, K.; Ichiyanagi, Y.

    2014-01-01

    SnO 2 is an n-type semiconductor with a wide band gap of 3.62 eV, and SnO 2 nanoparticles doped with magnetic ions are expected to realized new diluted magnetic semiconductors (DMSs). Realizing ferromagnetism at room temperature is important for spintronics device applications, and it is interesting that the magnetic properties of these DMS systems can be varied significantly by modifying the preparation methods or conditions. In this study, the magnetic properties of Fe-doped (3% and 5%) SnO 2 nanoparticles, prepared using our novel chemical preparation method and encapsulated in amorphous SiO 2 , were investigated. The particle size (1.8–16.9 nm) and crystal phase were controlled by the annealing temperature. X-ray diffraction confirmed a rutile SnO 2 single-phase structure for samples annealed at 1073–1373 K, and the composition was confirmed using X-ray fluorescence analysis. SQUID magnetometer measurements revealed superparamagnetic behavior of the 5%-Fe-doped sample at room temperature, although SnO 2 is known to be diamagnetic. Magnetization curves at 5 K indicated that the 3%-Fe-doped has a larger magnetization than that of the 5%-Fe-doped sample. We conclude that the magnetization of the 5%-Fe-doped sample decreased at 5 K due to the superexchange interaction between the antiferromagnetic coupling in the nanoparticle system

  16. Superparamagnetic behavior of Fe-doped SnO2 nanoparticles

    Science.gov (United States)

    Hachisu, M.; Onuma, K.; Kondo, T.; Miike, K.; Miyasaka, T.; Mori, K.; Ichiyanagi, Y.

    2014-02-01

    SnO2 is an n-type semiconductor with a wide band gap of 3.62 eV, and SnO2 nanoparticles doped with magnetic ions are expected to realized new diluted magnetic semiconductors (DMSs). Realizing ferromagnetism at room temperature is important for spintronics device applications, and it is interesting that the magnetic properties of these DMS systems can be varied significantly by modifying the preparation methods or conditions. In this study, the magnetic properties of Fe-doped (3% and 5%) SnO2 nanoparticles, prepared using our novel chemical preparation method and encapsulated in amorphous SiO2, were investigated. The particle size (1.8-16.9 nm) and crystal phase were controlled by the annealing temperature. X-ray diffraction confirmed a rutile SnO2 single-phase structure for samples annealed at 1073-1373 K, and the composition was confirmed using X-ray fluorescence analysis. SQUID magnetometer measurements revealed superparamagnetic behavior of the 5%-Fe-doped sample at room temperature, although SnO2 is known to be diamagnetic. Magnetization curves at 5 K indicated that the 3%-Fe-doped has a larger magnetization than that of the 5%-Fe-doped sample. We conclude that the magnetization of the 5%-Fe-doped sample decreased at 5 K due to the superexchange interaction between the antiferromagnetic coupling in the nanoparticle system.

  17. High field-effect mobility at the (Sr,Ba)SnO{sub 3}/BaSnO{sub 3} interface

    Energy Technology Data Exchange (ETDEWEB)

    Fujiwara, Kohei, E-mail: kfujiwara@imr.tohoku.ac.jp; Nishihara, Kazuki; Shiogai, Junichi; Tsukazaki, Atsushi [Institute for Materials Research, Tohoku University, Sendai 980-8577 (Japan)

    2016-08-15

    A perovskite oxide, BaSnO{sub 3}, has been classified as one of transparent conducting materials with high electron mobility, and its application for field-effect transistors has been the focus of recent research. Here we report transistor operation in BaSnO{sub 3}-based heterostructures with atomically smooth surfaces, fabricated on SrTiO{sub 3} substrates by the (Sr,Ba)SnO{sub 3} buffer technique. Indeed, modulation of band profiles at the channel interfaces with the insertion of wide bandgap (Sr,Ba)SnO{sub 3} as a barrier layer results in a significant improvement of field-effect mobility, implying effective carrier doping at the regulated heterointerface. These results provide an important step towards realization of high-performance BaSnO{sub 3}-based field-effect transistors.

  18. Effect of various SnO2 pH on ZnO/SnO2-composite film via immersion technique

    Science.gov (United States)

    Malek, M. F.; Mohamed, R.; Mamat, M. H.; Ismail, A. S.; Yusoff, M. M.; Rusop, M.

    2018-05-01

    ZnO/SnO2-composite film has been synthesized via immersion technique with various pH of SnO2. The pH of SnO2 were varied between 4.5 and 6.5. The optical measurements of the samples were carried out using Varian Cary 5000 UV-Vis spectrophotometer within the range from 350 nm to 800 nm at room temperature in air with a data interval of 1 nm. On the other hand, the optical photoluminescence properties were measured by a photoluminescence spectrometer (PL, model: Horiba Jobin Yvon - 79 DU420A-OE-325) using a He-Cd laser as the excitation source at 325 nm. These highly oriented ZnO/SnO2-composite film are potential for the creation of functional materials, such as the sensors, solar cells and etc.

  19. Preparation of Nafion 117™-SnO2 Composite Membranes using an Ion-Exchange Method

    DEFF Research Database (Denmark)

    Nørgaard, Casper Frydendal; Nielsen, Ulla Gro; Skou, Eivind Morten

    2012-01-01

    Nafion 117™-SnO2 composite membranes were prepared by in-situ particle formation using an ion-exchange method. SnO2 was incorporated into Nafion 117ä membranes by ion-exchange in solutions of SnCl2 ∙2 H2O in methanol, followed by oxidation to SnO2 in air. By adjustment of the concentration of SnCl2...... ∙ 2 H2O used in the ion-exchange step, compositions ranging from 2 to 8 wt% SnO2 with SnO2 homogeneously distributed as nanoparticles were obtained. The prepared nanocomposite membranes were characterized by powder XRD, 119Sn MAS NMR spectroscopy, electrochemical impedance spectroscopy, water uptake...

  20. Nanocrystalline transparent SnO{sub 2}-ZnO films fabricated at lower substrate temperature using a low-cost and simplified spray technique

    Energy Technology Data Exchange (ETDEWEB)

    Ravichandran, K.; Sakthivel, B.; Philominathan, P. [P. G. and Research Department of Physics, AVVM. Sri Pushpam College, Poondi, Thanjavur, Tamilnadu 613503 (India)

    2010-03-15

    Nanocrystalline and transparent conducting SnO{sub 2}- ZnO films were fabricated by employing an inexpensive, simplified spray technique using a perfume atomizer at relatively low substrate temperature (360{+-}5 C) compared with conventional spray method. The structural studies reveal that the SnO{sub 2}-ZnO films are polycrystalline in nature with preferential orientation along the (101) plane. The dislocation density is very low (1.48 x 10{sup 15}lines/m{sup 2}), indicating the good crystallinity of the films. The crystallite size of the films was found to be in the range of 26-34 nm. The optical transmittance in the visible range and the optical band gap are 85% and 3.6 eV respectively. The sheet resistance increases from 8.74 k{omega}/{open_square} to 32.4 k{omega}/{open_square} as the zinc concentration increases from 0 to 40 at.%. The films were found to have desirable figure of merit (1.63 x 10{sup -2} ({omega}/{open_square}){sup -1}), low temperature coefficient of resistance (-1.191/K) and good thermal stability. This simplified spray technique may be considered as a promising alternative to conventional spray for the massive production of economic SnO{sub 2} - ZnO films for solar cells, sensors and opto-electronic applications. (copyright 2010 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  1. Gas Sensing Properties of ZnO-SnO2 Nanostructures.

    Science.gov (United States)

    Chen, Weigen; Li, Qianzhu; Xu, Lingna; Zeng, Wen

    2015-02-01

    One-dimensional (1D) semiconductor metal oxide nanostructures have attracted increasing attention in electrochemistry, optics, magnetic, and gas sensing fields for the good properties. N-type low dimensional semiconducting oxides such as SnO2 and ZnO have been known for the detection of inflammable or toxic gases. In this paper, we fabricated the ZnO-SnO2 and SnO2 nanoparticles by hydrothermal synthesis. Microstructure characterization was performed using X-ray diffraction (XRD) and surface morphologies for both the pristine and doped samples were observed using field emission scanning electron microscope (FESEM), transmission electron microscopy (TEM) and high resolution transmission electron microscopy (HRTEM). Then we made thin film gas sensor to study the gas sensing properties of ZnO-SnO2 and SnO2 gas sensor to H2 and CO. A systematic comparison study reveals an enhanced gas sensing performance for the sensor made of SnO2 and ZnO toward H2 and CO over that of the commonly applied undecorated SnO2 nanoparticles. The improved gas sensing properties are attributed to the size of grains and pronounced electron transfer between the compound nanostructures and the absorbed oxygen species as well as to the heterojunctions of the ZnO nanoparticles to the SnO2 nanoparticles, which provide additional reaction rooms. The results represent an advance of compound nanostructures in further enhancing the functionality of gas sensors, and this facile method could be applicable to many sensing materials, offering a new avenue and direction to detect gases of interest based on composite tin oxide nanoparticles.

  2. Structural Stability and Performance of Noble Metal-Free SnO2-Based Gas Sensors

    Directory of Open Access Journals (Sweden)

    Antonio Tricoli

    2012-05-01

    Full Text Available The structural stability of pure SnO2 nanoparticles and highly sensitive SnO2-SiO2 nanocomposites (0–15 SiO2 wt% has been investigated for conditions relevant to their utilization as chemoresistive gas sensors. Thermal stabilization by SiO2 co-synthesis has been investigated at up to 600 °C determining regimes of crystal size stability as a function of SiO2-content. For operation up to 400 °C, thermally stable crystal sizes of ca. 24 and 11 nm were identified for SnO2 nanoparticles and 1.4 wt% SnO2-SiO2 nanocomposites, respectively. The effect of crystal growth during operation (TO = 320 °C on the sensor response to ethanol has been reported, revealing possible long-term destabilization mechanisms. In particular, crystal growth and sintering-neck formation were discussed with respect to their potential to change the sensor response and calibration. Furthermore, the effect of SiO2 cosynthesis on the cross-sensitivity to humidity of these noble metal-free SnO2-based gas sensors was assessed.

  3. 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.

  4. 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.

  5. 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 ...

  6. Ultra-long Zn{sub 2}SnO{sub 4}-ZnO microwires based gas sensor for hydrogen detection

    Energy Technology Data Exchange (ETDEWEB)

    Fan, Hong [School of Resources and Civil Engineering, Northeastern University, Shenyang 110819 (China); Xu, Shucong [School of Material Science & Engineering, Shandong University, Jinan 250061 (China); Cao, Xianmin; Liu, Daoxi; Yin, Yaoyu; Hao, Haiyong; Wei, Dezhou [School of Resources and Civil Engineering, Northeastern University, Shenyang 110819 (China); Shen, Yanbai, E-mail: shenyanbai@mail.neu.edu.cn [School of Resources and Civil Engineering, Northeastern University, Shenyang 110819 (China)

    2017-04-01

    Highlights: • Ultra-long Zn{sub 2}SnO{sub 4}-ZnO microwires with excellent crystallinity and high yield were obtained. • The maximal length-to-diameter ratio of Zn{sub 2}SnO{sub 4}-ZnO microwires is approximately 1500. • Ultra-long Zn{sub 2}SnO{sub 4}-ZnO microwires show outstanding H{sub 2} sensing properties. - Abstract: Ultra-long Zn{sub 2}SnO{sub 4}-ZnO microwires were synthesized by thermal evaporation of the mixture of SnO{sub 2}, ZnO and C powders. Microstructural characterization by means of X-ray diffraction, scanning electron microscopy and energy dispersive X-ray spectroscopy showed that Zn{sub 2}SnO{sub 4}-ZnO microwires with excellent crystallinity were 2.8–3.2 μm in diameter and 4.0–4.2 mm in length. The maximal length-to-diameter ratio of Zn{sub 2}SnO{sub 4}-ZnO microwires is approximately 1500. H{sub 2} sensing properties showed that Zn{sub 2}SnO{sub 4}-ZnO microwires exhibited not only excellent reversibility to H{sub 2}, but also a good linear relationship between the sensor response and H{sub 2} concentration. The response time and recovery time decreased as the operating temperature increased. The highest sensor response of 9.6 to 1000 ppm H{sub 2} was achieved at an operating temperature of 300 °C. The electron depletion theory was used for explaining H{sub 2} sensing mechanism by the chemical adsorption and reaction of H{sub 2} molecules on the surface of Zn{sub 2}SnO{sub 4}-ZnO microwires.

  7. Sintering of undoped SnO2 Sinterização de SnO2 não dopado

    Directory of Open Access Journals (Sweden)

    E. R. Leite

    2003-04-01

    Full Text Available Pure SnO2 sintering was studied by constant heating rate and isothermal sintering. The constant heating rate study showed no macroscopic shrinkage during the sintering process up to 1500 ºC. Pore size distribution measurements, using gas desorption, and grain size and crystallite size measurements of isothermally sintered samples showed no formation of non-densifying microstructures during the sintering process. These results are a strong indication that densification was prevented by thermodynamic factors, mainly the high ratio of gammaGB/gSV. An explanation, based on the nature of covalent bonding and the balance between attractive and repulsive forces, was proposed to explain the high gammaGB/gammaSV ratio in SnO2.A sinterização de SnO2 puro foi estudado por taxa constante de aquecimento e por sinterização isotérmica. O estudo de taxa constante de aquecimento mostrou que não ocorre retração macroscópica durante o processo de sinterização até temperaturas de 1500 ºC. Medidas de distribuição de tamanho de poros, usando adsorção de gás, tamanho de grão e tamanho de cristalito para amostras sinterizadas isotermicamente mostrou a não formação de uma microestrutura não-densificante durante o processo de sinterização. Estes resultados são um forte indicativo que a densificação foi inibida por fatores termodinâmicos, principalmente o alto valor da razão de gamaGB/gSV. Uma explicação, baseada na natureza covalente da ligação química e no balanço entre forças atrativas e repulsivas, é apresentada para explicar o alto valor da razão gamaGB/gamaSV no SnO2.

  8. Carbon encapsulated ultrasmall SnO2 nanoparticles anchoring on graphene/TiO2 nanoscrolls for lithium storage

    International Nuclear Information System (INIS)

    Li, Xinlu; Zhang, Yonglai; Li, Tongtao; Zhong, Qineng; Li, Hongyi; Huang, Jiamu

    2014-01-01

    Highlights: • Highly-dispersive ultrasmall SnO 2 nanoparticles (4∼8 nm) are anchored on the substrate of graphene/TiO 2 nanoscrolls. • The encapsulated glucose-derived carbon layer effectively immobilizes SnO 2 nanoparticles. • The enhanced cycling performance is owing to the synergetic effects between the multicomposites. - Abstract: Amorphous carbon is coated on the surface of ultrasmall SnO 2 nanoparticles which are anchored on graphene/TiO 2 nanoscrolls via hydrothermal treatment, followed by annealing process. Transmission electron microscope images show that ultrasmall SnO 2 nanoparticles are anchored on graphene/TiO 2 nanoscrolls and further immobilized by the outermost amorphous carbon layer. The carbon encapsulated SnO 2 @graphene/TiO 2 nanocomposites deliver high reversible capacities around 1131, 793, 621 and 476 mAh g −1 at the current densities of 100, 250, 500, and 1000 mA g −1 , respectively. It is found that SnO 2 nanoparticles play a dominant role in the contributions of reversible capacity according to the cyclic voltammetry curves, voltage-capacity curves and dQ/dV vs. potential curves. The substrate of graphene/TiO 2 nanoscrolls provides sufficient transport channels for lithium ions and high electron conductivity. While the outermost amorphous carbon layer prevents the peeling of SnO 2 nanoparticles from the substrate, therefore making them desirable alternative anode materials for lithium ion batteries

  9. Theoretical band structure of the superconducting antiperovskite oxide Sr3-xSnO

    Science.gov (United States)

    Ikeda, Atsutoshi; Fukumoto, Toshiyuki; Oudah, Mohamed; Hausmann, Jan Niklas; Yonezawa, Shingo; Kobayashi, Shingo; Sato, Masatoshi; Tassel, Cédric; Takeiri, Fumitaka; Takatsu, Hiroshi; Kageyama, Hiroshi; Maeno, Yoshiteru

    2018-05-01

    In order to investigate the position of the strontium deficiency in superconductive Sr3-xSnO, we synthesized and measured X-ray-diffraction patterns of Sr3-xSnO (x ∼ 0.5). Because no clear peaks originating from superstructures were observed, strontium deficiency is most likely to be randomly distributed. We also performed first-principles band-structure calculations on Sr3-xSnO (x = 0, 0.5) using two methods: full-potential linearized-augmented plane-wave plus local orbitals method and the Korringa-Kohn-Rostoker Green function method combined with the coherent potential approximation. We revealed that the Fermi energy of Sr3-xSnO in case of x ∼ 0.5 is about 0.8 eV below the original Fermi energy of the stoichiometric Sr3SnO, where the mixing of the valence p and conduction d orbitals are considered to be small.

  10. Superparamagnetic behavior of Fe-doped SnO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Hachisu, M.; Onuma, K.; Kondo, T.; Miike, K.; Miyasaka, T.; Mori, K.; Ichiyanagi, Y. [Department of Physics, Graduate School of Engineering, Yokohama National University, 79-5 Tokiwadai, Hodogaya, Yokohama, Kanagawa 240-8501 (Japan)

    2014-02-20

    SnO{sub 2} is an n-type semiconductor with a wide band gap of 3.62 eV, and SnO{sub 2} nanoparticles doped with magnetic ions are expected to realized new diluted magnetic semiconductors (DMSs). Realizing ferromagnetism at room temperature is important for spintronics device applications, and it is interesting that the magnetic properties of these DMS systems can be varied significantly by modifying the preparation methods or conditions. In this study, the magnetic properties of Fe-doped (3% and 5%) SnO{sub 2} nanoparticles, prepared using our novel chemical preparation method and encapsulated in amorphous SiO{sub 2}, were investigated. The particle size (1.8–16.9 nm) and crystal phase were controlled by the annealing temperature. X-ray diffraction confirmed a rutile SnO{sub 2} single-phase structure for samples annealed at 1073–1373 K, and the composition was confirmed using X-ray fluorescence analysis. SQUID magnetometer measurements revealed superparamagnetic behavior of the 5%-Fe-doped sample at room temperature, although SnO{sub 2} is known to be diamagnetic. Magnetization curves at 5 K indicated that the 3%-Fe-doped has a larger magnetization than that of the 5%-Fe-doped sample. We conclude that the magnetization of the 5%-Fe-doped sample decreased at 5 K due to the superexchange interaction between the antiferromagnetic coupling in the nanoparticle system.

  11. Preparation of ZnO/SnO2 Composite Nanometer Photocatalyst and Photocatalytic Treatment of Marine Diesel Pollution

    Science.gov (United States)

    Zhang, J.; Yu, X. C.; Nie, Z. W.; Guo, M. C.; Liu, J. H.; Wang, L. P.

    2017-12-01

    The ZnO/SnO2 composite nanophotocatalyst studied in this paper was prepared by a chemical precipitation method, which were characterized by XRD and SEM. The results show that the prepared samples were rutile SnO2 particles and the average grain size is 8.41 nm. In this paper, the factors for the degradation efficiency of marine diesel oil degraded by ZnO/SnO2 composite nanophotocatalyst are the catalysts’ doping ratio, the initial concentration of oil, the pH value of seawater, the dosage of catalyst and the dosage of hydrogen peroxide. The results show that the ZnO/SnO2 composite nanophotocatalyst can effectively degrade seawater diesel oil under UV light. When the doping ratio of ZnO and SnO2 is 0.35, the reaction time is 2.5 hours, the pH value of seawater with oil is 7, The concentration of diesel oil is 0.1g/L, the dosage of catalyst is 0.3g/L and the dosage of hydrogen peroxide is 0.1 g/L, the highest degradation rate is 91.54%.

  12. In Situ High-Resolution Transmission Electron Microscopy (TEM) Observation of Sn Nanoparticles on SnO2 Nanotubes Under Lithiation.

    Science.gov (United States)

    Cheong, Jun Young; Chang, Joon Ha; Kim, Sung Joo; Kim, Chanhoon; Seo, Hyeon Kook; Shin, Jae Won; Yuk, Jong Min; Lee, Jeong Yong; Kim, Il-Doo

    2017-12-01

    We trace Sn nanoparticles (NPs) produced from SnO2 nanotubes (NTs) during lithiation initialized by high energy e-beam irradiation. The growth dynamics of Sn NPs is visualized in liquid electrolytes by graphene liquid cell transmission electron microscopy. The observation reveals that Sn NPs grow on the surface of SnO2 NTs via coalescence and the final shape of agglomerated NPs is governed by surface energy of the Sn NPs and the interfacial energy between Sn NPs and SnO2 NTs. Our result will likely benefit more rational material design of the ideal interface for facile ion insertion.

  13. 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.

  14. Microwave dielectric properties of (Ca0.8Sr0.2)(SnxTi1−x)O3 ceramics

    International Nuclear Information System (INIS)

    Hsu, Cheng-Hsing; Chang, Chia-Hao

    2013-01-01

    Highlights: ► New microwave dielectric properties of (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 ceramics were investigated. ► A single-phase solid solution containing orthorhombic Pbnm with different Sn contents was formed. ► A significant improvement of Q × f value and τ f were achieved by (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 system. ► Second phases were formed and affected the dielectric properties of (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 system. ► Low cost and suitable τ f value of (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 demonstrate a good potential for use in microwave device. -- Abstract: In this paper, we study the behavior of the B-site behavior with the incorporation of Sn 4+ ion in (Ca 0.8 Sr 0.2 )TiO 3 ceramics. An excess of Sn 4+ resulted in the formation of a secondary phase of CaSnO 3 and SrSnO 3 affecting the microwave dielectric properties of the (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 ceramics. The dielectric properties of the (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 ceramics were improved because of the solid solution of Sn 4+ substitution in the B-site. The temperature coefficient of resonant frequency (τ f ) of the (Ca 0.8 Sr 0.2 )(Sn x Ti 1−x )O 3 ceramics also improved with increasing Sn content

  15. Thermoelectric Properties in the TiO2/SnO2 System

    Science.gov (United States)

    Dynys, F.; Sayir, A.; Sehirlioglu, A.; Berger, M.

    2009-01-01

    Nanotechnology has provided a new interest in thermoelectric technology. A thermodynamically driven process is one approach in achieving nanostructures in bulk materials. TiO2/SnO2 system exhibits a large spinodal region with exceptional stable phase separated microstructures up to 1400 C. Fabricated TiO2/SnO2 nanocomposites exhibit n-type behavior with Seebeck coefficients greater than -300 .V/K. Composites exhibit good thermal conductance in the range of 7 to 1 W/mK. Dopant additions have not achieved high electrical conductivity (<1000 S/m). Formation of oxygen deficient composites, TixSn1-xO2-y, can change the electrical conductivity by four orders of magnitude. Achieving higher thermoelectric ZT by oxygen deficiency is being explored. Seebeck coeffcient, thermal conductivity, electrical conductance and microstructure will be discussed in relation to composition and doping.

  16. Study of interfacial reactions in Sn-3.5Ag-3.0Bi and Sn-8.0Zn-3.0Bi sandwich structure solder joint with Ni(P)/Cu metallization on Cu substrate

    International Nuclear Information System (INIS)

    Sun, Peng; Andersson, Cristina; Wei, Xicheng; Cheng, Zhaonian; Shangguan, Dongkai; Liu, Johan

    2007-01-01

    In this paper, the coupling effect in Sn-3.5Ag-3.0Bi and Sn-8.0Zn-3.0Bi solder joint with sandwich structure by long time reflow soldering was studied. It was found that the interfacial compound at the Cu substrate was binary Cu-Sn compound in Sn-Ag-Bi solder joint and Cu 5 Zn 8 phase in Sn-Zn-Bi solder joint. The thickness of the Cu-Zn compound layer formed at the Cu substrate was greater than or equal to that of Cu-Sn compound layer, although the reflow soldering temperature of Sn-Zn-Bi (240 o C) was lower than that of Sn-Ag-Bi (250 o C). The stable Cu-Zn compound was the absolute preferential phase in the interfacial layer between Sn-Zn-Bi and the Cu substrate. The ternary (Cu, Ni) 6 Sn 5 compound was formed at the Sn-Ag-Bi/Ni(P)-Cu metallization interface, and a complex alloy Sn-Ni-Cu-Zn was formed at the Sn-Zn-Bi/Ni(P)-Cu metallization interface. It was noted that Cu atoms could diffuse from the Cu substrate through the solder matrix to the Ni(P)-Cu metallization within 1 min reflow soldering time for both solder systems, indicating that just 30 s was long enough for Cu to go through 250 μm diffusion length in the Sn-Ag-Bi solder joint at 250 o C. The coupling effect between Ni(P)/Cu metallization and Cu substrate was confirmed as the type of IMCs at Ni(P) layer had been changed from Ni-Sn system to Cu-Sn system apparently by the diffusion effect of Cu atoms. The (Cu, Ni) 6 Sn 5 layer at the Ni(P)/Cu metallization grew significantly and its thickness was even greater than that of the Cu-Sn compound on the opposite side, however the growth of the complex alloy including Sn, Ni, Cu and Zn on the Ni(P)/Cu metallization was suppressed

  17. 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

  18. High-temperature entropy of anionic model for the phase transition in SnCl2.2H2O

    International Nuclear Information System (INIS)

    Freitas, L.C. de; Salinas, S.R.

    1975-01-01

    The basic model of the phase transition in the hydrogen-bonded layered crystal SnCl 2 .2H 2 O to account for the presence of ionic defects is modified. It is easy to obtain a series expansion for the high-temperature entropy of the ionic model in terms of closed subgraphs, with vertices of degree two, of the original three-coordinated 4-8 lattice. High-temperature entropy of the ionic model is shown to be identical to the residual entropy of a simple antiferromagnetic Ising model in a 3-4-8 lattice. This latter model can be solved exact by a set of transformations which lead to a well studied Ising model in a Union Jack lattice [pt

  19. Ethanol electrooxidation on novel carbon supported Pt/SnO{sub x}/C catalysts with varied Pt:Sn ratio

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, L. [Institute of Surface Chemistry and Catalysis, Ulm University, D-89069 Ulm (Germany); Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023 Dalian (China); Colmenares, L.; Jusys, Z. [Institute of Surface Chemistry and Catalysis, Ulm University, D-89069 Ulm (Germany); Sun, G.Q. [Dalian Institute of Chemical Physics, Chinese Academy of Sciences, 116023 Dalian (China)], E-mail: gqsun@dicp.ac.cn; Behm, R.J. [Institute of Surface Chemistry and Catalysis, Ulm University, D-89069 Ulm (Germany)], E-mail: juergen.behm@uni-ulm.de

    2007-12-01

    Novel carbon supported Pt/SnO{sub x}/C catalysts with Pt:Sn atomic ratios of 5:5, 6:4, 7:3 and 8:2 were prepared by a modified polyol method and characterized with respect to their structural properties (X-ray diffraction (XRD) and transmission electron microscopy (TEM)), chemical composition (XPS), their electrochemical properties (base voltammetry, CO{sub ad} stripping) and their electrocatalytic activity and selectivity for ethanol oxidation (ethanol oxidation reaction (EOR)). The data show that the Pt/SnO{sub x}/C catalysts are composed of Pt and tin oxide nanoparticles with an average Pt particle diameter of about 2 nm. The steady-state activity of the Pt/SnO{sub x}/C catalysts towards the EOR decreases with tin content at room temperature, but increases at 80 deg. C. On all Pt/SnO{sub x}/C catalysts, acetic acid and acetaldehyde represent dominant products, CO{sub 2} formation contributes 1-3% for both potentiostatic and potentiodynamic reaction conditions. With increasing potential, the acetaldehyde yield decreases and the acetic acid yield increases. The apparent activation energies of the EOR increase with tin content (19-29 kJ mol{sup -1}), but are lower than on Pt/C (32 kJ mol{sup -1}). The somewhat better performance of the Pt/SnO{sub x}/C catalysts compared to alloyed PtSn{sub x}/C catalysts is attributed to the presence of both sufficiently large Pt ensembles for ethanol dehydrogenation and C-C bond splitting and of tin oxide for OH generation. Fuel cell measurements performed for comparison largely confirm the results obtained in model studies.

  20. Study on sensing mechanism of CuO-SnO2 gas sensors

    International Nuclear Information System (INIS)

    Zhou Xiaohua; Cao Quanxi; Huang Hui; Yang Peng; Hu Ying

    2003-01-01

    The preparations of SnO 2 and CuO powders and the manufacture of CuO-SnO 2 gas sensors are described in some details. The CuO content was chosen as 1.5 mol.% (sample 1), 4.4 mol.% (sample 2), 8.4 mol.% (sample 3) and 12.5 mol.% (sample 4), respectively. The resistance of all samples in air and their sensitive properties to H 2 S, alcohol vapor, C 4 H 10 and CH 2 were measured in the temperature range 20-300 deg. C, respectively. The results show that the resistance of all samples decreases exponentially with increasing temperature, when the temperature is >31 deg. C and it increases with an increase in CuO content at a given temperature. Sample 3 exhibits the best sensitive property in the case of the same H 2 S-air mixture concentration and excellent selectivity. The sensitive mechanisms of these samples to different gases are discussed in details

  1. The effects of sulfur intercalation on the optical properties of artificial 'hackmanite', Na8[Al6Si6O24]Cl1.8S0.1; 'sulfosodalite', Na8[Al6Si6O24]S; and natural tugtupite, Na8

    DEFF Research Database (Denmark)

    Warner, Terence Edwin; Hutzen Andersen, Jan

    2012-01-01

    .8S0.1 destroys the tenebrescence and induces a permanently pale blue and, at higher temperature, a pale green coloration. The effect on Na8[Al6Si6O24]S induced similar colorations but of a deeper hue. Annealing tugtupite, Na8[Be2Al2Si8O24](Cl,S)2-x under a sulfur atmosphere over the range 600-700 °C......, destroyed the tenebrescence and resulted in a colourless tugtupite; but did not effect the photoluminescence. This suggests that the chemical species responsible for the tenebrescence in tugtupite is unlikely to be the same as that for the luminescence....

  2. 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)

  3. Ab initio study of native defects in SnO under strain

    KAUST Repository

    Bianchi Granato, Danilo

    2014-04-01

    Tin monoxide (SnO) has promising properties to be applied as a p-type semiconductor in transparent electronics. To this end, it is necessary to understand the behaviour of defects in order to control them. We use density functional theory to study native defects of SnO under tensile and compressive strain. We show that Sn vacancies are less stable under tension and more stable under compression, irrespectively of the charge state. In contrast, O vacancies behave differently for different charge states. It turns out that the most stable defect under compression is the +1 charged O vacancy in an Sn-rich environment and the charge neutral O interstitial in an O-rich environment. Therefore, compression can be used to transform SnO from a p-type into either an n-type or an undoped semiconductor. Copyright © EPLA, 2014.

  4. 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.

  5. Synthesis, characterization and photocatalytic activity of ZnO-SnO2 nanocomposites

    International Nuclear Information System (INIS)

    Hamrouni, Abdessalem; Lachheb, Hinda; Houas, Ammar

    2013-01-01

    Highlights: • ZnO-SnO 2 photocatalysts were prepared successfully by the coprecipitation method. • The best conditions found are: calcination at 600 °C/2 h; molar ratio Zn/Sn = 1/0.05. • The lower tin content in the samples led to the higher photocatalytic activity. • Zn-Sn 0.05 photoactivity under solar light was better than visible lamps light. -- Abstract: Nanocomposites of coupled ZnO-SnO 2 photocatalysts were synthesized by the coprecipitation method and were characterized by X-ray diffraction, UV–vis diffuse reflectance spectroscopy, surface area analyzer and scanning electron microscopy. Their photocatalytic activity was investigated under UV, visible and solar light and evaluated using methylene blue (MB) as a model pollutant. The performance of the coupled ZnO-SnO 2 photocatalysts was found to be related to the Zn/Sn molar ratio and to the calcination conditions. The photocatalyst with a Zn/Sn molar ratio of 1:0.05 calcined at 600 °C for 2 h showed the maximum degradation rate of MB under different lights used. Its photocatalytic activity was found to be about two times that of ZnO and about 10 times that of SnO 2 which can be explained by the heterojunction effect. Charge separation mechanism has been studied

  6. SnO{sub 2}{sup *}CoO ceramic obtained by microwave sintering; Ceramicas de SnO{sub 2} {sup *}CoO obtidas por sinterizacao microondas

    Energy Technology Data Exchange (ETDEWEB)

    Bordignon, M.A.N; Moura, F.; Zaghete, M.A.; Varela, J.A.; Perazolli, L. [Universidade Estadual Paulista (UNESP), Araraquara, SP (Brazil). Chemistry Institute. Dept. de Biochemistry and Technological Chemistryl

    2009-07-01

    This work consists in the sintering study of CoO doped SnO{sub 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{sub 2} with low resistivity to obtain electro-ceramic devices. (author)

  7. Hierarchical Graphene-Encapsulated Hollow SnO2@SnS2 Nanostructures with Enhanced Lithium Storage Capability.

    Science.gov (United States)

    Xu, Wangwang; Xie, Zhiqiang; Cui, Xiaodan; Zhao, Kangning; Zhang, Lei; Dietrich, Grant; Dooley, Kerry M; Wang, Ying

    2015-10-14

    Complex hierarchical structures have received tremendous attention due to their superior properties over their constitute components. In this study, hierarchical graphene-encapsulated hollow SnO2@SnS2 nanostructures are successfully prepared by in situ sulfuration on the backbones of hollow SnO2 spheres via a simple hydrothermal method followed by a solvothermal surface modification. The as-prepared hierarchical SnO2@SnS2@rGO nanocomposite can be used as anode material in lithium ion batteries, exhibiting excellent cyclability with a capacity of 583 mAh/g after 100 electrochemical cycles at a specific current of 200 mA/g. This material shows a very low capacity fading of only 0.273% per cycle from the second to the 100th cycle, lower than the capacity degradation of bare SnO2 hollow spheres (0.830%) and single SnS2 nanosheets (0.393%). Even after being cycled at a range of specific currents varied from 100 mA/g to 2000 mA/g, hierarchical SnO2@SnS2@rGO nanocomposites maintain a reversible capacity of 664 mAh/g, which is much higher than single SnS2 nanosheets (374 mAh/g) and bare SnO2 hollow spheres (177 mAh/g). Such significantly improved electrochemical performance can be attributed to the unique hierarchical hollow structure, which not only effectively alleviates the stress resulting from the lithiation/delithiation process and maintaining structural stability during cycling but also reduces aggregation and facilitates ion transport. This work thus demonstrates the great potential of hierarchical SnO2@SnS2@rGO nanocomposites for applications as a high-performance anode material in next-generation lithium ion battery technology.

  8. Hyperfine magnetic fields at 57Fe and 119Sn nuclei in the Fe48Rh52 alloy under pressure

    International Nuclear Information System (INIS)

    Nikolaev, I.N.; Potapov, V.N.; Bezotosnyj, I.Yu.; Mar'in, V.P.

    1978-01-01

    The pressure dependences of the hyperfine magnetic fields, H, and isomer shifts epsilon at the 57 Fe and 119 Sn nuclei in the Fe 48 Rh 52 alloy with an admixture of approximately 1 at. % Sn are measured by the Moessbauer effect technique. Under pressure epsilon decreases this signifying an increase (for 57 Fe) or decrease (for 119 Sn) of the s-electron density at the nuclei. In the ferromagnetic (FM) state at 398 K, ΔH/HΔp=(-2.8+-0.2)x10 -3 kbar -1 for 57 Fe and ΔH/HΔp=(-4.8+-0.8)x10 -3 kbar -1 for 119 Sn. In the antiferromagnetic (AFM) state at 78 K, ΔH/HΔp approximately 0 for 57 Fe and ΔH/HΔp=(-6.2+-1.0)x10 -3 kbar -1 for 119 Sn. The results for 57 Fe in the FM state can be ascribed to the strong dependence of the alloy matrix magnetization on the pressure and in the AFM state to the absence of local polarization of s-similar collectivized electrons and to the independence of the magnetic moments of the Fe ions of pressure. The causes of the different effect of pressure on the magnetic moments of Fe ions in the FM and AFM states are discussed. The results for 119 Sn in the FM and AFM states of the alloy are in agreement with the model of hyperfine fields at impurity Sn atoms in the magnetic matrices proposed earlier. The radial dependence of the hyperfine field at the 119 Sn nuclei in the AFM state is estimated and it is found that H(r) is stronger than r -9

  9. Tsygankoite, Mn8Tl8Hg2(Sb21Pb2TlΣ24S48, a New Sulfosalt from the Vorontsovskoe Gold Deposit, Northern Urals, Russia

    Directory of Open Access Journals (Sweden)

    Anatoly V. Kasatkin

    2018-05-01

    Full Text Available Tsygankoite, ideally Mn8Tl8Hg2(Sb21Pb2TlΣ24S48, is a new sulfosalt discovered at the Vorontsovskoe gold deposit, Northern Urals, Russia. It occurs as lath-like elongated crystals up to 0.2 mm embedded in calcite–dolomite–clinochlore matrix. The associated minerals also include aktashite, alabandite, arsenopyrite, barite, cinnabar, fluorapatite, orpiment, pyrite, realgar, routhierite, sphalerite, tilasite, and titanite. The new mineral is non-fluorescent, black, and opaque with a metallic lustre and black streak. It is brittle with an uneven fracture and no obvious parting and cleavage. Its Vickers hardness (VHN10 is 144 kg/mm2 (range 131–167 kg/mm2 and its calculated density is 5.450 g cm. In reflected light, tsygankoite is white; between crossed polars it is dark grey to black. It is strongly anisotropic: rotation tints vary from light grey to dark grey to black. Pleochroism and internal reflections are not observed. The chemical composition of tsygankoite (wt %, electron-microprobe data is: Mn 6.29, Hg 5.42, Tl 26.05, Pb 5.84, As 3.39, Sb 30.89, S 21.87, total 99.75. The empirical formula, calculated on the basis of 90 atoms pfu, is: Mn8.06Tl8.00Hg1.90(Sb17.87As3.19Pb1.99Tl0.97Σ24.02S48.03. Tsygankoite is monoclinic, space group C2/m, a = 21.362(4 Å, b = 3.8579(10 Å, c = 27.135(4 Å, β = 106.944(14°, V = 2139.19(17 Å3 and Z = 1. The five strongest diffraction peaks from X-ray powder pattern (listed as (d,Å(I(hkl are: 3.587(100(112, 3.353(70(−114, 3.204(88(405, 2.841(72(−513, and 2.786(99(−514. The crystal structure of tsygankoite was refined from single-crystal X-ray diffraction data to R = 0.0607 and consists of an alternation of two thick layer-like arrays, one based on PbS-archetype and the second on SnS-archetype. Tsygankoite has been approved by the IMA-CNMNC under the number 2017-088. It is named for Mikhail V. Tsyganko, a mineral collector from Severouralsk, Northern Urals, Russia, who collected the samples where the

  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. Li2SnO3 derived secondary Li-Sn alloy electrode for lithium-ion batteries

    International Nuclear Information System (INIS)

    Zhang, D.W.; Zhang, S.Q.; Jin, Y.; Yi, T.H.; Xie, S.; Chen, C.H.

    2006-01-01

    As a possible high-capacity Li-ion battery anode material, Li 2 SnO 3 was prepared via a solid-state reaction route and a sol-gel route, separately. Its electrochemical performance was tested in coin-type cells with metallic Li as the counter electrode. The results show that the sol-gel derived Li 2 SnO 3 has uniform nano-sized particles (200-300 nm) and can deliver a better reversible capacity (380 mAh/g after 50 cycles in the voltage window of 0-1 V) than that from the solid-state reaction route. The characterizations by means of galvanostatic cycling, cyclic voltammetry and ex situ X-ray diffraction indicate that the electrochemical process of the Li 2 SnO 3 lithiation proceeds with an initial structural reduction of the composite oxide into Sn-metal and Li 2 O followed by a reversible Li-Sn alloy formation in the Li 2 O matrix. Due to the buffer role of the Li 2 O matrix, the reversibility of the secondary Li-Sn alloy electrode is largely secured

  12. Synthesis, characterization and electromagnetic properties of SnO-coated FeNi alloy nanocapsules

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mingling; Li, Honglin; Xu, Taotao; Nie, Yu, E-mail: lml771212@163.com [College of Chemistry and Material Engineering, Chaohu University (China)

    2016-11-15

    SnO-coated FeNi alloy nanocapsules have been synthesized by an arc-discharge method. High resolution transmission electron microscopy and x-ray photoelectron spectroscopy analysis show that the nanocapsules have a shell/core structure with FeNi alloy nanoparticles as the core and amorphous SnO as the shell. Dielectric relaxation of SnO shell and the interfacial relaxation between SnO shell and FeNi core lead to the dual nonlinear dielectric resonance. The natural resonance in the SnO coated FeNi nanocapsules shifts to 14.0 GHz. Reflection loss (RL) reaches -46.1 dB at 14.8 GHz for a matching thickness of 1.95 mm, while it exceeds-20 dB over the 13.6 -16.7 GHz range and it exceeds -10 dB in the whole Ku-band (12.4-18 GHz). In addition, the optimal RL values at 5.0-7.6 GHz with the absorbing thickness of 3.4-5.0 mm just exhibit a slight fluctuation. (author)

  13. 3-Amino-1,2,4-triazolium ion in [24(3at)]Cl and [24(3at)]2SnCl6·H2O. Comparative X-ray, vibrational and theoretical studies

    Science.gov (United States)

    Daszkiewicz, Marek; Marchewka, Mariusz K.

    2012-09-01

    Crystal structures of 3-amino-1,2,4-triazolium chloride and bis(3-amino-1,2,4-triazolium) hexachloridostannate monohydrate were determined by means of X-ray single crystal diffraction. The route of protonation of organic molecule and tautomer equilibrium constants for the cationic forms were calculated using B3LYP/6-31G* method. The most stable protonated species is 2,4-H2-3-amino-1,2,4-triazolium ion, 24(3at)+. Very good agreement between theoretical and experimental frequencies was achieved due to very weak interactions existing in studied compounds. Significantly weaker intermolecular interactions are found in [24(3at)]2SnCl6·H2O than in [24(3at)]Cl. The differences in strength of interactions are manifested in red and blue shifts for stretching and bending motions, respectively. PED calculations show that for 24(3at)+ ion the stretching type of motion of two Nringsbnd H bonds is independent, whereas bending is coupled.

  14. Polyaniline assisted by TiO2:SnO2 nanoparticles as a hydrogen gas sensor at environmental conditions

    Science.gov (United States)

    Nasirian, Shahruz; Milani Moghaddam, Hossain

    2015-02-01

    In the present research, polyaniline assisted by TiO2:SnO2 nanoparticles was synthesized and deposited onto an epoxy glass substrate with Cu-interdigited electrodes for gas sensing application. To examine the efficiency of the polyaniline/TiO2:SnO2 nanocomposite (PTS) as a hydrogen (H2) gas sensor, its nature, stability, response, recovery/response time have been studied with a special focus on its ability to work at environmental conditions. H2 gas sensing results demonstrated that a PTS sensor with 20 and 10 wt% of anatase-TiO2 and SnO2 nanoparticles, respectively, has the best response time (75 s) with a recovery time of 117 s at environmental conditions. The highest (lowest) response (recovery time) was 6.18 (46 s) in PTS sensor with 30 and 15 wt% of anatase- (rutile-)TiO2 and SnO2 nanoparticles, respectively, at 0.8 vol.% H2 gas. Further, the H2 gas sensing mechanism of PTS sensor has also been studied.

  15. 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.

  16. MeV ion irradiation induced evolution of morphological, structural and optical properties of nanostructured SnO2 thin films

    International Nuclear Information System (INIS)

    Mohapatra, Satyabrata; Bhardwaj, Neha; Pandey, Akhilesh

    2015-01-01

    Nanostructured SnO 2 thin films were prepared by carbothermal evaporation method. Morphological, structural and optical properties of the SnO 2 thin films, before and after 8 MeV Si ion irradiation to fluences varying from 1 × 10 13 to 1 × 10 15 ions cm −2 , were well characterized using atomic force microscopy (AFM), field emission scanning electron microscopy (FESEM), x-ray diffraction (XRD), Raman spectroscopy and photoluminescence spectroscopy (PL). XRD studies revealed the presence of SnO 2 and Sn nanoparticles in the as-deposited samples. AFM and FESEM studies on the irradiated samples revealed formation of nanoring-like structures, at a fluence of 1 × 10 15 ions cm −2 , with a central hole and circular rim consisting of nearly monodisperse SnO 2 nanoparticles. PL studies revealed strong enhancement in UV emissions upon 8 MeV Si ion irradiation. A growth mechanism underlying the formation of SnO 2 nanorings involving self-assembly of SnO 2 nanoparticles around nanoholes is tentatively proposed. (paper)

  17. TDPAC study of Cd-doped SnO

    Energy Technology Data Exchange (ETDEWEB)

    Munoz, E. L., E-mail: munoz@fisica.unlp.edu.ar [Universidad Nacional de La Plata, Departamento de Fisica-IFLP (CCT-La Plata, CONICET-UNLP), Facultad de Ciencias Exactas (Argentina); Carbonari, A. W. [Instituto de Pesquisas Energeticas y Nucleares-IPEN-CNEN/SP (Brazil); Errico, L. A. [Universidad Nacional de La Plata, Departamento de Fisica-IFLP (CCT-La Plata, CONICET-UNLP), Facultad de Ciencias Exactas (Argentina); Bibiloni, A. G. [Universidad Nacional de La Plata, Departamento de Fisica, Facultad de Ciencias Exactas (Argentina); Petrilli, H. M. [Universidade de Sao Paulo, Instituto de Fisica (Brazil); Renteria, M. [Universidad Nacional de La Plata, Departamento de Fisica-IFLP (CCT-La Plata, CONICET-UNLP), Facultad de Ciencias Exactas (Argentina)

    2007-07-15

    The combination of hyperfine techniques and ab initio calculations has been shown to be a powerful tool to unravel structural and electronic characterizations of impurities in solids. A recent example has been the study of Cd-doped SnO, where ab initio calculations questioned previous TDPAC assignments of the electric-field gradient (EFG) in {sup 111}In-implanted Sn-O thin films. Here we present new TDPAC experiments at {sup 111}In-diffused polycrystalline SnO. A reversible temperature dependence of the EFG was observed in the range 295-900 K. The TDPAC results were compared with theoretical calculations performed with the full-potential linearized augmented plane wave (FP-LAPW) method, in the framework of the density functional theory. Through the comparison with the theoretical results, we infer that different electronic surroundings around Cd impurities can coexist in the SnO sample.

  18. TDPAC study of Cd-doped SnO

    International Nuclear Information System (INIS)

    Munoz, E. L.; Carbonari, A. W.; Errico, L. A.; Bibiloni, A. G.; Petrilli, H. M.; Renteria, M.

    2007-01-01

    The combination of hyperfine techniques and ab initio calculations has been shown to be a powerful tool to unravel structural and electronic characterizations of impurities in solids. A recent example has been the study of Cd-doped SnO, where ab initio calculations questioned previous TDPAC assignments of the electric-field gradient (EFG) in 111 In-implanted Sn-O thin films. Here we present new TDPAC experiments at 111 In-diffused polycrystalline SnO. A reversible temperature dependence of the EFG was observed in the range 295-900 K. The TDPAC results were compared with theoretical calculations performed with the full-potential linearized augmented plane wave (FP-LAPW) method, in the framework of the density functional theory. Through the comparison with the theoretical results, we infer that different electronic surroundings around Cd impurities can coexist in the SnO sample.

  19. Moessbauer spectroscopy study of the synthesis of SnFe2O4 by high energy ball milling (HEBM) of SnO and α-Fe2O3

    International Nuclear Information System (INIS)

    Uwakweh, Oswald N C; Perez Moyet, Richard; Mas, Rita; Morales, Carolyn; Vargas, Pedro; Silva, Josue; Rossa, Angel; Lopez, Neshma

    2010-01-01

    The formation of single phase nanoparticles of spinel structured ferrite, SnFe 2 O 4 , by mechanochemical syntheses using HEBM of stoichiometric amounts of solid SnO and α-Fe 2 O 3 with acetone as surfactant was achieved progressively as function of ball milling time. Single phase SnFe 2 O 4 formation commenced from five hours of continuous ball milling, and reached completion after 22 hours, thereby yielding a material with a lattice parameter of 8.543 A, and particle size of 10.91 nm. The coercivity was 4.44 mT, magnetic saturation value of 17.75 Am 2 /kg, and remanent magnetizations of 1.50 Am 2 /kg, correspondingly. The nanosized particles exhibited superparamagnetic behavior phenomenon based on Moessbauer spectroscopy measurements. The kinetic analyses based on the modified Kissinger method yielded four characteristic stages during the thermal evolution of the 22 hours milled state with activation energies of 0.23 kJ/mol, 2.52 kJ/mol, 0.024 kJ/mol, and 1.57 kJ/mol respectively.

  20. Phase segregation, interfacial intermetallic growth and electromigration-induced failure in Cu/In–48Sn/Cu solder interconnects under current stressing

    International Nuclear Information System (INIS)

    Li, Yi; Lim, Adeline B.Y.; Luo, Kaiming; Chen, Zhong; Wu, Fengshun; Chan, Y.C.

    2016-01-01

    The evolution of microstructure in Cu/In–48Sn/Cu solder bump interconnects at a current density of 0.7 × 10"4 A/cm"2 and ambient temperature of 55 °C has been investigated. During electromigration, tin (Sn) atoms migrated from cathode to anode, while indium (In) atoms migrated from anode to cathode. As a result, the segregation of the Sn-rich phase and the In-rich phase occurred. A Sn-rich layer and an In-rich layer were formed at the anode and the cathode, respectively. The accumulation rate of the Sn-rich layer was 1.98 × 10"−"9 cm/s. The atomic flux of Sn was calculated to be approximately 1.83 × 10"1"3 atoms/cm"2s. The product of the diffusivity and the effective charge number of Sn was determined to be approximately 3.13 × 10"−"1"0 cm"2/s. The In–48Sn/Cu IMC showed a two layer structure of Cu_6(Sn,In)_5, adjacent to the Cu, and Cu(In,Sn)_2, adjacent to the solder. Both the cathode IMC and the anode IMC thickened with increasing electromigration time. The IMC evolution during electromigration was strongly influenced by the migration of Cu atoms from cathode to anode and the accumulation of Sn-rich and In-rich layers. During electromigration, the Cu(In,Sn)_2 at the cathode interface thickened significantly, with a spalling characteristic, due to the accumulation of In-rich layer and the migration of Cu atoms - while the Cu(In,Sn)_2 at the anode interface reduced obviously, due to the accumulation of Sn-rich layer. The mechanism of electromigration-induced failure in Cu/In–48Sn/Cu interconnects was the cathode Cu dissolution-induced solder melt, which led to the rapid consumption of Cu in the cathode pad during liquid-state electromigration and this finally led to the failure. - Highlights: • Sn migrates to the anode, while In migrates to the cathode, during EM in Cu/In–48Sn/Cu. • The atomic flux of Sn has been calculated. • The interfacial IMCs were identified as: Cu_6(Sn,In)_5 + Cu(In,Sn)_2. • The interface evolution is strongly

  1. 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%.

  2. Synthesis and photocatalytic properties of different SnO{sub 2} microspheres on graphene oxide sheets

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Jia, E-mail: jojo.1125@hotmail.com [College of Science, Donghua University, Shanghai 201620 (China); Xue, Shaolin, E-mail: slxue@dhu.edu.cn [College of Science, Donghua University, Shanghai 201620 (China); Xie, Pei, E-mail: peipeixie@sina.com [College of Science, Donghua University, Shanghai 201620 (China); Zou, Rujia, E-mail: rujiazou@dhu.edu.cn [College of Science, Donghua University, Shanghai 201620 (China); State Key Laboratory for Modification of Chemical Fibers and Polymer Materials, College of Materials Science and Engineering, Donghua University, Shanghai 201620 (China)

    2016-07-15

    Highlights: • Different SnO{sub 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{sub 2} microspheres looks like dandelion. • The photocatalytic property is strongly influenced by the SnO{sub 2} morphology on GOs. - Abstract: Different SnO{sub 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{sub 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{sub 2} microspheres have tetragonal rutile structure. The results of Raman spectra, EDS, XRD, XPS and SEM showed that the SnO{sub 2} microspheres were grown on GOs and the average diameter of dandelion-like microsphere was about 1.5 μm. The formation mechanism of SnO{sub 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.

  3. Hierarchically structured carbon-coated SnO{sub 2}-Fe{sub 3}O{sub 4} microparticles with enhanced lithium storage performance

    Energy Technology Data Exchange (ETDEWEB)

    Chai, Xiaohan; Shi, Chunsheng [School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials, Tianjin University, Tianjin, 300072 (China); Liu, Enzuo [School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials, Tianjin University, Tianjin, 300072 (China); Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072 (China); Li, Jiajun [School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials, Tianjin University, Tianjin, 300072 (China); Zhao, Naiqin [School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials, Tianjin University, Tianjin, 300072 (China); Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072 (China); Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education, Tianjin University, Tianjin, 300072 (China); He, Chunnian, E-mail: cnhe08@tju.edu.cn [School of Materials Science and Engineering and Tianjin Key Laboratory of Composites and Functional Materials, Tianjin University, Tianjin, 300072 (China); Collaborative Innovation Center of Chemical Science and Engineering, Tianjin 300072 (China); Key Laboratory of Advanced Ceramics and Machining Technology, Ministry of Education, Tianjin University, Tianjin, 300072 (China)

    2016-01-15

    Graphical abstract: Hierarchically structured SnO{sub 2}-Fe{sub 3}O{sub 4}@C microparticles for lithium-ion battery anode are developed by a facile and scalable strategy. - Highlights: • Hierarchically structured SnO{sub 2}-Fe{sub 3}O{sub 4}@C micrometer-sized particles were synthesized. • The SnO{sub 2}-Fe{sub 3}O{sub 4}@C micrometer-sized particles deliver high reversible lithium storage capacity. • The wrapped carbon layer can buffer the volume expansion of SnO{sub 2}-Fe{sub 3}O{sub 4}. - Abstract: A facile and scalable strategy was developed to fabricate SnO{sub 2}-Fe{sub 3}O{sub 4}@C micrometer-sized particles as a good lithium-ion battery anode. The obtained materials were constructed by aggregated nanoclusters (100–200 nm) consisting of SnO{sub 2}-Fe{sub 3}O{sub 4}@C nanospheres (20 ∼ 30 nm), in which SnO{sub 2} and Fe{sub 3}O{sub 4} nanoparticles (5 ∼ 8 nm) were homogeneously embedded in a percolating carbonaceous network with an average thickness of about 3 nm. SnO{sub 2}-Fe{sub 3}O{sub 4}@C microparticles were synthesized by a one-pot hydrothermal process followed by annealing under Ar and subsequent chemical vapor transformation (CVT) under vacuum. The peculiar strategy allows to obtain hierarchical structure of micrometer-sized particles including nanospheres, nanoclusters and micro-scale particles, and the combination of SnO{sub 2} and Fe{sub 3}O{sub 4} could promote the synergistic effects to enhance the reversible capacity as well as the structural stability. Meanwhile, the carbon layer, homogeneously covering the nanoparticles does not only accommodate the volume change of active materials to maintain the structural integrity but also forms a conductive network throughout the whole micro-sized structure during charge/discharge processes. As a result, the electrode of SnO{sub 2}-Fe{sub 3}O{sub 4}@C microparticles exhibits good rate performance (1056 mAh g{sup −1} at 0.1 C, 734 mAh g{sup −1} at 0.2 C, 449 mAh g{sup −1} at 0.5 C, 212

  4. One step aqueous solution preparation of nanosize iron-doped tin oxide from SnO{sub 2}.xH{sub 2}O gel

    Energy Technology Data Exchange (ETDEWEB)

    Melghit, Khaled [Chemistry Department, College of Science, P.O. Box 36, Al-Khodh 123, Sultan Qaboos University (Oman)]. E-mail: melghit@squ.edu.om; Bouziane, Khalid [Physics Department, College of Science, P.O. Box 36, Al-Khodh 123, Sultan Qaboos University (Oman)

    2006-03-15

    Nanosized iron-doped tin oxide solid solution was prepared by mixing tin oxide gel SnO{sub 2}.xH{sub 2}O with a boiling solution of iron nitrate. The XRD data of the as-prepared and annealed sample at 773 K show that the patterns are indexed to the rutile phase without any trace of an extra phase. SEM and TEM results performed on different selected area of the samples reveal a homogeneous composition of 8 at.% of Fe content and a size of about 2 nm of the particles. The particles size was found to increase slightly with temperature; about 7 nm after 24 h at 773 K. Structural and magnetic results seem to indicate that Fe{sup 3+} substitute for Sn{sup 4+} on the as-prepared sample. The system presents some weak ferromagnetic character at room temperature.

