Annealing Effect on Nanocrystalline SnO2 Thin Films Prepared by Spray Pyrolysis Technique

In recent years, a transparent conducting oxide (TCO) SnO2 semiconductor have gained considerable attention due to their potential application in gas sensors. More number of studies on TCO oxide have focused on the semiconducting metal oxides in which an intensive argument is that the transparent semiconductors. The SnO2 thin films were deposited at 400 °C and then annealed at 500 °C and 600 °C and its structural, optical and electrical properties were characterized. The doping stoichiometric ratio was maintained as 4% and the resulting solution was sprayed on glass substrate which was kept at nozzle distance of 25 cm and the spray rate was 10 mL/min. The prepared pure SnO2 thin films have been characterized by different methods such as XRD, FESEM, UV-Vis NIR and EDAX analyses. It was found that the nanocrystalline SnO2 grains possesses structural features of the tetragonal rutile structure. Hence the prepared thin films are justified to be nanocrystalline and also the mean crystalline size decreased with respect to annealing temperature.

Structure and Optical Properties of Quantum Confined Pure and Cu Doped SnO2

Pure and copper doped tin oxide nanoparticles were synthesized by co-precipitation method and are characterized by XRD, SEM, EDAX, UV-Visible, photoluminescence, and FT-IR analysis techniques. Tetragonal rutile structure is confirmed from XRD and the crystallite size is found to be between 3.8nm and 4.8nm. The optical band gap is observed from UV-Vis spectrum and is found to be 3.99eV and 3.93eV for tin oxide and copper doped tin oxide respectively. The optical band gap of pure and Copper doped tin oxide were blue shifted due to quantum confinement. Photoluminescence spectrum shows UV, blue and green emission peaks.

Electrospun Ag-doped SnO2 hollow nanofibers with high antibacterial activity

With the continuous improvement in medical science in modern times, the spread of bacterial infection has become a matter of global concern. Therefore, the search for biological medical materials with antibacterial function has become a focus of intense research. In this work, pure SnO2 and Ag-doped SnO2 hollow nanofibers were fabricated by a combination of an electrospinning method and a calcination procedure, and the effects