  5. Binder-free ZnO@ZnSnO3 quantum dots core-shell nanorod array anodes for lithium-ion batteries

    Science.gov (United States)

    Tan, Hsiang; Cho, Hsun-Wei; Wu, Jih-Jen

    2018-06-01

    In this work, ZnSnO3 quantum dots (QDs), instead of commonly used conductive carbon, are grown on the ZnO nanorod (NR) array to construct the binder-free ZnO@ZnSnO3 QDs core-shell NR array electrode on carbon cloth for lithium-ion battery. The ZnO@ZnSnO3 QDs core-shell NR array electrode exhibits excellent lithium storage performance with an improved cycling performance and superior rate capability compared to the ZnO NR array electrode. At a current density of 200 mAg-1, 15.8% capacity loss is acquired in the ZnO@ZnSnO3 QDs core-shell NR array electrode after 110 cycles with capacity retention of 1073 mAhg-1. Significant increases in reversible capacities from 340 to 545 mAhg-1 and from 95 to 390 mAhg-1 at current densities of 1000 and 2000 mAg-1, respectively, are achieved as the ZnO NR arrays are coated with the ZnSnO3 QD shells. The remarkably improved electrochemical performances result from that the configuration of binder-free ZnO@ZnSnO3 QDs core-shell NR array electrode not only facilitates the charge transfer through the solid electrolyte interface and the electronic/ionic conduction boundary as well as lithium ion diffusion but also effectively accommodates the volume change during repeated charge/discharge processes.

  6. Structure in the 12C+ 12C and 8Be+16O fission width distribution of 24Mg observed via the reaction 12C(16O,α)24Mg(→X+Y)

    International Nuclear Information System (INIS)

    Lazzarini, A.J.; Steadman, S.G.; Ledoux, R.J.; Sperduto, A.; Young, G.R.; Van Bibber, K.; Cosman, E.R.

    1983-01-01

    Prominent gross and intermediate width structures are observed in the 12 C+ 12 C, 12 C+ 12 C((2 + ), 1 C((2 + )+ 12 C((2 + ), 8 Be+ 16 O, and 8 Be+ 16 O + (3 - , O + ) decay channels following 24 Mg* population via the 12 C( 16 O,α) 24 Mg reaction at E/sub c.m./ = 33 MeV. Evidence that the 12 C( 16 O,α) 24 Mg reaction populates states in 24 Mg which are associated with 12 C+ 12 C resonances is presented in the form of correlation analyses between the α+ 12 C+ 12 C three-body spectra and previously measured 12 C+ 12 C elastic and inelastic excitation functions. Direct determination of 12 C+ 12 C widths from these measurements is obscured by a background of other strong transitions which appear to be present in the 12 C( 16 O,α) 24 Mg singles spectrum

  7. Electronic characteristics of p-type transparent SnO monolayer with high carrier mobility

    International Nuclear Information System (INIS)

    Du, Juan; Xia, Congxin; Liu, Yaming; Li, Xueping; Peng, Yuting; Wei, Shuyi

    2017-01-01

    Graphical abstract: SnO monolayer is a p-type transparent semiconducting oxide with high hole mobility (∼641 cm 2 V −1 s −1 ), which is much higher than that of MoS 2 monolayer, which indicate that it can be a promising candidate for high-performance nanoelectronic devices. Display Omitted - Highlights: • SnO monolayer is a p-type transparent semiconducting oxide. • The transparent properties can be still maintained under the strain 8%. • It has a high hole mobility (∼641 cm 2 V −1 s −1 ), which is higher than that of MoS 2 monolayer. - Abstract: More recently, two-dimensional (2D) SnO nanosheets are attaching great attention due to its excellent carrier mobility and transparent characteristics. Here, the stability, electronic structures and carrier mobility of SnO monolayer are investigated by using first-principles calculations. The calculations of the phonon dispersion spectra indicate that SnO monolayer is dynamically stable. Moreover, the band gap values are decreased from 3.93 eV to 2.75 eV when the tensile strain is applied from 0% to 12%. Interestingly, SnO monolayer is a p-type transparent semiconducting oxide with hole mobility of 641 cm 2 V −1 s −1 , which is much higher than that of MoS 2 monolayer. These findings make SnO monolayer becomes a promising 2D material for applications in nanoelectronic devices.

  8. CO gas sensing properties of In_4Sn_3O_1_2 and TeO_2 composite nanoparticle sensors

    International Nuclear Information System (INIS)

    Mirzaei, Ali; Park, Sunghoon; Sun, Gun-Joo; Kheel, Hyejoon; Lee, Chongmu

    2016-01-01

    Highlights: • In4Sn3O12–TeO2 composite nanoparticles were synthesized via a facile hydrothermal route. • The response of the In4Sn3O12–TeO2 composite sensor to CO was stronger than the pristine In4Sn3O12 sensor. • The response of the In4Sn3O12–TeO2 composite sensor to CO was faster than the pristine In4Sn3O12 sensor. • The improved sensing performance of the In4Sn3O12–TeO2 nanocomposite sensor is discussed in detail. • The In4Sn3O12-based nanoparticle sensors showed selectivity to CO over NH3, HCHO and H2. - Abstract: A simple hydrothermal route was used to synthesize In_4Sn_3O_1_2 nanoparticles and In_4Sn_3O_1_2–TeO_2 composite nanoparticles, with In(C_2H_3O_2)_3, SnCl_4, and TeCl_4 as the starting materials. The structure and morphology of the synthesized nanoparticles were examined by X-ray diffraction and scanning electron microscopy (SEM), respectively. The gas-sensing properties of the pure and composite nanoparticles toward CO gas were examined at different concentrations (5–100 ppm) of CO gas at different temperatures (100–300 °C). SEM observation revealed that the composite nanoparticles had a uniform shape and size. The sensor based on the In_4Sn_3O_1_2–TeO_2 composite nanoparticles showed stronger response to CO than its pure In_4Sn_3O_1_2 counterpart. The response of the In_4Sn_3O_1_2–TeO_2 composite-nanoparticle sensor to 100 ppm of CO at 200 °C was 10.21, whereas the maximum response of the In_4Sn_3O_1_2 nanoparticle sensor was 2.78 under the same conditions. Furthermore, the response time of the composite sensor was 19.73 s under these conditions, which is less than one-third of that of the In_4Sn_3O_1_2 sensor. The improved sensing performance of the In_4Sn_3O_1_2–TeO_2 nanocomposite sensor is attributed to the enhanced modulation of the potential barrier height at the In_4Sn_3O_1_2–TeO_2 interface, the stronger oxygen adsorption of p-type TeO_2, and the formation of preferential adsorption sites.

  9. Sandwich-like C@SnO2/Sn/void@C hollow spheres as improved anode materials for lithium ion batteries

    Science.gov (United States)

    Wang, Huijun; Jiang, Xinya; Chai, Yaqin; Yang, Xia; Yuan, Ruo

    2018-03-01

    As lithium ion batteries (LIBs) anode, SnO2 suffers fast capacity fading due to its large volume expansion during discharge/charge process. To overcome the problem, sandwich-like C@SnO2/Sn/void@C hollow spheres (referred as C@SnO2/Sn/void@C HSs) are prepared by in-situ polymerization and carbonization, using hollow SnO2 as self-template and dopamine as carbon source. The C@SnO2/Sn/void@C HSs possesses the merits of hollow and core/void/shell structure, so that they can accommodate the volume change under discharge/charge process, shorten the transmission distance of Li ions, own more contact area for the electrolyte. Thanks to these advantages, C@SnO2/Sn/void@C HSs display excellent electrochemical performance as anode materials for LIBs, which deliver a high capacity of 786.7 mAh g-1 at the current density of 0.5 A g-1 after 60 cycles. The simple synthesis method for C@SnO2/Sn/void@C HSs with special structure will provide a promising method for preparing other anode materials for LIBs.

  10. Synthesis and photoluminescence of Ca-(Sn,Ti)-Si-O compounds

    International Nuclear Information System (INIS)

    Abe, Shunsuke; Yamane, Hisanori; Yoshida, Hisashi

    2010-01-01

    The phase relation of the compounds prepared in the CaO-SnO 2 -SiO 2 system at 1673 K and in the CaO-TiO 2 -SiO 2 system at 1573 K was investigated in order to explore new Ti 4+ -activated stannate phosphors. Solid solutions of Ca(Sn 1-x Ti x )SiO 5 and Ca 3 (Sn 1-y Ti y )Si 2 O 9 were synthesized at x = 0-1.0 and y = 0-0.10, respectively, and their crystal structures were analyzed by powder X-ray diffraction. Photoluminescence of these solid solutions was observed in a broad range of a visible light wavelength region under ultraviolet (UV) light excitation. The peaks of the emission band of Ca(Sn 0.97 Ti 0.03 )SiO 5 and Ca 3 (Sn 0.925 Ti 0.075 )Si 2 O 9 were at 510 nm under excitation of 252 nm and at 534 nm under excitation of 258 nm, respectively. The absorption edges estimated by the diffuse reflectance spectra were at 300 nm (4.1 eV) for CaSnSiO 5 and at 270 nm (4.6 eV) for Ca 3 SnSi 2 O 9 , suggesting that the excitation levels in Ca(Sn 1-x Ti x )SiO 5 were above the band gap of the host, although the levels in Ca 3 (Sn 1-y Ti y )Si 2 O 9 were within the band gap and near the conduction band edge.

  11. 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.

  12. 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.

  13. Systematic and controllable negative, zero, and positive thermal expansion in cubic Zr(1-x)Sn(x)Mo2O8.

    Science.gov (United States)

    Tallentire, Sarah E; Child, Felicity; Fall, Ian; Vella-Zarb, Liana; Evans, Ivana Radosavljević; Tucker, Matthew G; Keen, David A; Wilson, Claire; Evans, John S O

    2013-08-28

    We describe the synthesis and characterization of a family of materials, Zr1-xSnxMo2O8 (0 thermal expansion coefficient can be systematically varied from negative to zero to positive values. These materials allow tunable expansion in a single phase as opposed to using a composite system. Linear thermal expansion coefficients, αl, ranging from -7.9(2) × 10(-6) to +5.9(2) × 10(-6) K(-1) (12-500 K) can be achieved across the series; contraction and expansion limits are of the same order of magnitude as the expansion of typical ceramics. We also report the various structures and thermal expansion of "cubic" SnMo2O8, and we use time- and temperature-dependent diffraction studies to describe a series of phase transitions between different ordered and disordered states of this material.

  14. 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.

  15. 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.

  16. ZnO/SnO{sub 2} nanoflower based ZnO template synthesized by thermal chemical vapor deposition

    Energy Technology Data Exchange (ETDEWEB)

    Sin, N. D. Md., E-mail: diyana0366@johor.uitm.edu.my; Amalina, M. N., E-mail: amalina0942@johor.uitm.edu.my [NANO-ElecTronic Centre, Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); Fakulti Kejuruteraan Elektrik, Universiti Teknologi MARA Cawangan Johor, Kampus Pasir Gudang, 81750 Masai, Johor (Malaysia); Ismail, Ahmad Syakirin, E-mail: kyrin-samaxi@yahoo.com; Shafura, A. K., E-mail: shafura@ymail.com; Ahmad, Samsiah, E-mail: samsiah.ahmad@johor.uitm.edu.my; Mamat, M. H., E-mail: mhmamat@salam.uitm.edu.my [NANO-ElecTronic Centre, Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); Rusop, M., E-mail: rusop@salam.uitm.edu.my [NANO-ElecTronic Centre, Faculty of Electrical Engineering, Universiti Teknologi MARA (UiTM), 40450 Shah Alam, Selangor (Malaysia); NANO-SciTech Centre (NST), Institute of Science (IOS), Universiti Teknologi MARA - UiTM, 40450 Shah Alam, Selangor (Malaysia)

    2016-07-06

    The ZnO/SnO{sub 2} nanoflower like structures was grown on a glass substrate deposited with seed layer using thermal chemical vapor deposition (CVD) with combining two source materials. The ZnO/SnO{sub 2} nanoflower like structures had diameter in the range 70 to 100 nm. The atomic percentage of ZnO nanoparticle , SnO{sub 2} nanorods and ZnO/SnO{sub 2} nanoflower was taken using EDS. Based on the FESEM observations, the growth mechanism is applied to describe the growth for the synthesized nanostructures.

  17. Zr-rich corner of the Zr-Sn-O diagram

    International Nuclear Information System (INIS)

    Roberti, L.A.; Arias, D.E.

    1993-01-01

    The understanding of the effect of light elements (in particular oxygen, nitrogen and hydrogen) on the behaviour of alloys for nuclear use is necessary because of its technological importance. The Zr-Sn-O system is perhaps the most representative of all possible ternary systems which can be used to simulate a simplified Zircaloy-type alloy in which the effect of O can be studied. However, in the specialized literature experimental data on phase equilibria and thermophysical properties of this system are not easily found. In the present work, the equilibrium compositions of the α and β phases of the Zr-Sn-O system at temperatures between 1150 and 1323 K are calculated, using the scarce available information. First results of the calculations show satisfactory coincidences with experimental data. Future work will be oriented towards the proposal of isothermal cross-sections calculated by a modelling of phases with wider Sn and O composition ranges, and involving equilibria with the phases Zr 4 Sn, Zr 5 Sn 3 , ZrO 2 , ZrSnO 4 . (Author)

  18. 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.

  19. Magnetostructural transformation and magnetocaloric effect in Mn48‑x V x Ni42Sn10 ferromagnetic shape memory alloys

    Science.gov (United States)

    Hassan, Najam ul; Shah, Ishfaq Ahmad; Khan, Tahira; Liu, Jun; Gong, Yuanyuan; Miao, Xuefei; Xu, Feng

    2018-03-01

    In this work, we tuned the magnetostructural transformation and the coupled magnetocaloric properties of Mn48‑x V x Ni42Sn10 (x = 0, 1, 2, and 3) ferromagnetic shape memory alloys prepared by means of partial replacement of Mn by V. It is observed that the martensitic transformation temperatures decrease with the increase of V content. The shift of the transition temperatures to lower temperatures driven by the applied field, the metamagnetic behavior, and the thermal hysteresis indicates the first-order nature for the magnetostructural transformation. The entropy changes with a magnetic field variation of 0–5 T are 15.2, 18.8, and 24.3 {{J}}\\cdot {kg}}-1\\cdot {{{K}}}-1 for the x = 0, 1, and 2 samples, respectively. The tunable martensitic transformation temperature, enhanced field driving capacity, and large entropy change suggest that Mn48‑x V x Ni42Sn10 alloys have a potential for applications in magnetic cooling refrigeration. Project supported by the National Natural Science Foundation of China (Grant Nos. 51601092, 51571121, and 11604148), the Fundamental Research Funds for the Central Universities, China (Grant Nos. 30916011344 and 30916011345), the Fund Program for the Scientific Activities of Selected Returned Overseas Professionals in Shanxi Province, China, the Postdoctoral Science Foundation Funded Project (Grant No. 2016M591851), the Natural Science Foundation of Jiangsu Province, China (Grant Nos. BK20160833, 20160829, and 20140035), the Qing Lan Project of Jiangsu Province, the Priority Academic Program Development of Jiangsu Higher Education Institutions, and Shanxi Scholarship Council of China (Grant No. 2016-092).

  20. 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.

  1. Electronic characteristics of p-type transparent SnO monolayer with high carrier mobility

    Energy Technology Data Exchange (ETDEWEB)

    Du, Juan [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Xia, Congxin, E-mail: xiacongxin@htu.edu.cn [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Liu, Yaming [Henan Institute of Science and Technology, Xinxiang 453003 (China); Li, Xueping [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China); Peng, Yuting [Department of Physics, University of Texas at Arlington, TX 76019 (United States); Wei, Shuyi [College of Physics and Materials Science, Henan Normal University, Xinxiang, Henan 453007 (China)

    2017-04-15

    Graphical abstract: SnO monolayer is a p-type transparent semiconducting oxide with high hole mobility (∼641 cm{sup 2} V{sup −1} s{sup −1}), which is much higher than that of MoS{sub 2} monolayer, which indicate that it can be a promising candidate for high-performance nanoelectronic devices. Display Omitted - Highlights: • SnO monolayer is a p-type transparent semiconducting oxide. • The transparent properties can be still maintained under the strain 8%. • It has a high hole mobility (∼641 cm{sup 2} V{sup −1} s{sup −1}), which is higher than that of MoS{sub 2} monolayer. - Abstract: More recently, two-dimensional (2D) SnO nanosheets are attaching great attention due to its excellent carrier mobility and transparent characteristics. Here, the stability, electronic structures and carrier mobility of SnO monolayer are investigated by using first-principles calculations. The calculations of the phonon dispersion spectra indicate that SnO monolayer is dynamically stable. Moreover, the band gap values are decreased from 3.93 eV to 2.75 eV when the tensile strain is applied from 0% to 12%. Interestingly, SnO monolayer is a p-type transparent semiconducting oxide with hole mobility of 641 cm{sup 2} V{sup −1} s{sup −1}, which is much higher than that of MoS{sub 2} monolayer. These findings make SnO monolayer becomes a promising 2D material for applications in nanoelectronic devices.

  2. 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

  3. Hydrothermal Synthesis and Structural Characterization of NiO/SnO2 Composites and Hydrogen Sensing Properties

    Directory of Open Access Journals (Sweden)

    Chao Wei

    2015-01-01

    Full Text Available Pure SnO2 and NiO doped SnO2 nanostructures were successfully synthesized via a simple and environment-friendly hydrothermal method. X-ray powder diffraction (XRD, scanning electron microscopy (SEM, energy dispersive X-ray spectroscopy (EDS, and X-ray photoelectron spectra (XPS were used to investigate the crystalline structures, surface morphologies and microstructures, and element components and their valences of the as-synthesized samples. Furthermore, planar chemical gas sensors based on the synthesized pure SnO2 and NiO/SnO2 composites were fabricated and their sensing performances to hydrogen, an important fault characteristic gas dissolved in power transformer oil, were investigated in detail. Gas sensing experiments indicate that the NiO/SnO2 composites showed much higher gas response and lower working temperature than those of pure SnO2, which could be ascribed to the formation of p-n heterojunctions between p-type NiO and n-type SnO2. These results demonstrate that the as-synthesized NiO/SnO2 composites a promising hydrogen sensing material.

  4. Nonohmic behavior of SnO2.MnO2-based ceramics

    Directory of Open Access Journals (Sweden)

    Marcelo O. Orlandi

    2003-06-01

    Full Text Available The present paper describes the nonohmic behavior of the SnO2.MnO-based system and analyzes the influence of the sintering time and the Nb2O5 concentration on this system's electrical properties. A nonlinear coefficient of ~7 was obtained for a 0.2 mol%-doped Nb2O5 composition, which is comparable to other values reported in the literature for the ternary SnO2-based systems. A recent barrier formation model proposed in the literature to explain the nonlinear electrical behavior of SnO2-based systems is used to clarify the role of the MnO constituent in the formation of the barrier, taking into account the influence of segregated atoms, precipitated phase and oxygen species in the grain boundary region.

  5. 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)

  6. Large-scale preparation of shape controlled SnO and improved capacitance for supercapacitors: from nanoclusters to square microplates

    Science.gov (United States)

    Wang, Lu; Ji, Hongmei; Zhu, Feng; Chen, Zhi; Yang, Yang; Jiang, Xuefan; Pinto, João; Yang, Gang

    2013-07-01

    Here, we first provide a facile ultrasonic-assisted synthesis of SnO using SnCl2 and the organic solvent of ethanolamine (ETA). The moderate alkalinity of ETA and ultrasound play very important roles in the synthesis of SnO. After the hydrolysis of the intermediate of ETA-Sn(ii), the as-synthesized SnO nanoclusters undergo assembly, amalgamation, and preferential growth to microplates in hydrothermal treatment. The as-synthesized SnO was characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), ultraviolet-visible absorption spectroscopy (UV-vis) and X-ray diffraction (XRD). To explore its potential applications in energy storage, SnO was fabricated into a supercapacitor electrode and characterized by cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and galvanostatic charge-discharge measurements. The as-synthesized SnO exhibits remarkable pseudocapacitive activity including high specific capacitance (208.9 F g-1 at 0.1 A g-1), good rate capability (65.8 F g-1 at 40 A g-1), and excellent cycling stability (retention 119.3% after 10 000 cycles) for application in supercapacitors. The capacitive behavior of SnO with various crystal morphologies was observed by fitted EIS using an equivalent circuit. The novel synthetic route for SnO is a convenient and potential way to large-scale production of microplates which is expected to be applicable in the synthesis of other metal oxide nanoparticles.Here, we first provide a facile ultrasonic-assisted synthesis of SnO using SnCl2 and the organic solvent of ethanolamine (ETA). The moderate alkalinity of ETA and ultrasound play very important roles in the synthesis of SnO. After the hydrolysis of the intermediate of ETA-Sn(ii), the as-synthesized SnO nanoclusters undergo assembly, amalgamation, and preferential growth to microplates in hydrothermal treatment. The as-synthesized SnO was characterized by scanning

  7. Role of different chelating agent in synthesis of copper doped tin oxide (Cu-SnO2) nanoparticles

    Science.gov (United States)

    Saravanakumar, B.; Anusiya, A.; Rani, B. Jansi; Ravi, G.; Yuvakkumar, R.

    2018-05-01

    An attempt was made to synthesis the copper doped tin oxide (Cu-SnO2) nanoparticles by adopting different chelating agents (NaOH, KOH and C2H2O4) by Sol-gel process. The synthesized products were characterized by XRD, Photoluminescence (PL), Infra- Red (FTIR) and SEM analysis. The XRD confirms the formation of Cu-SnO2 shows the maximum peak at 33.8° with lattice plane (101). The PL peak at 361 and 382 nm due to the recombination of electron in conduction band to valence band infers the optical properties. The IR spectra correspond to the peak at 551 and 620 cm-1 attributed to the characteristics peak for Cu-SnO2 nanoparticles. The SEM images for all three Cu-SnO2 nanoparticles formed by three chelating agent (NaOH, KOH and C2H2O4) facilitates the formation mechanism and the chelating agent Oxalic acid results in formation of nano flowers with diverse layers orientated in random direction. Further SEM studies reveal that, the Cu-SnO2 nanoparticles formed by oxalic acid could posses high surface area with large number layered structured enables the better electrochemical properties and its applications.

  8. Hydrothermal synthesis and characteristic photoluminescence of Er-doped SnO{sub 2} nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Tuan, Pham Van; Hieu, Le Trung; Nga, La Quynh [International Training Institute for Materials Science, Hanoi University of Science and Technology, No.1, Dai Co Viet, Hanoi (Viet Nam); Dung, Nguyen Duc [Advanced Institute of Science and Technology, Hanoi University of Science and Technology, No.1, Dai Co Viet, Hanoi (Viet Nam); Ha, Ngo Ngoc [International Training Institute for Materials Science, Hanoi University of Science and Technology, No.1, Dai Co Viet, Hanoi (Viet Nam); Khiem, Tran Ngoc, E-mail: khiem@itims.edu.vn [International Training Institute for Materials Science, Hanoi University of Science and Technology, No.1, Dai Co Viet, Hanoi (Viet Nam)

    2016-11-15

    We report the characteristic photoluminescence (PL) spectra of erbium ion (Er{sup 3+})-doped tin dioxide (SnO{sub 2})nanoparticles. The materials were prepared via hydrothermal method at 180 °C with in 20 h by using various Er{sup 3+} ion concentrations ranging from 0.0 to 1.0 at%. After the synthesis, the materials were characterized through X-ray diffraction and high-resolution transmission electron microscopy. Crystallite SnO{sub 2} and its average particle diameter of approximately 5 nm did not change with Er{sup 3+} ion dopant concentration. Photoluminescence spectra showed the characteristic light emission from the Er{sup 3+} ions. The PL excitation spectra referred to an efficient energy transfer to Er{sup 3+} ions in the presence of SnO{sub 2}nanoparticles. The most intense Er-related emission of SnO{sub 2}:Er{sup 3+} nanoparticles in near infrared region was found in samples containing an Er{sup 3+} ion concentration of 0.25 at%. Although the absorption bandgaps of the materials were identified at approximately 3.8 eV, we found that efficient excitation comes with low excitation energy band edge. Excitation is possibly involved in shallow defects in SnO{sub 2} nanoparticles.

  9. 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.

  10. Synthesis and Characterization of TiO2(B Nanotubes Prepared by Hydrothermal Method Using [Ti8O12(H2O24]Cl8.HCl.7H2O as Precursor

    Directory of Open Access Journals (Sweden)

    Hari Sutrisno

    2010-04-01

    Full Text Available Low-dimension TiO2-related material has been synthesized by hydrothermal treatment of [Ti8O12(H2O24]Cl8.HCl.7H2O crystal as precursor in a 10 M NaOh aqueous solution at 150 C for 24 h. Characterization of the obtained product was carried out by a range of techniques including X-ray diffraction (XRD, high resolution scanning electron microscopy (HRSEM, high resolution transmission electron microscopy (HRTEM, Raman spectroscopy and nitrogen adsorption-desorption isotherm (Brunauer-Emmett-Teller (BET-Barret-Joyner-Halender (BJH. From HRTEM, XRD and Raman spectra showed that the obtained product has a TiO2(B structure. According to HRTEM observations, it was found that TiO2(B has nanotubular structure with approximately 5-8 nm in outer and 3-6 nm in inner diameter. The BET surface area of TiO2(B nanotubes is quiet large, values of 418.3163 m2/g being obtained. Pore structure analyisis by the BJH method showed that the average pore diameter of TiO2(B nanotubes has 5.5781 nm.

  11. Synthesis mechanism of heterovalent Sn2O3 nanosheets in oxidation annealing process

    International Nuclear Information System (INIS)

    Zhao Jun-Hua; Wu Guo-Qiang; Yang Xu-Feng; Tan Rui-Qin; Yang Ye; Xu Wei; Li Jia; Shen Wen-Feng; Song Wei-Jie

    2015-01-01

    Heterovalent Sn 2 O 3 nanosheets were fabricated via an oxidation annealing process and the formation mechanism was investigated. The temperature required to complete the phase transformation from Sn 3 O 4 to Sn 2 O 3 was considered. Two contrasting experiments showed that both oxygen and heating were not necessary conditions for the phase transition. Sn 2 O 3 was formed under an argon protective atmosphere by annealing and could also be obtained at room temperature by exposing Sn 3 O 4 in atmosphere or dispersing in ethanol. The synthesis mechanism was proposed and discussed. This fundamental research is important for the technological applications of intermediate tin oxide materials. (paper)

  12. Voids, nanochannels and formation of nanotubes with mobile Sn fillings in Sn doped ZnO nanorods

    International Nuclear Information System (INIS)

    Ortega, Y; Dieker, Ch; Jaeger, W; Piqueras, J; Fernandez, P

    2010-01-01

    ZnO nanorods containing different hollow structures have been grown by a thermal evaporation-deposition method with a mixture of ZnS and SnO 2 powders as precursor. Transmission electron microscopy shows rods with rows of voids as well as rods with empty channels along the growth axis. The presence of Sn nanoprecipitates associated with the empty regions indicates, in addition, that these are generated by diffusion processes during growth, probably due to an inhomogeneous distribution of Sn. The mechanism of forming voids and precipitates appears to be based on diffusion processes similar to the Kirkendall effect, which can lead to void formation at interfaces of bulk materials or in core-shell nanostructures. In some cases the nanorods are ZnO tubes partially filled with Sn that has been found to melt and expand by heating the nanotubes under the microscope electron beam. Such metal-semiconductor nanostructures have potential applications as thermal nanosensors or as electrical nanocomponents.

  13. Wetting behavior of molten In-Sn alloy on bulk amorphous and crystalline Cu40Zr44Al8Ag8

    International Nuclear Information System (INIS)

    Ma, G. F.; Zhang, H. F.; Li, H.; Hu, Z. Q.

    2007-01-01

    Using the sessile-drop method, the wettability of the molten In-Sn alloy on bulk amorphous and crystalline Cu 40 Zr 44 Al 8 Ag 8 alloy was studied at different temperatures. It was found that the equilibrium contact angle of In-Sn alloy melt on bulk amorphous substrate was smaller than that of the crystalline one. An intermetallic compound existed at the interface of In-Sn alloy on amorphous Cu 40 Zr 44 Al 8 Ag 8 , while no intermediate reaction layer was formed at the interface of In-Sn alloy on crystalline Cu 40 Zr 44 Al 8 Ag 8 in the temperature range studied

  14. Structural, optical and thermal characterization of PVC/SnO2 nanocomposites

    Science.gov (United States)

    Taha, T. A.; Ismail, Z.; Elhawary, M. M.

    2018-04-01

    The structural, optical, and thermal properties of PVC/SnO2 nanocomposites were investigated. XRD patterns were used to explore the structures of these prepared samples. Optical UV-Vis measurements were analyzed to calculate the spectroscopic optical constants of the prepared PVC/SnO2 nanocomposites. Both direct and indirect optical band gaps decreased with increasing SnO2 content. The refractive index, high frequency dielectric constant, plasma frequency, and optical conductivity values increased with SnO2. The single oscillator energy increased from 5.64 to 10.97 eV and the dispersion energy increased from 6.35 to 19.80 eV with the addition of SnO2. The other optical parameters such as optical moments, single oscillator strength, volume energy loss, and surface energy loss were calculated for different SnO2 concentrations. Raman spectra of the PVC/SnO2 nanocomposite films revealed the characteristic vibrational modes of PVC and surface phonon modes of SnO2. The thermal stability of PVC/SnO2 nanocomposite films was studied using DTA and thermogravimetric analysis. The glass transition ( T g) values abruptly changed from 46 °C for PVC to an average value of 59 °C for the polymer films doped with 2.0, 4.0, and 6.0 wt% SnO2. The weight loss decreased as the SnO2 concentration increased in the temperature range of 350-500 °C, corresponding to enhanced thermal stability.

  15. Facile surfactant- and template-free synthesis and electrochemical properties of SnO{sub 2}/graphene composites

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jing, E-mail: xy13787103391@126.com [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Zhang, Xia, E-mail: zyx02090229@163.com [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Guo, Jianqiang; Peng, Rufang [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China); Xie, Ruishi [Analytical and Testing Center, Southwest University of Science and Technology, Mianyang 621010 (China); Huang, Yeju; Qi, Yongcheng [School of Materials Science and Engineering, Southwest University of Science and Technology, Mianyang 621010 (China); State Key Laboratory Cultivation Base for Nonmetal Composites and Functional Materials, Southwest University of Science and Technology, Mianyang 621010 (China)

    2016-07-25

    In this work, we demonstrate a facile and green hydrothermal process without using any surfactant or template to synthesize SnO{sub 2} nanoflowers (NFs)/graphene nanosheets (GNSs) composites as a high-performance electrode material for electric double layer capacitors (EDLCs). The crystal structure and morphology of the products were characterized by X-ray diffraction, scanning electron microscopy, and transition electron microscopy. The electrochemical properties were investigated by galvanostatic charge/discharge cycling and cycling voltammetry in a voltage range of −0.2–0.8 V. The results exhibit that the addition of GNSs did not change the tetragonal crystal structure of SnO{sub 2}, and the GNSs were successfully coated on the flower-like surface of SnO{sub 2}. The grain morphology of SnO{sub 2}@GNSs composites has a flower-like appearance suggesting excellent electrochemical properties which were confirmed by electrochemical techniques. Compared with the GNSs, the SnO{sub 2}@GNSs composites exhibit a high specific discharge capacitance of 126 F g{sup −1} at 0.2 A g{sup −1} and remains 98.2% after 2000 charge–discharge cycles. The combination of GNSs and SnO{sub 2} could significantly improve the electrical conductivity, enhance the interactions between GNSs and SnO{sub 2} NFs and provide more reaction sites, thereby resulting in improved electrochemical properties for the SnO{sub 2}@GNSs composites in contrast with the pristine GNSs sample. The high specific capacity and long stability make the SnO{sub 2}@GNSs nanocomposite as a electrode material for high-performance supercapacitors. - Highlights: • SnO{sub 2} nanoflowers (NFs)/Graphene nanosheets(GNSs) composites were prepared by a simple and rapid hydrothermal process. • The results show that the GNSs were homogeneously and tightly attached on the surface of SnO{sub 2} NFs. • The SnO{sub 2} NFs/GNSs composites electrode exhibited the enhanced capacitive performances than those of pure GNSs.

  16. SnO2/ZnO composite structure for the lithium-ion battery electrode

    International Nuclear Information System (INIS)

    Ahmad, Mashkoor; Yingying, Shi; Sun, Hongyu; Shen, Wanci; Zhu, Jing

    2012-01-01

    In this article, SnO 2 /ZnO composite structures have been synthesized by two steps hydrothermal method and investigated their lithium storage capacity as compared with pure ZnO. It has been found that these composite structures combining the large specific surface area, stability and catalytic activity of SnO 2 micro-crystals, demonstrate the higher initial discharge capacity of 1540 mA h g −1 with a Coulombic efficiency of 68% at a rate of 120 mA h g −1 between 0.02 and 2 V and found much better than that of any previously reported ZnO based composite anodes. In addition, a significantly enhanced cycling performance, i.e., a reversible capacity of 497 mA h g −1 is retained after 40 cycles. The improved lithium storage capacity and cycle life is attributed to the addition of SnO 2 structure, which act as good electronic conductors and better accommodation of the large volume change during lithiation/delithiation process. - Graphical abstract: SnO 2 /ZnO composite structures demonstrate the improved lithium storage capacity and cycle life as compared with pure ZnO nanostructure. Highlights: ► Synthesis of SnO 2 /ZnO composite structures by two steps hydrothermal approach. ► Investigation of lithium storage capacity. ► Excellent lithium storage capacity and cycle life of SnO 2 /ZnO composite structures.

  17. Design and assembly of ternary Pt/Re/SnO2 NPs by controlling the zeta potential of individual Pt, Re, and SnO2 NPs

    Science.gov (United States)

    Drzymała, Elżbieta; Gruzeł, Grzegorz; Pajor-Świerzy, Anna; Depciuch, Joanna; Socha, Robert; Kowal, Andrzej; Warszyński, Piotr; Parlinska-Wojtan, Magdalena

    2018-05-01

    In this study Pt, Re, and SnO2 nanoparticles (NPs) were combined in a controlled manner into binary and ternary combinations for a possible application for ethanol oxidation. For this purpose, zeta potentials as a function of the pH of the individual NPs solutions were measured. In order to successfully combine the NPs into Pt/SnO2 and Re/SnO2 NPs, the solutions were mixed together at a pH guaranteeing opposite zeta potentials of the metal and oxide NPs. The individually synthesized NPs and their binary/ternary combinations were characterized by Fourier transform infrared spectroscopy (FTIR) and scanning transmission electron microscopy (STEM) combined with energy dispersive X-ray spectroscopy (EDS) analysis. FTIR and XPS spectroscopy showed that the individually synthesized Pt and Re NPs are metallic and the Sn component was oxidized to SnO2. STEM showed that all NPs are well crystallized and the sizes of the Pt, Re, and SnO2 NPs were 2.2, 1.0, and 3.4 nm, respectively. Moreover, EDS analysis confirmed the successful formation of binary Pt/SnO2 and Re/SnO2 NP, as well as ternary Pt/Re/SnO2 NP combinations. This study shows that by controlling the zeta potential of individual metal and oxide NPs, it is possible to assemble them into binary and ternary combinations. [Figure not available: see fulltext.

  18. 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.

  19. 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.

  20. Thermodynamic, electronic, and magnetic properties of intrinsic vacancy defects in antiperovskite Ca3SnO

    Science.gov (United States)

    Batool, Javaria; Alay-e-Abbas, Syed Muhammad; Amin, Nasir

    2018-04-01

    The density functional theory based total energy calculations are performed to examine the effect of charge neutral and fully charged intrinsic vacancy defects on the thermodynamic, electronic, and magnetic properties of Ca3SnO antiperovskite. The chemical stability of Ca3SnO is evaluated with respect to binary compounds CaO, CaSn, and Ca2Sn, and the limits of atomic chemical potentials of Ca, Sn, and O atoms for stable synthesis of Ca3SnO are determined within the generalized gradient approximation parametrization scheme. The electronic properties of the pristine and the non-stoichiometric forms of this compound have been explored and the influence of isolated intrinsic vacancy defects (Ca, Sn, and O) on the structural, bonding, and electronic properties of non-stoichiometric Ca3SnO are analyzed. We also predict the possibility of achieving stable ferromagnetism in non-stoichiometric Ca3SnO by means of charge neutral tin vacancies. From the calculated total energies and the valid ranges of atomic chemical potentials, the formation energetics of intrinsic vacancy defects in Ca3SnO are evaluated for various growth conditions. Our results indicate that the fully charged calcium vacancies are thermodynamically stable under the permissible Sn-rich condition of stable synthesis of Ca3SnO, while tin and oxygen vacancies are found to be stable under the extreme Ca-rich condition.

  1. Terbium doped SnO2 nanoparticles as white emitters and SnO2:5Tb/Fe3O4 magnetic luminescent nanohybrids for hyperthermia application and biocompatibility with HeLa cancer cells.

    Science.gov (United States)

    Singh, Laishram Priyobarta; Singh, Ningthoujam Premananda; Srivastava, Sri Krishna

    2015-04-14

    SnO2:5Tb (SnO2 doped with 5 at% Tb(3+)) nanoparticles were synthesised by a polyol method and their luminescence properties at different annealing temperatures were studied. Characterization of nanomaterials was done by X-ray diffraction (XRD), Fourier transformation infrared spectroscopy (FTIR), transmission electron microscopy (TEM) and vibrating sample magnetometry (VSM). XRD studies indicate that the prepared nanoparticles were of tetragonal structures. Upon Tb(3+) ion incorporation into SnO2, Sn(4+) changes to Sn(2+) and, on annealing again at higher temperature, Sn(2+) changes to Sn(4+). The prepared nanoparticles were spherical in shape. Sn-O vibrations were found from the FTIR studies. In photoluminescence studies, the intensity of the emission peaks of Tb(3+) ions increases with the increase of annealing temperature, and emission spectra lie in the region of white emission in the CIE diagram. CCT calculations show that the SnO2:5Tb emission lies in cold white emission. Quantum yields up to 38% can be obtained for 900 °C annealed samples. SnO2:5Tb nanoparticles were well incorporated into the PVA polymer and such a material incorporated into the polymer can be used for display devices. The SnO2:5Tb/Fe3O4 nanohybrid was prepared and investigated for hyperthermia applications at different concentrations of the nanohybrid. This achieves a hyperthermia temperature (42 °C) under an AC magnetic field. The hybrid nanomaterial SnO2:5Tb/Fe3O4 was found to exhibit biocompatibility with HeLa cells (human cervical cancer cells) at concentrations up to 74% for 100 μg L(-1). Also, this nanohybrid shows green emission and thus it will be helpful in tracing magnetic nanoparticles through optical imaging in vivo and in vitro application.

  2. Hydrogen Production from Ethanol Steam Reforming over SnO2-K2O/Zeolite Y Catalyst

    International Nuclear Information System (INIS)

    Lee, Jun Sung; Kim, Ji Eun; Kang, Mi Sook

    2011-01-01

    The SnO 2 with a particle size of about 300 nm instead of Ni is used in this study to overcome rapid catalytic deactivation by the formation of a NiAl 2 O 4 spinal structure on the conventional Ni/γ-Al 2 O 3 catalyst and simultaneously impregnated the catalyst with potassium (K). The SnO 2 -K 2 O impregnated Zeolite Y catalyst (SnO 2 -K 2 O/ZY) exhibited significantly higher ethanol reforming reactivity that that achieved with SnO 2 100 and SnO 2 30 wt %/ZY catalysts. The main products from ethanol steam reforming (ESR) over the SnO 2 -K 2 O/ ZY catalyst were H 2 , CO 2 , and CH 4 , with no evidence of any CO molecule formation. The H 2 production and ethanol conversion were maximized at 89% and 100%, respectively, over SnO 2 30 wt %-K 2 O 3.0 wt %/ZY at 600 .deg. C for 1 h at a CH 3 CH 2 OH:H 2 O ratio of 1:1 and a gas hourly space velocity (GHSV) of 12,700 h -1 . No catalytic deactivation occurred for up to 73 h. This result is attributable to the easier and weaker of reduction of Sn components and acidities over SnO 2 -K 2 O/ZY catalyst, respectively, than those of Ni/γ-Al 2 O 3 catalysts

  3. Compensation and persistent photocapacitance in homoepitaxial Sn-doped β-Ga2O3

    Science.gov (United States)

    Polyakov, A. Y.; Smirnov, N. B.; Shchemerov, I. V.; Gogova, D.; Tarelkin, S. A.; Pearton, S. J.

    2018-03-01

    The electrical properties of epitaxial β-Ga2O3 doped with Sn (1016-9 × 1018 cm-3) and grown by metalorganic chemical vapor deposition on semi-insulating β-Ga2O3 substrates are reported. Shallow donors attributable to Sn were observed only in a narrow region near the film/substrate interface and with a much lower concentration than the total Sn density. For heavily Sn doped films (Sn concentration, 9 × 1018 cm-3), the electrical properties in the top portion of the layer were determined by deep centers with a level at Ec-0.21 eV not described previously. In more lightly doped layers, the Ec-0.21 eV centers and deeper traps at Ec-0.8 eV were present, with the latter pinning the Fermi level. Low temperature photocapacitance and capacitance voltage measurements of illuminated samples indicated the presence of high densities (1017-1018 cm-3) of deep acceptors with an optical ionization threshold of 2.3 eV. Optical deep level transient spectroscopy (ODLTS) and photoinduced current transient spectroscopy (PICTS) detected electron traps at Ec-0.8 eV and Ec-1.1 eV. For lightly doped layers, the compensation of film conductivity was mostly provided by the Ec-2.3 eV acceptors. For heavily Sn doped films, deep acceptor centers possibly related to Ga vacancies were significant. The photocapacitance and the photocurrent caused by illumination at low temperatures were persistent, with an optical threshold of 1.9 eV and vanished only at temperatures of ˜400 K. The capture barrier for electrons causing the persistent photocapacitance effect was estimated from ODLTS and PICTS to be 0.25-0.35 eV.

  4. 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

  5. Optical and electrochemical studies of polyaniline/SnO2 fibrous nanocomposites

    International Nuclear Information System (INIS)

    Manivel, P.; Ramakrishnan, S.; Kothurkar, Nikhil K.; Balamurugan, A.; Ponpandian, N.; Mangalaraj, D.; Viswanathan, C.

    2013-01-01

    Graphical abstract: Fiber with porous like structure of PANI/SnO 2 nanocomposites were prepared by simplest in situ chemical polymerization method. The PL emission spectra revealed that the band from 404 and 436 nm which is related with oxygen vacancies. The excellent electrochemical properties of composite electrode show the specific capacitance of 173 F/g at a scan rate of 25 m V/s. Display Omitted Highlights: ► Self assembled PANI/SnO 2 nanocomposites were synthesized by simple polymerization method. ► Electrochemical behavior of PANI/SnO 2 nanocomposites electrode was analyzed by CV. ► Nanocomposites exhibit a higher specific capacitance of 173 F/g, compared with pure SnO 2 . -- Abstract: Polyaniline (PANI)/tin oxide (SnO 2 ) fibrous nanocomposites were successfully prepared by an in situ chemical polymerization method with suitable conditions. The obtained composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, photoluminescence (PL), electrical conductivity and cyclic voltammetry studies (CV). The XRD pattern of the as-prepared sample shows the presence of tetragonal SnO 2 and the crystalline structure of SnO 2 was not affected with the incorporation of PANI. The FTIR analysis confirms the uniform attachment of PANI on the surface of SnO 2 nanostructures. SEM images show a fibrous agglomerated structure of PANI/SnO 2 . The PL emission spectra revealed that the band from 404 and 436 nm which is related with oxygen vacancies. The electrochemical behavior of the PANI/SnO 2 composite electrode was evaluated in a H 2 SO 4 solution using cyclic voltammetry. The composite electrode exhibited a specific capacitance of 173 F/g at a scan rate 25 mV/s. Thus the as-prepared PANI/SnO 2 composite shows excellent electrochemical properties, suggesting that this composite is a promising material for supercapacitors.

  6. High blocking temperature in SnO{sub 2} based super-paramagnetic diluted magnetic semiconductor

    Energy Technology Data Exchange (ETDEWEB)

    Mounkachi, O., E-mail: o.mounkachi@mascir.com [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble cedex 9 (France); Salmani, E. [LMPHE, associé au CNRST (URAC 12), Faculté des Sciences, Université Mohammed V-Agdal, Rabat (Morocco); El Moussaoui, H. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Masrour, R. [Laboratory of Materials, Processes, Environment and Quality, Cady Ayyed University, National School of Applied Sciences, Safi (Morocco); Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble cedex 9 (France); Hamedoun, M. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); Ez-Zahraouy, H. [LMPHE, associé au CNRST (URAC 12), Faculté des Sciences, Université Mohammed V-Agdal, Rabat (Morocco); Hlil, E.K. [Institut Néel, CNRS et Université Joseph Fourier, BP 166, F-38042 Grenoble cedex 9 (France); Benyoussef, A. [Institute of Nanomaterials and Nanotechnology, MAScIR, Rabat (Morocco); LMPHE, associé au CNRST (URAC 12), Faculté des Sciences, Université Mohammed V-Agdal, Rabat (Morocco)

    2014-11-25

    Highlights: • Simple doping, (Sn,Fe)O{sub 2} exhibits a soft ferromagnetism at low temperature. • High blocking temperature was observed for Cu doped (Sn,Fe)O{sub 2} nanocrystalline. • Experimental results are confirmed by ab initio calculations. - Abstract: (Fe,Cu)-doped SnO{sub 2} nanocrystals was synthesized using the co-precipitation method. Magnetic Properties Measurement System (MPMS) revealed that for simple doping, Fe-doped SnO{sub 2} soft ferromagnetism at low temperature appears, while the ferromagnetic phase is stable at temperature higher than room temperature for Cu co-doping element. The ferromagnetism is significantly enhanced by the Cu addition to Fe-doped SnO{sub 2}, according to the ZFC and FC magnetizations and the hysteresis loops. The evidences for the existence of superparamagnetism are characterized and high blocking temperature super-paramagnetism in (Fe,Cu)-doped SnO{sub 2} nanocrystals was observed. Based on first-principles calculations, we have investigated electronic structures and magnetic properties of Fe-doped SnO{sub 2} and (Fe,Cu)-doped SnO{sub 2} with and without defect with LDA and LDA-SIC approximations. The results suggest that the oxygen vacancies (V{sub O}) play a critical role in the activation of ferromagnetism in Fe doped SnO{sub 2}. For (Fe,Cu)-doped SnO{sub 2} the results exhibit that Cu strongly influences on the magnetic properties of these doped systems which are in good agreement with the experimental observations. Electronic structure show that the presence of Cu promote the ferromagnetic bound magnetic polaron interaction through the carriers introduce by d (Cu)

  7. Structural anisotropy in amorphous SnO2 film probed by X-ray absorption spectroscopy

    Science.gov (United States)

    Zhu, Q.; Ma, Q.; Buchholz, D. B.; Chang, R. P. H.; Bedzyk, M. J.; Mason, T. O.

    2013-07-01

    Polarization-dependent X-ray absorption measurements reveal the existence of structural anisotropy in amorphous (a-) SnO2 film. The anisotropy is readily seen for the second neighbor interaction whose magnitude differs along three measured directions. The differences can be well accounted for by 10%-20% variation in the Debye-Waller factor. Instead of a single Gaussian distribution found in crystalline SnO2, the Sn-O bond distribution is bimodal in a-SnO2 whose separation shows a weak angular dependence. The oxygen vacancies, existing in the a-SnO2 film in the order of 1021 cm-3, distribute preferentially along the film surface direction.

  8. 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.

  9. Morphologically controlled synthesis, structural and optical properties of CeO2/SnO2 nanocomposites

    Directory of Open Access Journals (Sweden)

    S. Usharani

    2017-09-01

    Full Text Available CeO2/SnO2 nanocomposites with different dimensional nanostructures were synthesized by a wet chemical method, using various surfactants such as SDS, CTAB and Triton X-100. The prepared CeO2/SnO2 samples were analyzed by X-ray diffraction (XRD, Fourier transform infrared (FTIR, Transmission electron microscopy (TEM, UV-Diffuse Reflectance Spectroscopy (UV-DRS, and Photoluminescence (PL spectroscopy. The XRD patterns reveal the presence of a mixed phase of SnO2 and CeO2; The TEM analysis showed the mixed morphology of uniformly dispersed spherical with ellipsoidal shape in the SDS assisted CeO2/SnO2 nanocomposites; whereas the nanostructure with spherical with hexagonal shapes was observed for the Triton X-100 assisted CeO2/SnO2 nanocomposites. The one dimensional (1D nanorod like structure observed for the CTAB assisted CeO2/SnO2 nanocomposites shows CTAB acting as a face-specific capping agent to form rod-shaped micelles. The room temperature photoluminescence emission studies of the CeO2/SnO2 nanocomposites showed strong peaks in the UV region, and several peaks in the visible region, which are likely to have originated from the oxygen vacancies and are potential materials for optoelectronic device applications. The UV results showed the absorption edges shifted to a high energy region and the blue shifts that occurred in all the samples.

  10. Electrochemical and optical properties of CeO2-SnO2 and CeO2-SnO2:X (X = Li, C, Si films

    Directory of Open Access Journals (Sweden)

    Berton Marcos A.C.

    2001-01-01

    Full Text Available Thin solid films of CeO2-SnO2 (17 mol% Sn and CeO2-SnO2:X (X = Li, C and Si were prepared by the sol-gel route, using an aqueous-based process. The addition of Li, C and Si to the precursor solution leads to films with different electrochemical performances. The films were deposited by the dip-coating technique on ITO coated glass (Donnelly Glass at a speed of 10 cm/min and submitted to a final thermal treatment at 450 °C during 10 min in air. The electrochemical and optical properties of the films were determined from the cyclic voltammetry and chronoamperometry measurements using 0.1 M LiOH as supporting electrolyte. The ion storage capacity of the films was investigated using in situ spectroelectrochemical method and during the insertion/extraction process the films remained transparent. The powders were characterized by thermal analysis (DSC/TGA and X-ray diffraction.

  11. Tree-like SnO2 nanowires and optical properties

    International Nuclear Information System (INIS)

    Tao Tao; Chen Qiyuan; Hu Huiping; Chen Ying

    2011-01-01

    Research highlights: → Tree-like SnO 2 nanowires can be grown as low as 1100 deg. C by a vapour-solid process using a milled SnO 2 powder as the evaporation source. → FT-IR and PL measurements have shown that the tree-like nanostructures lead to superb physical properties. → The PL spectrum of such tree-like nanowires exhibits a strong PL peak at 548 nm. - Abstract: Tree-like SnO 2 nanowires have been grown by a vapor-solid process using a milled SnO 2 powder as the evaporation source. Phase, structural evolution and chemical composition were investigated using X-ray diffraction (XRD), X-ray spectrometry (EDS), and scanning electron microscopy (SEM). The process yields a large proportion of ultra-long rutile nanowires of 50-150 nm diameter and lengths up to several tens of micrometers. High-resolution transmission electron microscopy (HRTEM) shows that the SnO 2 nanowires are single crystals in the (1 0 1) growth direction with scattered smaller crystals or nanowires as the tree branches. The SnO 2 nanostructures were also examined using Fourier transform infra-red (FT-IR) and photoluminescence (PL) spectroscopy. A strong emission band centered at 548 nm dominated the PL spectrum of the tree-like nanowires.

  12. 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.

  13. 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.

  14. 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.

  15. Superconducting Nb{sub 3}Sn intermetallics made by electrochemical reduction of Nb{sub 2}O{sub 5}-SnO{sub 2} oxides

    Energy Technology Data Exchange (ETDEWEB)

    Glowacki, B A; Fray, D J; Yan, X-Y; Chen, G

    2003-05-01

    The article is focused on low temperature superconducting Nb{sub 3}Sn material manufactured by novel electrodeoxidizing method developed in Cambridge whereby the range of alloys and intermetallics are produced cheaply making potential superconducting wires more cost effective. The process of direct electrochemical reduction of Nb{sub 2}O{sub 5}-SnO{sub 2} mixtures and in situ formation of the Nb{sub 3}Sn is discussed in details.

  16. SnO{sub 2}/ZnO composite structure for the lithium-ion battery electrode

    Energy Technology Data Exchange (ETDEWEB)

    Ahmad, Mashkoor, E-mail: mashkoorahmad2003@yahoo.com [Beijing National Center for Electron Microscopy, The State Key Laboratory of New Ceramics and Fine Processing, Laboratory of Advanced Material, China Iron and Steel Research Institute Group, Department of Material Science and Engineering, Tsinghua University, Beijing 100084 (China); Nanomaterial Research Group, Physics Division, PINSTECH, P.O. Nilore, Islamabad (Pakistan); Yingying, Shi [Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Sun, Hongyu [Beijing National Center for Electron Microscopy, The State Key Laboratory of New Ceramics and Fine Processing, Laboratory of Advanced Material, China Iron and Steel Research Institute Group, Department of Material Science and Engineering, Tsinghua University, Beijing 100084 (China); Shen, Wanci [Laboratory of Advanced Materials, Department of Materials Science and Engineering, Tsinghua University, Beijing 100084 (China); Zhu, Jing, E-mail: jzhu@mail.tsinghua.edu.cn [Beijing National Center for Electron Microscopy, The State Key Laboratory of New Ceramics and Fine Processing, Laboratory of Advanced Material, China Iron and Steel Research Institute Group, Department of Material Science and Engineering, Tsinghua University, Beijing 100084 (China)

    2012-12-15

    In this article, SnO{sub 2}/ZnO composite structures have been synthesized by two steps hydrothermal method and investigated their lithium storage capacity as compared with pure ZnO. It has been found that these composite structures combining the large specific surface area, stability and catalytic activity of SnO{sub 2} micro-crystals, demonstrate the higher initial discharge capacity of 1540 mA h g{sup -1} with a Coulombic efficiency of 68% at a rate of 120 mA h g{sup -1} between 0.02 and 2 V and found much better than that of any previously reported ZnO based composite anodes. In addition, a significantly enhanced cycling performance, i.e., a reversible capacity of 497 mA h g{sup -1} is retained after 40 cycles. The improved lithium storage capacity and cycle life is attributed to the addition of SnO{sub 2} structure, which act as good electronic conductors and better accommodation of the large volume change during lithiation/delithiation process. - Graphical abstract: SnO{sub 2}/ZnO composite structures demonstrate the improved lithium storage capacity and cycle life as compared with pure ZnO nanostructure. Highlights: Black-Right-Pointing-Pointer Synthesis of SnO{sub 2}/ZnO composite structures by two steps hydrothermal approach. Black-Right-Pointing-Pointer Investigation of lithium storage capacity. Black-Right-Pointing-Pointer Excellent lithium storage capacity and cycle life of SnO{sub 2}/ZnO composite structures.

  17. Polar catastrophe at the MgO(100)/SnO2(110) interface

    KAUST Repository

    Albar, Arwa

    2016-11-14

    First principles calculations, based on density functional theory, are used to investigate the structural and electronic properties of the epitaxial MgO(100)/SnO2(110) interface of wide band gap insulators. Depending on the interface termination, nonmagnetic metallic and half-metallic interface states are observed. The formation of these states is explained by a polar catastrophe model for nonpolar-polar interfaces. Strong lattice distortions and buckling develop in SnO2, which influence the interface properties as the charge discontinuity is partially screened. Already a single unit cell of SnO2 is sufficient to drive the polar catastrophe scenario. © 2016 The Royal Society of Chemistry.

  18. CO oxidation catalyzed by ag nanoparticles supported on SnO/CeO2

    KAUST Repository

    Khan, Inayatali

    2015-01-01

    Ag-Sn/CeO2 catalysts were synthesized by the co-precipitation method with different Ag-Sn wt.% loadings and were tested for the oxidation of CO. The catalysts were characterized by powder X-ray diffractometry (XRD), scanning electron microscopy (SEM), high-resolution transmission electron microscopy (HRTEM), energy dispersive X-ray spectroscopy (EDS), and selected area electron diffraction (SAED) techniques. UV-Vis measurements were carried out to elucidate the ionic states of the silver particles, and the temperature-programmed reduction (TPR) technique was employed to check the reduction temperature of the catalyst supported on CeO2. There are peaks for silver crystallites in the X-ray diffraction patterns and the presence of SnO was not well evidenced by the XRD technique due to sintering inside the 3D array channels of CeO2 during the calcination process. The Ag-Sn/CeO2 (4%) catalyst was the most efficient and exhibited 100% CO oxidation at 100 °C due to small particle size and strong electronic interaction with the SnO/CeO2 support. © 2015 Sociedade Brasileira de Química.

  19. 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%.

  20. 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.

  1. Atomic Layer Deposition of Electron Selective SnOx and ZnO Films on Mixed Halide Perovskite: Compatibility and Performance.

    Science.gov (United States)

    Hultqvist, Adam; Aitola, Kerttu; Sveinbjörnsson, Kári; Saki, Zahra; Larsson, Fredrik; Törndahl, Tobias; Johansson, Erik; Boschloo, Gerrit; Edoff, Marika

    2017-09-06

    The compatibility of atomic layer deposition directly onto the mixed halide perovskite formamidinium lead iodide:methylammonium lead bromide (CH(NH 2 ) 2 , CH 3 NH 3 )Pb(I,Br) 3 (FAPbI 3 :MAPbBr 3 ) perovskite films is investigated by exposing the perovskite films to the full or partial atomic layer deposition processes for the electron selective layer candidates ZnO and SnO x . Exposing the samples to the heat, the vacuum, and even the counter reactant of H 2 O of the atomic layer deposition processes does not appear to alter the perovskite films in terms of crystallinity, but the choice of metal precursor is found to be critical. The Zn precursor Zn(C 2 H 5 ) 2 either by itself or in combination with H 2 O during the ZnO atomic layer deposition (ALD) process is found to enhance the decomposition of the bulk of the perovskite film into PbI 2 without even forming ZnO. In contrast, the Sn precursor Sn(N(CH 3 ) 2 ) 4 does not seem to degrade the bulk of the perovskite film, and conformal SnO x films can successfully be grown on top of it using atomic layer deposition. Using this SnO x film as the electron selective layer in inverted perovskite solar cells results in a lower power conversion efficiency of 3.4% than the 8.4% for the reference devices using phenyl-C 70 -butyric acid methyl ester. However, the devices with SnO x show strong hysteresis and can be pushed to an efficiency of 7.8% after biasing treatments. Still, these cells lacks both open circuit voltage and fill factor compared to the references, especially when thicker SnO x films are used. Upon further investigation, a possible cause of these losses could be that the perovskite/SnO x interface is not ideal and more specifically found to be rich in Sn, O, and halides, which is probably a result of the nucleation during the SnO x growth and which might introduce barriers or alter the band alignment for the transport of charge carriers.

  2. Microemulsion mediated synthesis of triangular shape SnO{sub 2} nanoparticles: Luminescence application

    Energy Technology Data Exchange (ETDEWEB)

    Luwang, Meitram Niraj, E-mail: mn.luwang@ncl.res.in

    2014-01-30

    The triangular prism shapes of SnO{sub 2}·xH{sub 2}O nanoparticles are prepared using microemulsion route. The effect of variation of water pool value on the formation of SnO{sub 2} nanoparticles was studied. There is the quantum size effect in absorption study of SnO{sub 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{sub 2} nanoparticles. Quenching effect increases with increase of water to surfactant ratio in luminescence. There is no significant effect in lifetime values for SnO{sub 2} nanoparticles in both microemulsion and powder form. SnO{sub 2} nanoparticles show green emission due to oxygen vacancy. SnO{sub 2} nanoparticles when doped with Eu{sup 3+} ions give the enhanced luminescence of Eu{sup 3+} due to the surface mediated energy transfer from SnO{sub 2} to Eu{sup 3+} ion.

  3. 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

  4. Enhanced Activity and Durability of Nanosized Pt-SnO2/IrO2/CNTs Catalyst for Methanol Electrooxidation.

    Science.gov (United States)

    Wang, Hongjuan; Wang, Xiaohui; Zheng, Jiadao; Peng, Feng; Yu, Hao

    2015-05-01

    Pt-SnO2/IrO2/CNTs anode catalyst for direct methanol fuel cell was designed and prepared with IrO2/CNTs as support for the subsequent immobilization of Pt and SnO2 at the same time. The structure of the catalysts and their catalytic performance in methanol electrooxidation were investigated and the roles of IrO2 and SnO2 in methanol electrooxidation were discussed as well. Results show that Pt-SnO2/IrO2/CNTs catalyst exhibits the best activity and durability for methanol electrooxidation when compared with Pt/CNTs, Pt/IrO2/CNTs and Pt-SnO2/CNTs. According to the results of electrochemical tests and physicochemical characterizations, the enhancements of Pt-SnO2/IrO2/CNTs were attributed to the special properties of IrO2 and SnO2, in which IrO2 mainly increases the methanol oxidation activity and SnO2 mainly improves the CO oxidation ability and durability. Therefore, Pt-SnO2/IrO2/CNTs exhibits excellent performance for methanol oxidation with higher electrocatalytic activity (I(f) of 1054 A g(Pt(-1)) and powerful anti-poisoning ability (the onset potential for CO oxidation of 0.3 V) and outstanding durability (the sustained time t in CP of 617 s), revealing a suitable anode catalyst for DMFCs.

  5. Surface properties and dye loading behavior of Zn2SnO4 nanoparticles hydrothermally synthesized using different mineralizers

    International Nuclear Information System (INIS)

    Annamalai, Alagappan; Eo, Yang Dam; Im, Chan; Lee, Man-Jong

    2011-01-01

    We present for the first time the influence of different mineralizers on the isoelectric point (IEP) of zinc stannate (Zn 2 SnO 4 ) nanoparticles hydrothermally prepared using three different mineralizers, viz., Na 2 CO 3 , KOH and tert-butyl amine, and the effect of the IEPs on the dye loading behavior of Zn 2 SnO 4 based photoelectrodes in dye sensitized solar cells (DSSCs). To produce highly crystalline, uniform sized Zn 2 SnO 4 nanoparticles, hydrothermal processing parameters, such as reaction temperature, time, and the mineralizers used have been critically adjusted. The structural and morphological features of the as-synthesized Zn 2 SnO 4 nanoparticles have been observed using both scanning and transmission electron microscopy. For the surface state characterization of shape- and size-controlled Zn 2 SnO 4 nanoparticles, the IEPs of Zn 2 SnO 4 surfaces were determined through zeta potential measurements. The IEPs were found to be 5.7, 7.4 and 8.1 for Zn 2 SnO 4 nanoparticles formed using Na 2 CO 3 , KOH and tert-butyl amine, respectively, suggesting that the surface properties of Zn 2 SnO 4 nanoparticles can be manipulated through the choice of the mineralizers used during the hydrothermal reaction. The amount of N719 dye loading on the surfaces of Zn 2 SnO 4 electrodes having different IEPs was also evaluated. It was revealed that the higher the IEP, the higher the dye loading amount, which means that the IEP mainly affects the dye loading at the dye-metal oxide interface. - Highlights: → The effect of various mineralizers on the isoelectric point of Zn 2 SnO 4 was discussed. → The IEP of Zn 2 SnO 4 can be modified by the choice of mineralizer. → Change in IEP affects the surface properties and the morphology of Zn 2 SnO 4 particles. → Modified surface affects the N719 dye loading behaviour of the Zn 2 SnO 4 based DSSCs.

  6. Structural, optical and magnetic properties of Cr doped SnO2 nanoparticles stabilized with polyethylene glycol

    International Nuclear Information System (INIS)

    Subramanyam, K.; Sreelekha, N.; Murali, G.; Reddy, D. Amaranatha; Vijayalakshmi, R.P.

    2014-01-01

    Pure and Cr (1, 3, 5 and 7 at%) doped SnO 2 nanoparticles were synthesized in aqueous solution by a simple chemical co-precipitation method using polyethylene glycol (PEG) as a stabilizing agent. The effect of Cr doping on the structural, optical and magnetic properties of SnO 2 nanoparticles was investigated. EDAX spectra confirmed the presence of Sn, O and Cr in near stoichiometry. XRD patterns revealed that particles of all samples were crystallized in single phase rutile type tetragonal crystal structure (P4 2 /mnm) of SnO 2 . The peak positions with Cr concentration shifted to higher 2θ values. Lattice parameters were also decreased with increasing Cr concentration. TEM studies indicated that the particle size is in the range of 8–10 nm. The optical absorption studies indicated that the absorption edge shifted towards lower wavelengths with inclusion of Cr content. FTIR spectrum displays various bands that are due to fundamental overtones of PEG and O–Sn–O entities. Further it revealed that the undoped and as well as Cr doped SnO 2 nanoparticles were capped by PEG. Magnetization measurements at room temperature revealed that all the doped samples were ferromagnetic in nature. Well defined strong room temperature ferromagnetic hysteresis loop was observed for 1% Cr doped SnO 2 nanoparticles

  7. Characterization of amorphous multilayered ZnO-SnO2 heterostructure thin films and their field effect electronic properties

    International Nuclear Information System (INIS)

    Lee, Su-Jae; Hwang, Chi-Sun; Pi, Jae-Eun; Yang, Jong-Heon; Oh, Himchan; Cho, Sung Haeng; Cho, Kyoung-Ik; Chu, Hye Yong

    2014-01-01

    Multilayered ZnO-SnO 2 heterostructure thin films were produced using pulsed laser ablation of pie-shaped ZnO-SnO 2 oxides target, and their structural and field effect electronic transport properties were investigated as a function of the thickness of the ZnO and SnO 2 layers. The films have an amorphous multilayered heterostructure composed of the periodic stacking of the ZnO and SnO 2 layers. The field effect electronic properties of amorphous multilayered ZnO-SnO 2 heterostructure thin film transistors (TFTs) are highly dependent on the thickness of the ZnO and SnO 2 layers. The highest electron mobility of 37 cm 2 /V s, a low subthreshold swing of a 0.19 V/decade, a threshold voltage of 0.13 V, and a high drain current on-to-off ratio of ∼10 10 obtained for the amorphous multilayered ZnO(1.5 nm)-SnO 2 (1.5 nm) heterostructure TFTs. These results are presumed to be due to the unique electronic structure of an amorphous multilayered ZnO-SnO 2 heterostructure film consisting of ZnO, SnO 2 , and ZnO-SnO 2 interface layers

  8. Sensing mechanism of SnO2/ZnO nanofibers for CH3OH sensors: heterojunction effects

    Science.gov (United States)

    Tang, Wei

    2017-11-01

    SnO2/ZnO composite nanofibers were synthesized by a simple electrospinning method. The prepared SnO2/ZnO gas sensors exhibited good linear and high response to methanol. The enhanced sensing behavior of SnO2/ZnO might be associated with the homotypic heterojunction effects formed in n-SnO2/n-ZnO nanograins boundaries. In addition, the possible sensing mechanisms of methanol on SnO2/ZnO surface were investigated by density functional theory in order to make the methanol adsorption and desorption process clear. Zn doped SnO2 model was adopted to approximate the SnO2/ZnO structure because of the calculation power limitations. Calculation results showed that when exposed to methanol, the methanol would react with bridge oxygen O2c , planar O3c and pre adsorbed oxygen vacancy on the lattice surface. The -CH3 and -OH of methanol molecule would both lose one H atom. The lost H atoms bonded with oxygen at the adsorption sites. The final products were HCHO and H2O. Electrons were transferred from methanol to the lattice surface to reduce the resistance of semiconductor gas sensitive materials, which is in agreement with the experimental phenomena. More adsorption models of other interfering gases, such as ethanol, formaldehyde and acetone will be built and calculated to explain the selectivity issue from the perspective of adsorption energy, transferred charge and density of states in the future work.

  9. Synthesis and characterization of binary ZnO-SnO2 (ZTO) thin films by e-beam evaporation technique

    Science.gov (United States)

    Bibi, Shagufta; Shah, A.; Mahmood, Arshad; Ali, Zahid; Raza, Qaisar; Aziz, Uzma; Haneef; Waheed, Abdul; Shah, Ziaullah

    2018-04-01

    The binary ZnO-SnO2 (ZTO) thin films with varying SnO2 concentrations (5, 10, 15, and 20 wt%) were grown on glass substrate by e-beam evaporation technique. The prepared ZTO films were annealed at 400 °C in air. These films were then characterized to investigate their structural, optical, and electrical properties as a function of SnO2 concentration. XRD analysis reveals that the crystallinity of the film decreases with the addition of SnO2 and it transforms to an amorphous structure at a composition of 40% SnO2 and 60% ZnO. Morphology of the films was examined by atomic force microscopy which points out that surface roughness of the films decreases with the increasing of SnO2 in the film. Optical properties such as optical transparency, band-gap energy, and optical constants of these films were examined by spectrophotometer and spectroscopic Ellipsometer. It was observed that the average optical transmission of mixed films improves with incorporation of SnO2. In addition, the band-gap energy of the films was determined to be in the range of 3.37-3.7 eV. Furthermore, it was found that the optical constants (n and k) decrease with the addition of SnO2. Similarly, it is observed that the electrical resistivity increases nonlinearly with the increase in SnO2 in ZnO-SnO2 thin films. However, it is noteworthy that the highest figure of merit (FOM) value, i.e., 55.87 × 10-5 Ω-1, is obtained for ZnO-SnO2 (ZTO) thin film with 40 wt% of SnO2 composition. Here, we suggest that ZnO-SnO2 (ZTO) thin film with composition of 60:40 wt% can be used as an efficient TCO film due to the improved transmission, and reduced RMS value and highest FOM value.

  10. Photocatalytic removal of NO and HCHO over nanocrystalline Zn2SnO4 microcubes for indoor air purification

    International Nuclear Information System (INIS)

    Ai Zhihui; Lee Shuncheng; Huang Yu; Ho Wingkei; Zhang Lizhi

    2010-01-01

    Nanocrystalline Zn 2 SnO 4 microcubes were hydrothermally synthesized and systematically characterized by XRD, SEM, TEM, XPS, N 2 adsorption-desorption, and UV-vis DRS analysis. The resulting Zn 2 SnO 4 microcubes with the edge size ranging from 0.8 to 1.2 μm were composed of numerous nanoparticles with size of 10-20 nm, and their optical band gap energy was estimated to be 3.25 eV from the UV-vis diffuse reflectance spectra. On degradation of nitrogen monoxide (NO) and formaldehyde (HCHO) at typical concentrations for indoor air quality, these nanocrystalline Zn 2 SnO 4 microcubes exhibited superior photocatalytic activity to the hydrothermally synthesized ZnO, SnO 2 , and Degussa TiO 2 P25, as well as C doped TiO 2 under UV-vis light irradiation. This enhanced photocatalytic activity of the nanocrystalline Zn 2 SnO 4 microcubes was attributed to their bigger surface areas, smaller particle size, special porous structures, and special electronic configuration. The nanocrystalline Zn 2 SnO 4 microcubes were chemically stable as there was no obvious deactivation during the multiple photocatalytic reactions. This work presents a promising approach for scaling-up industrial production of Zn 2 SnO 4 nanostructures and suggests that the synthesized nanocrystalline Zn 2 SnO 4 microcubes are promising photocatalysts for indoor air purification.

  11. Eosin Y-sensitized nanostructured SnO{sup 2}/TiO{sup 2} solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Tai, Weon-Pil [Institute of Advanced Materials, Inha University, Yonghyun-dong, Nam-ku, Inchon 402-751 (South Korea); Inoue, Kozo [National Institute of Advanced Industrial Science and Technology, Tosu, Saga 841-0052 (Japan)

    2003-02-01

    The photoelectrochemical behaviors of eosin Y (organic dye)-sensitized nanostructured SnO{sub 2}/TiO{sub 2} coupled and SnO{sub 2}+TiO{sub 2} composite solar cells were studied. The value of incident photon-to-current conversion efficiency (IPCE) in the coupled system was higher than the composite system. A maximum IPCE value, 63%, was reached at 525 nm wavelength in the coupled cell with 3.5-{mu}m-thick SnO{sub 2} and 7-{mu}m-thick TiO{sub 2}. The IPCE difference in the coupled and composite cells sensitized by eosin Y dye is discussed.

  12. Shape-selective synthesis of Sn(MoO4)2 nanomaterials for catalysis and supercapacitor applications.

    Science.gov (United States)

    Sakthikumar, K; Ede, Sivasankara Rao; Mishra, Soumyaranjan; Kundu, Subrata

    2016-06-07

    Size and shape-selective Sn(MoO4)2 nanomaterials have been synthesized for the first time using a simple hydrothermal route by the reaction of Sn(ii) chloride salt with sodium molybdate in CTAB micellar media under stirring at 60 °C temperature for about three hours. Needle-like and flake-like Sn(MoO4)2 nanomaterials were synthesized by optimizing the CTAB to metal salt molar ratio and by controlling other reaction parameters. The eventual diameter and length of the nanoneedles are ∼100 ± 10 nm and ∼850 ± 100 nm respectively. The average diameter of the flakes is ∼250 ± 50 nm. The synthesized Sn(MoO4)2 nanomaterials can be used in two potential applications, namely, catalytic reduction of nitroarenes and as an anodic material in electrochemical supercapacitors. From the catalysis study, it was observed that the Sn(MoO4)2 nanomaterials could act as a potential catalyst for the successful photochemical reduction of nitroarenes into their respective aminoarenes within a short reaction time. From the supercapacitor study, it was observed that the Sn(MoO4)2 nanomaterials of different shapes show different specific capacitance (Cs) values and the highest Cs value was observed for Sn(MoO4)2 nanomaterials having a flake-like morphology. The highest Cs value observed was 109 F g(-1) at a scan rate of 5 mV s(-1) for the flake-like Sn(MoO4)2 nanomaterials. The capacitor shows an excellent long cycle life along with 70% retention of the Cs value, even after 4000 consecutive cycles at a current density of 8 mA cm(-2). Other than the applications in catalysis and supercapacitors, the synthesized nanomaterials can find further applications in photoluminescence, sensor and other energy-related devices.

  13. First report of vertically aligned (Sn,Ir)O2:F solid solution nanotubes: Highly efficient and robust oxygen evolution electrocatalysts for proton exchange membrane based water electrolysis

    Science.gov (United States)

    Ghadge, Shrinath Dattatray; Patel, Prasad P.; Datta, Moni K.; Velikokhatnyi, Oleg I.; Shanthi, Pavithra M.; Kumta, Prashant N.

    2018-07-01

    One dimensional (1D) vertically aligned nanotubes (VANTs) of (Sn0.8Ir0.2)O2:10F are synthesized for the first time by a sacrificial template assisted approach. The aim is to enhance the electrocatalytic activity of F doped (Sn,Ir)O2 solid solution electrocatalyst for oxygen evolution reaction (OER) in proton exchange membrane (PEM) based water electrolysis by generating (Sn0.8Ir0.2)O2:10F nanotubes (NTs). The 1D vertical channels and the high electrochemically active surface area (ECSA ∼38.46 m2g-1) provide for facile electron transport. This results in low surface charge transfer resistance (4.2 Ω cm2), low Tafel slope (58.8 mV dec-1) and excellent electrochemical OER performance with ∼2.3 and ∼2.6 fold higher electrocatalytic activity than 2D thin films of (Sn0.8Ir0.2)O2:10F and benchmark IrO2 electrocatalysts, respectively. Furthermore, (Sn0.8Ir0.2)O2:10F NTs exhibit excellent mass activity (21.67 A g-1), specific activity (0.0056 mAcm-2) and TOF (0.016 s-1), which is ∼2-2.6 fold higher than thin film electrocatalysts at an overpotential of 270 mV, with a total mass loading of 0.3 mg cm-2. In addition, (Sn0.8Ir0.2)O2:10F NTs demonstrate remarkable electrochemical durability - comparable to thin films of (Sn0.8Ir0.2)O2:10F and pure IrO2, operated under identical testing conditions in PEM water electrolysis. These results therefore indicate promise of (Sn0.8Ir0.2)O2:10F NTs as OER electrocatalysts for efficient and sustainable hydrogen production.

  14. 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....

  15. 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

  16. Fabrication of p-type conductivity in SnO{sub 2} thin films through Ga doping

    Energy Technology Data Exchange (ETDEWEB)

    Tsay, Chien-Yie, E-mail: cytsay@fcu.edu.tw; Liang, Shan-Chien

    2015-02-15

    Highlights: • P-type Ga-doped SnO{sub 2} semiconductor films were prepared by sol-gel spin coating. • Optical bandgaps of the SnO{sub 2}:Ga films are narrower than that of the SnO{sub 2} film. • SnO{sub 2}:Ga films exhibited p-type conductivity as Ga doping content higher than 10%. • A p-n heterojunction composed of p-type SnO{sub 2}:Ga and n-type ZnO:Al was fabricated. - Abstract: P-type transparent tin oxide (SnO{sub 2}) based semiconductor thin films were deposited onto alkali-free glass substrates by a sol-gel spin-coating method using gallium (Ga) as acceptor dopant. In this study, we investigated the influence of Ga doping concentration ([Ga]/[Sn] + [Ga] = 0%, 5%, 10%, 15%, and 20%) on the structural, optical and electrical properties of SnO{sub 2} thin films. XRD analysis results showed that dried Ga-doped SnO{sub 2} (SnO{sub 2}:Ga) sol-gel films annealed in oxygen ambient at 520 °C for 1 h exhibited only the tetragonal rutile phase. The average optical transmittance of as-prepared thin film samples was higher than 87.0% in the visible light region; the optical band gap energy slightly decreased from 3.92 eV to 3.83 eV with increases in Ga doping content. Hall effect measurement showed that the nature of conductivity of SnO{sub 2}:Ga thin films changed from n-type to p-type when the Ga doping level was 10%, and when it was at 15%, Ga-doped SnO{sub 2} thin films exhibited the highest mean hole concentration of 1.70 × 10{sup 18} cm{sup -3}. Furthermore, a transparent p-SnO{sub 2}:Ga (Ga doping level of 15%)/n-ZnO:Al (Al doping level of 2%) heterojunction was fabricated on alkali-free glass. The I-V curve measurement for the p-n heterojunction diode showed a typical rectifying characteristic with a forward turn-on voltage of 0.65 V.

  17. Enhancing Performance of SnO2-Based Dye-Sensitized Solar Cells Using ZnO Passivation Layer

    Directory of Open Access Journals (Sweden)

    W. M. N. M. B. Wanninayake

    2016-01-01

    Full Text Available Although liquid electrolyte based dye-sensitized solar cells (DSCs have shown higher photovoltaic performance in their class, they still suffer from some practical limitations such as solvent evaporation, leakage, and sealing imperfections. These problems can be circumvented to a certain extent by replacing the liquid electrolytes with quasi-solid-state electrolytes. Even though SnO2 shows high election mobility when compared to the semiconductor material commonly used in DSCs, the cell performance of SnO2-based DSCs is considerably low due to high electron recombination. This recombination effect can be reduced through the use of ultrathin coating layer of ZnO on SnO2 nanoparticles surface. ZnO-based DSCs also showed lower performance due to its amphoteric nature which help dissolve in slightly acidic dye solution. In this study, the effect of the composite SnO2/ZnO system was investigated. SnO2/ZnO composite DSCs showed 100% and 38% increase of efficiency compared to the pure SnO2-based and ZnO-based devices, respectively, with the gel electrolyte consisting of LiI salt.

  18. Sunlight assisted photocatalytic degradation of Indigo Carmine using eco-friendly synthesized CdSnO3

    Directory of Open Access Journals (Sweden)

    Ashok V. Borhade

    2016-03-01

    Full Text Available In the present study I have developed an eco-friendly mechanochemical solid state method with green chemistry approach for the synthesis of CdSnO3. The photocatalyst was characterized to carry out physicochemical characterization by various analytical techniques like, Fourier Transform Infrared (FT-IR, Ultraviolet diffused reflectance Spectroscopy (UV-DRS, X-ray Diffraction (XRD, Scanning Electron Microscopy (SEM, Tunnelling Electron Microscopy (TEM and Brunauer–Emmett– Teller (BET surface area. The synthesized CdSnO3 particles had an average size of 105 nm with band gap 3.17 eV. The surface area by BET isotherm method highlight for the synthesized photocatalyst (SBET is 54.45 m2/g, with pore volume (Vp is 0.021 cc/g, and pore diameter (Dp is 24.85 Aº. Photocatalytic activity of CdSnO3 was demonstrated by degradation of Indigo carmine dye under influence of sunlight in aqueous solution

  19. Electrochemical performance of SnO{sub 2}/modified graphite composite material as anode of lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Hong-Qiang [Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemical and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004 (China); Hubei Key Laboratory for Processing and Application of Catalytic Materials, Huanggang Normal University, Huanggang 438000 (China); Yang, Guan-Hua; Huang, You-Guo; Zhang, Xiao-Hui; Yan, Zhi-Xiong [Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemical and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004 (China); Li, Qing-Yu, E-mail: liqingyu62@126.com [Guangxi Key Laboratory of Low Carbon Energy Materials, School of Chemical and Pharmaceutical Sciences, Guangxi Normal University, Guilin 541004 (China)

    2015-11-01

    In this report, we synthesized SnO{sub 2}/modified graphite anode composite material by a simple reflux method using SnCl{sub 4}·5H{sub 2}O as tin source and modified graphite as carbon source. The as-obtained composite was investigated with the help of X-ray diffraction (XRD), scanning electron microscopy (SEM) and galvanostatic cycling tests. The results show that the composite has a wave-shaped fold structure and the SnO{sub 2} nanoparticles on it have an average size of about 50 nm. Compared to pure modified graphite, the SnO{sub 2}/modified graphite exhibits a better electrochemical performance with a reversible specific capacity of 581.7 mAh g{sup −1} after 80 cycles, owing to high mechanical stress and elasticity of modified graphite could hinder the volume effect of SnO{sub 2} nanoparticles during the Li{sup +} insertion/extraction process. All these favourable characters reveal that the composite is a great potential anode material in high-performance lithium ion batteries. - Highlights: • A simple synthetic method of SnO{sub 2}/modified graphite composite as anode. • The as-prepared composite with layered structure alleviates the huge reunion of SnO{sub 2}. • The composite exhibits a good capacity retention rate of 85.8% after 25 cycles.

  20. 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

  1. Acetylcholinesterase biosensor based on SnO2 nanoparticles-carboxylic graphene-nafion modified electrode for detection of pesticides.

    Science.gov (United States)

    Zhou, Qing; Yang, Long; Wang, Guangcan; Yang, Yun

    2013-11-15

    A sensitive amperometric acetylcholinesterase (AChE) biosensor, based on SnO2 nanoparticles (SnO2 NPs), carboxylic graphene (CGR) and nafion (NF) modified glassy carbon electrode (GCE) for the detection of methyl parathion and carbofuran has been developed. The nanocomposites of SnO2 NPs and CGR was synthesized and characterized by scanning electron microscopy (SEM), X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR), respectively. Chitosan (CS) was used to immobilize AChE on SnO2 NPs-CGR-NF/GCE and to improve electronic transmission between AChE and SnO2 NPs-CGR-NF/GCE. NF was used as the protective membrane for the AChE biosensor. The SnO2 NPs-CGR-NF nanocomposites with excellent conductivity, catalysis and biocompatibility offered an extremely hydrophilic surface for AChE adhesion. The AChE biosensor showed favorable affinity to acetylthiocholine chloride (ATCl) and could catalyze the hydrolysis of ATCl with an apparent Michaelis-Menten constant value of 131 μM. The biosensor detected methyl parathion in the linear range from 10(-13) to 10(-10)M and from 10(-10) to 10(-8)M. The biosensor detected carbofuran in the linear range from 10(-12) to 10(-10)M and from 10(-10) to 10(-8)M. The detection limits of methyl parathion and carbofuran were 5 × 10(-14)M and 5 × 10(-13)M, respectively. The biosensor exhibited low applied potential, high sensitivity and acceptable stability, thus providing a promising tool for analysis of pesticides. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Effect of Indium Doping on the Sensitivity of SnO2 Gas Sensor

    International Nuclear Information System (INIS)

    Suharni; Sayono

    2009-01-01

    The dependence of sensitivity f SnO 2 gas sensors on indium concentration has been studied. Undoped and indium-doped SnO 2 gas sensors have been prepared by DC sputtering technique with following parameters i.e : electrode voltage of 3 kV, current 20 mA, vacuum pressure 1.8 × 10 -1 torr, deposition time 60 minutes and temperature of 200℃. The effect of weight variations of indium in order of 0.0370; 0.0485 and 0.0702 grams into SnO 2 thin film gas sensor for optimum result were investigated. The measurement of resistance, sensitivity and response time for various temperature for detecting of carbon monoxide (CO), Ammonia (NH 3 ) and acetone (CH 3 COCH 3 ) gas for indium doped has been done. From the analysis result shows that for indium doped 0.0702 g on the SnO 2 the resistance can be decreased from 832.0 kΩ to 3.9 kΩ and the operating temperature from 200℃ to 90℃ and improving the sensitivity from 15.92% to 40.09% and a response time from 30 seconds to 10 seconds for CO. (author)

  3. Effect of Pr6O11 doping in electrical and microstructural properties of SnO2-based varistors

    Directory of Open Access Journals (Sweden)

    Hervê Stangler Irion

    2014-04-01

    Full Text Available The influence of the dopant Pr6O11 was investigated with regard to the electrical and microstructural properties of the system (98.95-x%SnO2.1.0%CoO.0.05%Ta2O5.x%Pr6O11, where x = 0.05%, 0.10%, 0.30% and 0.50% in mol. Pr6O11 doping modifies the electrical behavior of the ceramics. The electrical parameters were: α = 8.0, EB = 319 V cm-1 and Vb = 0.66 V barrier-1 for the system without Pr6O11 and α = 17.0, EB = 853 V cm-1 and Vb = 1.15 V barrier-1 with the addition of 0.10% in mol Pr6O11. The system with 0.05% in mol Pr6O11 had the same non-linearity coefficient α as the system with 0.10% in mol. However, breakdown electrical field and voltage per barrier rates were lower (EB = 708 V cm-1 and Vb = 0.98 V barrier-1. The low rates in the breakdown electrical field enabled the varistor systems under study to be used in protection systems for low-voltage energy grids. In the case of Pr6O11 concentrations above 0.10% in mol, the presence of the dopant became deleterious to the varistor’s electrical characteristics. This effect was due to an increase in praseodymium stannate (Pr2Sn2O7 secondary phase. The crystalline phase coupled to the cassiterite (SnO2 phase was found with XRD and SEM/EDS and quantified by Rietveld’s refining method.

  4. Morphology and gas sensing properties of as-deposited and thermally treated doped thin SnO{sub x} layers

    Energy Technology Data Exchange (ETDEWEB)

    Georgieva, B; Pirov, J; Podolesheva, I [Acad. J. Malinowski Central Laboratory of Photoprocesses, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl.109, 1113 Sofia (Bulgaria); Nihtianova, D, E-mail: biliana@clf.bas.b [Central Laboratory of Mineralogy and Crystallography, Bulgarian Academy of Sciences, Acad. G. Bonchev Str., Bl.107, 1113 Sofia (Bulgaria)

    2010-04-01

    Thin layers intended for gas sensors are prepared by vacuum co-evaporation of TeO{sub 2} and Sn. The as-deposited layers consist of a nanosized oxide matrix and finely dispersed dopants (Te, Sn, TeO{sub 2} or SnTe, depending on the atomic ratio R{sub Sn/Te}). In order to improve the characteristics of the layers they are additionally doped with platinum. The gas sensing properties are strongly dependent on the atomic ratio R{sub Sn/Te}, as well as on the structure, composition and surface morphology. The as-deposited layers with R{sub Sn/Te} 0.8 are highly sensitive humidity sensors working at room temperature. Thermally treated Pt-doped layers with R{sub Sn/Te} 2.3 are promising as ethanol sensors. With the aim of obtaining more detailed knowledge about the surface morphology, structure and composition of layers sensitive to different environments, various techniques -TEM, SAED, SEM, EDS in SEM and white light interferometry (WLI), are applied. It is shown that all layers with 1.0 > R{sub Sn/Te} > 2, as-deposited and thermally treated, exhibit a columnar structure and a very smooth surface along with the nanograined matrix. The thermal treatment causes changes in the structure and composition of the layers. The ethanol-sensitive layers consist of nanosized polycrystalline phases of SnO{sub 2}, Sn{sub 2}O{sub 3}, Sn{sub 3}O{sub 4} and TeO{sub 2}. This knowledge could help us understand better the behaviour and govern the characteristics of layers obtained by co-evaporation of Sn and TeO{sub 2}.

  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. The electrical properties of n-ZnO/p-SnO heterojunction diodes

    Science.gov (United States)

    Javaid, K.; Xie, Y. F.; Luo, H.; Wang, M.; Zhang, H. L.; Gao, J. H.; Zhuge, F.; Liang, L. Y.; Cao, H. T.

    2016-09-01

    In the present work, n-type zinc oxide (ZnO) and p-type tin monoxide (SnO) based heterostructure diodes were fabricated on an indium-tin-oxide glass using the radio frequency magnetron sputtering technique. The prepared ZnO/SnO diodes exhibited a typical rectifying behavior, with a forward to reverse current ratio about 500 ± 5 at 2 V and turn on voltage around 1.6 V. The built-in voltage of the diode was extracted to be 0.5 V based on the capacitance-voltage (C-V) measurement. The valence and conduction band offsets were deliberated through the band energy diagram of ZnO/SnO heterojunction, as 1.08 eV and 0.41 eV, respectively. The potential barrier-dependent carrier transportation mechanism across the space charge region was also investigated.

  7. One-pot formation of SnO2 hollow nanospheres and α-Fe2O3@SnO2 nanorattles with large void space and their lithium storage properties

    KAUST Repository

    Chen, Jun Song

    2009-01-01

    In this work, uniform SnO2 hollow nanospheres with large void space have been synthesized by a modified facile method. The void space can be easily controlled by varying the reaction time. The formation of interior void space is based on an inside-out Ostwald ripening mechanism. More importantly, this facile one-pot process can be extended to fabricate rattle-type hollow structures using α-Fe2O3@SnO2 as an example. Furthermore, the electrochemical lithium storage properties have been investigated. It is found that α-Fe2O3@SnO 2 nanorattles manifest a much lower initial irreversible loss and higher reversible capacity compared to SnO2 hollow spheres. This interesting finding supports a general hypothesis that a synergistic effect between functional core and shell materials can lead to improved lithium storage capabilities. © The Royal Society of Chemistry 2009.

  8. Study of Sn and Mg doping effects on TiO2/Ge stack structure by combinatorial synthesis

    Science.gov (United States)

    Nagata, Takahiro; Suzuki, Yoshihisa; Yamashita, Yoshiyuki; Ogura, Atsushi; Chikyow, Toyohiro

    2018-04-01

    The effects of Sn and Mg doping of a TiO2 film on a Ge substrate were investigated to improve leakage current properties and Ge diffusion into the TiO2 film. For systematic analysis, dopant-composition-spread TiO2 samples with dopant concentrations of up to 20.0 at. % were fabricated by RF sputtering and a combinatorial method. X-ray photoelectron spectroscopy revealed that the instability of Mg doping of TiO2 at dopant concentrations above 10.5 at. %. Both Sn and Mg dopants reduced Ge diffusion into TiO2. Sn doping enhanced the crystallization of the rutile phase, which is a high-dielectric-constant phase, although the Mg-doped TiO2 film indicated an amorphous structure. Sn-doping indicated systematic leakage current reduction with increasing dopant concentration. Doping at Sn concentrations higher than 16.8 at. % improved the leakage properties (˜10-7 A/cm2 at -3.0 V) and capacitance-voltage properties of metal-insulator-semiconductor (MIS) operation. The Sn doping of TiO2 may be useful for interface control and as a dielectric material for Ge-based MIS capacitors.

  9. Spectroscopic ellipsometry characterization of ZnO:Sn thin films with various Sn composition deposited by remote-plasma reactive sputtering

    Science.gov (United States)

    Janicek, Petr; Niang, Kham M.; Mistrik, Jan; Palka, Karel; Flewitt, Andrew J.

    2017-11-01

    ZnO:Sn thin films were deposited onto thermally oxidized silicon substrates using a remote plasma reactive sputtering. Their optical constants (refractive index n and extinction coefficient k) were determined from ellipsometric data recorded over a wide spectral range (0.05-6 eV). Parametrization of ZnO:Sn complex dielectric permittivity consists of a parameterized semiconductor oscillator function describing the short wavelength absorption edge, a Drude oscillator describing free carrier absorption in near-infrared part of spectra and a Lorentz oscillator describing the long wavelength absorption edge and intra-band absorption in the ultra-violet part of the spectra. Using a Mott-Davis model, the increase in local disorder with increasing Sn doping is quantified from the short wavelength absorption edge onset. Using the Wemple-DiDomenico single oscillator model for the transparent part of the optical constants spectra, an increase in the centroid distance of the valence and conduction bands with increasing Sn doping is shown and only slight increase in intensity of the inter-band optical transition due to Sn doping occurs. The Drude model applied in the near-infrared part of the spectra revealed the free carrier concentration and mobility of ZnO:Sn. Results show that the range of transparency of prepared ZnO:Sn layers is not dramatically affected by Sn doping whereas electrical conductivity could be controlled by Sn doping. Refractive index in the transparent part is comparable with amorphous Indium Gallium Zinc Oxide allowing utilization of prepared ZnO:Sn layers as an indium-free alternative.

  10. Microscopic studies of a SnO2/α-Fe2O3 architectural nanocomposite using Moessbauer spectroscopic and magnetic measurements

    International Nuclear Information System (INIS)

    Hayashi, Naoaki; Muranaka, Shigetoshi; Yamamoto, Shinpei; Takano, Mikio; Zhang Dongfeng; Sun Lingdong; Yan Chunhua

    2008-01-01

    A SnO 2 /α-Fe 2 O 3 architectural nanocomposite, which was evidenced as SnO 2 nanorod arrays assembled on the surface of α-Fe 2 O 3 nanotubes in our previous study, was investigated microscopically by means of Moessbauer spectroscopic and magnetic measurements. It was found for the SnO 2 nanorods that Fe 3+ ions substituted slightly to Sn 0.998 Fe 0.002 O 2 . Concerning the α-Fe 2 O 3 tubes, the Morin transition, which was completely suppressed in the mother, SnO 2 -free α-Fe 2 O 3 nanotubes, was found to be recovered locally. We speculate that it takes place in the interface area as a result of structural modification needed for the connection with the SnO 2 nanorods. - Graphic abstract: 57 Fe Moessbauer spectrum of SnO 2 /α-Fe 2 O 3 architectural nanocomposite evidenced as SnO 2 nanorod arrays assembled on the surface of α-Fe 2 O 3 nanotubes. (I: Fe-doped SnO 2 nanorods, II: α-Fe 2 O 3 nanotubes) It was found for the SnO 2 nanorods that Fe 3+ ions substituted slightly to Sn 0.998 Fe 0.002 O 2

  11. Preparation of ternary Pt/Rh/SnO2 anode catalysts for use in direct ethanol fuel cells and their electrocatalytic activity for ethanol oxidation reaction

    Science.gov (United States)

    Higuchi, Eiji; Takase, Tomonori; Chiku, Masanobu; Inoue, Hiroshi

    2014-10-01

    Pt, Rh and SnO2 nanoparticle-loaded carbon black (Pt/Rh/SnO2/CB) catalysts with different contents of Pt and Rh were prepared by the modified Bönnemann method. The mean size and size distribution of Pt, Rh and SnO2 for Pt-71/Rh-4/SnO2/CB (Pt : Rh : Sn = 71 at.%: 4 at.%: 25 at.%) were 3.8 ± 0.7, 3.2 ± 0.7 and 2.6 ± 0.5 nm, respectively, indicating that Pt, Rh and SnO2 were all nanoparticles. The onset potential of ethanol oxidation current for the Pt-65/Rh-10/SnO2/CB and Pt-56/Rh-19/SnO2/CB electrodes was ca. 0.2 V vs. RHE which was ca. 0.2 V less positive than that for the Pt/CB electrode. The oxidation current at 0.6 V for the Pt/Rh/SnO2/CB electrode (ca. 2% h-1) decayed more slowly than that at the Pt/SnO2/CB electrode (ca. 5% h-1), indicating that the former was superior in durability to the latter. The main product of EOR in potentiostatic electrolysis at 0.6 V for the Pt-71/Rh-4/SnO2/CB electrode was acetic acid.

  12. Selectivity enhancement of indium-doped SnO2 gas sensors

    International Nuclear Information System (INIS)

    Salehi, A.

    2002-01-01

    Indium doping was used to enhance the selectivity of SnO 2 gas sensor. Both indium-doped and undoped SnO 2 gas sensors fabricated with different deposition techniques were investigated. The changes in the sensitivity of the sensors caused by selective gases (hydrogen and wood smoke) ranging from 500 to 3000 ppm were measured at different temperatures from 50 to 300 deg. C. The sensitivity peaks of the samples exhibit different values for selective gases with a response time of approximately 0.5 s. Thermally evaporated indium-doped SnO 2 gas sensor shows a considerable increase in the sensitivity peak of 27% in response to wood smoke, whereas it shows a sensitivity peak of 7% to hydrogen. This is in contrast to the sputter deposited indium-doped SnO 2 gas sensor, which exhibits a much lower sensitivity peak of approximately 2% to hydrogen and wood smoke compared to undoped SnO 2 gas sensors fabricated by chemical vapor deposition and spray pyrolysis. Scanning electron microscopy shows that different deposition techniques result in different porosity of the films. It is observed that the thermally evaporated indium-doped SnO 2 gas sensor shows high porosity, while the sputtered sample exhibits almost no porosity

  13. Hybrid functional calculation of electronic and phonon structure of BaSnO3

    International Nuclear Information System (INIS)

    Kim, Bog G.; Jo, J.Y.; Cheong, S.W.

    2013-01-01

    Barium stannate, BaSnO 3 (BSO), with a cubic perovskite structure, has been highlighted as a promising host material for the next generation transparent oxide electrodes. This study examined theoretically the electronic structure and phonon structure of BSO using hybrid density functional theory based on the HSE06 functional. The electronic structure results of BSO were corrected by extending the phonon calculations based on the hybrid density functional. The fundamental thermal properties were also predicted based on a hybrid functional calculation. Overall, a detailed understanding of the electronic structure, phonon modes and phonon dispersion of BSO will provide a theoretical starting-point for engineering applications of this material. - Graphical Abstract: (a) Crystal structure of BaSnO 3 . The center ball is Ba and small (red) ball on edge is oxygen and SnO 6 octahedrons are plotted as polyhedron. (b) Electronic band structure along the high symmetry point in the Brillouin zone using the HSE06 hybrid functional. (c) The phonon dispersion curve calculated using the HSE06 hybrid functional (d) Zone center lowest energy F 1u phonon mode. Highlights: ► We report the full hybrid functional calculation of not only the electronic structure but also the phonon structure for BaSnO 3 . ► The band gap calculation of HSE06 revealed an indirect gap with 2.48 eV. ► The effective mass at the conduction band minimum and valence band maximum was calculated. ► In addition, the phonon structure of BSO was calculated using the HSE06 functional. ► Finally, the heat capacity was calculated and compared with the recent experimental result.

  14. Hexagonal perovskites with cationic vacancies. 4. Ba/sub 8/Re/sub 3/Msup(V)Wvacant/sub 3/O/sub 24/ with Msup(V) = Nb, Ta - perovskite stacking polytypes of 24 L type

    Energy Technology Data Exchange (ETDEWEB)

    Kemmler-Sack, S [Tuebingen Univ. (Germany, F.R.). Inst. fuer Chemie

    1978-11-01

    The yellow perovskite stacking polytypes Ba/sub 8/Re/sub 3/NbWvacant/sub 3/O/sub 24/ and Ba/sub 8/Re/sub 3/TaWvacant/sub 3/O/sub 24/ have a rhombohedral layer structure of 24 L type with 3 formula units in the trigonal setting (Ba/sub 8/Re/sub 3/NbWvacant/sub 3/O/sub 24/: a = 5,82 A; c = 55.6 A; Ba/sub 8/Re/sub 3/TaWvacant/sub 3/O/sub 24/; a = 5,81 A; c = 55.6 A).

  15. 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.

  16. Sensing mechanism of SnO2/ZnO nanofibers for CH3OH sensors: heterojunction effects

    International Nuclear Information System (INIS)

    Tang, Wei

    2017-01-01

    SnO 2 /ZnO composite nanofibers were synthesized by a simple electrospinning method. The prepared SnO 2 /ZnO gas sensors exhibited good linear and high response to methanol. The enhanced sensing behavior of SnO 2 /ZnO might be associated with the homotypic heterojunction effects formed in n -SnO 2 / n -ZnO nanograins boundaries. In addition, the possible sensing mechanisms of methanol on SnO 2 /ZnO surface were investigated by density functional theory in order to make the methanol adsorption and desorption process clear. Zn doped SnO 2 model was adopted to approximate the SnO 2 /ZnO structure because of the calculation power limitations. Calculation results showed that when exposed to methanol, the methanol would react with bridge oxygen O 2c , planar O 3c and pre adsorbed oxygen vacancy on the lattice surface. The –CH 3 and –OH of methanol molecule would both lose one H atom. The lost H atoms bonded with oxygen at the adsorption sites. The final products were HCHO and H 2 O. Electrons were transferred from methanol to the lattice surface to reduce the resistance of semiconductor gas sensitive materials, which is in agreement with the experimental phenomena. More adsorption models of other interfering gases, such as ethanol, formaldehyde and acetone will be built and calculated to explain the selectivity issue from the perspective of adsorption energy, transferred charge and density of states in the future work. (paper)

  17. Synthesis, characterization and photocatalytic performance of SnS nanofibers and SnSe nanofibers derived from the electrospinning-made SnO{sub 2} nanofibers

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Li; Li, Dan; Dong, Xiangting; Ma, Qianli; Yu, Wensheng; Wang, Xinlu; Yu, Hui; Wang, Jinxian; Liu, Guixia, E-mail: dongxiangting888@163.com [Key Laboratory of Applied Chemistry and Nanotechnology at Universities of Jilin Province, Changchun University of Science and Technology, Changchun (China)

    2017-11-15

    SnO{sub 2} nanofibers were fabricated by calcination of the electrospun PVP/SnCl{sub 4} composite nanofibers. For the first time, SnS nanofibers and SnSe nanofibers were successfully synthesized by double crucible sulfurization and selenidation methods via inheriting the morphology of SnO{sub 2} nanofibers used as precursors, respectively. X-ray diffraction (XRD) analysis shows SnS nanofibers and SnSe nanofibers are respectively pure orthorhombic phase with space group of Pbnm and Cmcm. Scanning electron microscope (SEM) observation indicates that the diameters of SnS nanofibers and SnSe nanofibers are respectively 140.54±12.80 nm and 96.52±14.17 nm under the 95 % confidence level. The photocatalytic activities of samples were studied by using rhodamine B (Rh B) as degradation agent. When SnS or SnSe nanofibers are employed as the photocatalysts, the respective degradation rates of Rh B solution under the ultraviolet light irradiation after 200 min irradiation are 92.55 % and 92.86 %. The photocatalytic mechanism and formation process of SnS and SnSe nanofibers are also provided. More importantly, this preparation technique is of universal significance to prepare other metal chalcogenides nanofibers. (author)

  18. MgO Nanoparticle Modified Anode for Highly Efficient SnO2-Based Planar Perovskite Solar Cells.

    Science.gov (United States)

    Ma, Junjie; Yang, Guang; Qin, Minchao; Zheng, Xiaolu; Lei, Hongwei; Chen, Cong; Chen, Zhiliang; Guo, Yaxiong; Han, Hongwei; Zhao, Xingzhong; Fang, Guojia

    2017-09-01

    Reducing the energy loss and retarding the carrier recombination at the interface are crucial to improve the performance of the perovskite solar cell (PSCs). However, little is known about the recombination mechanism at the interface of anode and SnO 2 electron transfer layer (ETL). In this work, an ultrathin wide bandgap dielectric MgO nanolayer is incorporated between SnO 2 :F (FTO) electrode and SnO 2 ETL of planar PSCs, realizing enhanced electron transporting and hole blocking properties. With the use of this electrode modifier, a power conversion efficiency of 18.23% is demonstrated, an 11% increment compared with that without MgO modifier. These improvements are attributed to the better properties of MgO-modified FTO/SnO 2 as compared to FTO/SnO 2 , such as smoother surface, less FTO surface defects due to MgO passivation, and suppressed electron-hole recombinations. Also, MgO nanolayer with lower valance band minimum level played a better role in hole blocking. When FTO is replaced with Sn-doped In 2 O 3 (ITO), a higher power conversion efficiency of 18.82% is demonstrated. As a result, the device with the MgO hole-blocking layer exhibits a remarkable improvement of all J-V parameters. This work presents a new direction to improve the performance of the PSCs based on SnO 2 ETL by transparent conductive electrode surface modification.

  19. 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.

  20. 2D SnO2 Nanosheets: Synthesis, Characterization, Structures, and Excellent Sensing Performance to Ethylene Glycol

    Directory of Open Access Journals (Sweden)

    Wenjin Wan

    2018-02-01

    Full Text Available Two dimensional (2DSnO2 nanosheets were synthesized by a substrate-free hydrothermal route using sodium stannate and sodium hydroxide in a mixed solvent of absolute ethanol and deionized water at a lower temperature of 130 °C. The characterization results of the morphology, microstructure, and surface properties of the as-prepared products demonstrated that SnO2 nanosheets with a tetragonal rutile structure, were composed of oriented SnO2 nanoparticles with a diameter of 6–12 nm. The X-ray diffraction (XRD and high-resolution transmission electron microscope (FETEM results demonstrated that the dominant exposed surface of the SnO2 nanoparticles was (101, but not (110. The growth and formation was supposed to follow the oriented attachment mechanism. The SnO2 nanosheets exhibited an excellent sensing response toward ethylene glycol at a lower optimal operating voltage of 3.4 V. The response to 400 ppm ethylene glycol reaches 395 at 3.4 V. Even under the low concentration of 5, 10, and 20 ppm, the sensor exhibited a high response of 6.9, 7.8, and 12.0 to ethylene glycol, respectively. The response of the SnO2 nanosheets exhibited a linear dependence on the ethylene glycol concentration from 5 to 1000 ppm. The excellent sensing performance was attributed to the present SnO2 nanoparticles with small size close to the Debye length, the larger specific surface, the high-energy exposed facets of the (101 surface, and the synergistic effects of the SnO2 nanoparticles of the nanosheets.

  1. 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

  2. First-principles analysis of ferroelectric transition in MnSnO3 and MnTiO3 perovskites

    Science.gov (United States)

    Kang, Sung Gu

    2018-06-01

    The ferroelectric instabilities of an artificially adopted Pnma structure in low tolerance perovskites have been explored (Kang et al., 2017) [4], where an unstable A-site environment was reported to be the major driving source for the low tolerance perovskites to exhibit ferroelectric instability. This study examined the ferroelectric transition of two magnetic perovskite materials, MnSnO3 and MnTiO3, in Pnma phase. Phase transitions to the Pnma phase at elevated pressures were observed. MnSnO3, which has a lower (larger) tolerance factor (B-site cation radius), showed a higher ferroelectric mode amplitude than MnTiO3. The distribution of the bond length of Mn-O and the mean quadratic elongation (QE) of octahedra (SnO6 or TiO6) were investigated for structural analysis. However, MnTiO3 showed a larger spontaneous polarization than MnSnO3 due to high Born effective charges of titanium. This study is useful because it provides a valuable pathway to the design of promising multiferroic materials.

  3. Ethanol sensing properties and dominant sensing mechanism of NiO-decorated SnO2 nanorod sensors

    Science.gov (United States)

    Sun, Gun-Joo; Lee, Jae Kyung; Lee, Wan In; Dwivedi, Ram Prakash; Lee, Chongmu; Ko, Taegyung

    2017-05-01

    NiO-decorated SnO2 nanorods were synthesized by the thermal evaporation of Sn powders followed by the solvothermal deposition of NiO. A multi-networked p- n heterostructured nanorod sensor was fabricated by dropping the p-NiO-decorated n-SnO2 nanorods onto the interdigited electrode pattern and then annealing. The multi-networked p- n heterostructured nanorod sensor exhibited enhanced response to ethanol compared with the pristine SnO2 nanorod and NiO nanoparticle sensors. The former also exhibited a shorter sensing time for ethanol. Both sensors exhibited selectivity for ethanol over other volatile organic compounds (VOCs) such as HCHO, methanol, benzene and toluene and the decorated sensor exhibited superior selectivity to the other two sensors. In addition, the dominant sensing mechanism is discussed in detail by comparing the sensing properties and current-voltage characteristics of a p-NiO/ n-SnO2 heterostructured nanorod sensor with those of a pristine SnO2 nanorod sensor and a pristine NiO nanoparticle sensor. Of the two competing electronic mechanisms: a potential barrier-controlled carrier transport mechanism at a NiO-SnO2 p- n junction and a surface-depletio n-controlled carrier transport mechanism, the former has some contribution to the enhanced gas sensing performance of the p- n heterostructured nanorod sensor, however, its contribution is not as significant as that of the latter. [Figure not available: see fulltext.

  4. Atomic-scale observation of lithiation reaction front in nanoscale SnO2 materials

    KAUST Repository

    Nie, Anmin

    2013-07-23

    In the present work, taking advantage of aberration-corrected scanning transmission electron microscopy, we show that the dynamic lithiation process of anode materials can be revealed in an unprecedented resolution. Atomically resolved imaging of the lithiation process in SnO2 nanowires illustrated that the movement, reaction, and generation of b = [1Ì...1Ì...1] mixed dislocations leading the lithiated stripes effectively facilitated lithium-ion insertion into the crystalline interior. The geometric phase analysis and density functional theory simulations indicated that lithium ions initial preference to diffuse along the [001] direction in the {200} planes of SnO2 nanowires introduced the lattice expansion and such dislocation behaviors. At the later stages of lithiation, the Li-induced amorphization of rutile SnO2 and the formation of crystalline Sn and LixSn particles in the Li2O matrix were observed. © 2013 American Chemical Society.

  5. Atomic-scale observation of lithiation reaction front in nanoscale SnO2 materials

    KAUST Repository

    Nie, Anmin; Gan, Liyong; Cheng, Yingchun; Asayesh-Ardakani, Hasti; Li, Qianqian; Dong, Cezhou; Tao, Runzhe; Mashayek, Farzad; Wang, Hongtao; Schwingenschlö gl, Udo; Klie, Robert F.; Yassar, Reza Shahbazian

    2013-01-01

    In the present work, taking advantage of aberration-corrected scanning transmission electron microscopy, we show that the dynamic lithiation process of anode materials can be revealed in an unprecedented resolution. Atomically resolved imaging of the lithiation process in SnO2 nanowires illustrated that the movement, reaction, and generation of b = [1Ì...1Ì...1] mixed dislocations leading the lithiated stripes effectively facilitated lithium-ion insertion into the crystalline interior. The geometric phase analysis and density functional theory simulations indicated that lithium ions initial preference to diffuse along the [001] direction in the {200} planes of SnO2 nanowires introduced the lattice expansion and such dislocation behaviors. At the later stages of lithiation, the Li-induced amorphization of rutile SnO2 and the formation of crystalline Sn and LixSn particles in the Li2O matrix were observed. © 2013 American Chemical Society.

  6. Ab-initio study of the stability of the D8{sub m}-Nb{sub 5}Sn{sub 2}Ga and D8{sub m}-Ta{sub 5}SnGa{sub 2} compounds

    Energy Technology Data Exchange (ETDEWEB)

    Colinet, Catherine, E-mail: ccolinet@simap.grenoble-inp.fr [Science et Ingénierie des Matériaux et Procédés, Grenoble INP, UJF, CNRS, 38402 Saint Martin d’Hères Cedex (France); Tedenac, Jean-Claude [Institut de Chimie Moléculaire et des Matériaux I.C.G., UMR-CNRS 5253, Université Montpellier II, Place E. Bataillon, 34095 Montpellier Cedex 5 (France)

    2015-03-15

    Graphical abstract: Thermodynamic data along the sections Ta{sub 5}Sn{sub 3}–Ta{sub 5}Ga{sub 3} at low and high temperature. - Highlights: • First principles calculations were performed along sections V{sub 5}Sn{sub 3}–V{sub 5}Ga{sub 3}, Nb{sub 5}Sn{sub 3}–Nb{sub 5}Ga{sub 3}, and Ta{sub 5}Sn{sub 3}–Ta{sub 5}Ga{sub 3}. • The ternary compound D8{sub m}-Nb{sub 5}Sn{sub 2}Ga is stable. • The phase D8{sub m}-Ta{sub 5}SnGa{sub 2} is stable in the D8{sub m} structure. • In this phase, the Sn and Ga atoms share the 8h sites. - Abstract: First principles calculations have been performed in the T–Sn–Ga (T = V, Nb, Ta) systems along the section x{sub T} = 0.625. The enthalpies of formation of the binary and ternary D8{sub m}, D8{sub 1}, and D8{sub 8} structures have been calculated. In the V–Sn–Ga system, no ternary structure is stable in the section. In the Nb–Sn–Ga system, the ternary compound D8{sub m}-Nb{sub 5}Sn{sub 2}Ga is stable. In the Ta–Sn–Ga system, a combination of the ab-initio calculations and Gibbs energy calculations using the sublattice model allows the show that the phase D8{sub m}-Ta{sub 5}(Sn,Ga){sub 2}Ga with a mixed occupancy of the 8h sites of the structure by Ga and Sn atoms is stable at high temperature due to the configurational entropy. These results are in agreement with the experimental determinations previously published in the literature.

  7. Fully patterned p-channel SnO TFTs using transparent Al2O3 gate insulator and ITO as source and drain contacts

    Science.gov (United States)

    Guzmán-Caballero, D. E.; Quevedo-López, M. A.; De la Cruz, W.; Ramírez-Bon, R.

    2018-03-01

    SnO p-type was used as active layer to fabricate thin film transistors (TFTs) through photolithography and dry etching processes. The SnO p-type thin films (25 nm) were deposited by DC reactive sputtering with variable oxygen (O2) flow rate to then be annealed in air at 250 ◦C. Al2O3 gate dielectric (15 nm) was deposited by atomic layer deposition. Hall measurements showed p-type carrier concentration (N h ) of around 1 × 1018 cm-3 and Hall mobilities (μ Hall) between 0.35 and 2.64 cm2 V-1 s-1, depending on the O2 flow rate during deposition. The hole transport was dominated by variable-range hopping conduction. A change in the preferred crystalline orientation in the SnO films from (101) to (110) was associated with the increase in μ Hall. In addition, Raman vibrational modes at 110 and 209 cm-1 of polycrystalline SnO films showed certain dependence with the grain orientation. The SnO-based TFTs showed p-type behavior with low threshold voltages (V T ) and low sub threshold swing (SS) in the range from 1.76 to 3.50 V and 1.63 to 3.24 V/dec., respectively. The TFTs mobilities in the saturation regime (μ sat) were in the range of 0.12 and 1.32 cm2 V-1 s-1. The current on/off ratio (I ON/I OFF) was in the order of 102, approximately. The large values of the interface trap density (D IT) contributed to the high I OFF and the low I ON/I OFF of the TFTs.

  8. Nickel-doped (Zr0.8, Sn0.2)TiO4 for microwave and millimeter-wave applications

    International Nuclear Information System (INIS)

    Ioachim, A.; Banciu, M.G.; Toacsan, M.I.; Nedelcu, L.; Ghetu, D.; Alexandru, H.V.; Stoica, G.; Annino, G.; Cassettari, M.; Martinelli, M.

    2005-01-01

    (Zr 0.8 , Sn 0.2 )TiO 4 ternary compounds (ZST) have been prepared by conventional solid-state reaction from raw materials. The effects of such sintering parameters as sintering temperature, sintering time, and NiO addition on structural and dielectric properties were investigated. The material exhibits a dielectric constant ε r ∼36.0 and high values of the product Qf of the intrinsic quality factor Q and the frequency f from 32,170 to 50,000 at microwave frequencies. The dielectric loss tan δ values of ZST ceramics are decreased by low-level doping of NiO, while the temperature coefficient of the resonance frequency τ f takes values in the range -2 to +4 ppm/ deg. C. Investigations on whispering gallery modes revealed low dielectric loss in millimetre-wave domain. An intrinsic quality factor of 480 was measured at 115.6 GHz. Dielectric resonators and substrates of ZST material were manufactured. The dielectric properties make the ZST material very attractive to microwave and millimeter-wave applications, such as dielectric resonators, filters, planar antennas, hybrid microwave integrated circuits, etc

  9. Facile fabrication of robust TiO2@SnO2@C hollow nanobelts for outstanding lithium storage

    Science.gov (United States)

    Tian, Qinghua; Li, Lingxiangyu; Chen, Jizhang; Yang, Li; Hirano, Shin-ichi

    2018-02-01

    Elaborate fabrication of state-of-the-art nanostructure SnO2@C-based composites greatly contributes to alleviate the huge volume expansion issue of the SnO2 anodes. But the preparation processes of most of them are complicated and tedious, which is generally adverse to the development of SnO2@C-based composite anodes. Herein, a unique nanostructure of TiO2@SnO2@C hollow nanobelts (TiO2@SnO2@C HNBs), including the characteristics of one-dimensional architecture, sandwich protection, hollow structure, carbon coating, and a mechanically robust TiO2 support, has been fabricated by a facile approach for the first time. As anodes for lithium-ion batteries, the as-fabricated TiO2@SnO2@C HNBs exhibit an outstanding lithium storage performance, delivering capacity of 804.6 and 384. 5 mAh g-1 at 200 and even 1000 mA g-1 after 500 cycles, respectively. It is demonstrated that thus outstanding performance is mainly attributed to the unique nanostructure of TiO2@SnO2@C HNBs.

  10. Electrochemical oxidation of methanol on Pt/(RuxSn1-xO2 nanocatalyst

    Directory of Open Access Journals (Sweden)

    Krstajić Mila N.

    2013-01-01

    Full Text Available The Ru-doped SnO2 powder, (RuxSn1-xO2, with the Sn:Ru atomic ratio of 9:1 was synthesized and used as a support for Pt nanoparticles (30 mass% loading. The (RuxSn1-xO2 support and Pt/(RuxSn1-xO2 catalyst were characterized by X-ray diffraction, energy dispersive X-ray spectroscopy and transmission electron microscopy (TEM. (RuxSn1-xO2 was found to be two-phase material consisting of probably solid solution of RuO2 in SnO2 and pure RuO2. The average Pt particle size determined by TEM was 5.3 nm. Cyclic voltammetry of Pt/(RuxSn1-xO2 indicated good conductivity of the sup-port and displayed usual features of Pt. The results of the electrochemical oxidation of COads and methanol on Pt/(RuxSn1-xO2 were compared with those on commercial Pt/C and PtRu/C catalysts. Oxidation of COads on Pt/(RuxSn1-xO2 starts at less positive potentials than on PtRu/C and Pt/C. Potentiodynamic polarization curves and chronoamperometric curves of methanol oxidation indicated higher initial activity of Pt/(RuxSn1-xO2 catalyst compared to PtRu/C, but also a greater loss in the current density over time. Potentiodynamic stability test of the catalysts revealed that deactivation of the Pt/(RuxSn1-xO2 and Pt/C was primarily caused by the poisoning of Pt surface by the methanol oxidation residues, which mostly occurred during the first potential cycle. In the case of PtRu/C the poisoning of the surface was minor and deactivation was caused by the PtRu surface area loss. [Projekat Ministarstva nauke Republike Srbije, br. ON-172054

  11. 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

  12. Azadirachta indica (neem) leaves mediated synthesis of SnO2/NiO nanocomposite and assessment of its photocatalytic activity

    Science.gov (United States)

    Varshney, Bhaskar; Shoeb, Mohd; Siddiqui, M. J.; Azam, Ameer; Mobin, Mohammad

    2018-05-01

    SnO2/NiO nanocomposite are prepared by using a simple cost effective and ecofriendly green soft template method followed by ultrasonication treatment further by calcination at 300 °C. The resulting nanocatalysts were characterized by X-ray diffraction (XRD), UV-Visible spectroscopy and transmission electron microscopy (TEM). The SnO2-NiO photocatalyst was made of a mesoporous network of aggregated NiO and cassiterite SnO2 nanocrystallites, the size of which was estimated to be 16.68 nm and 13.17 nm, respectively, after calcination. According to UV-visible spectroscopy, the evident energy band gap value of the SnO2-NiO photocatalyst was estimated to be 3.132 eV to be compared with those of pure SnO2, that is, 3.7 eV. Moreover, the heterostructure SnO2-NiO photocatalyst showed much higher photocatalytic activities for the degradation of methylene blue than those of individual SnO2 and NiO nanomaterials. This behaviour was rationalized in terms of better charge separation and the suppression of charge recombination in the SnO2-NiO photocatalyst because of the energy difference between the conduction band edges of SnO2 and NiO as evidenced by the band alignment determination. Finally, this mesoporous SnO2-NiO heterojunction nanocatalyst was stable and could be easily recycled several times opening new avenues for potential industrial applications.

  13. 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 ...

  14. Nanocrystalline sol-gel TiO{sub 2}-SnO{sub 2} coatings: Preparation, characterization and photo-catalytic performance

    Energy Technology Data Exchange (ETDEWEB)

    Kaleji, Behzad Koozegar [Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of); Sarraf-Mamoory, Rasoul, E-mail: rsarrafm@modares.ac.ir [Department of Materials Engineering, Faculty of Engineering, Tarbiat Modares University, P.O. Box 14115-143, Tehran (Iran, Islamic Republic of)

    2012-02-15

    Highlights: Black-Right-Pointing-Pointer SnO{sub 2} additive enhanced significantly photo-catalytic properties of TiO{sub 2} based thin film for remove of organic compounds. Black-Right-Pointing-Pointer Structural and optical properties are dependent on dopant concentration. Black-Right-Pointing-Pointer TiO{sub 2}-SnO{sub 2} nanocrystalline thin film is promising for photocatalytic properties in visible light. -- Abstract: In this study, preparation of SnO{sub 2} (0-30 mol% SnO{sub 2})-TiO{sub 2} dip-coated thin films on glazed porcelain substrates via sol-gel process has been investigated. The effects of SnO{sub 2} on the structural, optical, and photo-catalytic properties of applied thin films have been studied by X-ray diffraction, Raman spectroscopy, and scanning electron microscopy. Surface topography and surface chemical state of thin films were examined by atomic force microscopy and X-ray photoelectron spectroscopy. XRD patterns showed an increase in peak intensities of the rutile crystalline phase by increasing the SnO{sub 2} content. The prepared Sn doped TiO{sub 2} photo-catalyst films showed optical absorption in the visible light area exhibited excellent photo-catalytic ability for the degradation of methylene blue under visible light irradiation. Best photo-catalytic activity of Sn doped TiO{sub 2} thin films was measured in the TiO{sub 2}-15 mol% SnO{sub 2} sample by the Sn{sup 4+} dopants presented substitution Ti{sup 4+} into the lattice of TiO{sub 2} increasing the surface oxygen vacancies and the surface hydroxyl groups.

  15. 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

  16. Properties of Sn-doped TiO2 nanotubes fabricated by anodization of co-sputtered Ti–Sn thin films

    International Nuclear Information System (INIS)

    Kyeremateng, Nana Amponsah; Hornebecq, Virginie; Knauth, Philippe; Djenizian, Thierry

    2012-01-01

    Self-organized Sn-doped TiO 2 nanotubes (nts) were fabricated for the first time, by anodization of co-sputtered Ti and Sn thin films. This nanostructured material was characterized by scanning electron microscopy, energy dispersive X-ray spectroscopy, X-ray diffraction, UV–vis spectroscopy and transmission electron microscopy. Due to their remarkable properties, Sn-doped TiO 2 nts can find potential applications in Li-ion microbatteries, photovoltaics, and catalysis. Particularly, the electrochemical performance as an anode material for Li-ion microbatteries was evaluated in Li test cells. With current density of 70 μA cm −2 (1 C) and cut-off potential of 1 V, Sn-doped TiO 2 nts showed improved performance compared to simple TiO 2 nts, and differential capacity plots revealed that the material undergoes full electrochemical reaction as a Rutile-type TiO 2 .

  17. Structural, optical and magnetic properties of Cr doped SnO{sub 2} nanoparticles stabilized with polyethylene glycol

    Energy Technology Data Exchange (ETDEWEB)

    Subramanyam, K.; Sreelekha, N. [Department of Physics, Sri Venkateswara University, Tirupati 517502 (India); Murali, G. [Department of BIN Fusion Technology and Department of Polymer-Nano Science and Technology, Chonbuk National University, Jeonju, Jeonbuk (Korea, Republic of); Reddy, D. Amaranatha [Department of Chemistry and Chemical Institute for Functional Materials, Pusan National University, Busan 609-735 (Korea, Republic of); Vijayalakshmi, R.P., E-mail: vijayaraguru@gmail.com [Department of Physics, Sri Venkateswara University, Tirupati 517502 (India)

    2014-12-01

    Pure and Cr (1, 3, 5 and 7 at%) doped SnO{sub 2} nanoparticles were synthesized in aqueous solution by a simple chemical co-precipitation method using polyethylene glycol (PEG) as a stabilizing agent. The effect of Cr doping on the structural, optical and magnetic properties of SnO{sub 2} nanoparticles was investigated. EDAX spectra confirmed the presence of Sn, O and Cr in near stoichiometry. XRD patterns revealed that particles of all samples were crystallized in single phase rutile type tetragonal crystal structure (P4{sub 2}/mnm) of SnO{sub 2}. The peak positions with Cr concentration shifted to higher 2θ values. Lattice parameters were also decreased with increasing Cr concentration. TEM studies indicated that the particle size is in the range of 8–10 nm. The optical absorption studies indicated that the absorption edge shifted towards lower wavelengths with inclusion of Cr content. FTIR spectrum displays various bands that are due to fundamental overtones of PEG and O–Sn–O entities. Further it revealed that the undoped and as well as Cr doped SnO{sub 2} nanoparticles were capped by PEG. Magnetization measurements at room temperature revealed that all the doped samples were ferromagnetic in nature. Well defined strong room temperature ferromagnetic hysteresis loop was observed for 1% Cr doped SnO{sub 2} nanoparticles.

  18. 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.

  19. 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)

  20. 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.

  1. One-pot electrospinning and gas-sensing properties of LaMnO3 perovskite/SnO2 heterojunction nanofibers

    Science.gov (United States)

    Chen, Dongdong; Yi, Jianxin

    2018-03-01

    Using nanostructured composite materials is an effective way to obtain high-performance gas sensors. This work used p-type LaMnO3 perovskite-structured semiconductor as a novel promoter for SnO2 nanofibers and studied the gas-sensing characteristics. Nanofibers of 0-2.5-mol% LaMnO3/SnO2 were synthesized via one-pot electrospinning. Compared with pristine SnO2, LaMnO3/SnO2 composite nanofibers exhibited smaller particle size (10-30 nm) and higher BET surface area. XPS revealed that oxygen surface absorption decreased with increasing LaMnO3 content. 0.3-mol% LaMnO3/SnO2 exhibited significantly enhanced ethanol sensitivity relative to pristine SnO2. A response of 20 was obtained at the optimum temperature of 260 °C for 100-ppm ethanol. Higher LaMnO3 loading led to decrease of the ethanol response. The impact of LaMnO3 loading on the sensing behavior of SnO2 nanofibers was discussed in terms of p-n heterojunction formation and changes in the microstructure and catalytic properties.

  2. Dopant activation in Sn-doped Ga{sub 2}O{sub 3} investigated by X-ray absorption spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Siah, S. C., E-mail: sincheng@alum.mit.edu; Brandt, R. E.; Jaramillo, R.; Buonassisi, T., E-mail: buonassisi@mit.edu [Massachusetts Institute of Technology, Cambridge, Massachusetts 02139 (United States); Lim, K. [SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, California 94025 (United States); Department of Materials Science and Engineering, Stanford University, Stanford, California 94305 (United States); Schelhas, L. T.; Toney, M. F. [SLAC National Accelerator Laboratory, Stanford Synchrotron Radiation Lightsource, Menlo Park, California 94025 (United States); Heinemann, M. D. [PVcomB, Helmholtz-Zentrum Berlin, 12489 Berlin (Germany); Chua, D.; Gordon, R. G. [Department of Chemistry Materials Science and Chemical Biology, Harvard University, Cambridge, Massachusetts 02138 (United States); Wright, J.; Segre, C. U. [Physics Department and CSRRI, Illinois Institute of Technology, Chicago, Illinois 60616 (United States); Perkins, J. D. [National Renewable Energy Laboratory, Golden, Colorado 80401 (United States)

    2015-12-21

    Doping activity in both beta-phase (β-) and amorphous (a-) Sn-doped gallium oxide (Ga{sub 2}O{sub 3}:Sn) is investigated by X-ray absorption spectroscopy (XAS). A single crystal of β-Ga{sub 2}O{sub 3}:Sn grown using edge-defined film-fed growth at 1725 °C is compared with amorphous Ga{sub 2}O{sub 3}:Sn films deposited at low temperature (<300 °C). Our XAS analyses indicate that activated Sn dopant atoms in conductive single crystal β-Ga{sub 2}O{sub 3}:Sn are present as Sn{sup 4+}, preferentially substituting for Ga at the octahedral site, as predicted by theoretical calculations. In contrast, inactive Sn atoms in resistive a-Ga{sub 2}O{sub 3}:Sn are present in either +2 or +4 charge states depending on growth conditions. These observations suggest the importance of growing Ga{sub 2}O{sub 3}:Sn at high temperature to obtain a crystalline phase and controlling the oxidation state of Sn during growth to achieve dopant activation.

  3. Properties of second phase (BaSnO3, Sn) added-YBCO thick films

    International Nuclear Information System (INIS)

    Ban, E.; Matsuoka, Y.

    1997-01-01

    The improvement of the critical current density J c of YBCO thick films has been attempted by adding BaSnO 3 powder and ultrafine Sn particles, whose diameter is about 2 μm and 7 x 10 -2 μm, respectively. It was found that the addition of a small amount of these particles was effective for the enhancement of J c of thick films prepared by a liquid-phase processing method. The 1 wt.% BaSnO 3 films fired at T s =1040-1060 C and the 3 wt.% Sn films (T s =1030-1060 C) showed J c values (77 K, 0 T) of about 2.1-2.4 x 10 3 Acm -2 and 3.1-3.5 x 10 3 Acm -2 , respectively, as compared to 2.0 x 10 3 Acm -2 for the undoped films. (orig.)

  4. Effects of coating process on the characteristics of Ag-SnO2 contact materials

    International Nuclear Information System (INIS)

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

    2006-01-01

    Good wettability between the SnO 2 and silver matrix can improve the electrical contact performance of Ag-SnO 2 materials. In this work, Ag was deposited onto the surface of Ti-doped SnO 2 particles using chemical plating to enhance the wettability. X-ray diffraction (XRD) and transmission electron microscopy (TEM) were used to characterize the Ag-coated SnO 2 particles. Scanning electron microscopy (SEM), conductivity tests, differential thermal analysis (DTA), and thermogravimetric analysis (TGA) were performed on the Ag-SnO 2 materials. Our results reveal that the chemical plating process can enhance the wettability between the Ti-doped SnO 2 particles and Ag matrix, and the Ag-coated SnO 2 particles are uniformly distributed in the Ag matrix. Both the thermal and electrical conductivity of the Ag-SnO 2 materials are significantly improved

  5. 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.

  6. Optical and electrochemical studies of polyaniline/SnO{sub 2} fibrous nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Manivel, P. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 046, Tamil Nadu (India); Ramakrishnan, S.; Kothurkar, Nikhil K. [Department of Chemical Engineering and Material Science, Amrita Vishwa Vidyapeetham, Coimbatore 641 112, Tamil Nadu (India); Balamurugan, A.; Ponpandian, N.; Mangalaraj, D. [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 046, Tamil Nadu (India); Viswanathan, C., E-mail: viswanathan@buc.edu.in [Department of Nanoscience and Technology, Bharathiar University, Coimbatore 641 046, Tamil Nadu (India)

    2013-02-15

    Graphical abstract: Fiber with porous like structure of PANI/SnO{sub 2} nanocomposites were prepared by simplest in situ chemical polymerization method. The PL emission spectra revealed that the band from 404 and 436 nm which is related with oxygen vacancies. The excellent electrochemical properties of composite electrode show the specific capacitance of 173 F/g at a scan rate of 25 m V/s. Display Omitted Highlights: ► Self assembled PANI/SnO{sub 2} nanocomposites were synthesized by simple polymerization method. ► Electrochemical behavior of PANI/SnO{sub 2} nanocomposites electrode was analyzed by CV. ► Nanocomposites exhibit a higher specific capacitance of 173 F/g, compared with pure SnO{sub 2}. -- Abstract: Polyaniline (PANI)/tin oxide (SnO{sub 2}) fibrous nanocomposites were successfully prepared by an in situ chemical polymerization method with suitable conditions. The obtained composites were characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy, photoluminescence (PL), electrical conductivity and cyclic voltammetry studies (CV). The XRD pattern of the as-prepared sample shows the presence of tetragonal SnO{sub 2} and the crystalline structure of SnO{sub 2} was not affected with the incorporation of PANI. The FTIR analysis confirms the uniform attachment of PANI on the surface of SnO{sub 2} nanostructures. SEM images show a fibrous agglomerated structure of PANI/SnO{sub 2}. The PL emission spectra revealed that the band from 404 and 436 nm which is related with oxygen vacancies. The electrochemical behavior of the PANI/SnO{sub 2} composite electrode was evaluated in a H{sub 2}SO{sub 4} solution using cyclic voltammetry. The composite electrode exhibited a specific capacitance of 173 F/g at a scan rate 25 mV/s. Thus the as-prepared PANI/SnO{sub 2} composite shows excellent electrochemical properties, suggesting that this composite is a promising material for supercapacitors.

  7. Synthesis and fundamental properties of stable Ph(3)SnSiH(3) and Ph(3)SnGeH(3) hydrides: model compounds for the design of Si-Ge-Sn photonic alloys.

    Science.gov (United States)

    Tice, Jesse B; Chizmeshya, Andrew V G; Groy, Thomas L; Kouvetakis, John

    2009-07-06

    The compounds Ph(3)SnSiH(3) and Ph(3)SnGeH(3) (Ph = C(6)H(5)) have been synthesized as colorless solids containing Sn-MH(3) (M = Si, Ge) moieties that are stable in air despite the presence of multiple and highly reactive Si-H and Ge-H bonds. These molecules are of interest since they represent potential model compounds for the design of new classes of IR semiconductors in the Si-Ge-Sn system. Their unexpected stability and high solubility also makes them a safe, convenient, and potentially useful delivery source of -SiH(3) and -GeH(3) ligands in molecular synthesis. The structure and composition of both compounds has been determined by chemical analysis and a range of spectroscopic methods including multinuclear NMR. Single crystal X-ray structures were determined and indicated that both compounds condense in a Z = 2 triclinic (P1) space group with lattice parameters (a = 9.7754(4) A, b = 9.8008(4) A, c = 10.4093(5) A, alpha = 73.35(10)(o), beta = 65.39(10)(o), gamma = 73.18(10)(o)) for Ph(3)SnSiH(3) and (a = 9.7927(2) A, b = 9.8005(2) A, c = 10.4224(2) A, alpha = 74.01(3)(o), beta = 65.48(3)(o), gamma = 73.43(3)(o)) for Ph(3)SnGeH(3). First principles density functional theory simulations are used to corroborate the molecular structures of Ph(3)SnSiH(3) and Ph(3)SnGeH(3), gain valuable insight into the relative stability of the two compounds, and provide correlations between the Si-Sn and Ge-Sn bonds in the molecules and those in tetrahedral Si-Ge-Sn solids.

  8. Structural, dielectric and magnetic properties of SnO{sub 2}-CuFe{sub 2}O{sub 4} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Kashif [Department of Physics, International Islamic University, Islamabad (Pakistan); Iqbal, Javed, E-mail: javed.saggu@qau.edu.pk [Laboratory of Nanoscience and Technology (LNT), Department of Physics, Qaid-i-Azam University, Islamabad (Pakistan); Jan, Tariq [Department of Physics, University of Lahore, Sargodha Campus, Sargodha (Pakistan); Wan, Dongyun [School of Materials Science and Engineering, Shanghai University, Shanghai 200444 (China); Ahmad, Naeem [Department of Physics, International Islamic University, Islamabad (Pakistan); Ahamd, Ishaq [Experimental Physics Labs, National Center for Physics, Islamabad (Pakistan); Ilyas, Syed Zafar [Department of Physics, Allama Iqbal Open University, Islamabad (Pakistan)

    2017-04-15

    The nanocomposites of (SnO{sub 2}){sub x}(CuFe{sub 2}O{sub 4}){sub (1−x)} (where x=0–100 wt%) have been successfully synthesized via two steps chemical method. XRD pattern has revealed the formation of inverse spinal phases with tetragonal crystal structure without any impurity phases for CuFe{sub 2}O{sub 4} sample. The thermodynamic solubility limit of SnO{sub 2} in CuFe{sub 2}O{sub 4} matrix has been found to be 30 wt% and above this percentage crystal phases related to SnO{sub 2} started to appear. The average particle size and shape of CuFe{sub 2}O{sub 4} nanoparticles have been strongly influenced by addition of SnO{sub 2} as depicted by TEM results. FTIR results have confirmed the existence of cation vibration bands at tetrahedral and octahedral sites along with Sn-O vibration band at higher concentrations, which also validates the formation of nanocomposites. Furthermore, the dielectric constant, tangent loss and conductivity of CuFe{sub 2}O{sub 4} nanoparticles have been found to increase up to 30 wt% addition of SnO{sub 2} and then decreases with further increase which is attributed to variations in resistivity and space charge carriers. Magnetic measurements have shown that saturation magnetization decreases from 35.68 emu/gm to 10.26 emu/gm with the addition of SnO{sub 2} content. - Highlights: • SnO{sub 2}-CuFe{sub 2}O{sub 4} nanocomposites with varying SnO{sub 2} concentrations were synthesized. • The thermodynamic solubility limit for SnO{sub 2} into CuFe{sub 2}O{sub 4} matrix by employing current method was found to be ≤30 wt%. • At higher concentrations, structural phases related to SnO{sub 2} started to appear. • FTIR results corroborated well with the XRD results. • It has been observed that the addition of SnO{sub 2} significantly influence the morphology, dielectric and magnetic properties of CuFe{sub 2}O{sub 4} nanoparticles.

  9. 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-.

  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. 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.

  12. V-groove SnO2 nanowire sensors: fabrication and Pt-nanoparticle decoration

    International Nuclear Information System (INIS)

    Sun, Gun-Joo; Choi, Sun-Woo; Jung, Sung-Hyun; Katoch, Akash; Kim, Sang Sub

    2013-01-01

    Networked SnO 2 nanowire sensors were achieved using the selective growth of SnO 2 nanowires and their tangling ability, particularly on on-chip V-groove structures, in an effort to overcome the disadvantages imposed on the conventional trench-structured SnO 2 nanowire sensors. The sensing performance of the V-groove-structured SnO 2 nanowire sensors was highly dependent on the geometrical dimension of the groove, being superior to those of their conventional trench-structured counterparts. Pt nanoparticles were decorated on the surface of the networked SnO 2 nanowires via γ-ray radiolysis to enhance the sensing performances of the V-groove sensors whose V-groove widths had been optimized. The V-groove-structured Pt-nanoparticle-decorated SnO 2 nanowire sensors exhibited outstanding and reliable sensing capabilities towards toluene and nitrogen dioxide gases, indicating their potential for use as a platform for chemical gas sensors. (paper)

  13. In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructured nanoparticles with enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Xing, Yonglei [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Que, Wenxiu, E-mail: wxque@mail.xjtu.edu.cn [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Yin, Xingtian; He, Zuoli; Liu, Xiaobin; Yang, Yawei; Shao, Jinyou [Electronic Materials Research Laboratory, International Center for Dielectric Research, Key Laboratory of the Ministry of Education, School of Electronic and Information Engineering, State Key Laboratory for Manufacturing Systems Engineering, Xi’an Jiaotong University, Xi’an 710049, Shaanxi (China); Kong, Ling Bing, E-mail: ELBKong@ntu.edu.sg [School of Materials Science and Engineering, Nanyang Technological University, Nanyang Avenue, Singapore 639798 (Singapore)

    2016-11-30

    Highlights: • Visible-light photocatalytic activities of the nanostructured In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructures were studied. • Effect of In{sub 2}O{sub 3} content on the photocatalytic activity of the In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructure was evaluated. • 0.1In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} heterostructure photocatalyst shows a superior photocatalytic activity. • Based on Mott-Schottky analysis and active species detection, a mechanism for the separation of photogenerated carriers is proposed. • The effective separation process of the photogenerated electron-hole pairs was testified by photocurrent test. - Abstract: In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7} composite photocatalysts with various contents of cubic In{sub 2}O{sub 3} nanoparticles were fabricated by using impregnation method. A thriving modification of Bi{sub 2}Sn{sub 2}O{sub 7} by an introduction of In{sub 2}O{sub 3} was confirmed by using X-ray diffraction, UV–vis diffuse reflectance spectrometry, transmission electron microscopy, high-resolution transmission electron microscopy and X-ray photoelectron spectroscopy. The samples composed of hybrids of In{sub 2}O{sub 3} and Bi{sub 2}Sn{sub 2}O{sub 7} exhibited a much higher photocatalytic activity for the degradation of Rhodamine B under visible light, as compared with pure In{sub 2}O{sub 3} and Bi{sub 2}Sn{sub 2}O{sub 7} nanoparticles. Optimized composition of the composite photocatalysts was 0.1In{sub 2}O{sub 3}/Bi{sub 2}Sn{sub 2}O{sub 7}, which shows a rate constant higher than those of pure In{sub 2}O{sub 3} and Bi{sub 2}Sn{sub 2}O{sub 7} by 4.06 and 3.21 times, respectively. Based on Mott-Schottky analysis and active species detection, the photoexcited electrons in the conduction band of In{sub 2}O{sub 3} and the holes in the valence band of Bi{sub 2}Sn{sub 2}O{sub 7} participated in reduction and oxidation reactions, respectively. Hence, ·OH, ·O{sub 2}{sup −} and h

  14. Mesoporous PtSnO2/C Catalyst with Enhanced Catalytic Activity for Ethanol Electro-oxidation

    Directory of Open Access Journals (Sweden)

    Siyu Chen

    2018-01-01

    Full Text Available In this paper, we report the synthesis, characterization, and electrochemical evaluation of a mesoporous PtSnO2/C catalyst, called PtSnO2(M/C, with a nominal Pt : Sn ratio of 3 : 1. Brunauer–Emmett–Teller and transmission electron microscopy characterizations showed the obvious mesoporous structure of SnO2 in PtSnO2(M/C catalyst. X-ray photoelectron spectroscopy analysis exhibited the interaction between Pt and mesoporous SnO2. Compared with Pt/C and commercial PtSnO2/C catalysts, PtSnO2(M/C catalyst has a lower active site, but higher catalytic activity for ethanol electro-oxidation reaction (EOR. The enhanced activity could be attributed to Pt nanoparticles deposited on mesoporous SnO2 that could decrease the amount of poisonous intermediates produced during EOR by the interaction between Pt and mesoporous SnO2.

  15. Origin of room temperature ferromagnetism in SnO{sub 2} films

    Energy Technology Data Exchange (ETDEWEB)

    Li, Jing [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); College of Materials Science and Engineering, China Jiliang University, Hangzhou 310018 (China); National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Bai, Guohua; Jiang, Yinzhu [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Du, Youwei [National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Wu, Chen, E-mail: chen_wu@zju.edu.cn [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China); Yan, Mi, E-mail: mse_yanmi@zju.edu.cn [School of Materials Science and Engineering, State Key Laboratory of Silicon Materials, Zhejiang University, Hangzhou 310027 (China)

    2017-03-15

    SnO{sub 2} films exhibiting room temperature ferromagnetism (RTFM) have been prepared on Si (001) by pulsed laser deposition. The saturation magnetization (M{sub s}) of the films experiences a decreasing trend followed by increasing with the growth temperature increased from RT to 400 ℃. The growth temperature affects both the concentration and the location of the oxygen vacancies as the origin of the RTFM. With lower growth temperatures (<300 ℃), more oxygen vacancies exist in the inner film for the samples with less crystallinity, resulting in enhanced magnetism. Higher deposition temperature leads to less oxygen vacancies in the inner film but more oxygen defects at the film surface, which is also beneficial to achieve greater magnetism. Various oxygen pressures during growth and post-annealing have also been used to confirm the role of oxygen vacancies. The study demonstrates that the surface oxygen defects and the positively charged monovalent O vacancies (V{sub O}{sup +}) in the inner film are the origin of the magnetism in SnO{sub 2} films. - Highlights: • SnO{sub 2} films exhibiting room temperature ferromagnetism (RTFM) have been prepared on Si (001) by pulsed laser deposition. • Growth temperature, oxygen pressure and annealing affect the growth of SnO{sub 2} films. • Both the concentration and location of the oxygen vacancies play critical roles in the magnetization.

  16. Electrochemical energy storage behavior of Sn/SnO2 double phase nanocomposite anodes produced on the multiwalled carbon nanotube buckypapers for lithium-ion batteries

    Science.gov (United States)

    Alaf, Mirac; Akbulut, Hatem

    2014-02-01

    Recent development of electrode materials for Li-ion batteries is driven mainly by hybrid nanocomposite structures consisting of Li storage compounds and CNTs. In this study, tin/tinoxide (Sn/SnO2) films and tin/tinoxide/multi walled carbon nanotube (Sn/SnO2/MWCNT) nanocomposites are produced by a two steps process; thermal evaporation and subsequent plasma oxidation as anode materials for Li-ion batteries. The physical, structural, and electrochemical behaviors of the nanocomposite electrodes containing MWCNTs are discussed. The ratio between metallic tin (Sn) and tinoxide (SnO2) is controlled with plasma oxidation time and effects of the ratio are investigated on the structural and electrochemical properties. The greatly enhanced electrochemical performance is mainly due to the morphological stability and reduced diffusion resistance, which are induced by MWCNT core and deposited Sn/SnO2 double phase shell. The outstanding long-term cycling stability is a result of the two layers Sn and SnO2 phases on MWCNTs. The nanoscale Sn/SnO2/MWCNT network provides good electrical conductivity, and the creation of open spaces that buffer a large volume change during the Li-alloying/de-alloying reaction.

  17. 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.

  18. Nitrogen-Doped Carbon-Encapsulated SnO2@Sn Nanoparticles Uniformly Grafted on Three-Dimensional Graphene-like Networks as Anode for High-Performance Lithium-Ion Batteries.

    Science.gov (United States)

    Li, Yunyong; Zhang, Haiyan; Chen, Yiming; Shi, Zhicong; Cao, Xiaoguo; Guo, Zaiping; Shen, Pei Kang

    2016-01-13

    A peculiar nanostructure consisting of nitrogen-doped, carbon-encapsulated (N-C) SnO2@Sn nanoparticles grafted on three-dimensional (3D) graphene-like networks (designated as N-C@SnO2@Sn/3D-GNs) has been fabricated via a low-cost and scalable method, namely an in situ hydrolysis of Sn salts and immobilization of SnO2 nanoparticles on the surface of 3D-GNs, followed by an in situ polymerization of dopamine on the surface of the SnO2/3D-GNs, and finally a carbonization. In the composites, three-layer core-shell N-C@SnO2@Sn nanoparticles were uniformly grafted onto the surfaces of 3D-GNs, which promotes highly efficient insertion/extraction of Li(+). In addition, the outermost N-C layer with graphene-like structure of the N-C@SnO2@Sn nanoparticles can effectively buffer the large volume changes, enhance electronic conductivity, and prevent SnO2/Sn aggregation and pulverization during discharge/charge. The middle SnO2 layer can be changed into active Sn and nano-Li2O during discharge, as described by SnO2 + Li(+) → Sn + Li2O, whereas the thus-formed nano-Li2O can provide a facile environment for the alloying process and facilitate good cycling behavior, so as to further improve the cycling performance of the composite. The inner Sn layer with large theoretical capacity can guarantee high lithium storage in the composite. The 3D-GNs, with high electrical conductivity (1.50 × 10(3) S m(-1)), large surface area (1143 m(2) g(-1)), and high mechanical flexibility, tightly pin the core-shell structure of the N-C@SnO2@Sn nanoparticles and thus lead to remarkably enhanced electrical conductivity and structural integrity of the overall electrode. Consequently, this novel hybrid anode exhibits highly stable capacity of up to 901 mAh g(-1), with ∼89.3% capacity retention after 200 cycles at 0.1 A g(-1) and superior high rate performance, as well as a long lifetime of 500 cycles with 84.0% retention at 1.0 A g(-1). Importantly, this unique hybrid design is expected to be

  19. Enhancement of field emission and photoluminescence properties of graphene-SnO2 composite nanostructures.

    Science.gov (United States)

    Ding, Jijun; Yan, Xingbin; Li, Jun; Shen, Baoshou; Yang, Juan; Chen, Jiangtao; Xue, Qunji

    2011-11-01

    In this study, the SnO(2) nanostructures and graphene-SnO(2) (G-SnO(2)) composite nanostructures were prepared on n-Si (100) substrates by electrophoretic deposition and magnetron sputtering techniques. The field emission of SnO(2) nanostructures is improved largely by depositing graphene buffer layer, and the field emission of G-SnO(2) composite nanostructures can also further be improved by decreasing sputtering time of Sn nanoparticles to 5 min. The photoluminescence (PL) spectra of the SnO(2) nanostructures revealed multipeaks, which are consistent with previous reports except for a new peak at 422 nm. Intensity of six emission peaks increased after depositing graphene buffer layer. Our results indicated that graphene can also be used as buffer layer acting as interface modification to simultaneity improve the field emission and PL properties of SnO(2) nanostructures effectively.

  20. Low-temperature processed SnO{sub 2} compact layer for efficient mesostructure perovskite solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Jinxia; Xiong, Qiu; Feng, Bingjie; Xu, Yang; Zhang, Jun; Wang, Hao, E-mail: nanoguy@126.com

    2017-01-01

    Highlights: • Low-temperature processed 70 nm cl-SnO{sub 2} device exhibits maximum PCE. • Champion PSC after SnCl{sub 4} treatment acquires PCE of 15.07%. • Cl-SnO{sub 2} PSC via SnCl{sub 4} treatment exhibits superior stability to cl-TiO{sub 2} based PSC. - Abstract: SnO{sub 2} nanoparticle film has been synthesized via low- temperature (∼180 °C) solution-processing and proposed as compact layer in mesostructure perovskite-type solar cell (PSC). Low-temperature processed SnO{sub 2} compact layer (cl-SnO{sub 2}) brings perfect crystal-lattice and band-gap matching between electron selective layer and FTO substrate and close interface-contact between cl-SnO{sub 2} and mesoporous TiO{sub 2} layer (mp-TiO{sub 2}), which contributes to suppressing carrier recombination and optimizing device performance. In varied thickness cells, 70 nm cl-SnO{sub 2} device exhibits maximum power conversion efficiency (PCE). In order to further restrain photoelectron recombination and improve the photovoltaic performance, the surface modification of cl-SnO{sub 2} by SnCl{sub 4} aqueous solution has been carried out. The recombination behavior in the cell interior is greatly retarded via SnCl{sub 4} treatment and champion PSC after SnCl{sub 4} treatment has acquire PCE of 15.07%, which is higher than PCE of cl-TiO{sub 2} based PSC fabricated with same mp-TiO{sub 2} and perovskite procedures (13.3%). The stability of cl-SnO{sub 2} PSC via SnCl{sub 4} treatment has also been measured and its PCE reduces to 13.0% after 2 weeks in air.

  1. Optically stimulated luminescence in x-ray irradiated xSnO-(25-x)SrO-75B2O3 glass

    Science.gov (United States)

    Nanto, H.; Nakagawa, R.; Takei, Y.; Hirasawa, K.; Miyamoto, Y.; Masai, H.; Kurobori, T.; Yanagida, T.; Fujimoto, Y.

    2015-06-01

    An intense optically stimulated luminescence (OSL) was observed, for the first time, in x-ray irradiated xSnO-(25-x)SrO-75B2O3 glass. It was found that the peak wavelength of OSL emission spectrum and its stimulation spectrum is about 400 nm and 600 nm, respectively. The OSL intensity is depended on the SnO contents (x=0.05-1.5) and the most intense OSL was observed in 1.0 mol% SnO doped glass. It was found that the OSL intensity is increased with increasing x-ray absorbed dose. Fairly good fading characteristics were observed in the x-ray irradiated glass, showing that this glass is useful as a candidate for OSL sensor materials for ionizing radiation monitoring.

  2. Effect of the cations distribution on the magnetic properties of SnFe{sub 2}O{sub 4}: First-principles study

    Energy Technology Data Exchange (ETDEWEB)

    Lamouri, R.; Tadout, M. [Materials and Nanomaterials Center, MAScIR Foundation, Rabat Design Center, Rue Mohamed Al Jazouli – Madinat Al Irfane, Rabat 10 100 (Morocco); LaMCScI (ex LMPHE), B.P. 1014, Faculty of Science-Mohammed V University, Rabat (Morocco); Hamedoun, M. [Materials and Nanomaterials Center, MAScIR Foundation, Rabat Design Center, Rue Mohamed Al Jazouli – Madinat Al Irfane, Rabat 10 100 (Morocco); Benyoussef, A. [Materials and Nanomaterials Center, MAScIR Foundation, Rabat Design Center, Rue Mohamed Al Jazouli – Madinat Al Irfane, Rabat 10 100 (Morocco); LaMCScI (ex LMPHE), B.P. 1014, Faculty of Science-Mohammed V University, Rabat (Morocco); Hassan II Academy of Science and Technology, Rabat (Morocco); Ez-zahraouy, H.; Benaissa, M. [LaMCScI (ex LMPHE), B.P. 1014, Faculty of Science-Mohammed V University, Rabat (Morocco); Mounkachi, O., E-mail: o.mounkachi@mascir.com [Materials and Nanomaterials Center, MAScIR Foundation, Rabat Design Center, Rue Mohamed Al Jazouli – Madinat Al Irfane, Rabat 10 100 (Morocco)

    2017-08-15

    Highlights: • SnFe{sub 2}O{sub 4} a new half-metal spinel oxides for spintronic application. • The most stable normal spinel structures are identified for SnFe{sub 2}O{sub 4}. • Spin-polarized calculations give a half-metallic character for SnFe{sub 2}O{sub 4}. - Abstract: In this work, a study of the electronic and magnetic properties of SnFe{sub 2}O{sub 4} spinel ferrite for different case of octahedral and tetrahedral distribution was carried out by using the Full Potential Linearized Plane Wave (FP-LAPW) method in density functional theory (DFT) implemented in the WIEN2K package, with the generalized gradient (GGA) and Tran-Blaha modified Becke-Johnson approximations for the exchange and correlation functional. Our spin-polarized calculations based on mBJ correction show a half metallic behavior for SnFe{sub 2}O{sub 4} which confirm the usefulness of SnFe{sub 2}O{sub 4} in spintronic application. From the magnetic properties calculations, it is found that the magnetic moment per formula unit is 8.0327 µ{sub β}, 0.000015 µ{sub β} and 3.99µ{sub β} in SnFe{sub 2}O{sub 4} 100% normal, 100% inverse and 50% inverse, respectively.

  3. SnO{sub 2} foam grain-shaped nanoparticles: Synthesis, characterization and UVA light induced photocatalysis

    Energy Technology Data Exchange (ETDEWEB)

    Abdelkader, Elaziouti, E-mail: elaziouti_a@yahoo.com [Laboratory of Electronic Microscope and Materials Science, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria); Nadjia, Laouedj, E-mail: nlaouedj@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria); Naceur, Benhadria, E-mail: nacer1974@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria); Noureddine, Bettahar, E-mail: nbettahar2001@yahoo.fr [Laboratory of Inorganic Materials Chemistry and Application, University of Science and Technology of Oran (USTO M. B), BP 1505 El M' naouar, 31000 Oran (Algeria)

    2016-09-15

    Cassiterite (tin oxide; SnO{sub 2}) nanoparticles (NPs), has been successfully synthesized via a sol-gel method. The obtained compounds are subsequently calcined at 80, 450 and 650 °C for 4 h and are assigned as SnO{sub 2}-80, SnO{sub 2}-450 NPs and SnO{sub 2}-650 NPs, respectively. All prepared samples were characterized using thermogravimetric analysis coupled with mass spectroscopy (TG-SM), X-ray diffraction (XRD), scanning electron microscope (SEM) and UV–vis diffuse reflectance spectroscopy (UV–vis DRS). The XRD results confirmed the aggregated cassiterite SnO{sub 2} nanoparticles (NPs) with a size ranging from 13 to 23 nm. The absorption edge of the SnO{sub 2} NPs samples calcined at higher temperatures showed 25 nm (SnO{sub 2}-450 NPs) and 10 nm (SnO{sub 2}-650 NPs) red shifted compared with that of commercial SnO{sub 2}-com NPs sample. The photodegradation efficiency of SnO{sub 2} NPs was investigated using Congo red (CR) dye, as model organic pollutant. The effect of environmental factors (e.g., reaction time and calcination temperature) on the photocatalysis process of CR on SnO{sub 2} NPs was investigated in photocatalysis process under UVA light irradiation. We found that the SnO{sub 2}-650 NPs with 23 nm particle size and about 3.49 eV band gap was higher than that of the SnO{sub 2}-450 as well as the commercial SnO{sub 2}-com NPs. Pseudo-first-order kinetic model gave the best fit, with highest correlation coefficients (R{sup 2} ≥ 0.95). On the basis of the energy band diagram positions, the enhanced photodegradation efficiency SnO{sub 2} NPs catalyst could be proceeded via direct reactions with (O{sub 2}·{sup -} and ·OH), as active oxidative species involved in the photocatalysis process of CR dye under UVA-light irradiation. - Highlights: • SnO{sub 2} NPs photocatalysts were synthesized using a facile sol–gel route. • As-prepared SnO{sub 2} NPs were characterized by XRD, SEM and UV–vis-DRS techniques. • Noticeably UVA

  4. Incorporation of graphene into SnO{sub 2} photoanodes for dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Batmunkh, Munkhbayar [School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005 (Australia); Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Bedford Park, Adelaide, South Australia 5042 (Australia); Dadkhah, Mahnaz; Shearer, Cameron J. [Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Bedford Park, Adelaide, South Australia 5042 (Australia); Biggs, Mark J. [School of Chemical Engineering, The University of Adelaide, Adelaide, South Australia 5005 (Australia); School of Science, Loughborough University, Loughborough, Leicestershire LE11 3TU (United Kingdom); Shapter, Joseph G., E-mail: joe.shapter@flinders.edu.au [Centre for Nanoscale Science and Technology, School of Chemical and Physical Sciences, Flinders University, Bedford Park, Adelaide, South Australia 5042 (Australia)

    2016-11-30

    Graphical abstract: Incorporation of a graphene structure into SnO{sub 2} dye-sensitized solar cell photoanode films has been demonstrated for the first time. The use of graphene in the SnO{sub 2} has been found to be a promising strategy to address many problems of photovoltaic cells based on SnO{sub 2} photoanodes. - Highlights: • SnO{sub 2}-reduced graphene oxide (RGO) hybrid is prepared using a microwave technique. • The first SnO{sub 2}-RGO photoanode based DSSC is fabricated. • Use of RGO addresses the major shortcoming of SnO{sub 2} when employed as a DSSC photoanode. • RGO significantly improved the electron transport rate within the DSSC devices. • Incorporation of RGO into the SnO{sub 2} photoanode enhanced the DSSC efficiency by 91.5%. - Abstract: In dye-sensitized solar cell (DSSC) photoanodes, tin dioxide (SnO{sub 2}) structures present a promising alternative semiconducting oxide to the conventional titania (TiO{sub 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{sub 2} and reduced graphene oxide (SnO{sub 2}-RGO) was synthesized via a microwave-assisted method and has been employed as a photoanode in DSSCs. Incorporation of RGO into the SnO{sub 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{sub 2} when employed as a DSSC photoanode, namely poor dye adsorption and slow electron transfer rate.

  5. Fabrication of SnO{sub 2}-TiO{sub 2} core-shell nanopillar-array films for enhanced photocatalytic activity

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Hsyi-En, E-mail: sean@mail.stust.edu.tw; Lin, Chun-Yuan; Hsu, Ching-Ming

    2017-02-28

    Highlights: • SnO{sub 2}-TiO{sub 2} core-shell nanopillar-arrays on ITO glass were successfully fabricated. • The 3D heterojunction solves the problem of low photocatalytic activity of TiO{sub 2} films. • SnO{sub 2} is more suitable than ITO for the core layer to separate electron-hole pairs. - Abstract: Immobilized or deposited thin film TiO{sub 2} photocatalysts are suffering from a low photocatalytic activity due to either a low photon absorption efficiency or a high carrier recombination rate. Here we demonstrate that the photocatalytic activity of TiO{sub 2} can be effectively improved by the SnO{sub 2}-TiO{sub 2} core-shell nanopillar-array structure which combines the benefits of SnO{sub 2}/TiO{sub 2} heterojunction and high reaction surface area. The SnO{sub 2}-TiO{sub 2} core-shell nanopillar-array films were fabricated using atomic layer deposition and dry etching techniques via barrier-free porous anodic alumina templates. The photocatalytic activity of the prepared films was evaluated by methylene blue (MB) bleaching under 352 nm UV light irradiation. The results show that the photocatalytic activity of TiO{sub 2} film was 45% improved by introducing a SnO{sub 2} film between TiO{sub 2} and ITO glass substrate and was 300% improved by using the SnO{sub 2}-TiO{sub 2} core-shell nanopillar-array structure. The 45% improvement by the SnO{sub 2} interlayer is attributed to the SnO{sub 2}/TiO{sub 2} heterojunction which separates the photogenerated electron-hole pairs in TiO{sub 2} for MB degradation, and the high photocatalytic activity of the SnO{sub 2}-TiO{sub 2} core-shell nanopillar-array films is attributed to the three dimensional SnO{sub 2}/TiO{sub 2} heterojunction which owns both the carrier separation ability and the high photocatalytic reaction surface area.

  6. Synthesis of Pt{sub 75}Sn{sub 25}/SnO{sub 2}/CNT nanoscaled electrode: Low onset potential of ethanol electrooxidation

    Energy Technology Data Exchange (ETDEWEB)

    Tabet-Aoul, Amel [Institut National de la Recherche Scientifique (INRS)-Énergie, Matériaux et Télécommunications (EMT), 1650 Boulevard Lionel Boulet, Varennes, Québec, Canada J3X 1S2 (Canada); Mohamedi, Mohamed, E-mail: mohamedi@emt.inrs.ca [Institut National de la Recherche Scientifique (INRS)-Énergie, Matériaux et Télécommunications (EMT), 1650 Boulevard Lionel Boulet, Varennes, Québec, Canada J3X 1S2 (Canada)

    2013-03-15

    Highlights: ► A pulsed laser synthesis is used for the deposition of Pt, SnO{sub 2} and PtSn alloy thin films onto carbon nanotubes. ► These nanoscaled materials were characterized by FESEM, TEM, XRD and XPS. ► Enhanced electrocatalytic properties toward ethanol oxidation. -- Abstract: With the objective of lowering the potential oxidation of ethanol at PtSn nanocatalyst, we present the synthesis of free-standing catalyst layer comprising a current collector/carbon nanotubes (catalyst support)/SnO{sub 2}/Pt{sub 75}Sn{sub 25} (catalyst) nanostructured layers, each layer constructed upon the one below it. The CNTs are grown by chemical vapor deposition (CVD), whereas SnO{sub 2} and Pt{sub 75}Sn{sub 25} are synthesized by pulsed laser deposition and cross-beam laser deposition, respectively. FESEM revealed that Pt{sub 75}Sn{sub 25} nanoparticles assemble into cauliflower-like arrangement. TEM and HR-TEM showed that the Pt{sub 75}Sn{sub 25} layer thickness is of ca. 25 nm with a particle mean diameter of 4.3 nm. It was found that addition of SnO{sub 2} to Pt{sub 75}Sn{sub 25} promotes significantly the oxidation of ethanol at Pt{sub 75}Sn{sub 25} nanoparticles relative to a carbon nanotubes support. Indeed, the electrooxidation of ethanol at CNTs/SnO{sub 2}/Pt{sub 75}Sn{sub 25} electrode starts at about 100 mV negative with respect to that at CNT/Pt{sub 75}Sn{sub 25}. This decreased overpotential required to oxidize ethanol is very significant and has profound implications to developing high performing anodes for direct ethanol fuel cells technology.

  7. Nanocrystalline CdSnO3 Based Room Temperature Methanol Sensor

    Directory of Open Access Journals (Sweden)

    Shanabhau BAGUL

    2017-04-01

    Full Text Available Synthesis of nanocrystalline CdSnO3 powder by ultrasonic atomizer assisted wet chemical method is reported in this paper. Synthesized CdSnO3 powder was characterized by X-Ray Diffraction (XRD, Field Emission Scanning Electron Microscopy (FESEM and Transmission Electron Microscopy (TEM to examine phase and microstructure. FESEM and TEM analysis reveals that the CdSnO3 powder prepared here is porous monodisperse nanocrystalline in nature, with average particle size of approximately 17 nm or smaller. The material is also characterized by UV-Visible and Photoluminescence (PL spectroscopy. Thick films of synthesized CdSnO3 powder fired at 850 0C are made by using screen printing method. The films surface is modified by using dipping method. CuCl2 (0.005 M dipped (for 2 min thick film shows high response (R= 477 to 100 ppm methanol at room temperature (35 0C. The sensor shows good selectivity and fast response recovery time to methanol. The excellent methanol sensing performance, particularly high response values is observed to be mainly due to porous CdSnO3 surface.

  8. Fabrication and good ethanol sensing of biomorphic SnO2 with architecture hierarchy of butterfly wings.

    Science.gov (United States)

    Song, Fang; Su, Huilan; Han, Jie; Zhang, Di; Chen, Zhixin

    2009-12-09

    Using super-hydrophobic butterfly wings as templates, we developed an aqueous sol-gel soakage process assisted by ethanol-wetting and followed by calcination to fabricate well-organized porous hierarchical SnO(2) with connective hollow interiors and thin mesoporous walls. The exquisite hierarchical architecture of SnO(2) is faithfully replicated from the lightweight skeleton of butterfly wings at the level from nano- to macro-scales. On the basis of the self-assembly of SnO(2) nanocrystallites with diameter around 7.0 nm, the interconnected tubes (lamellas), the fastigiated hollow tubers (pillars) and the double-layered substrates further construct the biomorphic hierarchical architecture. Benefiting from the small grain size and the unique hierarchical architecture, the biomorphic SnO(2) as an ethanol sensor exhibits high sensitivity (49.8 to 50 ppm ethanol), and fast response/recovery time (11/31 s to 50 ppm ethanol) even at relatively low working temperature (170 degrees C).

  9. Fabrication and good ethanol sensing of biomorphic SnO2 with architecture hierarchy of butterfly wings

    International Nuclear Information System (INIS)

    Song Fang; Su Huilan; Han Jie; Zhang Di; Chen Zhixin

    2009-01-01

    Using super-hydrophobic butterfly wings as templates, we developed an aqueous sol-gel soakage process assisted by ethanol-wetting and followed by calcination to fabricate well-organized porous hierarchical SnO 2 with connective hollow interiors and thin mesoporous walls. The exquisite hierarchical architecture of SnO 2 is faithfully replicated from the lightweight skeleton of butterfly wings at the level from nano- to macro-scales. On the basis of the self-assembly of SnO 2 nanocrystallites with diameter around 7.0 nm, the interconnected tubes (lamellas), the fastigiated hollow tubers (pillars) and the double-layered substrates further construct the biomorphic hierarchical architecture. Benefiting from the small grain size and the unique hierarchical architecture, the biomorphic SnO 2 as an ethanol sensor exhibits high sensitivity (49.8 to 50 ppm ethanol), and fast response/recovery time (11/31 s to 50 ppm ethanol) even at relatively low working temperature (170 0 C).

  10. Facile in situ solvothermal method to synthesize MWCNT/SnIn4S8 composites with enhanced visible light photocatalytic activity

    International Nuclear Information System (INIS)

    Ding, Chaoying; Tian, Li; Liu, Bo; Liang, Qian; Li, Zhongyu; Xu, Song; Liu, Qiaoli; Lu, Dayong

    2015-01-01

    Highlights: • MWCNT/SnIn 4 S 8 composites were facilely fabricated via in situ solvothermal method. • MWCNT/SnIn 4 S 8 composites exhibited significantly enhanced visible-light activity. • MWCNT/SnIn 4 S 8 composites showed remarkable visible light photocatalytic activity. • MWCNT/SnIn 4 S 8 composites exhibited excellent photo-stability. • Possible photocatalytic mechanism under visible-light irradiation was proposed. - Abstract: Superior photocatalytic activity could be achieved by multi-walled carbon nanotube (MWCNT) incorporated in the porous assembly of marigold-like SnIn 4 S 8 heterostructures synthesized by a flexible in-situ solvothermal method. The as-prepared MWCNT/SnIn 4 S 8 composites were well-characterized by powder X-ray diffraction (XRD), transmission electron microscopy (TEM), field emission scanning electron microscopy (FE-SEM) and UV–vis diffuse reflectance spectroscopy (DRS). The photocatalytic properties of the as-prepared samples were tested by photo-degradation of aqueous malachite green (MG) under the irradiation of visible light. It was found that the MWCNT/SnIn 4 S 8 composites showed enhanced visible light photocatalytic activity for dye degradation, and an optimum photocatalytic activity was observed over 3.0 wt.% MWCNT incorporated SnIn 4 S 8 composites. The superior photocatalytic activity of MWCNT/SnIn 4 S 8 composites could be ascribed to the existence of MWCNT which could serve as a good electron acceptor, mediator as well as the co-catalyst for dye degradation. The synergistic effect between SnIn 4 S 8 and MWCNT in the composites facilitated the interfacial charge transfer driven by the excitation of SnIn 4 S 8 under visible-light irradiation. Furthermore, a possible mechanism for the photocatalytic degradation of MWCNT/SnIn 4 S 8 composites was also discussed

  11. 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.

  12. Sol–gel synthesis of SnO{sub 2}–MgO nanoparticles and their photocatalytic activity towards methylene blue degradation

    Energy Technology Data Exchange (ETDEWEB)

    Bayal, Nisha; Jeevanandam, P., E-mail: jeevafcy@iitr.ernet.in

    2013-10-15

    Graphical abstract: - Highlights: • A simple sol–gel method for the synthesis of SnO{sub 2}–MgO nanoparticles is reported. • Band gap of SnO{sub 2} can be tuned by varying the magnesium content in SnO{sub 2}–MgO. • SnO{sub 2}–MgO shows good photocatalytic activity towards degradation of methylene blue. - Abstract: SnO{sub 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{sub 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{sub 2} in the mixed metal oxide nanoparticles. The photocatalytic activity of the SnO{sub 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{sub 2} nanoparticles.

  13. 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...

  14. Comparative analysis of physico-chemical and gas sensing characteristics of two different forms of SnO{sub 2} films

    Energy Technology Data Exchange (ETDEWEB)

    Kwoka, M., E-mail: Monika.Kwoka@polsl.pl [Institute of Electronics, Silesian University of Technology, 44-100 Gliwice (Poland); Ottaviano, L. [CNR- SPIN & Department of Physics and Chemical Sciences, University of L’Aquila, 67100 (Italy); Szuber, J. [Institute of Electronics, Silesian University of Technology, 44-100 Gliwice (Poland)

    2017-04-15

    Highlights: • Two different forms of SnO{sub 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{sub 2} in NO{sub 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{sub 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{sub 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{sub 2} samples are characterized by grains/nanograins of different size and surface roughness. In turn XPS studies confirm that for both SnO{sub 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{sub 2} atmosphere of both SnO{sub 2} samples because the sensitivity is evidently smaller for RGTO SnO{sub 2} with respect to the L-CVD SnO{sub 2} samples, whereas

  15. SnO{sub 2}:F thin films deposited by RF magnetron sputtering: effect of the SnF{sub 2} amount in the target on the physical properties

    Energy Technology Data Exchange (ETDEWEB)

    De Moure F, F. [universidad Autonoma de Queretaro, Facultad de Quimica Materiales, Queretaro 76010, Queretaro (Mexico); Guillen C, A.; Nieto Z, K. E.; Quinones G, J. G.; Hernandez H, A.; Melendez L, M.; Olvera, M. de la L., E-mail: fcomoure@hotmail.com [IPN, Centro de Investigacion y de Estudios Avanzados, Departamento de Fisica, Apdo. Postal 14-740, 07360 Mexico D. F. (Mexico)

    2013-08-01

    SnO{sub 2}:F thin films were prepared by RF magnetron sputtering onto glass substrates using SnF{sub 2} as fluorine source. The films were deposited under a mixed argon/hydrogen atmosphere at a substrate temperature of 500 C. The X-ray diffraction shows that polycrystalline films were grown with a phases mixture of SnO{sub 2} and Sn O. The optical transmittance is between 80 and 90%. The physical properties of the films suggest that SnO{sub 2} thin films grown with small SnF{sub 2} content in the target can be considered as candidates for transparent electrodes. (Author)

  16. 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.

  17. K(MoO24O3(AsO4

    Directory of Open Access Journals (Sweden)

    Raja Jouini

    2013-06-01

    Full Text Available A new compound with a non-centrosymmetric structure, potassium tetrakis[dioxomolybdenum(IV] arsenate trioxide, K(MoO24O3(AsO4, has been synthesized by a solid-state reaction. The [(MoO24O3(AsO4]+ three-dimensional framework consists of single arsenate AsO4 tetrahedra, MoO6 octahedra, MoO5 bipyramids and bioctahedral units of edge-sharing Mo2O10 octahedra. The [Mo2O8]∞ octahedral chains running along the a-axis direction are connected through their corners to the AsO4 tetrahedra, MoO6 octahedra and MoO5 bipyramids, so as to form large tunnels propagating along the a axis in which the K+ cations are located. This structure is compared with compounds containing M2O10 (M = Mo, V, Fe dimers and with those containing M2O8 (M = V chains.

  18. Electrospinning direct preparation of SnO2/Fe2O3 heterojunction nanotubes as an efficient visible-light photocatalyst

    International Nuclear Information System (INIS)

    Zhu, Chengquan; Li, Yuren; Su, Qing; Lu, Bingan; Pan, Jiaqi; Zhang, Jiawang; Xie, Erqing; Lan, Wei

    2013-01-01

    Highlights: •SnO 2 /Fe 2 O 3 nano-heterojunction-tubes are prepared by a facile electrospinning technique. •The formation mechanism of heterojunction tubes is proposed for self-polymer-templates action. •SnO 2 /Fe 2 O 3 nano-heterojunction-tubes show high photocatalytic activity under visible light irradiation. •The reasons for the high photocatalytic activity are investigated in detail. -- Abstract: Herein SnO 2 /Fe 2 O 3 heterojunction nanotubes are prepared by a facile electrospinning technique. The heterojunction nanotubes with a diameter of about 200 nm uniformly distribute SnO 2 and Fe 2 O 3 nanocrystals and present the obvious interfaces between them, which form perfect SnO 2 /Fe 2 O 3 nano-heterojunctions. A possible mechanism based on self-polymer-templates is proposed to explain the formation of SnO 2 /Fe 2 O 3 heterojunction nanotubes. The heterojunction nanotubes show high photocatalytic activity for the degradation of RhB dye under visible light irradiation. The prepared SnO 2 /Fe 2 O 3 heterojunction nanotubes can also be applied to other fields such as sensor, lithium-ion batteries

  19. Metal organic frameworks-derived sensing material of SnO2/NiO composites for detection of triethylamine

    Science.gov (United States)

    Bai, Shouli; Liu, Chengyao; Luo, Ruixian; Chen, Aifan

    2018-04-01

    The SnO2/NiO composites were synthesized by hydrothermal followed by calcination using metal-organic framework (MOF) consisting of the ligand of p-benzene-dicarboxylic acid (PTA) and the Sn and Ni center ions as sacrificial templates. The structure and morphology of Sn/Ni-based MOF and SnO2/NiO composites were characterized by XRD, SEM, TEM, FT-IR, TG, XPS and Brunauer-Emmett-Teller analysis. Sensing experiments reveal that the SnO2/NiO composite with the molar ratio of 9:1 not only exhibits the highest response of 14.03 that is 3 times higher than pristine SnO2 to triethylamine at 70 °C, but also shows good selectivity. Such excellent performance is attributed to the MOF-driven strategy and the formation of p-n heterojunctions, because the metal ions can be highly dispersed and separated in the MOFs and can prevent the metal ions aggregation during the MOF decomposition process. The work is a novel route for synthesis of gas sensing material.

  20. Cu2ZnSn(S,Se)4 from CuxSnSy nanoparticle precursors on ZnO nanorod arrays

    International Nuclear Information System (INIS)

    Kavalakkatt, Jaison; Lin, Xianzhong; Kornhuber, Kai; Kusch, Patryk; Ennaoui, Ahmed; Reich, Stephanie; Lux-Steiner, Martha Ch.

    2013-01-01

    Solar cells with Cu 2 ZnSnS 4 absorber thin films have a potential for high energy conversion efficiencies with earth-abundant and non-toxic elements. In this work the formation of CZTSSe from Cu x SnS y nanoparticles (NPs) deposited on ZnO nanorod (NR) arrays as precursors for zinc is investigated. The NPs are prepared using a chemical route and are dispersed in toluene. The ZnO NRs are grown on fluorine doped SnO 2 coated glass substrates by electro deposition method. A series of samples are annealed at different temperatures between 300 °C and 550 °C in selenium containing argon atmosphere. To investigate the products of the reaction between the precursors the series is analyzed by means of X-ray diffraction (XRD) and Raman spectroscopy. The morphology is recorded by scanning electron microscopy (SEM) images of broken cross sections. The XRD measurements and the SEM images show the disappearing of ZnO NRs with increasing annealing temperature. Simultaneously the XRD and Raman measurements show the formation of CZTSSe. The formation of secondary phases and the optimum conditions for the preparation of CZTSSe is discussed. - Highlights: ► Cu x SnS y nanoparticles are deposited on ZnO nanorod arrays. ► Samples are annealed at different temperatures (300–550 °C) in Se/Ar-atmosphere. ► Raman spectroscopy, X-ray diffraction and electron microscopy are performed. ► ZnO disappears with increasing annealing temperature. ► With increasing temperature Cu x SnS y and ZnO form Cu 2 ZnSn(S,Se) 4

  1. Synthesis, Property Characterization and Photocatalytic Activity of the Novel Composite Polymer Polyaniline/Bi2SnTiO7

    Directory of Open Access Journals (Sweden)

    Yunjun Yang

    2012-03-01

    Full Text Available A novel polyaniline/Bi2SnTiO7 composite polymer was synthesized by chemical oxidation in-situ polymerization method and sol-gel method for the first time. The structural properties of novel polyaniline/Bi2SnTiO7 have been characterized by X-ray diffraction, scanning electron microscopy, X-ray photoelectron spectroscopy and X-ray spectrometry. The lattice parameter of Bi2SnTiO7 was found to be a = 10.52582(8 Å. The photocatalytic degradation of methylene blue was realized under visible light irradiation with the novel polyaniline/Bi2SnTiO7 as catalyst. The results showed that novel polyaniline/Bi2SnTiO7 possessed higher catalytic activity compared with Bi2InTaO7 or pure TiO2 or N-doped TiO2 for photocatalytic degradation of methylene blue under visible light irradiation. The photocatalytic degradation of methylene blue with the novel polyaniline/Bi2SnTiO7 or N-doped TiO2 as catalyst followed first-order reaction kinetics, and the first-order rate constant was 0.01504 or 0.00333 min−1. After visible light irradiation for 220 minutes with novel polyaniline/Bi2SnTiO7 as catalyst, complete removal and mineralization of methylene blue was observed. The reduction of the total organic carbon, the formation of inorganic products, SO42− and NO3−, and the evolution of CO2 revealed the continuous mineralization of methylene blue during the photocatalytic process. The possible photocatalytic degradation pathway of methylene blue was obtained under visible light irradiation.

  2. Magnetoresistance and phase composition of La-Sn-Mn-O systems

    DEFF Research Database (Denmark)

    Li, Z.W.; Morrish, A.H.; Jiang, Jianzhong

    1999-01-01

    The transport properties of the manganites La1 - xSnxMnO3 + delta with x = 0.1-0.5 and of Fe-doped samples have been comprehensively studied using magnetoresistance measurements, Fe-57 and Sn-119 Mossbauer spectroscopy, and x-ray diffraction. At the Sn concentration x = 0.5, La0.5Sn0.5MnO3 + delta...

  3. Facile Synthesis of Carbon-Coated Zn2SnO4 Nanomaterials as Anode Materials for Lithium-Ion Batteries

    Directory of Open Access Journals (Sweden)

    Xiaoxu Ji

    2014-01-01

    Full Text Available Carbon-coated Zn2SnO4 nanomaterials have been synthesized by a facile hydrothermal method in which as-prepared Zn2SnO4 was used as the precursor and glucose as the carbon source. The structural, morphological, and electrochemical properties were investigated by means of X-ray (XRD, scanning electron microscopy (SEM, transmission electron microscopy (TEM, and electrochemical measurement. The first discharge/charge capacity of carbon-coated Zn2SnO4 was about 1248.8 mAh/g and 873.2 mAh/g at a current density of 200 mA/g in the voltage range of 0.05 V–3.0 V, respectively, corresponding to Coulombic efficiency of 69.92%. After 40 cycles, the capacity retained 400 mAh/g, which is much better than bare Zn2SnO4.

  4. 48 CFR 24.201 - Authority.

    Science.gov (United States)

    2010-10-01

    ... 48 Federal Acquisition Regulations System 1 2010-10-01 2010-10-01 false Authority. 24.201 Section 24.201 Federal Acquisition Regulations System FEDERAL ACQUISITION REGULATION SOCIOECONOMIC PROGRAMS PROTECTION OF PRIVACY AND FREEDOM OF INFORMATION Freedom of Information Act 24.201 Authority. The Freedom of...

  5. 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.

  6. 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.

  7. 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.

  8. Electrochemical properties of SnO2/carbon composite materials as anode material for lithium-ion batteries

    International Nuclear Information System (INIS)

    Wang Jie; Zhao Hailei; Liu Xiaotong; Wang Jing; Wang Chunmei

    2011-01-01

    Highlights: → SnO 2 /carbon powders with a cauliflower-like particle structure were synthesized. → Post-annealing can improve the electrochemical properties of SnO 2 /C composite. → The 500 deg. C-annealed SnO 2 /C shows the best electrochemical performance. → The lithium ion diffusion coefficients of the SnO 2 /C electrodes were calculated. - Abstract: SnO 2 /carbon composite anode materials were synthesized from SnCl 4 .5H 2 O and sucrose via a hydrothermal route and a post heat-treatment. The synthesized spherical SnO 2 /carbon powders show a cauliflower-like micro-sized structure. High annealing temperature results in partial reduction of SnO 2 . Metallic Sn starts to emerge at 500 deg. C. High Sn content in SnO 2 /carbon composite is favorable for the increase of initial coulombic efficiency but not for the cycling stability. The SnO 2 /carbon annealed at 500 deg. C exhibits high specific capacity (∼400 mAh g -1 ), stable cycling performance and good rate capability. The generation of Li 2 O in the first lithiation process can prevent the aggregation of active Sn, while the carbon component can buffer the big volume change caused by lithiation/delithiation of active Sn. Both of them make contribution to the better cycle stability.

  9. Flower-like SnO2/graphene composite for high-capacity lithium storage

    International Nuclear Information System (INIS)

    Liu Hongdong; Huang Jiamu; Li Xinlu; Liu Jia; Zhang Yuxin; Du Kun

    2012-01-01

    Flower-like SnO 2 /graphene composite is synthesized by a simple hydrothermal method for high-capacity lithium storage. The as-prepared products are characterized by XRD, FTIR, FESEM, TGA and Nitrogen adsorption/desorption. The electrochemical performance of the flower-like SnO 2 /graphene composite is measured by cyclic voltammetry and galvanostatic charge/discharge cycling. The results show that the flower-like SnO 2 nanorod clusters are 800 nm in size and homogeneously adhere on graphene sheets. The flower-like SnO 2 /graphene composite displays superior Li-battery performance with large reversible capacity, excellent cyclic performance and good rate capability.

  10. Carbon-coated SnO2 nanotubes: template-engaged synthesis and their application in lithium-ion batteries

    Science.gov (United States)

    Wu, Ping; Du, Ning; Zhang, Hui; Yu, Jingxue; Qi, Yue; Yang, Deren

    2011-02-01

    This paper reports the synthesis of carbon-coated SnO2 (SnO2-C) nanotubes through a simple glucose hydrothermal and subsequent carbonization approach by using Sn nanorods as sacrificial templates. The as-synthesized SnO2-C nanotubes have been applied as anode materials for lithium-ion batteries, which exhibit improved cyclic performance compared to pure SnO2 nanotubes. The hollow nanostructure, together with the carbon matrix which has good buffering effect and high electronic conductivity, can be responsible for the improved cyclic performance.

  11. Characteristics of RuO{sub 2}-SnO{sub 2} nanocrystalline-embedded amorphous electrode for thin film microsupercapacitors

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Han-Ki [Core Technology Laboratory, Samsung SDI, 575 Shin-dong, Youngtong-Gu, Suwon, Gyeonggi-Do 442-391 (Korea, Republic of)]. E-mail: hanki1031.kim@samsung.com; Choi, Sun-Hee [Nano Materials Research Center, Korea Institute of Science and Technology (KIST), PO Box 131 Choengryang, Seoul 130-650 (Korea, Republic of); Yoon, Young Soo [Department of Advanced Fusion Technology (DAFT), Konkuk University, 1 Hwayang-dong, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Chang, Sung-Yong [Department of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Kwangju 500-712 (Korea, Republic of); Ok, Young-Woo [Department of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Kwangju 500-712 (Korea, Republic of); Seong, Tae-Yeon [Department of Materials Science and Engineering, Gwangju Institute of Science and Technology (GIST), Kwangju 500-712 (Korea, Republic of)

    2005-03-22

    The characteristics of RuO{sub 2}-SnO{sub 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{sub 2}/Ar ambient have RuO{sub 2}-SnO{sub 2} nanocrystallines in an amorphous oxide matrix. It is shown that the cyclic voltammorgram (CV) result of the RuO{sub 2}-SnO{sub 2} nanocrystalline-embedded amorphous film in 0.5 M H{sub 2}SO{sub 4} liquid electrolyte is similar to a bulk-type supercapacitor behavior with a specific capacitance of 62.2 mF/cm{sup 2} {mu}m. This suggests that the RuO{sub 2}-SnO{sub 2} nanocrystalline-embedded amorphous film can be employed in hybrid all-solid state energy storage devises as an electrode of supercapacitor.

  12. Graphene-SnO2 composites for highly efficient photocatalytic degradation of methylene blue under sunlight.

    Science.gov (United States)

    Seema, Humaira; Christian Kemp, K; Chandra, Vimlesh; Kim, Kwang S

    2012-09-07

    Graphene sheets decorated with SnO(2) nanoparticles (RGO-SnO(2)) were prepared via a redox reaction between graphene oxide (GO) and SnCl(2). Graphene oxide (GO) was reduced to graphene (RGO) and Sn(2+) was oxidized to SnO(2) during the redox reaction, leading to a homogeneous distribution of SnO(2) nanoparticles on RGO sheets. The scanning electron microscopy (SEM) and transmission electron microscopy (TEM) images show uniform distribution of the nanoparticles on the RGO surface and high-resolution transmission electron microscopy (HRTEM) shows an average particle size of 3-5 nm. The RGO-SnO(2) composite showed an enhanced photocatalytic degradation activity for the organic dye methylene blue under sunlight compared to bare SnO(2) nanoparticles. This result leads us to believe that the RGO-SnO(2) composite could be used in catalytic photodegradation of other organic dyes.

  13. 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.

  14. Sensors of the gas CO in thin film of SnO{sub 2}:Cu; Sensores del gas CO en pelicula delgada de SnO{sub 2}:Cu

    Energy Technology Data Exchange (ETDEWEB)

    Tirado G, S.; Sanchez Z, F. E., E-mail: tirado@esfm.ipn.mx [IPN, Escuela Superior de Fisica y Matematicas, Unidad Profesional Adolfo Lopez Mateos, San Pedro Zacatenco, 07738 Mexico D. F. (Mexico)

    2011-10-15

    Thin films of SnO{sub 2}:Cu with different thickness, were deposited on soda-lime glass substrates and prepared by the Sol-gel process and repeated immersion. The sensor properties of these films to the gas CO for the range of 0-200 ppm in the gas concentration and operating to temperatures of 23, 100, 200, and 300 C were studied. Prepared films of pure SnO{sub 2} were modified superficially with 1, 3, 5 and 10 layers of the catalyst Cu (SnO{sub 2}:Cu) with the purpose of studying the effect on the sensor capacity of the gas CO by part of the films SnO{sub 2}:Cu. Using the changes in the electric properties of the films with the incorporation of the different copper layers and experimental conditions, the sensor modifications of the gas CO were evaluated. To complete this study, was realized a characterization of the superficial morphology of the films by scanning electron microscopy and atomic force microscopy, equally was studied their structure and their electric and optical properties. (Author)

  15. 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.

  16. Neutron diffraction study of the inverse spinels Co2TiO4 and Co2SnO4

    Science.gov (United States)

    Thota, S.; Reehuis, M.; Maljuk, A.; Hoser, A.; Hoffmann, J.-U.; Weise, B.; Waske, A.; Krautz, M.; Joshi, D. C.; Nayak, S.; Ghosh, S.; Suresh, P.; Dasari, K.; Wurmehl, S.; Prokhnenko, O.; Büchner, B.

    2017-10-01

    We report a detailed single-crystal and powder neutron diffraction study of Co2TiO4 and Co2SnO4 between the temperature 1.6 and 80 K to probe the spin structure in the ground state. For both compounds the strongest magnetic intensity was observed for the (111)M reflection due to ferrimagnetic ordering, which sets in below TN=48.6 and 41 K for Co2TiO4 and Co2SnO4 , respectively. An additional low intensity magnetic reflection (200)M was noticed in Co2TiO4 due to the presence of an additional weak antiferromagnetic component. Interestingly, from both the powder and single-crystal neutron data of Co2TiO4 , we noticed a significant broadening of the magnetic (111)M reflection, which possibly results from the disordered character of the Ti and Co atoms on the B site. Practically, the same peak broadening was found for the neutron powder data of Co2SnO4 . On the other hand, from our single-crystal neutron diffraction data of Co2TiO4 , we found a spontaneous increase of particular nuclear Bragg reflections below the magnetic ordering temperature. Our data analysis showed that this unusual effect can be ascribed to the presence of anisotropic extinction, which is associated to a change of the mosaicity of the crystal. In this case, it can be expected that competing Jahn-Teller effects acting along different crystallographic axes can induce anisotropic local strain. In fact, for both ions Ti3 + and Co3 +, the 2 tg levels split into a lower dx y level yielding a higher twofold degenerate dx z/dy z level. As a consequence, one can expect a tetragonal distortion in Co2TiO4 with c /a <1 , which we could not significantly detect in the present work.

  17. Facile synthesis and characterization of NiO-SnO2 ceramic nanocomposite and its unique performance in organic pollutants degradation

    Science.gov (United States)

    Nejati Moghadam, Laya; Salavati-Niasari, Masoud

    2017-10-01

    The ceramic nanocomposite of NiO-SnO2 has been known as a professional gas sensor in many fields. In this work, this nanocomposite was prepared with a simple in-situ method successfully. NiO-SnO2 was characterized by scanning electron microscopy (SEM), X-ray diffractometry (XRD), and transmission electron microscopy (TEM). The obtained NiO-SnO2 is crystalline with a cubic structure. The photoluminescence measurement reveals one emission peak at about 3.18 eV at room temperature. In addition, this compound shows a good performance in degradation of organic dyes in a photo-catalytically reaction.

  18. 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 ...

  19. Controllable synthesis of Au@SnO2 core-shell nanohybrids with enhanced photocatalytic activities

    Science.gov (United States)

    Zhang, Shaofeng; Hao, Jinggang; Ren, Feng; Wu, Wei; Xiao, Xiangheng

    2017-05-01

    Combination of semiconductors with plasmonic nanostructures is an effective route to promote the solar light harvesting as well as the efficiency of photocatalysis. In the present work, the Au@SnO2 hybrid nanostructures with Au nanorods as the cores and highly crystallized SnO2 nanoparticles as the shells were fabricated by a facile hydrothermal method. A critical factor, which influences the coating state of the SnO2 shells over Au NRs, was found to be the concentration of CTAB agent in the system and the corresponding mechanism was also proposed. The photocatalytic activities of the Au@SnO2 nanohybrids were examined by degradation of rhodamine B (RhB) dyes at room temperature. The Au@SnO2 nanohybrids exhibited much higher catalytic activities than that of the commercial SnO2 NPs, which could be attributed to the localized electric field enhancement effect of Au nanorods plasmon and charges transfer between the Au nanorods and SnO2.

  20. 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.

  1. Photocatalytic activity of galvanically synthesized nanostructure SnO{sub 2} thin films

    Energy Technology Data Exchange (ETDEWEB)

    Jana, Sumanta, E-mail: sumantajana85@gmail.com [Department of Chemistry, Bengal Engineering and Science University, Botanic Garden, Howrah 711103, WB (India); Mitra, Bibhas Chandra [Department of Physics, Bengal Engineering and Science University, Botanic Garden, Howrah 711103, WB (India); Bera, Pulakesh [Department of Chemistry, Panskura Banamali College, Purba Medinipur, Panskura 721152, WB (India); Sikdar, Moushumi [Department of Chemistry, Bengal Engineering and Science University, Botanic Garden, Howrah 711103, WB (India); Mondal, Anup, E-mail: anupmondal2000@yahoo.co.in [Department of Chemistry, Bengal Engineering and Science University, Botanic Garden, Howrah 711103, WB (India)

    2014-07-25

    Graphical abstract: Nanostructured porous tin dioxide (SnO{sub 2}) thin films have been synthesized by simple and cost effective galvanic technique. The synthesized porous SnO{sub 2} thin films show excellent photocatalytic activity for degrading methyl orange (MO) dye under light irradiation. The porous morphological grain growth due to annealing is likely to play an active role for this degradation. - Highlights: • SnO{sub 2} thin films have been successfully synthesized by galvanic technique. • A drastic morphological change occurs after annealing as deposited SnO{sub 2} thin films. • Morphological advantage results enhanced photodegradation of dye. - Abstract: The study demonstrates an approach to synthesize nanostructure SnO{sub 2} thin films on TCO (transparent conducting oxide) coated glass substrates by galvanic technique. Aqueous solution of hydrated stannic chloride (SnCl{sub 4}⋅5H{sub 2}O) in potassium nitrate (KNO{sub 3}) solution was used as the working solution. The process involves no sophisticated reactor or toxic chemicals, and proceeds continuously under ambient condition; it provides an economic way of synthesizing nanostructure SnO{sub 2} semiconductor thin films. The influence of sintering temperature on crystalline structure, morphology, electrical and dielectric properties has been studied. A detail analysis of I−V, C−V and dielectrics for annealed SnO{sub 2} thin films have been carried out. The morphological advantage i.e. nanoporous flake like structure allows more efficient transport of reactant molecules to the active interfaces and results a strong photocatalytic activity for degrading methyl orange (MO) dye.

  2. Elastic properties of Ti-24Nb-4Zr-8Sn single crystals with bcc crystal structure

    International Nuclear Information System (INIS)

    Zhang, Y.W.; Li, S.J.; Obbard, E.G.; Wang, H.; Wang, S.C.; Hao, Y.L.; Yang, R.

    2011-01-01

    Research highlights: → The single crystals of Ti2448 alloy with the bcc crystal structure were prepared. → The elastic moduli and constants were measured by several resonant methods. → The crystal shows significant elastic asymmetry in tension and compression. → The crystal exhibits weak nonlinear elasticity with large elastic strain ∼2.5%. → The crystal has weak atomic interactions against crystal distortion to low symmetry. - Abstract: Single crystals of Ti2448 alloy (Ti-24Nb-4Zr-8Sn in wt.%) were grown successfully using an optical floating-zone furnace. Several kinds of resonant methods gave consistent Young's moduli of 27.1, 56.3 and 88.1 GPa and shear moduli of 34.8, 11.0 and 14.6 GPa for the , and oriented single crystals, and C 11 , C 12 and C 44 of 57.2, 36.1 and 35.9 GPa respectively. Uniaxial testing revealed asymmetrical elastic behaviors of the crystals: tension caused elastic softening with a large reversible strain of ∼4% and a stress plateau of ∼250 MPa, whereas compression resulted in gradual elastic stiffening with much smaller reversible strain. The crystals exhibited weak nonlinear elasticity with a large elastic strain of ∼2.5% and a high strength, approaching ∼20% and ∼30% of its ideal shear and ideal tensile strength respectively. The crystals showed linear elasticity with a small elastic strain of ∼1%. These elastic deformation characteristics have been interpreted in terms of weakened atomic interactions against crystal distortion to low crystal symmetry under external applied stresses. These results are consistent with the properties of polycrystalline Ti2448, including high strength, low elastic modulus, large recoverable strain and weak strengthening effect due to grain refinement.

  3. Surface properties and dye loading behavior of Zn{sub 2}SnO{sub 4} nanoparticles hydrothermally synthesized using different mineralizers

    Energy Technology Data Exchange (ETDEWEB)

    Annamalai, Alagappan; Eo, Yang Dam [Department of Advanced Technology Fusion, Konkuk University, 1 Hwayang-dong, Kwangjin-gu, Seoul 143-701 (Korea, Republic of); Im, Chan [Department of Chemistry, Konkuk University, 1 Hwayang-dong, Kwangjin-gu, Seoul 143-701 (Korea, Republic of); Lee, Man-Jong, E-mail: leemtx@konkuk.ac.kr [Department of Advanced Technology Fusion, Konkuk University, 1 Hwayang-dong, Kwangjin-gu, Seoul 143-701 (Korea, Republic of)

    2011-10-15

    We present for the first time the influence of different mineralizers on the isoelectric point (IEP) of zinc stannate (Zn{sub 2}SnO{sub 4}) nanoparticles hydrothermally prepared using three different mineralizers, viz., Na{sub 2}CO{sub 3}, KOH and tert-butyl amine, and the effect of the IEPs on the dye loading behavior of Zn{sub 2}SnO{sub 4} based photoelectrodes in dye sensitized solar cells (DSSCs). To produce highly crystalline, uniform sized Zn{sub 2}SnO{sub 4} nanoparticles, hydrothermal processing parameters, such as reaction temperature, time, and the mineralizers used have been critically adjusted. The structural and morphological features of the as-synthesized Zn{sub 2}SnO{sub 4} nanoparticles have been observed using both scanning and transmission electron microscopy. For the surface state characterization of shape- and size-controlled Zn{sub 2}SnO{sub 4} nanoparticles, the IEPs of Zn{sub 2}SnO{sub 4} surfaces were determined through zeta potential measurements. The IEPs were found to be 5.7, 7.4 and 8.1 for Zn{sub 2}SnO{sub 4} nanoparticles formed using Na{sub 2}CO{sub 3}, KOH and tert-butyl amine, respectively, suggesting that the surface properties of Zn{sub 2}SnO{sub 4} nanoparticles can be manipulated through the choice of the mineralizers used during the hydrothermal reaction. The amount of N719 dye loading on the surfaces of Zn{sub 2}SnO{sub 4} electrodes having different IEPs was also evaluated. It was revealed that the higher the IEP, the higher the dye loading amount, which means that the IEP mainly affects the dye loading at the dye-metal oxide interface. - Highlights: {yields} The effect of various mineralizers on the isoelectric point of Zn{sub 2}SnO{sub 4} was discussed. {yields} The IEP of Zn{sub 2}SnO{sub 4} can be modified by the choice of mineralizer. {yields} Change in IEP affects the surface properties and the morphology of Zn{sub 2}SnO{sub 4} particles. {yields} Modified surface affects the N719 dye loading behaviour of the Zn{sub 2

  4. Dielectric and magnetic properties of (Zn, Co) co-doped SnO2 nanoparticles

    International Nuclear Information System (INIS)

    Rajwali, Khan; Fang Ming-Hu

    2015-01-01

    Polycrystalline samples of (Zn, Co) co-doped SnO 2 nanoparticles were prepared using a co-precipitation method. The influence of (Zn, Co) co-doping on electrical, dielectric, and magnetic properties was studied. All of the (Zn, Co) co-doped SnO 2 powder samples have the same tetragonal structure of SnO 2 . A decrease in the dielectric constant was observed with the increase of Co doping concentration. It was found that the dielectric constant and dielectric loss values decrease, while AC electrical conductivity increases with doping concentration and frequency. Magnetization measurements revealed that the Co doping SnO 2 samples exhibits room temperature ferromagnetism. Our results illustrate that (Zn, Co) co-doped SnO 2 nanoparticles have an excellent dielectric, magnetic properties, and high electrical conductivity than those reported previously, indicating that these (Zn, Co) co-doped SnO 2 materials can be used in the field of the ultrahigh dielectric material, high frequency device, and spintronics. (paper)

  5. Controlled Synthesis of Heterostructured SnO2-CuO Composite Hollow Microspheres as Efficient Cu-Based Catalysts for the Rochow Reaction

    Directory of Open Access Journals (Sweden)

    Hezhi Liu

    2018-04-01

    Full Text Available In this work, we report the design and synthesis of a series of heterostructured SnO2-CuO hollow microspherical catalysts (H-SnO2(x-CuO, x is the weight ratio of Sn/Cu for the Rochow reaction. The microspherical catalysts with nanosheets and nanoparticles as building blocks were prepared by a facile one-pot hydrothermal method coupled with calcination. When tested for the Rochow reaction, the prepared H-SnO2(0.2-CuO composite exhibited higher dimethyldichlorosilane selectivity (88.2% and Si conversion (36.7% than the solid CuO, hollow CuO and other H-SnO2(x-CuO microspherical samples, because in the former there is a stronger synergistic interaction between CuO and SnO2.

  6. Graphene/SnO2 nanocomposite-modified electrode for electrochemical detection of dopamine

    OpenAIRE

    R. Nurzulaikha; H.N. Lim; I. Harrison; S.S. Lim; A. Pandikumar; N.M. Huang; S.P. Lim; G.S.H. Thien; N. Yusoff; I. Ibrahim

    2015-01-01

    A graphene-tin oxide (G-SnO2) nanocomposite was prepared via a facile hydrothermal route using graphene oxide and Sn precursor solution without addition of any surfactant. The hydrothermally synthesized G-SnO2 nanocomposite was characterized using a field emission scanning electron microscope (FESEM), high resolution transmission electron microscope (HRTEM), X-ray diffraction (XRD), and energy dispersive spectroscopy (EDS). A homogeneous deposition of SnO2 nanoparticles with an average partic...

  7. Magnetic property and Mössbauer analysis of SrSn{sub 1−x}Fe{sub x}O{sub 3} prepared by a sol-gel method

    Energy Technology Data Exchange (ETDEWEB)

    Nomura, Kiyoshi, E-mail: dqf10204@nifty.com [Tokyo University of Science, Photocatalysis International Research Center (Japan); Suzuki, Shigeyo; Koike, Yuya [Meiji University, Department of Science and Engineering (Japan); Li, Hongling [The University of Tokyo, Graduate School of Engineering (Japan); Okazawa, Atsushi [The University of Tokyo, Graduate School of Arts and Sciences (Japan); Kojima, Norimichi [Toyota Physical and Chemical Research Institute (Japan)

    2016-12-15

    The dilute magnetic properties of SrSn{sub 1−x}Fe{sub x}O{sub 3} (x = 0.01 − 0.15) prepared by sol-gel and thermal decomposition methods were investigated by {sup 57}Fe Mössbauer spectrometry, magnetometry, and X-ray diffractometry. It was found that SrSnO{sub 3} doped with 2–8 % Fe show weak ferromagnetism although only paramagnetic doublets are observed in {sup 57}Fe Mössbauer spectra at room temperature (RT), whereas SrSnO{sub 3} doped with 10–15 % Fe show relatively strong ferromagnetism, and the sextets are additionally observed in the {sup 57}Fe Mössbauer spectra at RT. The weak ferromagnetism by doping 2–8 % Fe is considered to be caused by the induced magnetic defects, and the ferromagnetism by doping 10–15 % Fe are considered mainly due to the magnetic coupling between dilute Fe {sup 3+} partially substituted at Sn {sup 4+} sites in the orthorhombic structure of SrSnO{sub 3−δ} accompanying the oxygen deficiencies. It is further remarkable that poor crystalline 8 % Fe doped SrSnO{sub 3−δ} obtained by annealing at 600 {sup ∘}C shows relatively high saturation magnetization and low coercivity.

  8. Efficient photocatalytic degradation of phenol in aqueous solution by SnO{sub 2}:Sb nanoparticles

    Energy Technology Data Exchange (ETDEWEB)

    Al-Hamdi, Abdullah M., E-mail: Abdullah.Al.Hamdi@lut.fi [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Chemistry Department, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Sillanpää, Mika [Laboratory of Green Chemistry, Lappeenranta University of Technology, Sammonkatu 12, 50130 Mikkeli (Finland); Bora, Tanujjal [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Dutta, Joydeep [Chair in Nanotechnology, Water Research Center, Sultan Qaboos University, P.O. Box 17, 123 Al-Khoudh (Oman); Functional Materials Division, ICT, KTH Royal Institute of Technology, Isafjordsgatan 22, SE-164 40 KistaStockholm (Sweden)

    2016-05-01

    Highlights: • Sb doped SnO{sub 2} nanoparticles were synthesized using sol–gel process. • Photocatalytic degradation of phenol were studies using SnO{sub 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{sub 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{sub 2}. In this study antimony (Sb) doped tin dioxide (SnO{sub 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{sub 2}:Sb was found to be a maximum for 0.6 wt.% Sb doped SnO{sub 2} nanoparticles with 10 mg L{sup −1} phenol in water. Within 2 h of photodegradation, more than 95% of phenol could be removed under solar light irradiation.

  9. In situ growth of SnO2 nanoparticles in heteroatoms doped cross-linked carbon frameworks for lithium ion batteries anodes

    International Nuclear Information System (INIS)

    Zhou, Xiangyang; Xi, Lihua; Chen, Feng; Bai, Tao; Wang, Biao; Yang, Juan

    2016-01-01

    Highlights: • A facile hydrothermal method is proposed to prepare cross-linked NSG/CNTs@SnO 2 . • The graphene/CNTs anchored with untrasmall SnO 2 nanoparticles can be obtained. • The N, S are successfully incorporated into the carbon matrix. • The NSG/CNTs@SnO 2 presents enhanced cycling stability and good high-rate capacity. - Abstract: SnO 2 -based nanostructures have attracted considerable interest as a promising high-capacity anode materials for lithium ion batteries. We present herein a facile one step hydrothermal approach for in situ growth of SnO 2 nanoparticles in heteroatoms doped cross-linked carbon framework (NSG/CNTs@SnO 2 ). Thiourea is employed as a single source of nitrogen and sulfur in the cross-linked carbon framework (NSG/CNTs). Characterization shows that the SnO 2 nanoparticles with an average size of 6–10 nm are uniformly anchored on NSG/CNTs matrix. When evaluated for the electrochemical properties in lithium ion batteries, the obtained NSG/CNTs@SnO 2 composite with ultrasmall SnO 2 particle size (6–10 nm) delivers a high reversible capacity of 999 mAh g −1 at 200 mA g −1 after 120 cycles and excellent rate performance. Such outstanding electrochemical performance of the peculiar cross-linked NSG/CNTs@SnO 2 composite can be primarily attributed to the synergistic effect of the ultrasmall anchored SnO 2 nanoparticles and the dual-doped NSG/CNTs matrix. The uniformly distributed SnO 2 nanoparticles can deliver large capacity and the robust dual-doped NSG/CNTs matrix can guarantee the good structural integrity and high electrical conductivity during cycling. Besides, the porous structure can provide free space for the volume expansion of SnO 2 and accommodate the strain formed during repeated lithiation/delithiation processes.

  10. 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

  11. 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

  12. Maximization of current efficiency for organic pollutants oxidation at BDD, Ti/SnO2-Sb/PbO2, and Ti/SnO2-Sb anodes.

    Science.gov (United States)

    Xing, Xuan; Ni, Jinren; Zhu, Xiuping; Jiang, Yi; Xia, Jianxin

    2018-08-01

    Whereas electrochemical oxidation is noted for its ability to degrade bio-refractory organics, it has also been incorrectly criticized for excessive energy consumption. The present paper rectifies this misunderstanding by demonstrating that the energy actually consumed in the degradation process is much less than that wasted in the side reaction of oxygen evolution. To minimize the side reaction, the possible highest instantaneous current efficiency (PHICE) for electrochemical oxidation of phenol at Boron-doped Diamond (BDD), Ti/SnO 2 -Sb/PbO 2 (PbO 2 ), and Ti/SnO 2 -Sb (SnO 2 ) anodes has been investigated systematically, and found to reach almost 100% at the BDD anode compared with 23% at the PbO 2 anode and 9% at the SnO 2 anode. The significant discrepancy between PHICE values at the various anodes is interpreted in terms of different existing forms of hydroxyl radicals. For each anode system, the PHICEs are maintained experimentally using a computer-controlled exponential decay current mode throughout the electrolysis process. For applications, the minimized energy consumption is predicted by response surface methodology, and demonstrated for the BDD anode system. Consequently, almost 100% current efficiency is achieved (for a relatively meagre energy consumption of 17.2 kWh kgCOD -1 ) along with excellent COD degradation efficiency by optimizing the initial current density, flow rate, electrolysis time, and exponential decay constant. Compared with galvanostatic conditions, over 70% of the energy is saved in the present study, thus demonstrating the great potential of electrochemical oxidation for practical applications. Copyright © 2018 Elsevier Ltd. All rights reserved.

  13. A feasibility study on SnO2/NiFe2O4 nanocomposites as anodes for Li ion batteries

    International Nuclear Information System (INIS)

    Balaji, S.; Vasuki, R.; Mutharasu, D.

    2013-01-01

    Highlights: ► The morphological analysis performed has shown the existence of nanocomposite. ► Sp. capacity after 50 cycles of pure NiFe 2 O 4 , 5 and 10 wt.% SnO 2 are 450, 750 and 780 mA h/g. ► The results are higher than the theoretical capacity of graphite (374 mA h/g). ► The capacity retention is also found to increase with SnO 2 addition in the NiFe 2 O 4 . ► Charge and discharge capacities of LiMn 2 O 4 vs. 10 wt.% SnO 2 /NiFe 2 O 4 are 232 and 138 mA h/g. -- Abstract: The SnO 2 /NiFe 2 O 4 nanocomposite samples with varying concentration of SnO 2 such as 5 wt.% and 10 wt.% were synthesized via urea assisted combustion synthesis. The kinetics of the combustion reactions were studied using thermo gravimetry analysis and from which the compound formation temperature of all the samples were observed to be below 400 °C. From the morphological analysis the grain size of NiFe 2 O 4 , 5 wt.% SnO 2 /NiFe 2 O 4 and 10 wt.% SnO 2 /NiFe 2 O 4 samples were observed to be around 1.7, 2.3 and 3.5 μm. The chrono potentiometry analyses of the samples were performed against lithium metal electrode. The capacity retention was found to be higher for composite with 10 wt.% SnO 2 . The discharge capacity of 10 wt.% SnO 2 sample with respect to Li metal and LiMn 2 O 4 electrode was observed to be around 980 mA h/g and 138 mA h/g respectively

  14. Response speed of SnO2-based H2S gas sensors with CuO nanoparticles

    International Nuclear Information System (INIS)

    Chowdhuri, Arijit; Gupta, Vinay; Sreenivas, K.; Kumar, Rajeev; Mozumdar, Subho; Patanjali, P. K.

    2004-01-01

    CuO nanoparticles on sputtered SnO 2 thin-film surface exhibit a fast response speed (14 s) and recovery time (61 s) for trace level (20 ppm) H 2 S gas detection. The sensitivity of the sensor (S∼2.06x10 3 ) is noted to be high at a low operating temperature of 130 deg. C. CuO nanoparticles on SnO 2 allow effective removal of excess adsorbed oxygen from the uncovered SnO 2 surface due to spillover of hydrogen dissociated from the H 2 S-CuO interaction

  15. Epitaxial TiO 2/SnO 2 core-shell heterostructure by atomic layer deposition

    KAUST Repository

    Nie, Anmin

    2012-01-01

    Taking TiO 2/SnO 2 core-shell nanowires (NWs) as a model system, we systematically investigate the structure and the morphological evolution of this heterostructure synthesized by atomic layer deposition/epitaxy (ALD/ALE). All characterizations, by X-ray diffraction, high-resolution transmission electron microscopy, selected area electron diffraction and Raman spectra, reveal that single crystalline rutile TiO 2 shells can be epitaxially grown on SnO 2 NWs with an atomically sharp interface at low temperature (250 °C). The growth behavior of the TiO 2 shells highly depends on the surface orientations and the geometrical shape of the core SnO 2 NW cross-section. Atomically smooth surfaces are found for growth on the {110} surface. Rough surfaces develop on {100} surfaces due to (100) - (1 × 3) reconstruction, by introducing steps in the [010] direction as a continuation of {110} facets. Lattice mismatch induces superlattice structures in the TiO 2 shell and misfit dislocations along the interface. Conformal epitaxial growth has been observed for SnO 2 NW cores with an octagonal cross-section ({100} and {110} surfaces). However, for a rectangular core ({101} and {010} surfaces), the shell also derives an octagonal shape from the epitaxial growth, which was explained by a proposed model based on ALD kinetics. The surface steps and defects induced by the lattice mismatch likely lead to improved photoluminescence (PL) performance for the yellow emission. Compared to the pure SnO 2 NWs, the PL spectrum of the core-shell nanostructures exhibits a stronger emission peak, which suggests potential applications in optoelectronics. © The Royal Society of Chemistry 2012.

  16. Fabrication and good ethanol sensing of biomorphic SnO{sub 2} with architecture hierarchy of butterfly wings

    Energy Technology Data Exchange (ETDEWEB)

    Song Fang; Su Huilan; Han Jie; Zhang Di [State Key Lab of Metal Matrix Composites, Shanghai Jiao Tong University, Shanghai 200240 (China); Chen Zhixin, E-mail: hlsu@sjtu.edu.c, E-mail: zhangdi@sjtu.edu.c [Engineering Materials Institute, Faculty of Engineering, University of Wollongong, Wollongong, NSW2522 (Australia)

    2009-12-09

    Using super-hydrophobic butterfly wings as templates, we developed an aqueous sol-gel soakage process assisted by ethanol-wetting and followed by calcination to fabricate well-organized porous hierarchical SnO{sub 2} with connective hollow interiors and thin mesoporous walls. The exquisite hierarchical architecture of SnO{sub 2} is faithfully replicated from the lightweight skeleton of butterfly wings at the level from nano- to macro-scales. On the basis of the self-assembly of SnO{sub 2} nanocrystallites with diameter around 7.0 nm, the interconnected tubes (lamellas), the fastigiated hollow tubers (pillars) and the double-layered substrates further construct the biomorphic hierarchical architecture. Benefiting from the small grain size and the unique hierarchical architecture, the biomorphic SnO{sub 2} as an ethanol sensor exhibits high sensitivity (49.8 to 50 ppm ethanol), and fast response/recovery time (11/31 s to 50 ppm ethanol) even at relatively low working temperature (170 {sup 0}C).

  17. TiO2-SnS2 nanocomposites: solar-active photocatalytic materials for water treatment.

    Science.gov (United States)

    Kovacic, Marin; Kusic, Hrvoje; Fanetti, Mattia; Stangar, Urska Lavrencic; Valant, Matjaz; Dionysiou, Dionysios D; Bozic, Ana Loncaric

    2017-08-01

    The study is aimed at evaluating TiO 2 -SnS 2 composites as effective solar-active photocatalysts for water treatment. Two strategies for the preparation of TiO 2 -SnS 2 composites were examined: (i) in-situ chemical synthesis followed by immobilization on glass plates and (ii) binding of two components (TiO 2 and SnS 2 ) within the immobilization step. The as-prepared TiO 2 -SnS 2 composites and their sole components (TiO 2 or SnS 2 ) were inspected for composition, crystallinity, and morphology using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy/energy-dispersive X-ray spectroscopy (SEM/EDX) analyses. Diffuse reflectance spectroscopy (DRS) was used to determine band gaps of immobilized TiO 2 -SnS 2 and to establish the changes in comparison to respective sole components. The activity of immobilized TiO 2 -SnS 2 composites was tested for the removal of diclofenac (DCF) in aqueous solution under simulated solar irradiation and compared with that of single component photocatalysts. In situ chemical synthesis yielded materials of high crystallinity, while their morphology and composition strongly depended on synthesis conditions applied. TiO 2 -SnS 2 composites exhibited higher activity toward DCF removal and conversion in comparison to their sole components at acidic pH, while only in situ synthesized TiO 2 -SnS 2 composites showed higher activity at neutral pH.

  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. SnO2 Nanoparticle-Based Passive Capacitive Sensor for Ethylene Detection

    Directory of Open Access Journals (Sweden)

    Mangilal Agarwal

    2012-01-01

    Full Text Available A passive capacitor-based ethylene sensor using SnO2 nanoparticles is presented for the detection of ethylene gas. The nanoscale particle size (10 nm to 15 nm and film thickness (1300 nm of the sensing dielectric layer in the capacitor model aid in sensing ethylene at room temperature and eliminate the need for microhotplates used in existing bulk SnO2-resistive sensors. The SnO2-sensing layer is deposited using room temperature dip coating process on flexible polyimide substrates with copper as the top and bottom plates of the capacitor. The capacitive sensor fabricated with SnO2 nanoparticles as the dielectric showed a total decrease in capacitance of 5 pF when ethylene gas concentration was increased from 0 to 100 ppm. A 7 pF decrease in capacitance was achieved by introducing a 10 nm layer of platinum (Pt and palladium (Pd alloy deposited on the SnO2 layer. This also improved the response time by 40%, recovery time by 28%, and selectivity of the sensor to ethylene mixed in a CO2 gas environment by 66%.

  20. Production of Sn/SnO2/MWCNT composites by plasma oxidation after thermal evaporation from pure Sn targets onto buckypapers.

    Science.gov (United States)

    Alaf, M; Gultekin, D; Akbulut, H

    2012-12-01

    In this study, tin/tinoxide/multi oxide/multi walled carbon nano tube (Sn/SnO2/MWCNT) composites were produced by thermal evaporation and then subsequent plasma oxidation. Buckypapers having controlled porosity were prepared by vacuum filtration from functionalized MWCNTs. Pure metallic tin was thermally evaporated on the buckypapers in argon atmosphere with different thicknesses. It was determined that the evaporated pure tin nano crystals were mechanically penetrated into pores of buckypaper to form a nanocomposite. The tin/MWCNT composites were subjected to plasma oxidation process at oxygen/argon gas mixture. Three different plasma oxidation times (30, 45 and 60 minutes) were used to investigate oxidation and physical and microstructural properties. The effect of coating thickness and oxidation time was investigated to understand the effect of process parameters on the Sn and SnO2 phases after plasma oxidation. Quantitative phase analysis was performed in order to determine the relative phase amounts. The structural properties were studied by field-emission gun scanning electron microscopy (FEG-SEM), atomic force microscopy (AFM) and X-ray diffraction (XRD).

  1. Change in the electrical conductivity of SnO{sub 2} crystal from n-type to p-type conductivity

    Energy Technology Data Exchange (ETDEWEB)

    Villamagua, Luis, E-mail: luis.villamagua@tyndall.ie [Grupo de Fisicoquímica de Materiales, Universidad Técnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Dipartimento di Ingegneria per l’Ambiente e il Territorio e Ingegneria Chimica, Università della Calabria, 87036 Rende (CS) (Italy); Stashans, Arvids [Grupo de Fisicoquímica de Materiales, Universidad Técnica Particular de Loja, Apartado 11-01-608, Loja (Ecuador); Lee, Po-Ming; Liu, Yen-Shuo; Liu, Cheng-Yi [Department of Chemical and Materials Engineering, National Central University, Jhong-Li, Taiwan (China); Carini, Manuela [Dipartimento di Ingegneria per l’Ambiente e il Territorio e Ingegneria Chimica, Università della Calabria, 87036 Rende (CS) (Italy)

    2015-05-01

    Highlights: • Switch from n-type to p-type conductivity in SnO{sub 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{sub 2} compound shows stable p-type conductivity. • Low resistivity (3.657 × 10{sup −1} Ω cm) has been obtained. • High carrier concentration (4.858 × 10{sup 19} cm{sup −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{sub 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{sub 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.

  2. High Performance Complementary Circuits Based on p-SnO and n-IGZO Thin-Film Transistors

    Directory of Open Access Journals (Sweden)

    Jiawei Zhang

    2017-03-01

    Full Text Available Oxide semiconductors are regarded as promising materials for large-area and/or flexible electronics. In this work, a ring oscillator based on n-type indium-gallium-zinc-oxide (IGZO and p-type tin monoxide (SnO is presented. The IGZO thin-film transistor (TFT shows a linear mobility of 11.9 cm2/(V∙s and a threshold voltage of 12.2 V. The SnO TFT exhibits a mobility of 0.51 cm2/(V∙s and a threshold voltage of 20.1 V which is suitable for use with IGZO TFTs to form complementary circuits. At a supply voltage of 40 V, the complementary inverter shows a full output voltage swing and a gain of 24 with both TFTs having the same channel length/channel width ratio. The three-stage ring oscillator based on IGZO and SnO is able to operate at 2.63 kHz and the peak-to-peak oscillation amplitude reaches 36.1 V at a supply voltage of 40 V. The oxide-based complementary circuits, after further optimization of the operation voltage, may have wide applications in practical large-area flexible electronics.

  3. High Performance Complementary Circuits Based on p-SnO and n-IGZO Thin-Film Transistors.

    Science.gov (United States)

    Zhang, Jiawei; Yang, Jia; Li, Yunpeng; Wilson, Joshua; Ma, Xiaochen; Xin, Qian; Song, Aimin

    2017-03-21

    Oxide semiconductors are regarded as promising materials for large-area and/or flexible electronics. In this work, a ring oscillator based on n-type indium-gallium-zinc-oxide (IGZO) and p-type tin monoxide (SnO) is presented. The IGZO thin-film transistor (TFT) shows a linear mobility of 11.9 cm²/(V∙s) and a threshold voltage of 12.2 V. The SnO TFT exhibits a mobility of 0.51 cm²/(V∙s) and a threshold voltage of 20.1 V which is suitable for use with IGZO TFTs to form complementary circuits. At a supply voltage of 40 V, the complementary inverter shows a full output voltage swing and a gain of 24 with both TFTs having the same channel length/channel width ratio. The three-stage ring oscillator based on IGZO and SnO is able to operate at 2.63 kHz and the peak-to-peak oscillation amplitude reaches 36.1 V at a supply voltage of 40 V. The oxide-based complementary circuits, after further optimization of the operation voltage, may have wide applications in practical large-area flexible electronics.

  4. High-mobility BaSnO{sub 3} grown by oxide molecular beam epitaxy

    Energy Technology Data Exchange (ETDEWEB)

    Raghavan, Santosh; Schumann, Timo; Kim, Honggyu; Zhang, Jack Y.; Cain, Tyler A.; Stemmer, Susanne, E-mail: stemmer@mrl.ucsb.edu [Materials Department, University of California, Santa Barbara, California 93106-5050 (United States)

    2016-01-01

    High-mobility perovskite BaSnO{sub 3} films are of significant interest as new wide bandgap semiconductors for power electronics, transparent conductors, and as high mobility channels for epitaxial integration with functional perovskites. Despite promising results for single crystals, high-mobility BaSnO{sub 3} films have been challenging to grow. Here, we demonstrate a modified oxide molecular beam epitaxy (MBE) approach, which supplies pre-oxidized SnO{sub x}. This technique addresses issues in the MBE of ternary stannates related to volatile SnO formation and enables growth of epitaxial, stoichiometric BaSnO{sub 3}. We demonstrate room temperature electron mobilities of 150 cm{sup 2} V{sup −1} s{sup −1} in films grown on PrScO{sub 3}. The results open up a wide range of opportunities for future electronic devices.

  5. Preparation and near-infrared absorption of nano-SnO{sub 2}/SiO{sub 2} assemblies with doping and without doping

    Energy Technology Data Exchange (ETDEWEB)

    Hai Shujie [Faculty of Material Science and Chemical Engineering, China University of Geosciences, Lu Mo Road 388, Wuhan 430074 (China); Yan Chunjie, E-mail: chjyan2005@126.co [Engineering Research Center of Nano-Geomaterials, Ministry of Education, China University of Geosciences, Lu Mo Road 388, Wuhan 430074 (China); Yu Hongjie; Xiao Guoqi; Wang Duo [Faculty of Material Science and Chemical Engineering, China University of Geosciences, Lu Mo Road 388, Wuhan 430074 (China)

    2009-11-20

    The assemblies of nano-SnO{sub 2}/SiO{sub 2} and Sb- or Pd-doped nano-SnO{sub 2}/SiO{sub 2}, in which the nano-SnO{sub 2} particles are located in the pores of mesoporous SiO{sub 2} dry gels, were synthesized. Only for the Sb-doped nano-SnO{sub 2}/SiO{sub 2} assemblies, a broad near-infrared absorption step occurs in the optical absorption spectrum of the wavelength range from 300 to 1500 nm. The near-infrared absorption phenomenon is attributed to electronic transitions from the ground states to the excitation states of the impurity energy levels, which are formed by Sb doping in SnO{sub 2}. With increasing the weight ratio of SnO{sub 2}:SiO{sub 2} or the annealing temperature, the near-infrared absorption step slope side exhibits 'red shift', which is caused by the quantum confinement effect weakening due to the increased SnO{sub 2} crystalline diameter.

  6. Using Ag/Ag2O/SnO2 Nanocomposites to Remove Malachite Green by a Photocatalytic Process

    Science.gov (United States)

    Taufik, A.; Paramarta, V.; Prakoso, S. P.; Saleh, R.

    2017-03-01

    Silver/silver oxide/tin oxide nanocomposites of various weight ratios were synthesized using a microwave-assisted method. The Ag/Ag2O:SnO2 nanoparticle weight ratios used were 25:75, 50:50, and 75:25. All samples were characterized using X-ray diffraction, UV-Vis spectroscopy, Differential Scanning Calorimetry and Thermogravimetric Analysis (TGA). The Ag/Ag2O/SnO2 nanocomposites contained cubic structures provided by the Ag and Ag2O and tetragonal structures provided by the SnO2. The silver resulted in surface plasmon resonance (SPR) at a wavelength of about 435 nm. The silver oxide material was transformed into pure Ag at a temperature of about 370 °C The photocatalytic activity was tested on the degradation of malachite green (MG) from an aqueous solution. The results showed that Ag/Ag2O/SnO2 at a ratio of 50:50 exhibited the best photocatalytic performance for degrading MG under visible-light irradiation. The degradation of MG using Ag/Ag2O/SnO2 nanocomposites followed pseudo first-order kinetic reactions, and electron holes were found to be the main species acting on the degradation process.

  7. Core shell structured nanoparticles of Eu3+ doped SnO2 with SiO2 shell: luminescence studies

    International Nuclear Information System (INIS)

    Ningthoujam, R.S.; Sudarsan, V.; Kulshreshtha, S.K.

    2005-01-01

    Re dispersible SnO 2 nanoparticles with and without Eu 3+ doping nanoparticles were prepared at 185 deg C by the urea hydrolysis of Sn 4+ in ethylene glycol medium. X-ray diffraction and 119 Sn MAS NMR studies of these particles revealed that these nanoparticles are crystalline with Cassiterite structure having an average crystallite size of 7 nm. Undoped SnO 2 gave a emission peak centered around 470 nm characteristic of the traps present in the nanoparticles. For Eu 3+ doped samples, emission around 590 and 615 nm was observed on both direct excitation as well as indirect excitation through traps, indicating that there is an energy transfer between the traps present in the nanoparticles and Eu 3+ ions. The asymmetric ratio of luminescence (relative intensity ratio of 590 to 615 nm transitions) has been found to be 1.2. For SnO 2 :Eu(5%)-SiO 2 nanoparticles, the asymmetric ratio of luminescence change significantly indicating the formation of nanoparticles with SnO 2 :Eu(5%) core covered with SiO 2 shell. (author)

  8. 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.

  9. 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.

  10. Structural, optical, and improved photocatalytic properties of CdS/SnO_2 hybrid photocatalyst nanostructure

    International Nuclear Information System (INIS)

    Venkata Reddy, Ch.; Ravikumar, R.V.S.S.N.; Srinivas, Ganganagunta; Shim, Jaesool; Cho, Migyung

    2017-01-01

    Highlights: • CdS, SnO_2, and a CdS/SnO_2 hybrid photocatalyst were synthesized using a two-step technique. • The dislocation density, strain values are higher for CdS/SnO_2 hybrid photocatalyst. • The CdS/SnO_2 has a higher surface area and smaller crystallite size compared to pristine CdS. • The CdS/SnO_2 catalyst greatly reduced recombination of electron and hole pairs. - Abstract: CdS, SnO_2 and CdS/SnO_2 hybrid photocatalyst nanostructure were synthesized using a two-step (co-precipitation/hydrothermal) method. The as-prepared materials were characterized by powder X-ray diffraction, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), surface analysis (BET), photoluminescence spectra (PL), UV–Vis diffusion reflectance spectroscopy (DRS), fourier transform infrared spectroscopy (FT-IR), and photocatalytic activity. The band gap energies calculated from the DRS results are 3.30, 2.15, and 2.99 eV for pristine SnO_2, CdS, and the CdS/SnO_2 hybrid photocatalyst, respectively. The CdS/SnO_2 hybrid photocatalyst showed more efficient charge carrier separation and improved photocatalytic degradation of methyl orange (MO). The highest degradation rate constant was achieved for the CdS/SnO_2 hybrid photocatalyst (0.02434 min"−"1) compared to CdS (0.01381 min"−"1) and SnO_2 (0.00878 min"−"1). The present study provides insights for improving the photocatalytic activity and photo-stability of CdS/SnO_2 hybrid photocatalyst.

  11. 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

  12. Electrochemical properties of SnO{sub 2}/carbon composite materials as anode material for lithium-ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Wang Jie [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Zhao Hailei, E-mail: hlzhao@ustb.edu.cn [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China); Beijing Key Lab of New Energy Materials and Technologies, Beijing 100083 (China); Liu Xiaotong; Wang Jing; Wang Chunmei [School of Materials Science and Engineering, University of Science and Technology Beijing, Beijing 100083 (China)

    2011-07-15

    Highlights: > SnO{sub 2}/carbon powders with a cauliflower-like particle structure were synthesized. > Post-annealing can improve the electrochemical properties of SnO{sub 2}/C composite. > The 500 deg. C-annealed SnO{sub 2}/C shows the best electrochemical performance. > The lithium ion diffusion coefficients of the SnO{sub 2}/C electrodes were calculated. - Abstract: SnO{sub 2}/carbon composite anode materials were synthesized from SnCl{sub 4}.5H{sub 2}O and sucrose via a hydrothermal route and a post heat-treatment. The synthesized spherical SnO{sub 2}/carbon powders show a cauliflower-like micro-sized structure. High annealing temperature results in partial reduction of SnO{sub 2}. Metallic Sn starts to emerge at 500 deg. C. High Sn content in SnO{sub 2}/carbon composite is favorable for the increase of initial coulombic efficiency but not for the cycling stability. The SnO{sub 2}/carbon annealed at 500 deg. C exhibits high specific capacity ({approx}400 mAh g{sup -1}), stable cycling performance and good rate capability. The generation of Li{sub 2}O in the first lithiation process can prevent the aggregation of active Sn, while the carbon component can buffer the big volume change caused by lithiation/delithiation of active Sn. Both of them make contribution to the better cycle stability.

  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. Controlled synthesis of the antiperovskite oxide superconductor Sr3‑x SnO

    Science.gov (United States)

    Hausmann, J. N.; Oudah, M.; Ikeda, A.; Yonezawa, S.; Maeno, Y.

    2018-05-01

    A large variety of perovskite oxide superconductors are known, including some of the most prominent high-temperature and unconventional superconductors. However, superconductivity among the oxidation state inverted material class, the antiperovskite oxides, was recently reported for the first time. In this superconductor, Sr3‑x SnO, the unconventional ionic state Sn4‑ is realized and possible unconventional superconductivity due to a band inversion has been discussed. Here, we discuss an improved facile synthesis method, making it possible to control the strontium deficiency in Sr3‑x SnO. Additionally, a synthesis method above the melting point of Sr3SnO is presented. We show temperature dependence of magnetization and electrical resistivity for superconducting strontium deficient Sr3‑x SnO (T c ∼ 5 K) and for Sr3SnO without a superconducting transition in alternating current susceptibility down to 0.15 K. Further, we reveal a significant effect of strontium raw material purity on the superconductivity and achieve substantially increased M/M Meissner (∼1) compared to the highest value reported so far. More detailed characterizations utilizing powder x-ray diffraction and energy-dispersive x-ray spectroscopy show that a minor cubic phase, previously suggested to be another Sr3‑x SnO phase with a slightly larger lattice parameter, is SrO. The improved characterization and controlled synthesis reported herein enable detailed investigations on the superconducting nature and its dependency on the strontium deficiency in Sr3‑x SnO.

  15. 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.

  16. Synthesis of Ce-doped SnO{sub 2} nanoparticles and their acetone gas sensing properties

    Energy Technology Data Exchange (ETDEWEB)

    Lian, Xiaoxue, E-mail: lianxiaoxues@163.com; Li, Yan; Tong, Xiaoqiang; Zou, Yunling; Liu, Xiulin; An, Dongmin; Wang, Qiong

    2017-06-15

    Highlights: • The Ce-doped SnO{sub 2} nanoparticles were fabricated via a simple hydrothermal method. • Ce ions were successfully doped into the SnO{sub 2} lattice, and 5 wt% SnO{sub 2}:Ce had a higher specific surface area. • The Ce-doped SnO{sub 2} nanoparticles exhibited the highest response values and a well selectivity to acetone. - Abstract: Hydrothermal method was generally used to synthesis nanoparticles, which was used to fabricate pure and Ce-doped (3 wt%, 5 wt%, 7 wt%) SnO{sub 2} nanoparticles in this experiment. The as-prepared products were characterized by X-ray diffraction (XRD), energy dispersive spectrum (EDS), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET). The results clearly indicated that the nanoparticles were composed of SnO{sub 2} nanoparticles and Ce ions were successfully doped into the SnO{sub 2} lattice, and 5 wt% SnO{sub 2}:Ce has a higher specific surface area (173.53 m{sup 2}/g). Importantly, SnO{sub 2}:Ce sensor had obviously improved performance compared to pure SnO{sub 2} and exhibited the highest response values (50.5 for 50 ppm) and a well selectivity to acetone at 270 °C. It could detect acetone gas in a wide concentration range with very high response, good long-term stability and repeatability of response. The possible sensing mechanism was discussed in this paper.

  17. Long afterglow property of Er"3"+ doped Ca_2SnO_4 phosphor

    International Nuclear Information System (INIS)

    Zhang, Dongyun; Shi, Mingming; Sun, Yiwen; Guo, Yunyun; Chang, Chengkang

    2016-01-01

    A novel green emitting long afterglow phosphor, Er"3"+ -doped Ca_2SnO_4 (Ca_2SnO_4:Er"3"+), was prepared successfully via a traditional high temperature solid–state reaction method. Its properties have been characterized and analyzed by utilizing x-ray diffraction (XRD), photoluminescence spectroscope (PLS), afterglow decay curve (ADC) and thermal luminescence spectroscope (TLS). Three main emission peaks of PLS locate at 524, 550 and 668 nm, corresponding to CIE chromaticity coordinates of x = 0.326, y = 0.6592. An optimal doping concentration of Er"3"+ of 2% was determined. The Ca_2SnO_4:Er"3"+ phosphors showed a typical triple-exponential afterglow decay behavior when the UV source was switched off. Thermal simulated luminescence study indicated that the persistent afterglow of Ca_2SnO_4:2 mol% Er"3"+ phosphors was generated by the suitable electron or hole traps which were resulted from the doping the Ca_2SnO_4 host with rare-earth ions (Er"3"+). - Highlights: • A novel green emitting long afterglow phosphor, Ca_2SnO_4:Er"3"+, was prepared. • An optimal doping concentration of Er"3"+ of 2% was determined. • After the UV source was turned off, the Ca_2SnO_4:Er"3"+ showed a typical triple-exponential afterglow decay behavior. • CIE chromaticity coordinates results confirmed a green light emitting of the Ca_2SnO_4:Er"3"+. • The persistent afterglow of the Ca_2SnO_4:Er"3"+ was attributed to suitable electron or hole traps.

  18. Electronic structure, magnetism and thermoelectricity in layered perovskites: Sr2SnMnO6 and Sr2SnFeO6

    Science.gov (United States)

    Khandy, Shakeel Ahmad; Gupta, Dinesh C.

    2017-11-01

    Layered structures especially perovskites have titanic potential for novel device applications and thanks to the multifunctional properties displayed in these materials. We forecast and justify the robust spin-polarized ferromagnetism in half-metallic Sr2SnFeO6 and semiconducting Sr2SnMnO6 perovskite oxides. Different approximation methods have been argued to put forward their physical properties. The intriguingly intricate electronic band structures favor the application of these materials in spintronics. The transport parameters like Seebeck coefficient, electrical and thermal conductivity, have been put together to establish their thermoelectric response. Finally, the layered oxides are found to switch their application as thermoelectric materials and hence, these concepts design the principles of the technologically desired thermoelectric and spin based devices.

  19. Highly sensitive formaldehyde resistive sensor based on a single Er-doped SnO_2 nanobelt

    International Nuclear Information System (INIS)

    Li, Shuanghui; Liu, Yingkai; Wu, Yuemei; Chen, Weiwu; Qin, Zhaojun; Gong, Nailiang; Yu, Dapeng

    2016-01-01

    SnO_2 nanobelts (SnO_2 NBs) and Er"3"+-doped SnO_2 nanobelts (Er–SnO_2 NBs) were synthesized by thermal evaporation. The obtained samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), energy dispersion spectrometer (EDS), and X-ray photoelectron spectrometer (XPS). It is found that Er–SnO_2 NBs have a good morphology with smooth surface and their thickness are about 30 nm, widths between 200 nm and 600 nm, and lengths 30–80 mm. The nanobelts with good morphology were taken to develop sensors based on a single Er–SnO_2 NB/SnO_2 NB for studying sensitive properties. The results reveal that the response of a single Er–SnO_2 nanobelt device is 9 to the formaldehyde gas with a shorter response (recovery time) of 17 (25) s.

  20. Intergrown SnO{sub 2}–TiO{sub 2}@graphene ternary composite as high-performance lithium-ion battery anodes

    Energy Technology Data Exchange (ETDEWEB)

    Jiao, Zheng; Gao, Renmei [Shanghai University, Institute of Nanochemistry and Nanobiology, School of Environmental and Chemical Engineering (China); Tao, Haihua [Inspection Center of Industrial Products and Raw Materials of SHCIQ (China); Yuan, Shuai [Shanghai University, Research Center of Nanoscience and Nanotechnology (China); Xu, Laiqiang; Xia, Saisai; Zhang, Haijiao, E-mail: hjzhang128@shu.edu.cn [Shanghai University, Institute of Nanochemistry and Nanobiology, School of Environmental and Chemical Engineering (China)

    2016-10-15

    In recent years, a lot of metal oxides with high theoretical capacity have widely investigated as the high-performance anode materials for lithium-ion batteries (LIBs). In this work, a simple, facile and effective one-pot hydrothermal strategy toward ternary SnO{sub 2}–TiO{sub 2}@graphene composite has been developed by using SnCl{sub 2} and TiOSO{sub 4} as the starting materials. The obtained composite demonstrates a unique structure and high surface areas, in which both SnO{sub 2} and TiO{sub 2} nanoparticles are well grown on the surface of graphene. More interestingly, the SnO{sub 2} and TiO{sub 2} nanoparticles are intergrowth together, totally different with the traditional ternary hybrids. When used as anode material for LIBs, the introduction of TiO{sub 2} plays a crucial role in maintaining the structural stability of the electrode during Li{sup +} insertion/extraction, which can effectively prevent the aggregation of SnO{sub 2} nanoparticles. The electrochemical tests indicate that as-prepared SnO{sub 2}–TiO{sub 2}@graphene composite exhibits a high capacity of 1276 mA h g{sup −1} after 200 cycles at the current density of 200 mA g{sup −1}. Furthermore, the composite also maintains the specific capacity of 611 mA h g{sup −1} at an ultrahigh current density of 2000 mA g{sup −1}, which is superior to those of the reported SnO{sub 2} and SnO{sub 2}/graphene hybrids. Accordingly, the remarkable electrochemical performance of ternary SnO{sub 2}–TiO{sub 2}@graphene composites is mainly attributed to their unique nanostructure, high surface areas, and the synergistic effect not only between graphene and metal oxides but also between the intergrown SnO{sub 2} and TiO{sub 2} nanoparticles.Graphical abstractIntergrown SnO{sub 2} and TiO{sub 2} nanoparticles have been successfully anchored onto the graphene nanosheets as high-performance lithium-ion battery anodes.

  1. Decolorization of Methylene Blue by Ag/SrSnO3 Composites under Ultraviolet Radiation

    Directory of Open Access Journals (Sweden)

    Patcharanan Junploy

    2014-01-01

    Full Text Available SrSn(OH6 precursors synthesized by a cyclic microwave radiation (CMR process were calcined at 900°C for 3 h to form rod-like SrSnO3. Further, the rod-like SrSnO3 and AgNO3 in ethylene glycol (EG were ultrasonically vibrated to form rod-like Ag/SrSnO3 composites, characterized by X-ray diffraction (XRD, X-ray photoelectron spectroscopy (XPS, electron microscopy (EM, Fourier transform infrared (FTIR spectroscopy, and UV-visible analysis. The photocatalyses of rod-like SrSnO3, 1 wt%, 5 wt%, and 10 wt% Ag/SrSnO3 composites were studied for degradation of methylene blue (MB, C16H18N3SCl dye under ultraviolet (UV radiation. In this research, the 5 wt% Ag/SrSnO3 composites showed the highest activity, enhanced by the electron-hole separation process. The photoactivity became lower by the excessive Ag nanoparticles due to the negative effect caused by reduction in the absorption of UV radiation.

  2. Thermoelectric Properties of SnO2 Ceramics Doped with Sb and Zn

    DEFF Research Database (Denmark)

    Yanagiya, S.; Van Nong, Ngo; Xu, Jianxiao Jackie

    2011-01-01

    Polycrystalline SnO2-based samples (Sn0.97−x Sb0.03Zn x O2, x = 0, 0.01, 0.03) were prepared by solid-state reactions. The thermoelectric properties of SnO2 doped with Sb and Zn were investigated from 300 K to 1100 K. X-ray diffraction (XRD) analysis revealed all XRD peaks of all the samples...

  3. Crystal phase analysis of SnO2-based varistor ceramic using the Rietveld method

    International Nuclear Information System (INIS)

    Moreira, M.L.; Pianaro, S.A.; Andrade, A.V.C.; Zara, A.J.

    2006-01-01

    A second addition of l mol% of CoO to a pre calcined SnO 2 -based ceramic doped with 1.0 mol% of CoO, 0.05 mol% of Nb 2 O 5 and 0.05 mol% of Cr 2 O 3 promotes the appearance of a secondary phase, Co 2 SnO 4 , besides the SnO 2 cassiterite phase, when the ceramic was sintered at 1350 deg. C/2 h. This was observed using X-ray powder diffraction, scanning electron microscopy and energy dispersive X-ray techniques. Rietveld refinement was carried out to quantify the phases present in the ceramic system. The results of the quantitative analysis were 97 wt.% SnO 2 and 3 wt.% Co 2 SnO 4 . The microstructural analysis showed that a certain amount of cobalt ion remains into cassiterite grains

  4. 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

  5. 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.

  6. Syntheses, structural variants and characterization of AInM′S{sub 4} (A=alkali metals, Tl; M′ = Ge, Sn) compounds; facile ion-exchange reactions of layered NaInSnS{sub 4} and KInSnS{sub 4} compounds

    Energy Technology Data Exchange (ETDEWEB)

    Yohannan, Jinu P.; Vidyasagar, Kanamaluru, E-mail: kvsagar@iitm.ac.in

    2016-06-15

    Ten AInM′S{sub 4} (A=alkali metals, Tl; M′= Ge, Sn) compounds with diverse structure types have been synthesized and characterized by single crystal and powder X-ray diffraction and a variety of spectroscopic methods. They are wide band gap semiconductors. KInGeS{sub 4}(1-β), RbInGeS{sub 4}(2), CsInGeS{sub 4}(3-β), TlInGeS{sub 4}(4-β), RbInSnS{sub 4}(8-β) and CsInSnS{sub 4}(9) compounds with three-dimensional BaGa{sub 2}S{sub 4} structure and CsInGeS{sub 4}(3-α) and TlInGeS{sub 4}(4-α) compounds with a layered TlInSiS{sub 4} structure have tetrahedral [InM′S{sub 4}]{sup −} frameworks. On the other hand, LiInSnS{sub 4}(5) with spinel structure and NaInSnS{sub 4}(6), KInSnS{sub 4}(7), RbInSnS{sub 4}(8-α) and TlInSnS{sub 4}(10) compounds with layered structure have octahedral [InM′S{sub 4}]{sup −} frameworks. NaInSnS{sub 4}(6) and KInSnS{sub 4}(7) compounds undergo facile topotactic ion-exchange, at room temperature, with various mono-, di- and tri-valent cations in aqueous medium to give rise to metastable layered phases. - Graphical abstract: NaInSnS{sub 4} and KInSnS{sub 4} compounds undergo, in aqueous medium at room temperature, facile topotactic ion-exchange with mono, di and trivalent cations. Display Omitted - Highlights: • Ten AInM′S{sub 4} compounds with diverse structure types were synthesized. • They are wide band gap semiconductors. • NaInSnS{sub 4} and KInSnS{sub 4} compounds undergo facile topotactic ion-exchange at room temperature.

  7. Enhanced NH3 gas sensing performance based on electrospun alkaline-earth metals composited SnO2 nanofibers

    International Nuclear Information System (INIS)

    Xu, Shuang; Kan, Kan; Yang, Ying; Jiang, Chao; Gao, Jun; Jing, Liqiang; Shen, Peikang; Li, Li

    2015-01-01

    Highlights: • The small-sized SnO 2 (5–7 nm) were obtained by adding the alkaline-earth. • Sr-composited SnO 2 nanofibers showed uniform nanotubes structure (Sr/SnO 2 ). • Sr/SnO 2 showed an excellent sensing performance to NH 3 at room temperature. - Abstract: One-dimensional alkaline-earth metals composited SnO 2 (Ae/SnO 2 ) nanofibres were fabricated via electrospinning technique, followed by thermal treatment at 600 °C for 5 h. Transmission electron microscopy (TEM) studies showed that the nanoparticles size of Ae/SnO 2 was 5–7 nm, which was smaller than the pristine SnO 2 nanorods attached by 20 nm nanoparticles. Moreover, Sr/SnO 2 nanocomposites showed uniform nanotubes structure with the wall thickness of about 30 nm, in which all the nanoparticles were connected to their neighbors by necks. The Sr/SnO 2 nanotubes exhibited an excellent sensing response toward NH 3 gas at room temperature, lower detection limit (10 ppm), faster response time (6 s towards 2000 ppm∼16 s towards 10 ppm) and better reversibility compared to the pristine SnO 2 nanorods. The enhanced sensor performances were attributed to the higher conductivity of the Sr/SnO 2 . Mott–Schottky plots (M–S) and electrochemical impedance spectroscopy (EIS) measurements indicated that the carrier density of Sr/SnO 2 nanotubes was 3 fold of that pristine SnO 2

  8. Thermal expansion and conductivity of RE2Sn2O7 (RE = La, Nd, Sm, Gd, Er and Yb) pyrochlores

    International Nuclear Information System (INIS)

    Feng, J.; Xiao, B.; Zhou, R.; Pan, W.

    2013-01-01

    Graphical abstract: Calculated cohesive energies and formation enthalpies of RE 2 Sn 2 O 7 compounds. The formation enthalpies at 298 K are more close to the experimental values. -- The calculated cohesive energies and formation enthalpies of Rare earth stannate (RE 2 Sn 2 O 7 ) compounds are in good agreement with the corresponding experimental values. The thermal expansion coefficients (TECs) of rare earth stannates are 7–9 × 10 −6 K −1 at high temperature. The results show that local spin density approximation predicts smaller TECs than the real values. The computed thermal conductivity of RE 2 Sn 2 O 7 is 1.8–2.5 W (m · K) −1 at 1273 K using the Slack–Clarke model, indicating that RE 2 Sn 2 O 7 compounds exhibit good thermal insulating properties at high temperature

  9. 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

  10. Isomer shifts and chemical bonding in crystalline Sn(II) and Sn(IV) compounds

    International Nuclear Information System (INIS)

    Terra, J.; Guenzburger, D.

    1991-01-01

    First-principles self-consistent Local Density calculations of the electronic structure of clusters representing Sn(II) (SnO, SnF 2 , SnS, SnSe) and Sn(IV) (SnO 2 , SnF 4 ) crystalline compounds were performed. Values of the electron density at the Sn nucleus were obtained and related to measured values of the Moessbauer Isomer Shifts reported in the literature. The nuclear parameter of 119 Sn derived was ΔR/R=(1.58±0.14)x10 -4 . The chemical bonding in the solids was analysed and related to the electron densities obtained. (author)

  11. 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).

  12. Influence of compositional variation on electrical properties of PANI/SnO{sub 2} nanocomposites

    Energy Technology Data Exchange (ETDEWEB)

    Chaturmukha, V. S.; Avinash, B. S.; Naveen, C. S.; Rajeeva, M. P.; Harish, B. M.; Suresha, S.; Jayanna, H. S.; Lamani, Ashok R., E-mail: ashok1571972@gmail.com [Department of PG Studies and Research in Physics, Kuvempu University, Shankaraghatta-577451, Shimoga, Karnataka (India); Prasanna, G. D. [Department of Engineering Physics, GMIT, Davangere-577006, Karnataka (India)

    2016-05-06

    Conducting polyaniline/tin oxide (PANI/SnO{sub 2}) nanocomposites have been successfully synthesized by in-situ polymerization technique. The PANI/SnO{sub 2} nanocomposites of different compositions were prepared by varying weight percentage of SnO{sub 2} nanoparticles such as 10 wt%, 20 wt%, 30 wt%, 40 wt% and 50 wt% into the fixed amount of the aniline monomer. The prepared powder samples were characterized by X-ray diffractometer (XRD), Fourier Transform Infrared spectroscopy (FT-IR) and Scanning electron microscope (SEM). The intensity of diffraction peaks for PANI/SnO{sub 2} composites is increases with increasing SnO{sub 2} wt%. SEM observation showed that the prepared SnO{sub 2} nanoparticles were uniformly dispersed and highly stabilized throughout the macromolecular chain that formed a uniform metal-polymer nanocomposite material. AC electrical conductivity and dielectric properties were studied in the frequency range of 1 KHz -1 MHz. At higher frequencies, the composites exhibit almost zero dielectric loss and maximum value of AC electrical conductivity (σ{sub ac}) of 0.21 S/m is found for a concentration of 30 wt% of SnO{sub 2} in polyaniline.

  13. A novel type heterojunction photodiodes formed junctions of Au/LiZnSnO and LiZnSnO/p-Si in series

    Energy Technology Data Exchange (ETDEWEB)

    Aydin, H. [Department of Metallurgical and Materials Science, Faculty of Engineering, Tunceli University, Tunceli (Turkey); Tataroğlu, A. [Department of Physics, Faculty of Science, Gazi University, Ankara (Turkey); Al-Ghamdi, Ahmed A. [Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); Yakuphanoglu, F., E-mail: fyhanoglu@firat.edu.tr [Department of Metallurgical and Materials Science, Faculty of Engineering, Tunceli University, Tunceli (Turkey); Department of Physics, Faculty of Science, King Abdulaziz University, Jeddah (Saudi Arabia); El-Tantawy, Farid [Department of Physics, Faculty of Science, Suez Canal University, Ismailia (Egypt); Farooq, W.A. [Physics and Astronomy Department, College of Science, King Saud University, Riyadh (Saudi Arabia)

    2015-03-15

    Highlights: • Lithium–zinc–tin–oxide thin films were prepared by sol gel method. • The Au/LiZnSnO/p-Si/Al photodiodes were fabricated using a LZTO layer grown on p-Si. • The photodiodes with Li-doped ZTO interfacial layer exhibited a better device performance. - Abstract: Lithium–zinc–tin–oxide thin films were prepared by sol gel method. The structural and optical properties of the films were investigated. The optical band gaps of the LiZnSnO films were found to be 3.78 eV for 0 at.% Li, 3.77 eV for 1 at.% Li, 3.87 eV for 3 at.% Li and 3.85 eV for 5 at.% Li, respectively. Au/LiZnSnO/p-Si/Al photodiodes were fabricated using a lithium–zinc–tin–oxide (LZTO, Li–Zn–Sn–O) layer grown on p-Si semiconductor. The electrical characteristics of the photodiodes were analyzed by current–voltage, capacitance–voltage and conductance–voltage measurements. The reverse current of the diodes increases with both the increasing illumination intensity and Li content. It was found that the Li-doped ZTO photodiodes exhibited a better device performance than those with an undoped ZTO.

  14. Structural and physical properties of transparent conducting, amorphous Zn-doped SnO2 films

    Science.gov (United States)

    Zhu, Q.; Ma, Q.; Buchholz, D. B.; Chang, R. P. H.; Bedzyk, M. J.; Mason, T. O.

    2014-01-01

    The structural and physical properties of conducting amorphous Zn-doped SnO2 (a-ZTO) films, prepared by pulsed laser deposition, were investigated as functions of oxygen deposition pressure (pO2), composition, and thermal annealing. X-ray scattering and X-ray absorption spectroscopy measurements reveal that at higher pO2, the a-ZTO films are highly transparent and have a structural framework similar to that found in crystalline (c-), rutile SnO2 in which the Sn4+ ion is octahedrally coordinated by 6 O2- ions. The Sn4+ ion in these films however has a coordination number (CN) smaller by 2%-3% than that in c-SnO2, indicating the presence of oxygen vacancies, which are the likely source of charge carriers. At lower pO2, the a-ZTO films show a brownish tint and contain some 4-fold coordinated Sn2+ ions. Under no circumstances is the CN around the Zn2+ ion larger than 4, and the Zn-O bond is shorter than the Sn-O bond by 0.07 Å. The addition of Zn has no impact on the electroneutrality but improves significantly the thermal stability of the films. Structural changes due to pO2, composition, and thermal annealing account well for the changes in the physical properties of a-ZTO films.

  15. Electrophoretic Deposition of SnO2 Nanoparticles and Its LPG Sensing Characteristics

    Directory of Open Access Journals (Sweden)

    Göktuğ Günkaya

    2015-01-01

    Full Text Available Homogenized SnO2 nanoparticles (60 nm in acetylacetone mediums, both with and without iodine, were deposited onto platinum coated alumina substrate and interdigital electrodes using the electrophoretic deposition (EPD method for gas sensor applications. Homogeneous and porous film layers were processed and analyzed at various coating times and voltages. The structure of the deposited films was characterized by a scanning electron microscopy (SEM. The gas sensing properties of the SnO2 films were investigated using liquid petroleum gas (LPG for various lower explosive limits (LEL. The results showed that porous, crack-free, and homogeneous SnO2 films were achieved for 5 and 15 sec at 100 and 150 V EPD parameters using an iodine-free acetylacetone based SnO2 suspension. The optimum sintering for the deposited SnO2 nanoparticles was observed at 500°C for 5 min. The results showed that the sensitivity of the films was increased with the operating temperature. The coated films with EPD demonstrated a better sensitivity for the 20 LEL LPG concentrations at a 450°C operating temperature. The maximum sensitivity of the SnO2 sensors at 450°C to 20 LEL LPG was 30.

  16. 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.

  17. An evolution from 3D face-centered-cubic ZnSnO3 nanocubes to 2D orthorhombic ZnSnO3 nanosheets with excellent gas sensing performance

    International Nuclear Information System (INIS)

    Chen Yuejiao; Yu Ling; Li Qing; Wu Yan; Li Qiuhong; Wang Taihong

    2012-01-01

    We have successfully observed the development of three-dimensional (3D) face-centered-cubic ZnSnO 3 into two-dimensional (2D) orthorhombic ZnSnO 3 nanosheets, which is the first observation of 2D ZnSnO 3 nanostructures to date. The synthesis from 3D to 2D nanostructures is realized by the dual-hydrolysis-assisted liquid precipitation reaction and subsequent hydrothermal treatment. The time-dependent morphology indicates the transformation via a ‘dissolution–recrystallization’ mechanism, accompanied by a ‘further growth’ process. Furthermore, the 2D ZnSnO 3 nanosheets consist of smaller sized nanoflakes. This further increases the special specific surface area and facilitates their application in gas sensing. The 2D ZnSnO 3 nanosheets exhibit excellent gas sensing properties, especially through their ultra-fast response and recovery. When exposed to ethanol and acetone, the response rate is as fast as 0.26 s and 0.18 s, respectively, and the concentration limit can reach as low as 50 ppb of ethanol. All these results are much better than those reported so far. Our experimental results indicate an efficient approach to realize high-performance gas sensors. (paper)

  18. 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.

  19. Graphene/SnO2 nanocomposite-modified electrode for electrochemical detection of dopamine

    Directory of Open Access Journals (Sweden)

    R. Nurzulaikha

    2015-09-01

    Full Text Available A graphene-tin oxide (G-SnO2 nanocomposite was prepared via a facile hydrothermal route using graphene oxide and Sn precursor solution without addition of any surfactant. The hydrothermally synthesized G-SnO2 nanocomposite was characterized using a field emission scanning electron microscope (FESEM, high resolution transmission electron microscope (HRTEM, X-ray diffraction (XRD, and energy dispersive spectroscopy (EDS. A homogeneous deposition of SnO2 nanoparticles with an average particle size of 10 nm on the graphene was observed in the FESEM and HRTEM images. The G-SnO2 nanocomposite was used to fabricate a modified electrode for the electrochemical detection of dopamine (DA in the presence of ascorbic acid (AA. Differential pulse voltammetry (DPV showed a limit of detection (LoD of 1 μM (S/N = 3 in the presence of ascorbic acid (AA. Keywords: Graphene, Tin oxide, Nanocomposite, Electrochemical sensor, Biosensor, Dopamine

  20. Sensors of the gas CO in thin film of SnO2:Cu

    International Nuclear Information System (INIS)

    Tirado G, S.; Sanchez Z, F. E.

    2011-10-01

    Thin films of SnO 2 :Cu with different thickness, were deposited on soda-lime glass substrates and prepared by the Sol-gel process and repeated immersion. The sensor properties of these films to the gas CO for the range of 0-200 ppm in the gas concentration and operating to temperatures of 23, 100, 200, and 300 C were studied. Prepared films of pure SnO 2 were modified superficially with 1, 3, 5 and 10 layers of the catalyst Cu (SnO 2 :Cu) with the purpose of studying the effect on the sensor capacity of the gas CO by part of the films SnO 2 :Cu. Using the changes in the electric properties of the films with the incorporation of the different copper layers and experimental conditions, the sensor modifications of the gas CO were evaluated. To complete this study, was realized a characterization of the superficial morphology of the films by scanning electron microscopy and atomic force microscopy, equally was studied their structure and their electric and optical properties. (Author)

  1. Ab initio study of thermoelectric properties of doped SnO{sub 2} superlattices

    Energy Technology Data Exchange (ETDEWEB)

    Borges, P.D., E-mail: pdborges@gmail.com [Instituto de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, 38810-000 Rio Paranaíba, MG (Brazil); Silva, D.E.S.; Castro, N.S.; Ferreira, C.R.; Pinto, F.G.; Tronto, J. [Instituto de Ciências Exatas e Tecnológicas, Universidade Federal de Viçosa, 38810-000 Rio Paranaíba, MG (Brazil); Scolfaro, L. [Department of Physics, Texas State University, 78666 San Marcos, TX (United States)

    2015-11-15

    Transparent conductive oxides, such as tin dioxide (SnO{sub 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{sub 2}, as well as of Sb and Zn planar (or delta)-doped layers in SnO{sub 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{sub 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{sub 2}-based alloys and superlattices. • High figure of merit is predicted for planar-doped SnO{sub 2} superlattices. • Nanotechnology has an important role for the development of thermoelectric devices.

  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. 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.

  5. The effects of surface conditions on electronic transportation mechanism of Al/SnO2/p-Si/Al structure

    International Nuclear Information System (INIS)

    Karadeniz, S.

    2001-01-01

    In the present work it was aimed to determine the effect of surface states on the electronic conductivity of Al/SnO 2 /p-Si/Al structure. In order to realize that goal, the Al/SnO 2 /p-Si/Al diodes were prepared p-types, 0.8 Ω-cm resistivity from single crystalline silicon of orientation (111). A spraying system was established in order to produce SnO 2 thin films. The morphology of SnO 2 thin films were measured by means of Atomic Force Microscope (AFM). The physical parameters which effected on the electronical conductivity of the structures were determined. The forward current-voltage (I-V) measurements were performed in the temperature range of 173-313 K. The reverse capacitance-voltage (C-V) characteristics were measured at 100 Hz, 1 kHz,10 kHz, 100 kHz, 500 kHz and 1 MHz frequencies at the same temperature range. The energy profile of the surface states effecting on diodes were determined by using high-low frequency capacitance method, Chattopadhyay method and the relation between surface states and ideality factor

  6. Preparation of ZnO-SnO2 ceramic materials by a coprecipitation method

    Directory of Open Access Journals (Sweden)

    Caballero, A. C.

    2006-06-01

    Full Text Available Tin (IV-doped zinc oxide ceramics find its main application as specific gas sensor devices. The sensor ability of the mixture and its particular affinity for a particular gas (selectivity depends both on the crystalline phases in the microstructure of the sintered semiconductor and on the degree of tin incorporation into ZnO lattice. By means of a highly reactive coprecipitation method it is revealed that the range of solid solution of tin in zinc oxide stays below 0.1 mol % of SnO2 since higher concentrations lead to segregation of a secondary Zn2SnO4 spinel type-phase.Los materiales cerámicos basados en óxido de cinc dopado con estaño (IV encuentran su principal aplicación como dispositivos sensores específicos de gases. La capacidad sensora de la mezcla de óxidos y su particular afinidad por un determinado gas específico (selectividad es función directa de cuáles sean las fases cristalinas presentes en la microestructura del semiconductor sinterizado, así como del grado de incorporación del estaño en la red del ZnO. La obtención del polvo cerámico de partida por un método de coprecipitación altamente reactivo revela que el rango de solución sólida del estaño en el óxido de cinc se encuentra por debajo del 0.1 % en moles de SnO2; concentraciones superiores llevan a la segregación de una fase secundaria, Zn2SnO4, con estructura de tipo espinela.

  7. Magnetism tuned by the charge states of defects in bulk C-doped SnO2 materials.

    Science.gov (United States)

    Lu, Ying-Bo; Ling, Z C; Cong, Wei-Yan; Zhang, Peng

    2015-10-21

    To analyze the controversial conclusions on the magnetism of C-doped SnO2 (SnO2:C) bulk materials between theoretical calculations and experimental observations, we propose the critical role of the charge states of defects in the geometric structures and magnetism, and carry out a series of first principle calculations. By changing the charge states, we can influence Bader charge distributions and atomic orbital occupancies in bulk SnO2:C systems, which consequently conduct magnetism. In all charged SnO2:C supercells, C-2px/py/pz electron occupancies are significantly changed by the charge self-regulation, and thus they make the C-2p orbitals spin polarized, which contribute to the dominant magnetic moment of the system. When the concentration of C dopant in the SnO2 supercell increases, the charge redistribution assigns extra electrons averagely to each dopant, and thus effectively modulates the magnetism. These findings provide an experimentally viable way for controlling the magnetism in these systems.

  8. Preparation of SnO{sub 2}-CNTs supported Pt catalysts and their electrocatalytic properties for ethanol oxidation

    Energy Technology Data Exchange (ETDEWEB)

    Pang, H.L.; Lu, J.P. [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China); Chen, J.H. [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China)], E-mail: chenjinhua@hnu.cn; Huang, C.T.; Liu, B.; Zhang, X.H. [State Key Laboratory of Chemo/Biosensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha 410082 (China)

    2009-03-30

    SnO{sub 2}-carbon nanotubes (CNTs) composites were prepared by sol-gel method, and characterized by scanning electron microscopy and X-ray diffraction. Due to high stability in diluted acidic solution, SnO{sub 2}-CNTs composites were selected as the catalyst support and second catalyst for ethanol electrooxidation. The electrocatalytic properties of the SnO{sub 2}-CNTs supported platinum (Pt) catalyst (Pt/SnO{sub 2}-CNTs) for ethanol oxidation have been investigated by typical electrochemical methods. Under the same mass loading of Pt, the Pt/SnO{sub 2}-CNTs catalyst shows higher electrocatalytic activity and better long-term cycle stability than Pt/SnO{sub 2} catalyst. Additionally, the effect of the mass ratio of CNTs to SnO{sub 2} on the electrocatalytic activity of the electrode for ethanol oxidation was investigated, and the optimum mass ratio of CNTs to SnO{sub 2} in the Pt/SnO{sub 2}-CNTs catalyst is 1/6.3.

  9. Facet-controlled synthesis and facet-dependent photocatalytic properties of SnO{sub 2} micropolyhedrons

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Gengxia [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics and Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Wu, Xinglong, E-mail: hkxlwu@nju.edu.cn [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics and Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Liu, Lizhe; Zhu, Xiaobin [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics and Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Zhu, Xiaoshu [Center for Analysis and Testing, Nanjing Normal University, Nanjing 210093 (China); Hao, Yanling [Key Laboratory of Modern Acoustics, MOE, Institute of Acoustics and Collaborative Innovation Center of Advanced Microstructures, National Laboratory of Solid State Microstructures, Nanjing University, Nanjing 210093 (China); Chu, Paul K. [Department of Physics and Materials Science, City University of Hong Kong, Tat Chee Avenue, Kowloon, Hong Kong (China)

    2015-09-15

    Graphical abstract: - Highlights: • SnO{sub 2} micropolyhedrons with (1 0 1) and (1 0 0) facets at different ratios are fabricated. • The vapor–solid growth mechanism of micropolyhedrons is discussed. • SnO{sub 2} octahedrons with complete (1 0 1) facets show strong photocatalytic activity. • Enhanced photocatalytic activity stems from the facet-dependent surface states. - Abstract: The facet-dependent properties of SnO{sub 2} are of fundamental and practical importance. In this study, by adjusting the deposition temperature during chemical vapor deposition, octahedral SnO{sub 2} with the exposed (1 0 1) facet and two other kinds of SnO{sub 2} polyhedrons with (1 0 1) and (1 0 0) facets with different ratios are fabricated controllably based on the vapor–solid growth mechanism. A slight increase in the deposition temperature from 1030 to 1070 °C decreases the surface energy of the reduced (1 0 1) facet with Sn termination, leading to the formation of polyhedrons with different area ratios of (1 0 1) to (1 0 0) facets. By adopting the terephthalic acid fluorescent method, the SnO{sub 2} octahedrons are demonstrated to have the strongest photocatalytic activity due to the formation of surface states induced by 5s electrons of bivalent Sn on the (1 0 1) surface. The results reveal that the photocatalytic properties of SnO{sub 2} microcrystals can be enhanced by facet-controlled synthesis.

  10. A graphene–SnO_2–TiO_2 ternary nanocomposite electrode as a high stability lithium-ion anode material

    International Nuclear Information System (INIS)

    Liang, Jicai; Wang, Juan; Zhou, Meixin; Li, Yi; Wang, Xiaofeng; Yu, Kaifeng

    2016-01-01

    In this work, a solvothermal method combined with a hydrothermal two-step method is developed to synthesize graphene–SnO_2–TiO_2 ternary nanocomposite, in which the nanometer-sized TiO_2 and SnO_2 nanoparticles form in situ uniformly anchored on the surface of graphene sheets, as high stability and capacity lithium-ion anode materials. Compared to graphene–TiO_2, bulk TiO_2 and grapheme–SnO_2 composites, the as-prepared nanocomposite delivers a superior rate performance of 499.3 mAhg"−"1 at 0.2 C and an outstanding stability cycling capability (1073.4 mAhg"−"1 at 0.2 C after 50 cycles), due to the synergistic effects contributed from individual components, for example, high specific capacity of SnO_2, excellent conductivity of 3D graphene networks. - Graphical abstract: Graphene–SnO_2–TiO_2 nanocomposite is synthesized by a hydrothermal two-step method. The composite exhibits higher reversible capacity and better cycle/rate performance due to the unique structure. - Highlights: • We have synthesized a graphene–SnO_2–TiO_2 nanocomposite by a two-step method to improve the cycling performance. • Graphene–SnO_2–TiO_2 nanocomposite is synthesized by a hydrothermal two-step method. • The composite exhibits higher reversible capacity and better cycle/rate performance due to the unique structure.

  11. 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.

  12. 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

  13. Reduced graphene oxide decorated with Fe doped SnO{sub 2} nanoparticles for humidity sensor

    Energy Technology Data Exchange (ETDEWEB)

    Toloman, D. [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293 Cluj-Napoca (Romania); Popa, A., E-mail: popa@itim-cj.ro [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293 Cluj-Napoca (Romania); Stan, M.; Socaci, C.; Biris, A.R. [National Institute for Research and Development of Isotopic and Molecular Technologies, 67-103 Donat Street, 400293 Cluj-Napoca (Romania); Katona, G. [Babes-Bolyai University, Faculty of Chemistry and Chemical Engineering, 11 Arany Janos Street, 400028 Cluj-Napoca (Romania); Tudorache, F. [Interdisciplinary Research Department – Field Science & RAMTECH, Al. I. Cuza University, 11 Carol I Blvd., 7000506 Iasi (Romania); Petrila, I. [Interdisciplinary Research Department – Field Science & RAMTECH, Al. I. Cuza University, 11 Carol I Blvd., 7000506 Iasi (Romania); Faculty of Automatic Control and Computer Engineering, Gheorghe Asachi Technical University, 27 Dimitrie Mangeron Street, 700050 Iasi (Romania); Iacomi, F. [Faculty of Physics, Al. I. Cuza University, 11 Carol I Blvd., 7000506 Iasi (Romania)

    2017-04-30

    Highlights: • Reduced graphene oxide decorated with Fe doped SnO{sub 2} nanoparticles were synthesized. • The decoration of rGO layers with SnO{sub 2}:Fe nanoparticles was highlited by TEM. • The reduction of graphene oxide was evidenced using XRD and FT-IR. • Sensitivity tests for relative humidity (RH) were carried out. • The composite sensor exhibited enhanced sensing response as compared with Fe:SnO{sub 2}. - Abstract: Reduced graphene oxide (rGO) decorated with Fe doped SnO{sub 2} nanoparticles were fabricated via the electrostatic interaction between positively charged modified Fe-doped SnO{sub 2} oxide and negatively charged graphene oxide (GO) in the presence of poly(allylamine) hydrochloride (PAH). The decoration of rGO layers with SnO{sub 2}:Fe nanoparticles was highlited by TEM microsopy. For composite sample the diffraction patterns coincide well with those of SnO{sub 2}:Fe nanoparticles. The reduction of graphene oxide was evidenced using XRD and FT-IR spectroscopy. The formation of SnO{sub 2}:Fe-PAH-graphene composites was confirmed by FT-IR, Raman and EPR spectroscopy. Sensitivity tests for relative humidity (RH) measurements were carried out at five different concentrations of humid air at room temperature. The prepared composite sensor exhibited a higher sensing response as compared with Fe:SnO{sub 2} nanoparticles.

  14. Multi-yolk-shell SnO2/Co3Sn2@C Nanocubes with High Initial Coulombic Efficiency and Oxygen Reutilization for Lithium Storage.

    Science.gov (United States)

    Su, Liwei; Xu, Yawei; Xie, Jian; Wang, Lianbang; Wang, Yuanhao

    2016-12-28

    The challenging problems of SnO 2 anode material for lithium ion batteries are the poor electronic conductivity and the low oxygen reutilization due to the irreversibility of Li 2 O generated in the initial discharge leading to a theoretical initial Coulombic efficiency (ICE) of only 52.4%. Different from these strategies, this work proposes a novel strategy to level up the oxygen reutilization in SnO 2 by introducing Co 3 Sn 2 nanoalloys which can release Co atoms to reversibly react with Li 2 O instead. According to this protocol, multi-yolk-shell SnO 2 /Co 3 Sn 2 @C nanocubes are designed and successfully prepared using hollow CoSn(OH) 6 nanocubes as precursors followed a hydrothermal carbon coating and calcination treatment. The unique multi-yolk-shell nanostructure offers adequate breathing space for the volumetric deformation during long-term cycling. Moreover, the removal of Li 2 O allows a high electronic conductivity and resultant rate performance. As a result, the efficient reutilization of oxygen enables a high ICE of 71.7% and a reversible capacity of 1003 mA h g -1 after 200 cycles at 100 mA g -1 . Cyclic voltammetry, cycling performance at different voltage windows, and X-ray photoelectron spectroscopy confirm the proposed mechanism. This strategy employing oxygen-poor metals or alloys provides a novel approach to enhance the oxygen reutilization in SnO 2 for higher reversibility.

  15. Synthesis, structure, and luminescence properties of In{sub 2}Ge{sub 2}O{sub 7}/SnO{sub 2} core-shell nanowires

    Energy Technology Data Exchange (ETDEWEB)

    Park, Sunghoon; An, Soyeon; Jin, Changhyun; Lee, Chongmu [Inha University, Incheon (Korea, Republic of)

    2012-09-15

    In{sub 2}Ge{sub 2}O{sub 7}/SnO{sub 2} core-shell nanowires were synthesized by using a two-step process: thermal evaporation of a mixture of In and Ge powders and atomic layer deposition of SnO{sub 2}. The core-shell nanowires were characterized using by scanning electron microscopy, transmission electron microscopy, X-ray diffraction, and photoluminescence spectroscopy. The In{sub 2}Ge{sub 2}O{sub 7} cores in these core-shell nanowires varied from 50 to 100 nanometers in diameter and up to a few hundreds of micrometers in length, and the SnO{sub 2} shell layer thickness ranged from 5 to 15 nm. Photoluminescence measurements showed that the In{sub 2}Ge{sub 2}O{sub 7} nanowires had a weak broad violet emission band centered at approximately 405 nm. In contrast, the In{sub 2}Ge{sub 2}O{sub 7}/SnO{sub 2} core-shell nanowires had a taller blue-violet emission peak at approximately 440 nm. The optimum shell layer thickness of the In{sub 2}Ge{sub 2}O{sub 7}/SnO{sub 2} core-shell nanowires for the highest PL intensity was found to be 15 nm. Our results also showed that the intensity of the blue-violet emission was increased further by thermal annealing in an Ar atmosphere. The origins of the change on and the enhancement of the luminescence of the In{sub 2}Ge{sub 2}O{sub 7} nanowires by SnO{sub 2} coating and annealing are discussed.

  16. SnO{sub 2}/reduced graphene oxide composite films for electrochemical applications

    Energy Technology Data Exchange (ETDEWEB)

    Bondarenko, E.A. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Mazanik, A.V., E-mail: mazanikalexander@gmail.com [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Streltsov, E.A. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus); Kulak, A.I., E-mail: kulak@igic.bas-net.by [Institute of General and Inorganic Chemistry, National Academy of Sciences of Belarus, Surganova str., 9/1, Minsk 220072 (Belarus); Korolik, O.V. [Belarusian State University, Nezalezhnastsi Av. 4, Minsk 220030 (Belarus)

    2015-12-15

    Highlights: • SnO{sub 2}/GO composites with mass fraction of carbon phase 0.01% ≤ w{sub C} ≤ 80% have been formed. • 400 °C annealing was applied for GO reduction in the composites. • SnO{sub 2}/rGO composites demonstrate a high electrocatalytic activity in anodic processes. • Exchange current density grows linearly with carbon phase concentration at w{sub C} ≤ 10%. - Abstract: SnO{sub 2}/GO (GO is graphene oxide) composite films with GO mass fraction w{sub C} ranging from 0.01 to 80% have been prepared using colloidal solutions. Heat treatment of SnO{sub 2}/GO films in Ar atmosphere at 400 °C leads to GO reduction accompanied by partial exfoliation and decreasing of the particle thickness. SnO{sub 2}/rGO (rGO is reduced GO) film electrodes demonstrate a high electrocatalytic activity in the anodic oxidation of inorganic (iodide-, chloride-, sulfite-anions) and organic (ascorbic acid) substances. The increase of the anodic current in these reactions is characterized by overpotential inherent to the individual rGO films and exchange current density grows linearly with rGO concentration at w{sub C} ≤ 10% indicating that the rGO particles in composites act as sites of electrochemical process. The SnO{sub 2}/rGO composite films, in which the chemically stable oxide matrix encapsulates the rGO inclusions, can be considered as a promising material for applied electrochemistry.

  17. 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

  18. 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.

  19. 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.

  20. Graphene-SnO2 nanocomposites decorated with quantum tunneling junctions: preparation strategies, microstructures and formation mechanism.

    Science.gov (United States)

    Wang, Qingxiu; Wu, Xianzheng; Wang, Lijun; Chen, Zhiwen; Wang, Shilong

    2014-09-28

    Tin dioxide (SnO2) and graphene are versatile materials that are vitally important for creating new functional and smart materials. A facile, simple and efficient ultrasonic-assisted hydrothermal synthesis approach has been developed to prepare graphene-SnO2 nanocomposites (GSNCs), including three samples with graphene/Sn weight ratios = 1 : 2 (GSNC-2), 1 : 1 (GSNC-1), and graphene oxide/Sn weight ratio = 1 : 1 (GOSNC-1). Low-magnification electron microscopy analysis indicated that graphene was exfoliated and adorned with SnO2 nanoparticles, which were dispersed uniformly on both the sides of the graphene nanosheets. High-magnification electron microscopy analysis confirmed that the graphene-SnO2 nanocomposites presented network tunneling frameworks, which were decorated with the SnO2 quantum tunneling junctions. The size distribution of SnO2 nanoparticles was estimated to range from 3 to 5.5 nm. Comparing GSNC-2, GSNC-1, and GOSNC-1, GOSNC-1 was found to exhibit a significantly better the homogeneous distribution and a considerably smaller size distribution of SnO2 nanoparticles, which indicated that it was better to use graphene oxide as a supporting material and SnCl4·5H2O as a precursor to synthesize hybrid graphene-SnO2 nanocomposites. Experimental results suggest that the graphene-SnO2 nanocomposites with interesting SnO2 quantum tunneling junctions may be a promising material to facilitate the improvement of the future design of micro/nanodevices.

  1. SnO2 quantum dots with rapid butane detection at lower ppm-level

    Science.gov (United States)

    Cai, Pan; Dong, Chengjun; Jiang, Ming; Shen, Yuanyuan; Tao, You; Wang, Yude

    2018-04-01

    SnO2 quantum dots (QDs) were successfully synthesized by a facile approach employing benzyl alcohol and ammonium hydroxide at lower temperature of 130 °C. It is revealed that the SnO2 QDs is about 3 nm in size to form clusters. The gas sensor based on SnO2 QDs shows a high potential for detecting low-ppm-level butane at 400 °C, exhibiting a high sensitivity, short response and rapid recovery time, and effective selectivity. The sensing mechanism is understood in terms of adsorbed oxygen species. Significantly, the excellent sensing performance is attributed to the smaller size of SnO2 and larger surface area (204.85 m2/g).

  2. 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

  3. Triboelectric charge generation by semiconducting SnO2 film grown by atomic layer deposition

    Science.gov (United States)

    Lee, No Ho; Yoon, Seong Yu; Kim, Dong Ha; Kim, Seong Keun; Choi, Byung Joon

    2017-07-01

    Improving the energy harvesting efficiency of triboelectric generators (TEGs) requires exploring new types of materials that can be used, and understanding their properties. In this study, we have investigated semiconducting SnO2 thin films as friction layers in TEGs, which has not been explored thus far. Thin films of SnO2 with various thicknesses were grown by atomic layer deposition on Si substrates. Either polymer or glass was used as counter friction layers. Vertical contact/separation mode was utilized to evaluate the TEG efficiency. The results indicate that an increase in the SnO2 film thickness from 5 to 25 nm enhances the triboelectric output voltage of the TEG. Insertion of a 400-nm-thick Pt sub-layer between the SnO2 film and Si substrate further increased the output voltage up to 120 V in a 2 cm × 2 cm contact area, while the enhancement was cancelled out by inserting a 10-nm-thick insulating Al2O3 film between SnO2 and Pt films. These results indicate that n-type semiconducting SnO2 films can provide triboelectric charge to counter-friction layers in TEGs.[Figure not available: see fulltext.

  4. 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.

  5. All-perovskite transparent high mobility field effect using epitaxial BaSnO3 and LaInO3

    Directory of Open Access Journals (Sweden)

    Useong Kim

    2015-03-01

    Full Text Available We demonstrate an all-perovskite transparent heterojunction field effect transistor made of two lattice-matched perovskite oxides: BaSnO3 and LaInO3. We have developed epitaxial LaInO3 as the gate oxide on top of BaSnO3, which were recently reported to possess high thermal stability and electron mobility when doped with La. We measured the dielectric properties of the epitaxial LaInO3 films, such as the band gap, dielectric constant, and the dielectric breakdown field. Using the LaInO3 as a gate dielectric and the La-doped BaSnO3 as a channel layer, we fabricated field effect device structure. The field effect mobility of such device was higher than 90 cm2 V−1 s−1, the on/off ratio was larger than 107, and the subthreshold swing was 0.65 V dec−1. We discuss the possible origins for such device performance and the future directions for further improvement.

  6. Low-temperature-fabricated ZnO, AZO, and SnO{sub 2} nanoparticle-based dye-sensitized solar cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Hong Hee; Park, Cheolmin; Choi, Wonkook; Cho, Sungjae; Moon, Byungjoon; Son, Dongick [Korea Institute of Science and Technology, Seoul (Korea, Republic of); Yonsei University, Seoul (Korea, Republic of)

    2014-11-15

    The authors investigated the microstructural and the electrical properties of ZnO, AZO, and SnO{sub 2} based dye-sensitized solar cells (DSSCs) fabricated using a low-temperature-processed (200 .deg. C) dyesensitized ZnO, AZO, and SnO{sub 2} nanoparticle thin film and a Pt catalyst deposited on ITO/glass by RF magnetron sputtering. A hydropolymer containing PEG (poly ethylene glycol) and PEO (poly ethylene oxide) is used to make uniformly-distributed ZnO, AZO, and SnO{sub 2} nanoparticle layer which forms a nano porous ZnO, AZO, and SnO{sub 2} network after heat treatment. The layer is then dye sensitized and sandwiched between two electrodes in an electrolyte to make a DSSC device. The highest measured parameters, the short-circuit current density (J{sub sc}), the open circuit potential (V{sub oc}), the fill factor (FF), and power conversion efficiency (η), of the DSSC fabricated wander optimized conditions were observed to be 5.10 mA/cm{sup 2}, 0.61 V, 0.46, and 1.43%, respectively.

  7. Characterization of Industrial Pt-Sn/Al2O3 Catalyst and Transient Product Formations during Propane Dehydrogenation

    Directory of Open Access Journals (Sweden)

    Kah Sing Ho

    2013-06-01

    Full Text Available The major problem plaguing propane dehydrogenation process is the coke formation on the Pt-Sn/Al2O3 catalyst which leads to catalyst deactivation. Due to information paucity, the physicochemical characteristics of the commercially obtained regenerated Pt-Sn/Al2O3 catalyst (operated in moving bed reactor and coke formation at different temperatures of reaction were discussed. The physicochemical characterization of regenerated catalyst gave a BET surface area of 104.0 m2/g with graphitic carbon content of 8.0% indicative of incomplete carbon gasification during the industrial propylene production. Effect of temperatures on coke formation was identified by studying the product yield via temperature-programmed reaction carried out at 500oC, 600oC and 700oC. It was found that ethylene was precursor to carbon laydown while propylene tends to crack into methane. Post reaction, the spent catalyst possessed relatively lower surface area and pore radius whilst exhibited higher carbon content (31.80% at 700oC compared to the regenerated catalyst. Significantly, current studies also found that higher reaction temperatures favoured the coke formation. Consequently, the propylene yield has decreased with reaction temperature. © 2013 BCREC UNDIP. All rights reservedReceived: 10th March 2013; Revised: 28th April 2013; Accepted: 6th May 2013[How to Cite: Kah, S.H., Joanna Jo, E.C., Sim, Y.C., Chin, K.C. (2013. Characterization of Industrial Pt-Sn/Al2O3 Catalyst and Transient Product Formations during Propane Dehydrogenation. Bulletin of Chemical Reaction Engineering & Catalysis, 8 (1: 77-82. (doi:10.9767/bcrec.8.1.4569.77-82][Permalink/DOI: http://dx.doi.org/10.9767/bcrec.8.1.4569.77-82] | View in  |

  8. Dopant-site-dependent scattering by dislocations in epitaxial films of perovskite semiconductor BaSnO3

    Directory of Open Access Journals (Sweden)

    Useong Kim

    2014-05-01

    Full Text Available We studied the conduction mechanism in Sb-doped BaSnO3 epitaxial films, and compared its behavior with that of the mechanism of its counterpart, La-doped BaSnO3. We found that the electron mobility in BaSnO3 films was reduced by almost 7 times when the dopant was changed from La to Sb, despite little change in the effective mass of the carriers. This indicates that the scattering rate of conduction electrons in the BaSnO3 system is strongly affected by the site at which the dopants are located. More importantly, we found that electron scattering by threading dislocations also depends critically on the dopant site. We propose that the large enhancement of scattering by the threading dislocations in Sb-doped BaSnO3 films is caused by the combination effect of the change in the distribution of Sb impurities in the films, the formation of the Sb impurity clusters near the threading dislocations, and the conduction electron clustering near the Sb impurities.

  9. K2 ZnSn3 Se8 : A Non-Centrosymmetric Zinc Selenidostannate(IV) Featuring Interesting Covalently Bonded [ZnSn3 Se8 ]2- Layer and Exhibiting Intriguing Second Harmonic Generation Activity.

    Science.gov (United States)

    Zhou, Molin; Jiang, Xingxing; Yang, Yi; Guo, Yangwu; Lin, Zheshuai; Yao, JJiyong; Wu, Yicheng

    2017-06-19

    Non-centrosymmetric zinc selenidostannate(IV) K 2 ZnSn 3 Se 8 was synthesized. It features interesting covalently bonded [ZnSn 3 Se 8 ] 2- layers with K + cations filling in the interlayer voids. The phonon spectrum was calculated to clarify its structural stability. Based on the X-ray diffraction data along with the Raman spectrum, the major bonding features of the title compound were identified. According to the UV/vis-NIR spectroscopy, K 2 ZnSn 3 Se 8 possesses a typical direct band gap of 2.10 eV, which is in good agreement with the band structure calculations. Moreover, our experimental measurements and detailed theoretical calculations reveal that K 2 ZnSn 3 Se 8 is a new phase-matchable nonlinear optical material with a powder second harmonic generation (SHG) signal about 0.6 times of that of AgGaS 2 . © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Structural, optical, and improved photocatalytic properties of CdS/SnO{sub 2} hybrid photocatalyst nanostructure

    Energy Technology Data Exchange (ETDEWEB)

    Venkata Reddy, Ch., E-mail: cvrphy@gmail.com [School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Ravikumar, R.V.S.S.N. [Department of Physics, Acharya Nagarjuna University, Nagarjuna Nagar 522510 (India); Srinivas, Ganganagunta [Engineering Department, lbra College of Technology, lbra 400 (Oman); Shim, Jaesool, E-mail: jshim@ynu.ac.kr [School of Mechanical Engineering, Yeungnam University, Gyeongsan 712-749 (Korea, Republic of); Cho, Migyung, E-mail: mgcho@tu.ac.kr [Department of Game Engineering, Tongmyong University, Busan 608-711 (Korea, Republic of)

    2017-07-15

    Highlights: • CdS, SnO{sub 2}, and a CdS/SnO{sub 2} hybrid photocatalyst were synthesized using a two-step technique. • The dislocation density, strain values are higher for CdS/SnO{sub 2} hybrid photocatalyst. • The CdS/SnO{sub 2} has a higher surface area and smaller crystallite size compared to pristine CdS. • The CdS/SnO{sub 2} catalyst greatly reduced recombination of electron and hole pairs. - Abstract: CdS, SnO{sub 2} and CdS/SnO{sub 2} hybrid photocatalyst nanostructure were synthesized using a two-step (co-precipitation/hydrothermal) method. The as-prepared materials were characterized by powder X-ray diffraction, transmission electron microscopy (TEM), high-resolution transmission electron microscopy (HRTEM), X-ray photoelectron spectroscopy (XPS), surface analysis (BET), photoluminescence spectra (PL), UV–Vis diffusion reflectance spectroscopy (DRS), fourier transform infrared spectroscopy (FT-IR), and photocatalytic activity. The band gap energies calculated from the DRS results are 3.30, 2.15, and 2.99 eV for pristine SnO{sub 2}, CdS, and the CdS/SnO{sub 2} hybrid photocatalyst, respectively. The CdS/SnO{sub 2} hybrid photocatalyst showed more efficient charge carrier separation and improved photocatalytic degradation of methyl orange (MO). The highest degradation rate constant was achieved for the CdS/SnO{sub 2} hybrid photocatalyst (0.02434 min{sup −1}) compared to CdS (0.01381 min{sup −1}) and SnO{sub 2} (0.00878 min{sup −1}). The present study provides insights for improving the photocatalytic activity and photo-stability of CdS/SnO{sub 2} hybrid photocatalyst.

  11. Phase transition and conduction mechanism in Pb{sub 2}Na{sub 0.8}R{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} material (R=rare earth)

    Energy Technology Data Exchange (ETDEWEB)

    Bouziane, M. [Laboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Batouta, BP 1014 Rabat (Morocco); Taibi, M., E-mail: taibiens@yahoo.fr [Laboratoire de Physico-Chimie des Matériaux (LAF 502), Ecole Normale Supérieure, Université Mohammed V-Agdal, BP 5118 Rabat (Morocco); Boukhari, A. [Laboratoire de Chimie du Solide Appliquée, Faculté des Sciences, Université Mohammed V-Agdal, Avenue Ibn Batouta, BP 1014 Rabat (Morocco)

    2013-11-15

    Electrical properties of Pb{sub 2}Na{sub 0.8}Eu{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} tungsten bronze compound were investigated. Ferroelectric phase transition of diffuse type is observed at 395 °C. Conductivity study as a function of temperature (RT-600 °C) and at three different frequencies (10, 100 and 1000 kHz) suggests the existence of dominant ionic conduction. The rise of ac conductivity on increasing temperature supports the NTCR (negative temperature coefficient of resistance) behaviour of the material. The activation energies have been evaluated from ac conductivity using Arrhenius equation and discussed. Different conduction mechanisms were identified. For comparison, the conducting properties of Pb{sub 2}Na{sub 0.8}R{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} (R=Dy, Nd, La) were also investigated. - Graphical abstract: Thermal evolution of lnσ{sub ac} of Pb{sub 2}Na{sub 0.8}Eu{sub 0.2}Nb{sub 4.8}Fe{sub 0.2}O{sub 15} at selected frequencies. Display Omitted - Highlights: • We found that TB compounds exhibit a diffuse type of first- order transition. • A negative temperature coefficient of resistance (NTCR) behaviour is observed. • Three conduction mechanisms were identified: n-and/or p-type at low temperatures. • The conduction mechanism in the studied compounds is very complex.

  12. Facile template-directed synthesis of carbon-coated SnO2 nanotubes with enhanced Li-storage capabilities

    International Nuclear Information System (INIS)

    Zhu, Xiaoshu; Zhu, Jingyi; Yao, Yinan; Zhou, Yiming; Tang, Yawen; Wu, Ping

    2015-01-01

    Herein, a novel type of carbon-coated SnO 2 nanotubes has been designed and synthesized through a facile two-step hydrothermal approach by using ZnO nanorods as templates. During the synthetic route, SnO 2 nanocrystals and carbon layer have been uniformly deposited on the rod-like templates in sequence, meanwhile ZnO nanorods could be in situ dissolved owing to the generated alkaline and acidic environments during hydrothermal coating of SnO 2 nanocrystals and hydrothermal carbonization of glucose, respectively. When utilized as an anode material in lithium-ion batteries, the carbon-coated SnO 2 nanotubes manifests markedly enhanced Li-storage capabilities in terms of specific capacity and cycling stability in comparison with bare SnO 2 nanocrystals. - Graphical abstract: Display Omitted - Highlights: • C-coated SnO 2 nanotubes prepared via facile ZnO-nanorod-templated hydrothermal route. • Unique morphological and structural features toward lithium storage. • Enhanced Li-storage performance in terms of specific capacity and cycling stability

  13. 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

  14. Superconductivity in SnO: a nonmagnetic analog to Fe-based superconductors?

    Science.gov (United States)

    Forthaus, M K; Sengupta, K; Heyer, O; Christensen, N E; Svane, A; Syassen, K; Khomskii, D I; Lorenz, T; Abd-Elmeguid, M M

    2010-10-08

    We discovered that under pressure SnO with α-PbO structure, the same structure as in many Fe-based superconductors, e.g., β-FeSe, undergoes a transition to a superconducting state for p≳6 GPa with a maximum Tc of 1.4 K at p=9.3 GPa. The pressure dependence of Tc reveals a domelike shape and superconductivity disappears for p≳16 GPa. It is further shown from band structure calculations that SnO under pressure exhibits a Fermi surface topology similar to that reported for some Fe-based superconductors and that the nesting between the hole and electron pockets correlates with the change of Tc as a function of pressure.

  15. Superconductivity in SnO: A Nonmagnetic Analog to Fe-Based Superconductors?

    DEFF Research Database (Denmark)

    Forthaus, M. K.; Sengupta, K.; Heyer, O.

    2010-01-01

    We discovered that under pressure SnO with α-PbO structure, the same structure as in many Fe-based superconductors, e.g., β-FeSe, undergoes a transition to a superconducting state for p≳6  GPa with a maximum Tc of 1.4 K at p=9.3  GPa. The pressure dependence of Tc reveals a domelike shape...... and superconductivity disappears for p≳16  GPa. It is further shown from band structure calculations that SnO under pressure exhibits a Fermi surface topology similar to that reported for some Fe-based superconductors and that the nesting between the hole and electron pockets correlates with the change of Tc...

  16. 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.

  17. P-type Cu2O/SnO bilayer thin film transistors processed at low temperatures

    KAUST Repository

    Al-Jawhari, Hala A.

    2013-10-09

    P-type Cu2O/SnO bilayer thin film transistors (TFTs) with tunable performance were fabricated using room temperature sputtered copper and tin oxides. Using Cu2O film as capping layer on top of a SnO film to control its stoichiometry, we have optimized the performance of the resulting bilayer transistor. A transistor with 10 nm/15 nm Cu2O to SnO thickness ratio (25 nm total thickness) showed the best performance using a maximum process temperature of 170 C. The bilayer transistor exhibited p-type behavior with field-effect mobility, on-to-off current ratio, and threshold voltage of 0.66 cm2 V-1 s-1, 1.5×10 2, and -5.2 V, respectively. The advantages of the bilayer structure relative to single layer transistor are discussed. © 2013 American Chemical Society.

  18. 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.

  19. Effect of Annealing Temperature on Gas Sensing Performance of SnO2 Thin Films Prepared by Spray Pyrolysis

    Directory of Open Access Journals (Sweden)

    G. E. PATIL

    2010-12-01

    Full Text Available The effect of variation of annealing temperature on the gas sensing characteristics of SnO2 thin films, which have been prepared by spray pyrolysis on alumina substrate at 350 oC, is investigated systematically for various gases at different operating temperature. The XRD, UV-visible spectroscopy and SEM techniques were employed to establish the structural, optical and morphological characteristics of the materials, resp. The X-ray diffraction results showed an increase in the crystallinity at higher annealing temperature. A high value of sensitivity is obtained for H2S gas at an optimum temperature of 100 oC is improved considerably. A SnO2 gas sensor annealed at 950 oC with sensitivity as high as 24 %, 4 times higher than that of sensor annealed at 550oC, are obtained for 80 ppm of H2S. The degree of crystallinity and grain size calculated from the XRD patterns has been found increasing with annealing temp

  20. Effect of phase interaction on catalytic CO oxidation over the SnO{sub 2}/Al{sub 2}O{sub 3} model catalyst

    Energy Technology Data Exchange (ETDEWEB)

    Chai, Shujing [Collaborative Innovation Center of Chemical Science & Engineering (Tianjin), Tianjin Key Laboratory of Applied Catalysis Science & Technology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300354 (China); The Institute of Seawater Desalination and Miltipurpose Utilization, State Oceanic Administration, Tianjin 300192 (China); Bai, Xueqin; Li, Jing; Liu, Cheng; Ding, Tong; Tian, Ye; Liu, Chang [Collaborative Innovation Center of Chemical Science & Engineering (Tianjin), Tianjin Key Laboratory of Applied Catalysis Science & Technology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300354 (China); Xian, Hui [Tianjin Polytechnic University, School of Computer Science & Software Engineering, Tianjin 300387 (China); Mi, Wenbo [Tianjin Key Laboratory of Low Dimensional Materials Physics and Preparation Technology, Faculty of Science, Tianjin University, Tianjin 300354 (China); Li, Xingang, E-mail: xingang_li@tju.edu.cn [Collaborative Innovation Center of Chemical Science & Engineering (Tianjin), Tianjin Key Laboratory of Applied Catalysis Science & Technology, School of Chemical Engineering & Technology, Tianjin University, Tianjin 300354 (China)

    2017-04-30

    Highlights: • Activity for CO oxidation is greatly enhanced by interaction between SnO{sub 2} and Al{sub 2}O{sub 3}. • Interaction between SnO{sub 2} and Al{sub 2}O{sub 3} phases can generate oxygen vacancies. • Oxygen vacancies play an import role for catalytic CO oxidation. • Sn{sup 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{sub 2}/Al{sub 2}O{sub 3} model catalysts. Our results show that interaction between the Al{sub 2}O{sub 3} and SnO{sub 2} phases results in the significantly improved catalytic activity because of the formation of the oxygen vacancies. The oxygen storage capacity of the SnO{sub 2}/Al{sub 2}O{sub 3} catalyst prepared by the physically mixed method is nearly two times higher than that of the SnO{sub 2}, which probably results from the change of electron concentration on the interface of the SnO{sub 2} and Al{sub 2}O{sub 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{sup 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{sub 2}-based catalysts for CO oxidation follow the Langmuir-Hinshelwood model.

  1. Improved activity of SnO for the photocatalytic oxygen evolution

    Directory of Open Access Journals (Sweden)

    S. Kaizra

    2018-01-01

    Full Text Available SnO prepared by soft chemistry exhibits a black color and semiconducting properties. The X-ray diffraction indicates a tetragonal symmetry (SG: P4/nmm with nano crystallites of an average size of 85 nm. The forbidden band, determined from the diffuse reflectance is found to be 1.46 eV. The electrical conductivity occurs by polaron hopping and follows an Arrhenius type law with activation energy of 0.21 eV, the change in the slope at 526 K is attributed to the oxidation to SnO2. The photo-electrochemical study shows n type conduction with a flat band potential of −0.45 V, close to the photocurrent onset potential (−0.40 V. The electrochemical impedance spectroscopy shows the bulk contribution of SnO (Rb = 1.7 kΩ cm2 and decreases down to 1.89 kΩ cm2 under illumination. The photocatalytic properties have been evaluated for the first time for to the oxygen evolution. The valence band, deriving from Sn2+: 5p orbital with a potential (−0.80 VSCE/5.55 eV, is suitably positioned with respect to O2/H2O level (∼0.6 VSCE, leading to water oxidation under visible light. The best performance occurs at pH ∼ 7 with an oxygen liberation rate of 23 µmol mL h−1 (mg catalyst−1 and a quantum efficiency of 1.2%. An improvement of ∼13% is observed on the system SnO/clay.

  2. A study on 100 MeV O{sup 7+} irradiated SnO{sub 2}/Ag/SnO{sub 2} multilayer as transparent electrode for flat panel display application

    Energy Technology Data Exchange (ETDEWEB)

    Sharma, Vikas [Department of Physics, Malaviya National Institute of Technology, Jaipur 302017 (India); Singh, Satyavir, E-mail: satyavir84@gmail.com [Department of Physics, Malaviya National Institute of Technology, Jaipur 302017 (India); Asokan, K. [Inter-University Accelerator Centre, Aruna Asaf Ali Road, New Delhi 110067 (India); Sachdev, Kanupriya [Department of Physics, Malaviya National Institute of Technology, Jaipur 302017 (India); Materials Research Centre, Malaviya National Institute of Technology, Jaipur 302017 India (India)

    2016-07-15

    The multilayer thin films of SnO{sub 2}/Ag/SnO{sub 2} were deposited using electron-beam and thermal evaporation for flat panel display application. The as-prepared SnO{sub 2}/Ag/SnO{sub 2} specimen was irradiated with 100 MeV O{sup 7+} ions by varying the fluences 1 × 10{sup 12} and 5 × 10{sup 12} ions/cm{sup 2}. The pristine and irradiated films were investigated using XRD, SEM, AFM and Raman to find out modification in the structure and surface morphology of the films. UV–Vis and Hall measurement techniques were used to investigate the optical and electrical properties respectively. It was observed that the roughness of the film after irradiation (for the fluence of 1 × 10{sup 12} ions/cm{sup 2}) ​ decreased to 0.68 nm from 1.6 nm and showed an increase in roughness to 1.35 nm on increasing the fluence to 5 × 10{sup 12} ions/cm{sup 2}. This oxide/metal/oxide structure fulfills the basic requirements of a TCE, like high-transmittance >75% for pristine and >80% for the fluence of 1 × 10{sup 12} ions/cm{sup 2} over a broad spectrum of visible light for practical applications. The multilayer structure shows change in the electrical resistivity from 1.6 × 10{sup −3} Ω cm to 6.3 × 10{sup −3} Ω cm after irradiation.

  3. Moessbauer study of supertransferred hyperfine field of /sup 119/Sn (Sn/sup 4 +/) in Casub(1-x)Srsub(x)MnO/sub 3/

    Energy Technology Data Exchange (ETDEWEB)

    Takano, M [Konan Univ., Kobe (Japan). Faculty of Science; Takeda, Y; Shimada, M; Matsuzawa, T; Shinjo, T

    1975-09-01

    Casub(1-x)Srsub(x)Mnsub(0.99)Snsub(0.01)O/sub 3/(0<=x<=1) with (nearly) cubic perovskite structures were prepared and the magnetic hyperfine fields of /sup 119/Sn (Sn/sup 4 +/) were measured by the Moessbauer effect. The hyperfine fields arise from unpaired s electron spin densities transferred from Mn/sup 4 +/ ions (supertransferred hyperfine interaction). The hyperfine field for a tin ion was found to depend linearly upon the numbers of Ca/sup 2 +/ and Sr/sup 2 +/ ions in the neighboring divalent cation sites, with proportional coefficients having opposite signs. To explain experimental results two kinds of spin transfer processes contributing to the hyperfine field oppositely to each other have been considered, and spin transfer via a divalent cation is emphasized particularly. The hyperfine field at 0 K for Sn/sup 4 +/ in CaMnO/sub 3/ is -75 kOe, while +20 kOe for Sn/sup 4 +/ in SrMnO/sub 3/.

  4. Fabrication of novel SnO2 nanofibers bundle and their optical properties

    International Nuclear Information System (INIS)

    Butt, Faheem K.; Cao, Chuanbao; Khan, Waheed S.; Ali, Zulfiqar; Mahmood, Tariq; Ahmed, R.; Hussain, Sajad; Nabi, Ghulam

    2012-01-01

    Here we report on the synthesis of novel SnO 2 nanofibers bundle (NFB) by using ball milled Fe powders via chemical vapor deposition (CVD). The reaction was carried out in a horizontal tube furnace (HTF) at 1100 °C under Ar flow. The as prepared product was characterized by X-ray diffraction (XRD), scanning electron microscopy, energy dispersive X-ray spectroscopy, transmission electron microscopy, high resolution transmission electron microscopy and selected area electron diffraction (SAED). The microscopy analysis reveals the existence of tubular structure that might be formed by the accumulation of nanofibers. The Raman spectrum reveals that the product is rutile SnO 2 with additional peaks ascribed to defects or oxygen vacancies. Room temperature Photoluminescence (PL) spectrum exhibits three emission bands at 369, 450 and 466.6 nm. Using optical absorbance data, a direct optical bandgap of 3.68 eV was calculated. -- Graphical abstract: Novel SnO 2 nanofibers bundle (NFB) fabricated via CVD method. Field emission scanning electron microscopy image of novel SnO 2 NFB and their room temperature PL emission. Highlights: ► Synthesis of novel SnO 2 nanofibers bundle at 1100 °C under partial flow of Ar gas. ► A VLS mechanism is proposed for the formation of SnO 2 nanofibers. ► The PL spectrum exhibits three emission bands at 369, 450 and 466.6 nm. ► A direct optical bandgap of 3.68 eV was calculated.

  5. Nanoscale Cross-Point Resistive Switching Memory Comprising p-Type SnO Bilayers

    KAUST Repository

    Hota, Mrinal Kanti; Hedhili, Mohamed N.; Wang, Qingxiao; Melnikov, Vasily; Mohammed, Omar F.; Alshareef, Husam N.

    2015-01-01

    Reproducible low-voltage bipolar resistive switching is reported in bilayer structures of p-type SnO films. Specifically, a bilayer homojunction comprising SnOx (oxygen-rich) and SnOy (oxygen-deficient) in nanoscale cross-point (300 × 300 nm2

  6. 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.

  7. Deposition and characterization of single magnetron deposited Fe:SnO{sub x} coatings

    Energy Technology Data Exchange (ETDEWEB)

    Kormunda, Martin, E-mail: martin.kormunda@ujep.cz [J.E. Purkinje University, Faculty of Science, Department of Physics, Ceske mladeze 8, 400 96 Usti nad Labem (Czech Republic); Fischer, Daniel; Hertwig, Andreas; Beck, Uwe [BAM Federal Institute for Materials Research and Testing, Division 6 4 Surface Technologies, Unter den Eichen 44-46, 12203 Berlin (Germany); Sebik, Matej; Pavlik, Jaroslav [J.E. Purkinje University, Faculty of Science, Department of Physics, Ceske mladeze 8, 400 96 Usti nad Labem (Czech Republic); Esser, Norbert [Leibniz-Institut für Analytische Wissenschaften — ISAS e.V., Department Berlin, Schwarzschildstr. 12, 12489 Berlin (Germany)

    2015-11-30

    Coatings deposited by magnetron co-sputtering from a single RF magnetron with a ceramic SnO{sub 2} target with iron inset in argon plasma were studied. The mass spectra of the process identified Sn{sup +} and SnO{sup +} species as the dominant species sputtered from the target, but no SnO{sub 2}{sup +} species were detected. The dominant positive ions in argon plasma are Ar{sup +} species. The only detected negative ions were O{sup −}. Sputtered neutral tin related species were not detected. Iron related species were also not detected because their concentration is below the detection limit. The concentration of iron dopant in the tin oxide coatings was controlled by the RF bias applied on the substrate holder while the discharge pressure also has some influence. The iron concentration was in the range from 0.9 at.% up to 19 at.% increasing with the substrate bias while the sheet resistivity decreases. The stoichiometry ratio of O/(Sn + Fe) in the coatings increased from 1.7 up to 2 in dependence on the substrate bias from floating bias (− 5 V) up to − 120 V of RF self-bias, respectively. The tin in the coatings was mainly bonded in Sn{sup 4+} state and iron was mainly in Fe{sup 2+} state when other tin bonding states were detected only in a small amounts. Iron bonding states in contrary to elemental compositions of the coatings were not influenced by the RF bias applied on the substrate. The coatings showed high transparency in the visible spectral range. However, an increased metallic behavior could be detected by using a higher RF bias for the deposition. The X-ray diffraction patterns and electron microscopy pictures made on the coatings confirmed the presence of an amorphous phase. - Highlights: • RF magnetron sputtering of SnO{sub 2} target with Fe inset in argon investigated by mass spectrometry • Optical properties of Fe doped SnO{sub x} coatings characterized • Analyses of overlapped XPS peaks at a spectrum from Fe doped SnO{sub x} coatings

  8. Reactivity and stability of thallium oxide for fabricating TlSnZnO toward thin-film transistors with high mobility

    Energy Technology Data Exchange (ETDEWEB)

    Kishimoto, Katsushi [Graduate School of Materials Science, Nara Institute of Science and Technology, Nara, 630-0192 (Japan); Nose, Yoshitaro [Department of Materials Science and Engineering, Kyoto University, Kyoto, 606-8501 (Japan); Ishikawa, Yasuaki, E-mail: yishikawa@ms.naist.jp [Graduate School of Materials Science, Nara Institute of Science and Technology, Nara, 630-0192 (Japan); Fujii, Mami N.; Uraoka, Yukiharu [Graduate School of Materials Science, Nara Institute of Science and Technology, Nara, 630-0192 (Japan)

    2016-07-05

    Thermal reaction between thallium oxide (Tl{sub 2}O{sub 3}) and zinc oxide (ZnO), tin oxide (SnO{sub 2}) or indium oxide (In{sub 2}O{sub 3}) annealed at 600 °C for 18 h in the air atmosphere was investigated. From XRD results of 600 °C annealed samples, Tl{sub 2}O{sub 3} had the biggest reactivity compared with ZnO. The EDX results suggest the mechanism in which the thallium atoms scattered and attached uniformly only on ZnO particles. We also analyzed XPS data to compare O 1s bond and Tl 4f bond of as-mixed samples with that of annealed samples, and found that Zn and Sn can contribute in improving Tl and O bonding stability. However, the affinity of In for Tl is weaker than that of Zn or Sn. Finally, we prepared the samples mixed with ZnO, SnO{sub 2}, and Tl{sub 2}O{sub 3} powder and the samples mixed with Zn{sub 2}SnO{sub 4} and Tl{sub 2}O{sub 3} powder annealed at 600 °C for 18 h. Results show that Zn{sub 2}SnO{sub 4} has the same or more reactivity than SnO{sub 2} and ZnO mixed particle despite of the more stable and sufficient dispersion of Zn and Sn atoms. More stable TlSnZnO can be fabricated from Zn{sub 2}SnO{sub 4} + Tl{sub 2}O{sub 3} powder by suitable thermal processes. It is expected that TlSnZnO sputtering target can be fabricated by suitable calcination. - Highlights: • Thermal reaction of Tl{sub 2}O{sub 3} and ZnO, SnO or In{sub 2}O{sub 3} were investigate. • It is found that Tl{sub 2}O{sub 3} is reactive with ZnO rather than SnO or In{sub 2}O{sub 3}. • Two-step annealing process is promising route for forming TlSnZnO tablet.

  9. 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

  10. Nanostructured SnO{sub 2} encapsulated guar-gum hybrid nanocomposites for electrocatalytic determination of hydrazine

    Energy Technology Data Exchange (ETDEWEB)

    Malik, Priya [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India); Srivastava, Manish [Department of Physics & Astrophysics, University of Delhi, Delhi 110007 (India); Verma, Ranjana [Solar Energy Material Laboratory, Department of Energy, Tezpur University, Tezpur, Assam 784 028 (India); Kumar, Manish [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India); Kumar, D., E-mail: dkumar@dce.ac.in [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India); Singh, Jay, E-mail: jay_singh143@yahoo.co.in [Department of Applied Chemistry & Polymer Technology, Delhi Technological University, Shahbad Daulatpur, Main Bawana Road, Delhi 110042 (India)

    2016-01-01

    The present article deals with synthesis of sol–gel derived tin dioxide (SnO{sub 2}) nanoparticles encapsulated in to guar gum (GG) biopolymer as the organic–inorganic hybrid materials for the determination of hydrazine. The organic–inorganic hybrid combines the perfunctory strength offered by the inorganic SnO{sub 2} nanoparticles with flexible binding sites provided by the organic biopolymer (GG) solution by the ultrasonication. The phase identification, crystalline size, surface morphology and optical properties of prepared SnO{sub 2} and SnO{sub 2}-GG nanocomposites has been investigated through FT-IR, XRD, SEM, AFM, TEM, UV–Vis, and PL techniques. The colloidal solution of SnO{sub 2} and GG is electrophoretically deposited (EPD) onto the indium tin-oxide (ITO) glass substrate and studied for the electrooxidation of hydrazine. Under the optimized experimental conditions, the linearity between the current response and the hydrazine concentration has been obtained in the range of 2–22 mM, with a low detection limit of 2.76 mM and a high sensitivity of 5.72 μA cm{sup −2}. Based on the linear increase in amperometric current, a sensitive hydrazine electrochemical sensor is constructed. The proposed SnO{sub 2}-GG/ITO electrode shows a good response time (35 s), reproducibility, and long-term stability. The obtained results suggest that SnO{sub 2}-GG nanocomposites electrode provides a favorable sensing platform for the electrochemical studies. In addition, the cyclic voltammetry (CV) studies are used to evaluate the kinetic parameters. - Graphical abstract: Synthesis of sol–gel derived tin dioxide (SnO{sub 2}) nanoparticles grafted in to gaur gum (GG) organic–inorganic hybrid nanocomposite for determination of hydrazine (HZ). Under optimized experimental conditions, SnO{sub 2}-GG/ITO electrode shows, linearity 2–22 mM, and detection limit 2.769 mM with high sensitivity of 5.72 μA cm{sup −2}. The results clearly suggest that SnO{sub 2}-GG

  11. 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).

  12. Transparent p-type SnO nanowires with unprecedented hole mobility among oxide semiconductors

    KAUST Repository

    Caraveo-Frescas, J. A.

    2013-11-25

    p-type tin monoxide (SnO) nanowire field-effect transistors with stable enhancement mode behavior and record performance are demonstrated at 160 °C. The nanowire transistors exhibit the highest field-effect hole mobility (10.83 cm2 V−1 s−1) of any p-type oxide semiconductor processed at similar temperature. Compared to thin film transistors, the SnO nanowire transistors exhibit five times higher mobility and one order of magnitude lower subthreshold swing. The SnO nanowire transistors show three times lower threshold voltages (−1 V) than the best reported SnO thin film transistors and fifteen times smaller than p-type Cu 2O nanowire transistors. Gate dielectric and process temperature are critical to achieving such performance.

  13. 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.

  14. 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.

  15. Photocatalytic degradation of C. I. Reactive Red 24 solution with K₆SiW₁₁O₃₉Sn(II.).

    Science.gov (United States)

    Guo, Guixiang; Zhu, Xiuhua; Shi, Fuyou; Wang, Anning; Wang, Wei; Mu, Jun; Wan, Quanli; Zhang, Rong

    2013-12-01

    Environmental friendly materials, K6SiW11O39Sn (SiWSn), was synthesized. SiWSn photocatalytic decomposition of C. I. Reactive Red 24 (RR24) with the UV-lamp (253.7 nm, 20 W), Xenon lamp filtered less than 390 nm light (500 W) and sun light was investigated. The results showed that RR24 solution could be effectively decolorized with the SiWSn photocatalyst. The photocatalytic degradation efficiency of RR24 with SiWSn was affected by the initial concentration of RR2 solution, the amount of SiWSn and the photolysis time. It is demonstrated that the process of photodegradation of RR24 with SiWSn is a pesudo first-order reaction, which can be described by Langmuir-Hinshelwood equation. Hydroxyl radicals and holes are both the main oxidants in the photocatalytic reaction of RR24 with SiWSn. Copyright © 2013 The Research Centre for Eco-Environmental Sciences, Chinese Academy of Sciences. Published by Elsevier B.V. All rights reserved.

  16. 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.

  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. Fabrication of hydrogen peroxide biosensor based on Ni doped SnO2 nanoparticles.

    Science.gov (United States)

    Lavanya, N; Radhakrishnan, S; Sekar, C

    2012-01-01

    Ni doped SnO(2) nanoparticles (0-5 wt%) have been prepared by a simple microwave irradiation (2.45 GHz) method. Powder X-ray diffraction (XRD) and transmission electron microscopy (TEM) studies confirmed the formation of rutile structure with space group (P(42)/mnm) and nanocrystalline nature of the products with spherical morphology. Direct electrochemistry of horseradish peroxidase (HRP)/nano-SnO(2) composite has been studied. The immobilized enzyme retained its bioactivity, exhibited a surface confined, reversible one-proton and one-electron transfer reaction, and had good stability, activity and a fast heterogeneous electron transfer rate. A significant enzyme loading (3.374×10(-10) mol cm(-2)) has been obtained on nano-Ni doped SnO(2) as compared to the bare glassy carbon (GC) and nano-SnO(2) modified surfaces. This HRP/nano-Ni-SnO(2) film has been used for sensitive detection of H(2)O(2) by differential pulse voltammetry (DPV), which exhibited a wider linearity range from 1.0×10(-7) to 3.0×10(-4)M (R=0.9897) with a detection limit of 43 nM. The apparent Michaelis-Menten constant (K(M)(app)) of HRP on the nano-Ni-SnO(2) was estimated as 0.221 mM. This excellent performance of the fabricated biosensor is attributed to large surface-to-volume ratio and Ni doping into SnO(2) which facilitate the direct electron transfer between the redox enzyme and the surface of electrode. Copyright © 2012 Elsevier B.V. All rights reserved.

  19. SnO2 anode surface passivation by atomic layer deposited HfO2 improves li-ion battery performance

    KAUST Repository

    Yesibolati, Nulati

    2014-03-14

    For the first time, it is demonstrated that nanoscale HfO2 surface passivation layers formed by atomic layer deposition (ALD) significantly improve the performance of Li ion batteries with SnO2-based anodes. Specifically, the measured battery capacity at a current density of 150 mAg -1 after 100 cycles is 548 and 853 mAhg-1 for the uncoated and HfO2-coated anodes, respectively. Material analysis reveals that the HfO2 layers are amorphous in nature and conformably coat the SnO2-based anodes. In addition, the analysis reveals that ALD HfO2 not only protects the SnO2-based anodes from irreversible reactions with the electrolyte and buffers its volume change, but also chemically interacts with the SnO2 anodes to increase battery capacity, despite the fact that HfO2 is itself electrochemically inactive. The amorphous nature of HfO2 is an important factor in explaining its behavior, as it still allows sufficient Li diffusion for an efficient anode lithiation/delithiation process to occur, leading to higher battery capacity. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. A novel snowflake-like SnO2 hierarchical architecture with superior gas sensing properties

    Science.gov (United States)

    Li, Yanqiong

    2018-02-01

    Snowflake-like SnO2 hierarchical architecture has been synthesized via a facile hydrothermal method and followed by calcination. The SnO2 hierarchical structures are assembled with thin nanoflakes blocks, which look like snowflake shape. A possible mechanism for the formation of the SnO2 hierarchical structures is speculated. Moreover, gas sensing tests show that the sensor based on snowflake-like SnO2 architectures exhibited excellent gas sensing properties. The enhancement may be attributed to its unique structures, in which the porous feature on the snowflake surface could further increase the active surface area of the materials and provide facile pathways for the target gas.

  1. Hybrid molecular beam epitaxy for the growth of stoichiometric BaSnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Prakash, Abhinav, E-mail: praka019@umn.edu; Dewey, John; Yun, Hwanhui; Jeong, Jong Seok; Mkhoyan, K. Andre; Jalan, Bharat, E-mail: bjalan@umn.edu [Department of Chemical Engineering and Materials Science, University of Minnesota, Minneapolis, Minnesota 55455 (United States)

    2015-11-15

    Owing to its high room-temperature electron mobility and wide bandgap, BaSnO{sub 3} has recently become of significant interest for potential room-temperature oxide electronics. A hybrid molecular beam epitaxy (MBE) approach for the growth of high-quality BaSnO{sub 3} films is developed in this work. This approach employs hexamethylditin as a chemical precursor for tin, an effusion cell for barium, and a radio frequency plasma source for oxygen. BaSnO{sub 3} films were thus grown on SrTiO{sub 3} (001) and LaAlO{sub 3} (001) substrates. Growth conditions for stoichiometric BaSnO{sub 3} were identified. Reflection high-energy electron diffraction (RHEED) intensity oscillations, characteristic of a layer-by-layer growth mode were observed. A critical thickness of ∼1 nm for strain relaxation was determined for films grown on SrTiO{sub 3} using in situ RHEED. Scanning transmission electron microscopy combined with electron energy-loss spectroscopy and energy dispersive x-ray spectroscopy confirmed the cube-on-cube epitaxy and composition. The importance of precursor chemistry is discussed in the context of the MBE growth of BaSnO{sub 3}.

  2. 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.

  3. Structural and electrochemical properties of SnO nanoflowers as an anode material for lithium ion batteries

    International Nuclear Information System (INIS)

    Iqbal, M. Zubair; Wang, Fengping; Zhao, Hailei; Rafique, M. Yasir; Wang, Jie; Li, Quanshui

    2012-01-01

    Graphical abstract: -- Novel self-assembled highly hierarchical SnO nanoflowers with acute edge petals have been successfully synthesized by a template-free hydrothermal growth method using SnCl 2 ·2H 2 O and KOH as precursors. Field emission scanning electron microscopy results show that the flower-like SnO architectureis in the range 4–7 μm. Furthermore, Raman modes at A 1g = 212 and B 1g = 114 cm −1 further testify to the existence of nanotetragonal phase SnO. The electrochemical results suggest that synthesized SnO nanoflowers are a promising anode material for lithium ion batteries.

  4. Structure and optical properties of [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub m}

    Energy Technology Data Exchange (ETDEWEB)

    Eichhorn, Simon; Mader, Werner, E-mail: mader@uni-bonn.de

    2016-01-15

    Compounds of [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub 1} (x≤0.22) and [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub 2} (x≤0.42) were prepared by solid state processing proving a substantial solid solution of Sn in the layered compounds InGaO{sub 3}(ZnO){sub m} (m=1, 2). Single crystal X-ray diffraction of the compounds reveals two In{sup 3+} ions to be substituted by one Sn{sup 4+} and one Zn{sup 2+} at the octahedral layer preserving the average charge of +3 at these sites. The substitution does not lead to an ordering of the ions but proves for the first time that the octahedral site can be occupied by different ions while all characteristics of the layered structures remain unchanged. Consequences of indium substitution are (i) decrease of the a axis compared to InGaO{sub 3}(ZnO){sub m} according to smaller ionic radii of Sn{sup 4+} and Zn{sup 2+} compared to In{sup 3+} and (ii) shift of the optical band gap to higher energies shown by UV–vis measurements. - Graphical abstract: Substitution limits of indium in InGaO{sub 3}(ZnO){sub m} (IGZO) by Sn and Zn are studied for m=1, 2 by single crystal X-ray diffraction and micro-chemical analysis. - Highlights: • New Oxides [In{sub 1−2x}Sn{sub x}Zn{sub x}]GaO{sub 3}(ZnO){sub m} (m=1, 2) with IGZO type structure. • Sn and Zn substitute for In at octahedral sites. • Crystal structures were characterized by single crystal X-ray diffraction. • Optical band gap energies were determined by UV–vis spectroscopy.

  5. Phase transition in Sr8[Al12O24](MoO4)2 aluminate sodalite (SAM)

    International Nuclear Information System (INIS)

    Depmeier, W.; Melzer, R.; Hu, X.

    1993-01-01

    The cubic-tetragonal phase transition at 571 K of the aluminate sodalite Sr 8 [Al 12 O 24 ](MoO 4 ) 2 (SAM) has ben studied by following the position of the (pseudo-)cubic {400} reflections as a function of temperature. The high resolution of the synchrotron powder diffraction experiment allowed the temperature dependencies to be followed with good precision. The tetragonal a lattice parameter appears to be a linear extrapolation of the cubic one, with only a small upward shift at the transition, whereas the c parameter decreases strongly below 571 K. These observations can be explained by a model which assumes the superposition of a ferroelastic strain component, and a volume strain component. The volume strain can be rationalized as being the result of a 'shearing' of the sodalite framework. Causes and consequences of the 'shearing' in relation to the sodalite framework are discussed. The weakly first-order transition is nearly tricritical; power-law exponents seem to be influenced by defects. The thermal expansion of the cubic lattice parameter, as well as of the tetragonal a axis, is nearly linear. The linear thermal-expansion coefficient α is 8.6(4)x10 -6 K -1 . The tetragonal c axis also expands linearly between room temperature and about Tc-100 K with practically the same coefficient, but behaves non-linearly nearer to the transition temperature. (orig.)

  6. {sup 119}Sn Mössbauer studies on ferromagnetic and photocatalytic Sn–TiO{sub 2} nanocrystals

    Energy Technology Data Exchange (ETDEWEB)

    Ganeshraja, Ayyakannu Sundaram [Dalian Institute of Chemical Physics, Chinese Academy of Science, Mössbauer Effect Data Center (China); Nomura, Kiyoshi [Tokyo University of Science, Photocatalysis International Research Center (Japan); Wang, Junhu, E-mail: wangjh@dicp.ac.cn [Dalian Institute of Chemical Physics, Chinese Academy of Science, Mössbauer Effect Data Center (China)

    2016-12-15

    Diluted Sn doped TiO{sub 2} nanocrystals (Sn/Ti ratio: x ≤ 1.37 %) were synthesized by a simple hydrothermal method using pure reagents without any surfactant and dispersant material. The XRD of these samples showed an anatase phase, anatase and rutile mixed phases, and a rutile phase of TiO{sub 2} and SnO{sub 2} with the increase of Sn dopant concentrations. {sup 119}Sn Mössbauer spectra gave the broad peaks, which were decomposed into doublets and sextets because almost all these samples showed magnetic hysteresis even at room temperature. The titanium oxides doped with x ≤ 0.12 % showed the relatively large magnetic hysteresis and high photocatalytic activity. Mössbauer spectra of samples doped with x > 0.3 % were analyzed by one doublet and two sextets although the samples showed weak ferromagnetism. Three kinds of Sn species may be distinguished as Sn {sup 4+} substituted TiO{sub 2} and two different magnetic arrangements of Sn doped TiO{sub 2}: one with more oxygen defects and other at the interface of TiO{sub 2} and precipitated SnO{sub 2} containing Ti atoms. The correlation between various amounts of Sn sites and photocatalytic activity and/ or magnetic property was discussed.

  7. Synthesis of hierarchical worm-like SnO2@C aggregates and their enhanced lithium storage properties

    International Nuclear Information System (INIS)

    Wu, Zhen-Guo; Li, Jun-Tao; Zhong, Yan-Jun; Liu, Jie; Guo, Xiao-Dong; Huang, Ling; Zhong, Ben-He; Sun, Shi-Gang

    2015-01-01

    Highlights: • The hierarchical worm-like SnO 2 @C aggregates were synthesized. • The hierarchical worm-like SnO 2 @C unit is assembled by nanowires. • The cycling performances of SnO 2 @C aggregates are improved. • A capacity of 477.0 mA h g −1 at 400 mA g −1 could be obtained after 60 cycles. - Abstract: The present paper reports a synthetic strategy of hierarchical worm-like SnO 2 @C aggregates with enhanced electrochemical performances. Specifically, a glucose-assisted hydrothermal treatment of the intermediate Co–Sn alloy nanoparticles, which were formed by carbothermal reduction of mixed commercial SnO 2 and Co 3 O 4 nanoparticles. The SnO 2 @C sample exhibits enhanced cycling performance in comparison with raw commercial SnO 2 nanoparticles and intermediate Co–Sn alloy nanoparticles when used as anode of lithium ion battery. A stable capacity of 533.6 mA h g −1 at 100 mA g −1 and 477.0 mA h g −1 at 400 mA g −1 remains after 60 cycles. When the current density increases to 1600 mA g −1 , the SnO 2 @C sample still deliver a high capacity of 384.2 mA h g −1 . The superior electrochemical performances could be attributed to the synergistic effect of unique worm-like aggregates structure and carbon surface-layer, which facilitate the electron transportation and buffer the large volume change

  8. SnO2 COMO CATALIZADOR Y SOPORTE DE Ni Y Sn EN LA ALCOHOLISIS DEL ACEITE DE PALMA

    Directory of Open Access Journals (Sweden)

    CARLOS E. ARARAT

    2011-01-01

    Full Text Available El óxido de estaño en forma de SnO2 (casiterita ha sido usado como catalizador en diferentes procesos de interés de la industria química, tales como la de deshidrogenación, cracking, isomerización y oxidación de hidrocarburos. En este trabajo se estudió la aplicación de SnO2 como catalizador y como soporte de especies de níquel y estaño, en la alcohólisis del aceite de palma. La obtención del SnO2 se realizó por el método de precipitación y la incorporación de níquel y estaño, al soporte, por el método de impregnación. Se determinó que el SnO2 presentaba una mayor actividad frente a la reacción de alcohólisis en comparación con otros óxidos, tal como el MgO, y que esta actividad era afectada por la adición de níquel y estaño en su superficie. Se utilizó cromatografía de gases CG para el seguimiento de las reacciones, así como la espectroscopia FTIR para realizar el análisis de los productos obtenidos después del proceso. Los catalizadores fueron analizados por DRX para la determinación de las fases cristalinas presentes y del análisis de área superficial, volumen y tamaño de poro, para determinar las propiedades texturales de los catalizadores.

  9. Facile sonochemical synthesis of Zn2SnO4-V2O5 nanocomposite as an effective photocatalyst for degradation of Eosin Yellow.

    Science.gov (United States)

    Ramasamy Raja, V; Rosaline, D Rani; Suganthi, A; Rajarajan, M

    2018-06-01

    This study presents a novel method for the preparation of Zn 2 SnO 4 /V 2 O 5 nanocomposites via a sonochemical aqueous route. This method is mild, convenient, cheap and efficient. The as prepared samples were characterized by XRD, SEM, EDAX, TEM, BET, FT-IR and UV-DRS spectra. DRS spectrum shows the adsorption edge of Zn 2 SnO 4 -V 2 O 5 in visible region of spectrum. The structural and morphological features of the as synthesized Zn 2 SnO 4 -V 2 O 5 nanocomposites have been observed using both scanning and transmission electron microscopy. BET surface area analysis inferred that the prepared hetero-junctions are meso-porous in nature. The photocatalytic activity of Zn 2 SnO 4 -V 2 O 5 nanocomposites for the degradation of Eosin Yellow (EY) dye under visible light was investigated in detail. 3% Zn 2 SnO 4 -V 2 O 5 nanocomposite exhibited the highest photocatalytic performance (92% of EY degradation) when compared with 2% Zn 2 SnO 4 -V 2 O 5 and 5% Zn 2 SnO 4 -V 2 O 5 . The adsorption of Eosin Yellow followed the pseudo-first order kinetic model. Simultaneously, high stability of the sample was also investigated by four successive photodegradation of EY under visible light. The relationship between photocatalytic activity and the structure of 3% Zn 2 SnO 4 -V 2 O 5 nanocomposite is discussed, and possible reaction mechanisms are also proposed. Therefore, the facile sonochemical preparation process provides some insight into the application of Zn 2 SnO 4 -V 2 O 5 nanocomposites in photocatalytic degradation of organic pollutants. Copyright © 2018. Published by Elsevier B.V.

  10. Cathodoluminescence study of SnO{sub 2} powders aimed for gas sensor applications

    Energy Technology Data Exchange (ETDEWEB)

    Korotcenkov, G. [Technical University of Moldova, Chisinau (Moldova, Republic of)]. E-mail: ghkoro@yahoo.com; Nazarov, M. [Technical University of Moldova, Chisinau (Moldova, Republic of); Zamoryanskaya, M.V. [A.F. Ioffe Physical Technical Institute, RAS, St. Petersburg, Russia (Russian Federation); Ivanov, M. [Technical University of Moldova, Chisinau (Moldova, Republic of); Cirera, A. [EME/CERMAE. Dep. Elect., University of Barcelona, Barcelona (Spain); Shimanoe, K. [Kyushu University, Kasuga-shi, Fukuoka (Japan)

    2006-06-15

    In this paper we report on cathodoluminescence (CL) spectra of SnO{sub 2} powders, synthesized using the wet chemical route. The analysis of influence of the modes of calcination (T {sub an}-450-800 deg. C), and doping by both Pd and Pt (0.01-10.0 wt.%) on CL spectra was made. It was found that the measurement of CL spectra could be an effective research method of nanostructured metal oxides, aimed for gas sensor applications. It was established that in nanocrystalline SnO{sub 2} the same system of energy levels, associated with radiative recombination, as in single crystalline and polycrystalline SnO{sub 2}, is retained. It was found that doping by both Pd and Pt modifies the structural properties of SnO{sub 2} grains. Also, there is an optimum doping; near 0.1-0.2 wt.%, at which a maximum intensity of cathodoluminescence is reached. It was concluded that for low concentrations of both Pd and Pt additives in SnO{sub 2} an improvement of the material's crystal structure is promoted, and is associated with a decrease in the non-radiating recombination rate.

  11. Synthesis, structural and luminescent aspect of Tb3+ doped Sr2SnO4 phosphor

    International Nuclear Information System (INIS)

    Taikar, Deepak R.

    2016-01-01

    A novel green emitting, Tb 3+ doped Sr 2 SnO 4 phosphor was synthesized by the co-precipitation method and its photoluminescence characterization was performed. Sr 2 SnO 4 has an ordered tetragonal K 2 NiF 4 -type structure with space group I4/mmm. The structure of Sr 2 SnO 4 consists of SnO 6 octahedra. From the structure of Sr 2 SnO 4 , it was observed that the sites of Sn 4+ ions have inverse symmetry while the Sr 2+ ions have the low symmetry. X-ray powder diffraction (XRD) analysis confirmed the formation of Sr 2 SnO 4 :Tb 3+ . Photoluminescence measurements showed that the phosphor exhibited bright green emission at about 543 nm attributed to 5 D 4 à 7 F 5 transition of Tb 3+ ion under UV excitation. The emission spectra did not exhibit conventional blue emission peaks of Tb 3+ ions due to 5 D 3 → 7 F J transitions in the spectral region 350-470 nm. The excitation spectra indicate that this compound may be useful as a lamp phosphor. (author)

  12. Early stage detection of β→α transition in Sn by Mössbauer spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Skwarek, Agata, E-mail: askwarek@ite.waw.pl [Institute of Electron Technology Cracow Division, Zabłocie 39, 30-701 Kraków (Poland); Zachariasz, Piotr [Institute of Electron Technology Cracow Division, Zabłocie 39, 30-701 Kraków (Poland); Żukrowski, Jan [AGH University of Science and Technology, Academic Center for Materials and Nanotechnology, A. Mickiewicza 30, 30-059 Kraków (Poland); Synkiewicz, Beata; Witek, Krzysztof [Institute of Electron Technology Cracow Division, Zabłocie 39, 30-701 Kraków (Poland)

    2016-10-01

    Mössbauer spectroscopy was used for the early stage detection of the β→α transition (tin pest) in Sn matrix. The results were compared with the data from X-ray diffraction and a variance in the sensitivity for both methods has been proven. Mössbauer spectroscopy is more responsive method than XRD to tin pest finding and with possible detection level of even 1.8%. Furthermore, in reference sample, suspected to be pure α-Sn, large content of white tin (β-Sn), even after 6 years of exposure at sub-zero temperature, has been identified. 48% of α-Sn phase but also 52% of non-transferred β-Sn has been still detectable. - Highlights: • β→α transition (tin pest) could completely disintegrate Sn-rich material. • Early stage detection of β→α transition still exhibits substantial difficulties. • Mössbauer spectroscopy is very sensitive method in detection of β→α transition in Sn matrix. • Different values of Mössbauer-Lamb factors for β and α-Sn allow to detect tin pest at the level of 1.8%.

  13. 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.

  14. 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.

  15. A comparative study of the magnetization in transition metal ion doped CeO2, TiO2 and SnO2 nanoparticles

    Science.gov (United States)

    Apostolov, A. T.; Apostolova, I. N.; Wesselinowa, J. M.

    2018-05-01

    Using the microscopic s-d model taking into account anharmonic spin-phonon interactions we have studied the magnetic properties of Co and Cu ion doped CeO2 and TiO2 nanoparticles and compared them with those of SnO2. By Co-doping there is a maximum in the magnetization M(x) curve for all nanoparticles observed in the most transition metal doped ones. The s-d interaction plays an important role by the decrease of M at higher dopant concentration. We have discussed the magnetization in dependence of different model parameters. By small Cu-ion doping there are some differences. In CeO2M decreases with the Cu-concentration, whereas in TiO2 and SnO2M increases. For higher Cu dopant concentrations M(X) decreases in TiO2 nanoparticles. We obtain room temperature ferromagnetism also in Zn doped CeO2, TiO2 and SnO2 nanoparticles, i.e. in non-transition metal ion doped ones. The different behavior of M in Co and Cu doped nanoparticles is due to a combination effect of multivalent metal ions, oxygen vacancies, different radius of cation dopants, connection between lattice and magnetism, as well as competition between the s-d and d-d ferromagnetic or antiferromagnetic interactions.

  16. Enhanced photoelectrochemical performance of PbS sensitized Sb–SnO{sub 2}/TiO{sub 2} nanotube arrays electrode under visible light illumination

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Jia; Tang, Chengli [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Xu, Hao, E-mail: xuhao@mail.xjtu.edu.cn [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); Yan, Wei, E-mail: yanwei@mail.xjtu.edu.cn [Department of Environmental Science and Engineering, Xi’an Jiaotong University, Xi’an 710049 (China); State Key Laboratory of Multiphase Flow in Power Engineering, Xi’an Jiaotong University, Xi’an 710049 (China)

    2015-06-05

    Highlights: • Sb–SnO{sub 2} is used to modify TiO{sub 2} NTAs by microwave method. • PbS is employed to sensitive Sb–SnO{sub 2}/TiO{sub 2} NTAs by S-SILAR method. • Sb–SnO{sub 2} improves electrons transfer and PbS enhances visible light absorption. • The composite electrode shows enhanced photoelectrochemical properties. • The composite electrode exhibits high hydrogen evolution and high QE. - Abstract: The novel PbS sensitized Sb–SnO{sub 2}/TiO{sub 2} nanotube arrays (NTAs) composite electrode (PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs) was fabricated by microwave combined with sonication-assisted successive ionic layer adsorption and reaction technique (S-SILAR). The obtained electrodes were characterized by field-emission scanning electron microscopy (FE-SEM), energy-dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and UV–Vis diffuse reflectance absorption spectra techniques. Enhanced photocurrent (15.52 mA/cm{sup 2}) of the PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs electrode was observed and can be attributed to the facile photo-generated electrons transfer and enhanced charge separation efficiency. Furthermore, the PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs composite electrode shows a higher H{sub 2} production rate than the Sb–SnO{sub 2}/TiO{sub 2} NTAs electrode and PbS/TiO{sub 2} NTAs electrode. The results indicate that the PbS/Sb–SnO{sub 2}/TiO{sub 2} NTAs electrode is a promising photoanode in visible photocatalytic water splitting.

  17. Dopant-site-dependent scattering by dislocations in epitaxial films of perovskite semiconductor BaSnO{sub 3}

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Useong; Park, Chulkwon; Kim, Rokyeon; Mun, Hyo Sik; Kim, Hoon Min; Kim, Namwook; Yu, Jaejun; Char, Kookrin, E-mail: kchar@phya.snu.ac.kr [Center for Strongly Correlated Materials Research, Department of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of); Ha, Taewoo; Kim, Jae Hoon [Department of Physics, Yonsei University, Seoul 120-749 (Korea, Republic of); Kim, Hyung Joon; Kim, Tai Hoon; Kim, Kee Hoon [Center for Novel States of Complex Materials Research, Department of Physics and Astronomy, Seoul National University, Seoul 151-747 (Korea, Republic of)

    2014-05-01

    We studied the conduction mechanism in Sb-doped BaSnO{sub 3} epitaxial films, and compared its behavior with that of the mechanism of its counterpart, La-doped BaSnO{sub 3}. We found that the electron mobility in BaSnO{sub 3} films was reduced by almost 7 times when the dopant was changed from La to Sb, despite little change in the effective mass of the carriers. This indicates that the scattering rate of conduction electrons in the BaSnO{sub 3} system is strongly affected by the site at which the dopants are located. More importantly, we found that electron scattering by threading dislocations also depends critically on the dopant site. We propose that the large enhancement of scattering by the threading dislocations in Sb-doped BaSnO{sub 3} films is caused by the combination effect of the change in the distribution of Sb impurities in the films, the formation of the Sb impurity clusters near the threading dislocations, and the conduction electron clustering near the Sb impurities.

  18. 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.

  19. Enhancing performances of a resistivity-type hydrogen sensor based on Pd/SnO2/RGO nanocomposites.

    Science.gov (United States)

    Peng, Yitian; Zheng, Lulu; Zou, Kun; Li, Cong

    2017-05-26

    Palladium/tin oxide/reduced graphene oxide (Pd/SnO 2 /RGO) nanocomposites with Pd and SnO 2 crystalline nanoparticles of high density and uniformity coated on RGO have been synthesized by a two-step reduction process. A novel hydrogen (H 2 ) sensor based on Pd/SnO 2 /RGO nanocomposites was fabricated by placing Pd/SnO 2 /RGO nanocomposites onto a pair of gold electrodes. The Pd/SnO 2 /RGO nanocomposite-based sensor exhibited higher responses than Pd/RGO to H 2 because the introduction of SnO 2 nanoparticles enhances H 2 adsorption and forms a P-N junction with RGO. The sensor shows a high response of 55% to 10 000 ppm H 2 , and a low detection limit, fast response, good selectivity and repeatability due to a combination effect of the Pd and SnO 2 nanoparticles. The studies provide a novel strategy for great potential applications of graphene-based gas sensors.

  20. 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.

  1. Enhanced NH{sub 3} gas sensing performance based on electrospun alkaline-earth metals composited SnO{sub 2} nanofibers

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Shuang [Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Key Laboratory of Physical Chemistry, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); Kan, Kan [Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Key Laboratory of Physical Chemistry, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); Daqing Branch, Heilongjiang Academy of Sciences, Daqing 163319 (China); Yang, Ying; Jiang, Chao [Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Key Laboratory of Physical Chemistry, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); Gao, Jun [Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Key Laboratory of Physical Chemistry, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); Department of Chemistry, Harbin Normal University, Harbin 150025 (China); Jing, Liqiang [Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Key Laboratory of Physical Chemistry, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); Shen, Peikang [Department of Physics and Engineering Sun Yat-sen University, Guangzhou 510275 (China); Li, Li, E-mail: llwjjhlju@sina.cn [Key Laboratory of Functional Inorganic Material Chemistry, Ministry of Education, Key Laboratory of Physical Chemistry, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); Key Laboratory of Chemical Engineering Process and Technology for High-efficiency Conversion, School of Chemistry and Material Science, Heilongjiang University, Harbin 150080 (China); and others

    2015-01-05

    Highlights: • The small-sized SnO{sub 2} (5–7 nm) were obtained by adding the alkaline-earth. • Sr-composited SnO{sub 2} nanofibers showed uniform nanotubes structure (Sr/SnO{sub 2}). • Sr/SnO{sub 2} showed an excellent sensing performance to NH{sub 3} at room temperature. - Abstract: One-dimensional alkaline-earth metals composited SnO{sub 2} (Ae/SnO{sub 2}) nanofibres were fabricated via electrospinning technique, followed by thermal treatment at 600 °C for 5 h. Transmission electron microscopy (TEM) studies showed that the nanoparticles size of Ae/SnO{sub 2} was 5–7 nm, which was smaller than the pristine SnO{sub 2} nanorods attached by 20 nm nanoparticles. Moreover, Sr/SnO{sub 2} nanocomposites showed uniform nanotubes structure with the wall thickness of about 30 nm, in which all the nanoparticles were connected to their neighbors by necks. The Sr/SnO{sub 2} nanotubes exhibited an excellent sensing response toward NH{sub 3} gas at room temperature, lower detection limit (10 ppm), faster response time (6 s towards 2000 ppm∼16 s towards 10 ppm) and better reversibility compared to the pristine SnO{sub 2} nanorods. The enhanced sensor performances were attributed to the higher conductivity of the Sr/SnO{sub 2}. Mott–Schottky plots (M–S) and electrochemical impedance spectroscopy (EIS) measurements indicated that the carrier density of Sr/SnO{sub 2} nanotubes was 3 fold of that pristine SnO{sub 2}.

  2. Enhancement of H2-sensing Properties of F-doped SnO2 Sensorby Surface Modification with SiO2

    Directory of Open Access Journals (Sweden)

    S. P. Khatkar

    2006-05-01

    Full Text Available Effects of surface chemical modification with sodium silicate on the gas-sensingproperties of F-doped SnO2 gas sensor designed and fabricated employing micro-electromechanical system (MEMS technology were investigated. Gas sensing properties of thesensor were checked against combustible gases like H2, CO, CH4 and C3H8 at a heatervoltage of 0.7 V. The H2 sensitivity of the surface modified F-doped SnO2 micro sensormarkedly increased and reached S = 175 which was found to be about 40 times more thanthat of unmodified sensor (S = ~ 4.2. The increase in the sensitivity is discussed in terms ofincreased resistivity and reduced permeation of gaseous oxygen into the underlying sensinglayer due to the surface modification of the sensor. The present micro-hydrogen sensor withenhanced sensitivity due to SiO2 incorporation is a low energy consuming portable sensormodule that can be mass-produced using MEMS technology at low cost.

  3. Radiochemical synthesis of a carbon-supported Pt–SnO2 bicomponent nanostructure exhibiting enhanced catalysis of ethanol oxidation

    International Nuclear Information System (INIS)

    Okazaki, Tomohisa; Seino, Satoshi; Nakagawa, Takashi; Kugai, Junichiro; Ohkubo, Yuji; Akita, Tomoki; Nitani, Hiroaki; Yamamoto, Takao A.

    2015-01-01

    Carbon-supported Pt–SnO 2 electrocatalysts with various Sn/Pt molar ratios were prepared by an electron beam irradiation method. These catalysts were composed of metallic Pt particles approximately 5 nm in diameter together with low crystalline SnO 2 . The contact between the Pt and SnO 2 in these materials varied with the amount of dissolved oxygen in the precursor solutions and it was determined that intimate contact between the Pt and SnO 2 significantly enhanced the catalytic activity of these materials during the ethanol oxidation reaction. The mechanism by which the contact varies is discussed based on the radiochemical reduction process. - Highlights: • Ethanol oxidation catalysis was enhanced by Sn-addition, far less than ever reported. • Pt–SnO 2 contact is crucial to the catalysis enhancement, alloying of Sn is not necessary. • Nano-scaled intimate contact between Pt and SnO 2 was directly observed

  4. Hybrid van der Waals SnO/MoS2 Heterojunctions for Thermal and Optical Sensing Applications

    KAUST Repository

    Wang, Zhenwei

    2017-11-10

    Emerging van der Waals heterojunctions (vdWH) containing 2D materials have shown exciting functionalities that surpass those of traditional devices based on bulk materials. In this Communication, a report on the properties of a 2D sulfide/oxide hybrid vdWH based on n-type molybdenum disulfide (MoS2) and p-type tin monoxide (SnO) is presented, with promising rectification, thermal-sensing, and photosensing performance. Specifically, the hybrid SnO/MoS2 vdWH shows static rectification ratio of 2 × 102 with ideality factor of 2.3, and can operate at 100 Hz with good stability. The vdWH shows good temperature stability with reversible and reproducible current levels up to 110 °C, indicating its potential for thermal sensing applications. The sensitivity of current variation is calculated to be 0.0144 dec °C−1. Finally, maximum responsivity of 8.17 mA W−1 and external quantum efficiency of 2.14% have been achieved in photovoltaic measurements. The results suggest that MoS2–SnO hybrid vdWH are promising for various sensing applications.

  5. SiO{sub 2}@SnO{sub 2}/graphene composite with a coating and hierarchical structure as high performance anode material for lithium ion battery

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Xingfa; Zhang, Haiyan, E-mail: hyzhang@gdut.edu.cn; Chen, Yiming; Li, Na; Li, Yunyong; Liu, Liying

    2016-08-25

    In order to ease the agglomeration and huge volume change of SnO{sub 2} particles, SnO{sub 2} nanoparticles were usually anchored on reduced graphene oxide (rGO) and used as anode materials for lithium ion batteries. Unfortunately, graphene sheets tended to overlap with adjacent ones and SnO{sub 2} nanoparticles still suffered from agglomeration and huge volume changes to some extent. In this paper, a composite SiO{sub 2}@SnO{sub 2}/rGO with coating and hierarchical structure was synthesized by a facile hydrothermal method. SnO{sub 2} nanoparticles mono-dispersed on the surface of rGO sheets and SiO{sub 2} spheres, while the SiO{sub 2}@SnO{sub 2} spheres were imbedded in the layers of rGO, which was in favor of alleviating the overlapping of graphene sheets and could make large spacious room to accommodate the huge volume changes of SnO{sub 2} nanoparticles. SiO{sub 2}@SnO{sub 2}/rGO composite also displayed good electrochemical performance. In the first charge/discharge cycle, the SiO{sub 2}@SnO{sub 2}/rGO electrode exhibited a large discharge capacity of 1548 mA h g{sup −1} at a current density of 100 mA g{sup −1} and it still retained a discharge capacity of about 600 mA h g{sup −1} after 100 cycles. - Highlights: • Anodes fabricated by using activated carbon have the highest fracture strength. • SnO{sub 2} nanoparticles are mono-dispersed on the surface of rGO sheets and SiO{sub 2} spheres. • The hierarchical structure SiO{sub 2}@SnO{sub 2}/rGO shows a good electrochemical performance.

  6. Synthesis of La2O3 doped Zn2SnO4 hollow fibers by electrospinning method and application in detecting of acetone

    Science.gov (United States)

    Yang, H. M.; Ma, S. Y.; Yang, G. J.; Chen, Q.; Zeng, Q. Z.; Ge, Q.; Ma, L.; Tie, Y.

    2017-12-01

    Hollow porous pure and La2O3 doped Zn2SnO4 fibers were synthesized via single capillary electrospinning technology and used for obtaining of gas sensors. The as-prepared samples were characterized by microscopy, Brunauer-Emmett-Teller, X-ray photoelectron spectroscopy and UV-vis absorption spectra. The newly obtained gas sensors were investigated for acetone detection. Compared with pure Zn2SnO4 hollow fibers, the La2O3 doped Zn2SnO4 hollow fibers not only exhibited perfect sensing performance toward acetone with excellent selectivity, high response and fast response/recovery capability (7 s for adsorption and 9 s for desorption), but also the operating temperature was reduced from 240 °C to 200 °C. These results demonstrated that the special hollow porous La doped Zn2SnO4 fibers structures were used as the sensing material for fabricating high performance acetone sensors. The acetone sensing mechanism of La2O3 doped Zn2SnO4 hollow fibers was discussed too.

  7. Controlling the Performance of P-type Cu2O/SnO Bilayer Thin-Film Transistors by Adjusting the Thickness of the Copper Oxide Layer

    KAUST Repository

    Al-Jawhari, Hala A.

    2014-11-11

    The effect of copper oxide layer thickness on the performance of Cu2O/SnO bilayer thin-film transistors was investigated. By using sputtered Cu2O films produced at an oxygen partial pressure, Opp, of 10% as the upper layer and 3% Opp SnO films as the lower layer we built a matrix of bottom-gate Cu2O/SnO bilayer thin-film transistors of different thickness. We found that the thickness of the Cu2O layer is of major importance in oxidation of the SnO layer underneath. The thicker the Cu2O layer, the more the underlying SnO layer is oxidized, and, hence, the more transistor mobility is enhanced at a specific temperature. Both device performance and the annealing temperature required could be adjusted by controlling the thickness of each layer of Cu2O/SnO bilayer thin-film transistors.

  8. Al-doped SnO2 nanocrystals from hydrothermal systems

    International Nuclear Information System (INIS)

    Jin Haiying; Xu Yaohua; Pang Guangsheng; Dong Wenjun; Wan Qiang; Sun Yan; Feng Shouhua

    2004-01-01

    Nanoparticles of Al-doped SnO 2 have been hydrothermally synthesized. The influences of the hydrothermal reaction time, the molar ratio of Sn/Al as well as the pH value of the solution have been studied. During the hydrothermal synthesis, the particle's core is rich in Sn and the surface is rich in Al. The Al-rich surface prevents the particles from further growing up either in the hydrothermal condition or during the calcination at 600 deg. C for a short period of time. The optimal hydrothermal synthesis condition of the nanoparticles is pH 5, Sn/Al=4:1 and 12 h at 160 deg. C. The products have been studied by XRD, TEM and 27 Al solid-state NMR

  9. 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.

  10. Correlation between SnO{sub 2} nanocrystals and optical properties of Eu{sup 3+} ions in SiO{sub 2} matrix: Relation of crystallinity, composition, and photoluminescence

    Energy Technology Data Exchange (ETDEWEB)

    Thanh, Bui Quang [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); Ha, Ngo Ngoc, E-mail: hann@itims.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); Khiem, Tran Ngoc, E-mail: khiem@itims.edu.vn [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); Chien, Nguyen Duc [International Training Institute for Materials Science (ITIMS), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam); School of Engineering Physics (SEP), Hanoi University of Science and Technology (HUST), No.1 Dai Co Viet, Hanoi (Viet Nam)

    2015-07-15

    We report characteristics and optical properties of Eu{sup 3+}-doped SnO{sub 2} nanocrystals dispersed in SiO{sub 2} matrix. Samples are prepared by the sol–gel method. Crystallinity of SnO{sub 2} nanocrystals is examined by X-ray diffraction experiments. At annealing temperatures from 900 to 1200 °C, we observe the formation of single tetragonal rutile structure of SnO{sub 2} nanocrystals. Average sizes of SnO{sub 2} nanocrystals within 3–7 nm are estimated by Debye–Scherrer equation. Intense photoluminescent spectra of Eu{sup 3+} ions consist of a series of resolved emission bands within 570–645 nm, which are varied with different sample-preparation conditions. We show the efficient excitation process of Eu{sup 3+} ions through SnO{sub 2} nanocrystals in the materials. Microscopic structure of SnO{sub 2} nanoparticles and optical properties of Eu{sup 3+} ions are also presented and discussed. - Highlights: • Thin layers of Eu{sup 3+} doped SnO{sub 2} nanocrystals dispersed in SiO{sub 2} were prepared by sol-gel method and spin-coating process. • Formation of single-phase tetragonal rutile structure of SnO{sub 2} nanocrystals and highly efficient optical excitation of the Eu{sup 3+} dopants were exhibited. • Relations of the crystallinity and composition of SnO{sub 2} and optical properties of Eu{sup 3+} dopants were comprehensively investigated and presented. • Allocations of major optically-active Eu{sup 3+} ions in the materials were deduced from their emission bands.

  11. A facile one-pot method to Au–SnO2-graphene ternary hybrid

    International Nuclear Information System (INIS)

    Xu, Diou; Li, Xiaotian; Zhang, Dawei

    2014-01-01

    In this article, we propose a facile one-pot route for synthesizing Au–SnO 2 -graphene ternary hybrid. In the system, SnCl 2 not only as the precursor of SnO 2 , but also is employed as reducing agent for the effective reduction of both GO and HAuCl 4 to graphene and Au nanoparticles, respectively. The obtained Au–SnO 2 -graphene hybrid materials are characterized by atomic force microscopy, transmission electron microscopy, X-ray diffraction, Raman spectrum, X-ray photo-electron spectroscopy, and thermal gravimetric analysis. It is found that the content of Au nanoparticles decorated on the surface of graphene can be simply adjusted by changing the amount of HAuCl 4 used in the synthesis process

  12. Sn-doped β-Ga2O3 nanowires deposited by radio frequency powder sputtering

    Science.gov (United States)

    Lee, Su Yong; Kang, Hyon Chol

    2018-01-01

    We report the synthesis and characterization of Sn-doped β-Ga2O3 nanowires (NWs) deposited using radio frequency powder sputtering. The growth sequence of Sn-doped β-Ga2O3 NWs is similar to that of the undoped β-Ga2O3 NWs. Self-assembled Ga clusters act as seeds for initiating the growth of Sn-doped β-Ga2O3 NWs through a vapor-liquid-solid process, while Sn atoms are incorporated into the trunk of NWs uniformly. Different from the straight shape of undoped NWs, the conical shape of NWs is observed, which is attributed to the change in supersaturation conditions and the diffusion of the catalyst tip and reaction species.

  13. Performance PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SbO{sub 2} for the electro-oxidation of ethanol, prepared by an alcohol-reduction process; Desempenho de eletrocatalisadores PtSnRh suportados em carbono-Sb{sub 2}O{sub 5}.SnO{sub 2} para a oxidacao eletroquimica do etanol, preparados pelo metodo de reducao por alcool

    Energy Technology Data Exchange (ETDEWEB)

    Castro, Jose Carlos

    2013-07-01

    PtSnRh electrocatalysts supported on carbon-Sb{sub 2}O{sub 5}.SnO{sub 2}, with metal loading of 20 wt%, were prepared by an alcohol-reduction process, using H{sub 2}PtCl{sub 6}.6H{sub 2}O (Aldrich), RhCl{sub 3}.xH{sub 2}O (Aldrich) and SnCl{sub 2}.2H{sub 2}O (Aldrich), as source of metals; Sb{sub 2}O{sub 5}.SnO{sub 2} (ATO) and carbon Vulcan XC72, as support; and ethylene glycol as reducing agent. The electrocatalysts obtained were characterized physically by X-ray diffraction (XRD) and transmission electron microscopy (TEM). The diffractograms showed which PtSnRh/C-ATO electrocatalysts had FCC structure of Pt and Pt alloys, besides several peaks associated with SnO{sub 2} and ATO. The average sizes of crystallites were between 2 and 4 nm. TEM micrographs showed a good distribution of the nanoparticles on the support. The average sizes of particles were between 2 and 3 nm, with good agreement for the average size of the crystallites. The performances of the electrocatalysts were analyzed by electrochemical techniques and in real conditions of operation using single direct ethanol fuel cell. In the chronoamperometry at 50 deg C, the electrocatalysts with carbon (85 wt%) and ATO (15 wt%) support, showed the best activity, and the atomic proportions which achieved the best results were PtSnRh(70:25:05) e (90:05:05). PtSnRh(70:25:05)/85C+15ATO electrocatalysts showed the best performance in a direct ethanol fuel cell. (author)

  14. Influence of the Si content on the microstructure and mechanical properties of Ti–Ni–Cu–Si–Sn nanocomposite alloys

    International Nuclear Information System (INIS)

    Fornell, J.; Van Steenberge, N.; Suriñach, S.; Baró, M.D.; Sort, J.

    2012-01-01

    Highlights: ► We study the effects of Si addition of Ti–Ni–Cu–Si–Sn alloy. ► The microstructure evolution is correlated with the obtained mechanical and elastic properties. ► Higher Young's modulus and larger hardness values are obtained in samples with higher Si contents. - Abstract: (Ti 48 Ni 32 Cu 8 Si 8 Sn 4 ) 100−x Si x (x = 0, 2, 4 and 6) alloys were prepared by levitation melting mixtures of the high purity elements in an Ar atmosphere. Rods of 3 mm in diameter were obtained from the melt by copper mould casting. The effects of Si addition on the microstructure, elastic and mechanical properties of the Ti 48 Ni 32 Cu 8 Si 8 Sn 4 alloy were investigated by scanning electron microscopy, X-ray diffraction, acoustic measurements and nanoindentation. The main phases composing the Ti 48 Ni 32 Cu 8 Si 8 Sn 4 alloy are B2 NiTi, B19′ NiTi and tetragonal Ti 2 Ni. Additional phases, like Ti 5 Si 3 or Ni 2 Ti 2 Si, become clearly visible in samples with higher Si contents. The microstructure evolution is correlated with the obtained mechanical and elastic properties. These alloys exhibit very high hardness values, which increase with the Si content, from 9 GPa (for x = 0) to around 10.5 GPa (for x = 6). The Young's modulus of Ti 48 Ni 32 Cu 8 Si 8 Sn 4 (around 115 GPa) also increases significantly with Si addition, up to 160 GPa for x = 6.

  15. Determination of 11 trace elements in U3O8 CRMs by ICP-AES

    International Nuclear Information System (INIS)

    Liu Husheng

    1994-01-01

    The TBP extractant-containing resin and extraction chromatography technique were used to separate 11 trace elements in U 3 O 8 CRMs. The sample was separated at a flow rate of 0.5 mL/min with 3 mol/L HNO 3 as medium. A model 975 ICP direct reading spectrometer was used to determine the trace elements of Ca, Cd, Cr, Cu, Fe, Mg, Mn, Mo, Ni, Pb and Sn in U 3 O 8 CRMs. The lowest quantitatively determinable concentration of impurities in U 3 O 8 CRMs are 0.02-1.6 μg/g. The RSD is less than 10%. The proposed method provides excellent and accurate analytical data for the U 3 O 8 samples prepared as certified reference materials (CRMs)

  16. Design of binary SnO_2-CuO nanocomposite for efficient photocatalytic degradation of malachite green dye

    International Nuclear Information System (INIS)

    Kumar, Aniket; Rout, Lipeeka; Achary, L. Satish Kumar; Mohanty, Anurag; Marpally, Jyoshna; Chand, Pradyumna Kumar; Dash, Priyabrat

    2016-01-01

    Semiconductor mediated photocatalysis has got enormous consideration as it has shown immense potential in addressing the overall energy and environmental issues. To overcome the earlier drawbacks concerning quick charge recombination and limited visible-light absorption of semiconductor photocatalysts, numerous methods have been produced in the past couple of decades and the most broadly utilized one is to develop the photocatalytic heterojunctions. In our work, a series of SnO_2-CuO nanocomposites of different compositions were synthesized by a combustion method and have been investigated in detail by various characterization techniques, such as wide angle X-ray diffraction (XRD), UV-vis spectroscopy, transmission electron microscopy (TEM), and field emission scanning electron microscopy (FE-SEM). The results revealed that the crystal structure and optical properties of the nanocomposites were almost same for all the compositions. FE-SEM images showed that the shape of SnO_2-CuO was spherical in nature and the 1: 1 Sn/Cu sample had a well-proportioned morphology. The malachite green dye was used for the photocatalytic studies in a photoreactor and monitored with a UV-visible spectrometer for different composition ratio of metal (Sn: Cu) such as 1:1, 1:2, 2:1, 1:0.5 and 0.5:1. The 1:1 ratio nanocomposite showed excellent photocatalytic degradation of 96 % compared to pure SnO_2 and CuO. The mechanism of degradation and charge separation ability of the nanocomposite are also explored using photocurrent measurement study.

  17. One-Pot Synthesis of Carbon-Coated SnO 2 Nanocolloids with Improved Reversible Lithium Storage Properties

    KAUST Repository

    Lou, Xiong Wen

    2009-07-14

    We report a simple glucose-mediated hydrothermal method for gram-scale synthesis of nearly monodisperse hybrid SnO 2 nanoparticles. Glucose is found to play the dual role of facilitating rapid precipitation of polycrystalline SnO 2 nanocolloids and in creating a uniform, glucose-derived, carbon-rich polysaccharide (GCP) coating on the SnO 2 nanocores. The thickness of the GCP coating can be facilely manipulated by varying glucose concentration in the synthesis medium. Carbon-coated SnO 2 nanocolloids obtained after carbonization of the GCP coating exhibit significantly enhanced cycling performance for lithium storage. Specifically, we find that a capacity of ca. 440 mA h/g can be obtained after more than 100 charge/discharge cycles at a current density of 300 mA/g in hybrid SnO 2-carbon electrodes containing as much as 1/3 of their mass in the low-activity carbon shell. By reducing the SnO 2-carbon particles with H 2, we demonstrate a simple route to carbon-coated Sn nanospheres. Lithium storage properties of the latter materials are also reported. Our results suggest that large initial irreversible losses in these materials are caused not only by the initial, presumably irreversible, reduction of SnO 2 as generally perceived in the field, but also by the formation of the solid electrolyte interface (SEI). © 2009 American Chemical Society.

  18. Laser induced forward transfer of SnO2 for sensing applications using different precursors systems

    Science.gov (United States)

    Mattle, Thomas; Hintennach, Andreas; Lippert, Thomas; Wokaun, Alexander

    2013-02-01

    This paper presents the transfer of SnO2 by laser induced forward transfer (LIFT) for gas sensor applications. Different donor substrates of SnO2 with and without triazene polymer (TP) as a dynamic release layer were prepared. Transferring these films under different conditions were evaluated by optical microscopy and functionality. Transfers of sputtered SnO2 films do not lead to satisfactory results and transfers of SnO2 nanoparticles are difficult. Transfers of SnO2 nanoparticles can only be achieved when applying a second laser pulse to the already transferred material, which improves the adhesion resulting in a complete pixel. A new approach of decomposing the transfer material during LIFT transfer was developed. Donor films based on UV absorbing metal complex precursors namely, SnCl2(acac)2 were prepared and transferred using the LIFT technique. Transfer conditions were optimized for the different systems, which were deposited onto sensor-like microstructures. The conductivity of the transferred material at temperatures of about 400 ∘C are in a range usable for SnO2 gas sensors. First sensing tests were carried out and the transferred material proved to change conductivity when exposed to ethanol, acetone, and methane.

  19. Synthesis of Nanocrystalline SnO2 Modified TiO2:a Material for Carbon Monoxide Gas Sensor

    Directory of Open Access Journals (Sweden)

    A. B. BODADE

    2008-11-01

    Full Text Available Nanocrystalline SnO2 doped TiO2 having average crystallite size of 45-50 nm were synthesized by the sol-gel method and studied for gas sensing behavior to reducing gases like CO, liquefied petroleum gas (LPG, NH3 and H2. The material characterization was done by using X-ray diffraction (XRD, Fourier transform infrared spectroscopy (FT-IR and scanning electron microscope (SEM. The sensitivity measurements were carried out as a function of different operating temperature in SnO2 doped TiO2. The 15 wt.% SnO2 doped TiO2 based CO sensor shows better sensitivity at an operating temperature 240°C Incorporation of 0.5 wt% Pd improved the sensitivity, selectivity, response time and reduced the operating temperature from 240°C to 200°C for CO sensor.

  20. A facile one-pot self-assembly approach to incorporate SnOx nanoparticles in ordered mesoporous carbon with soft templating for fuel cells

    International Nuclear Information System (INIS)

    Huang, Yingqiang; Zhai, Zhicheng; Luo, Zhigang; Liu, Yingju; Liang, Zhurong; Fang, Yueping

    2014-01-01

    Unique SnO x  (x = 1,2)/ordered mesoporous carbon nanocomposites (denoted as SnO x /OMC) are firstly synthesized through a ‘one-pot’ synthesis together with the soft template self-assembly approach. The obtained SnO x /OMC nanocomposites with various SnO x contents exhibit uniform pore sizes between 3.9 and 4.2 nm, high specific surface areas between 497 and 595 m 2  g −1 , and high pore volumes between 0.39 and 0.48 cm 3  g −1 . With loading of Pt, Pt–SnO x /OMC with relatively low SnO x content exhibits superior electrocatalytic performance, long-term durability, and resistance to CO poisoning for methanol oxidation, as compared to Pt/OMC, PtRu/C and Pt–SnO x /C, which may be attributed not only to the synergetic effect of embedded SnO x , but also to the highly ordered mesostructure with high specific surface areas and large pore volumes affording plenty of surface area for support of Pt nanoparticles. This work supplies an efficient way to synthesize novel ordered mesoporous carbon self-supported metallic oxide as catalyst support and its further potential application to reduce the cost of catalysts in direct methanol fuel cells. (paper)

  1. Hybrid functional band gap calculation of SnO6 containing perovskites and their derived structures

    International Nuclear Information System (INIS)

    Lee, Hyewon; Cheong, S.W.; Kim, Bog G.

    2015-01-01

    We have studied the properties of SnO 6 octahedra-containing perovskites and their derived structures using ab initio calculations with different density functionals. In order to predict the correct band gap of the materials, we have used B3LYP hybrid density functional, and the results of B3LYP were compared with those obtained using the local density approximation and generalized gradient approximation data. The calculations have been conducted for the orthorhombic ground state of the SnO 6 containing perovskites. We also have expended the hybrid density functional calculation to the ASnO 3 /A'SnO 3 system with different cation orderings. We propose an empirical relationship between the tolerance factor and the band gap of SnO 6 containing oxide materials based on first principles calculation. - Graphical abstract: (a) Structure of ASnO 3 for orthorhombic ground state. The green ball is A (Ba, Sr, Ca) cation and the small (red) ball on edge is oxygen. SnO 6 octahedrons are plotted as polyhedron. (b) Band gap of ASnO 3 as a function of the tolerance factor for different density functionals. The experimental values of the band gap are marked as green pentagons. (c) ASnO 3 /A'SnO 3 superlattices with two types cation arrangement: [001] layered structure and [111] rocksalt structure, respectively. (d) B3LYP hybrid functional band gaps of ASnO 3 , [001] ordered superlattices, and [111] ordered superlattices of ASnO 3 /A'SnO 3 as a function of the effective tolerance factor. Note the empirical linear relationship between the band gap and effective tolerance factor. - Highlights: • We report the hybrid functional band gap calculation of ASnO 3 and ASnO 3 /A'SnO 3 . • The band gap of ASnO 3 using B3LYP functional reproduces the experimental value. • We propose the linear relationship between the tolerance factor and the band gap

  2. Controllable synthesis of SnO2 nanowires and nanobelts by Ga catalysts

    International Nuclear Information System (INIS)

    Xie Xing; Shao Zhibin; Yang Qianhui; Shen Xiaoshuang; Zhu Wei; Hong Xun; Wang Guanzhong

    2012-01-01

    We report the morphology control of one-dimensional (1D) SnO 2 nanostructures by Ga catalysts using thermal evaporation method. Gallium (Ga), either from decomposition of GaN powder or from Ga metal, is adopted as a catalyst for the growth of long SnO 2 nanowires and nanobelts. At similar experimental conditions, quantities of nanobelts are formed instead of nanowires when the temperature and reaction time are increased. Such approach enables us to synthesize various morphologies of SnO 2 nanobelts with different side facets. Novel nanobelts with [0 0 1] growth direction with high energy side facets are obtained for the first time, which is attributed to the large amount of oxygen vacancies introduced in the nanobelts by the Ga catalysts. - Graphical abstract: Morphology control of one-dimensional SnO 2 nanostructures are realized via a thermal evaporation method. Novel nanobelts along [0 0 1] direction having high energy side facets were fabricated for the first time. Highlights: ► Morphology control of one-dimensional SnO 2 nanostructures are realized by Ga catalysts using thermal evaporation method. ► Oxygen vacancies influenced the growth directions in order to neutralize thermodynamic instability. ► Novel nanobelts with [0 0 1] growth direction with high energy side facets are obtained for the first time.

  3. 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.

  4. Synthesis of Monodisperse Walnut-Like SnO2 Spheres and Their Photocatalytic Performances

    Directory of Open Access Journals (Sweden)

    Jing Wang

    2015-01-01

    Full Text Available Novel walnut-like SnO2 spheres have been synthesized using a one-step hydrothermal reaction with SnCl2·2H2O and KOH as raw materials. The morphology, microstructure, and optical properties of the products were characterized by X-ray powder diffraction (XRD, Raman spectrum, scanning electron microscopy (SEM, transmission electron microscopy (TEM, selected area electron diffraction (SAED, and ultraviolet-visible (UV-Vis absorption spectroscopy. The detailed studies revealed that these synthesized spheres are highly monodisperse and have a uniform size of approximately 250 nm. Photocatalytic activity of the prepared SnO2 spheres was evaluated by the degradation of methylene orange. The synthesized SnO2 spheres exhibited excellent photocatalytic degradation. In addition, a possible formation mechanism of the walnut-like nanostructures was proposed based on reaction time-dependent experiments.

  5. Different valence Sn doping - A simple way to detect oxygen concentration variation of ZnO quantum dots synthesized under ultrasonic irradiation.

    Science.gov (United States)

    Yang, Weimin; Zhang, Bing; Zhang, Qitu; Wang, Lixi; Song, Bo; Wu, Fan; Wong, C P

    2017-09-01

    An ultrasonic method is employed to synthesize the Sn doped Zn 0.95 Sn 0.05 O quantum dots with green light emission. Sn 2+ and Sn 4+ ions are used to create different optical defects inside Zn 0.95 Sn 0.05 O quantum dots and the changing trend of oxygen concentration under different ultrasonic irradiation power are investigated. The photoluminescence spectra are employed to characterize the optical defects of Zn 0.95 Sn 0.05 O quantum dots. The UV-vis spectra are used to study the band gap of Zn 0.95 Sn 0.05 O quantum dots, which is influenced by their sizes. The results indicate that ultrasonic power would influence the size of Zn 0.95 Sn 0.05 O quantum dots as well as the type and quantity of defects in ZnO quantum dots. Changing trends in size of Sn 2+ and Sn 4+ doped Zn 0.95 Sn 0.05 O quantum dots are quite similar with each other, while the changing trends in optical defects types and concentration of Sn 2+ and Sn 4+ doped Zn 0.95 Sn 0.05 O quantum dots are different. The difference of the optical defects concentration changing between Sn 2+ doped Zn 0.95 Sn 0.05 O quantum dots (V O defects) and Sn 4+ doped Zn 0.95 Sn 0.05 O quantum dots (O Zn and O i defects) shows that the formation process of ZnO under ultrasonic irradiation wiped oxygen out. Copyright © 2017 Elsevier B.V. All rights reserved.

  6. A feasibility study on SnO{sub 2}/NiFe{sub 2}O{sub 4} nanocomposites as anodes for Li ion batteries

    Energy Technology Data Exchange (ETDEWEB)

    Balaji, S., E-mail: sbalaji@tce.edu [Department of Chemistry, Thiagarajar College of Engineering, Madurai 625 015 (India); Vasuki, R. [Department of Physics, Thiagarajar College of Engineering, Madurai (India); Mutharasu, D. [School of Physics, Universiti Sains Malaysia, 11800 Penang (Malaysia)

    2013-03-25

    Highlights: ► The morphological analysis performed has shown the existence of nanocomposite. ► Sp. capacity after 50 cycles of pure NiFe{sub 2}O{sub 4}, 5 and 10 wt.% SnO{sub 2} are 450, 750 and 780 mA h/g. ► The results are higher than the theoretical capacity of graphite (374 mA h/g). ► The capacity retention is also found to increase with SnO{sub 2} addition in the NiFe{sub 2}O{sub 4}. ► Charge and discharge capacities of LiMn{sub 2}O{sub 4} vs. 10 wt.% SnO{sub 2}/NiFe{sub 2}O{sub 4} are 232 and 138 mA h/g. -- Abstract: The SnO{sub 2}/NiFe{sub 2}O{sub 4} nanocomposite samples with varying concentration of SnO{sub 2} such as 5 wt.% and 10 wt.% were synthesized via urea assisted combustion synthesis. The kinetics of the combustion reactions were studied using thermo gravimetry analysis and from which the compound formation temperature of all the samples were observed to be below 400 °C. From the morphological analysis the grain size of NiFe{sub 2}O{sub 4}, 5 wt.% SnO{sub 2}/NiFe{sub 2}O{sub 4} and 10 wt.% SnO{sub 2}/NiFe{sub 2}O{sub 4} samples were observed to be around 1.7, 2.3 and 3.5 μm. The chrono potentiometry analyses of the samples were performed against lithium metal electrode. The capacity retention was found to be higher for composite with 10 wt.% SnO{sub 2}. The discharge capacity of 10 wt.% SnO{sub 2} sample with respect to Li metal and LiMn{sub 2}O{sub 4} electrode was observed to be around 980 mA h/g and 138 mA h/g respectively.

  7. Graphene-supported SnO2 nanoparticles prepared by a solvothermal approach for an enhanced electrochemical performance in lithium-ion batteries.

    Science.gov (United States)

    Wang, Bei; Su, Dawei; Park, Jinsoo; Ahn, Hyojun; Wang, Guoxiu

    2012-04-13

    SnO2 nanoparticles were dispersed on graphene nanosheets through a solvothermal approach using ethylene glycol as the solvent. The uniform distribution of SnO2 nanoparticles on graphene nanosheets has been confirmed by scanning electron microscopy and transmission electron microscopy. The particle size of SnO2 was determined to be around 5 nm. The as-synthesized SnO2/graphene nanocomposite exhibited an enhanced electrochemical performance in lithium-ion batteries, compared with bare graphene nanosheets and bare SnO2 nanoparticles. The SnO2/graphene nanocomposite electrode delivered a reversible lithium storage capacity of 830 mAh g-1 and a stable cyclability up to 100 cycles. The excellent electrochemical properties of this graphene-supported nanocomposite could be attributed to the insertion of nanoparticles between graphene nanolayers and the optimized nanoparticles distribution on graphene nanosheets.

  8. Ternary SnO2@PANI/rGO nanohybrids as excellent anode materials for lithium-ion batteries

    International Nuclear Information System (INIS)

    Ding, Hongmei; Jiang, Hao; Zhu, Zhengju; Hu, Yanjie; Gu, Feng; Li, Chunzhong

    2015-01-01

    Highlights: • A three-dimensional ternary SnO 2 @PANI/rGO nanohybrids has been synthesized via dip-coating method. • PANI acts as the conductive matrix as well as a good binding agent of SnO 2 nanoparticles and graphene sheets, greatly improving the electrochemical performance. • The nanohybtrids, when applied as LIBs,exhibit a high reversible specific capacity of 772 mA h g −1 at 100 mA g −1 with excellent rate capability and high cycling stability. - Abstract: A three-dimensional (3D) nanostructure composed of ternary polyaniline/SnO 2 /graphene (SnO 2 @PANI/rGO) nanohybrids were successfully developed and prepared as anode materials for lithium ion batteries (LIBs) by a simple dip-coating of SnO 2 @polyaniline (SnO 2 @PANI) and graphene dispersion on Cu foam. In such smart nanostructures, polyaniline (PANI) acts as the conductive matrix as well as a good binding agent of SnO 2 nanoparticles and graphene sheets, greatly improving the rate performance to a great extent. The as-prepared ternary nanohybrids exhibit a high reversible specific capacity of 772 mA h g −1 at 100 mA g −1 with excellent rate capability (268 mA h g −1 at 1000 mA g −1 ), more significantly, after 100 cycles at 100 mA g −1 , our ternary nanohybrids still maintain a high specific capacity of 749 mA h g −1 , which is much better than SnO 2 /rGO(458 mA h g −1 at 100 mA g −1 ), SnO 2 @PANI (480 mA h g −1 at 100 mA g −1 ) and pure SnO 2 nanoparticles (300 mA h g −1 at 100 mA g −1 ). Such intriguing electrochemical performance is mainly attributed to the strong synergistic effects among SnO 2 , polyaniline and graphene. It is reckoned that the present 3D SnO 2 @PANI/rGO nanohybrids can serve as a promising anode material for LIBs

  9. A graphene–SnO{sub 2}–TiO{sub 2} ternary nanocomposite electrode as a high stability lithium-ion anode material

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Jicai [Key Laboratory of Automobile Materials, Ministry of Education, and College of Materials Science and Engineering, Jilin University, Changchun, 130025 (China); Roll Forging Research Institute, Jilin University, Changchun, 130025, Jilin (China); Wang, Juan; Zhou, Meixin; Li, Yi [Key Laboratory of Automobile Materials, Ministry of Education, and College of Materials Science and Engineering, Jilin University, Changchun, 130025 (China); Wang, Xiaofeng [State Key Laboratory of Inorganic Synthesis and Preparative Chemistry, College of Chemistry, Jilin University, Changchun, 130012 (China); Yu, Kaifeng, E-mail: yukf@jlu.edu.cn [Key Laboratory of Automobile Materials, Ministry of Education, and College of Materials Science and Engineering, Jilin University, Changchun, 130025 (China)

    2016-07-15

    In this work, a solvothermal method combined with a hydrothermal two-step method is developed to synthesize graphene–SnO{sub 2}–TiO{sub 2} ternary nanocomposite, in which the nanometer-sized TiO{sub 2} and SnO{sub 2} nanoparticles form in situ uniformly anchored on the surface of graphene sheets, as high stability and capacity lithium-ion anode materials. Compared to graphene–TiO{sub 2}, bulk TiO{sub 2} and grapheme–SnO{sub 2} composites, the as-prepared nanocomposite delivers a superior rate performance of 499.3 mAhg{sup −1} at 0.2 C and an outstanding stability cycling capability (1073.4 mAhg{sup −1} at 0.2 C after 50 cycles), due to the synergistic effects contributed from individual components, for example, high specific capacity of SnO{sub 2}, excellent conductivity of 3D graphene networks. - Graphical abstract: Graphene–SnO{sub 2}–TiO{sub 2} nanocomposite is synthesized by a hydrothermal two-step method. The composite exhibits higher reversible capacity and better cycle/rate performance due to the unique structure. - Highlights: • We have synthesized a graphene–SnO{sub 2}–TiO{sub 2} nanocomposite by a two-step method to improve the cycling performance. • Graphene–SnO{sub 2}–TiO{sub 2} nanocomposite is synthesized by a hydrothermal two-step method. • The composite exhibits higher reversible capacity and better cycle/rate performance due to the unique structure.

  10. 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.

  11. Reactivation and reuse of TiO2-SnS2 composite catalyst for solar-driven water treatment.

    Science.gov (United States)

    Kovacic, Marin; Kopcic, Nina; Kusic, Hrvoje; Stangar, Urska Lavrencic; Dionysiou, Dionysios D; Bozic, Ana Loncaric

    2018-01-01

    One of the most important features of photocatalytic materials intended to be used for water treatment is their long-term stability. The study is focused on the application of thermal and chemical treatments for the reactivation of TiO 2 -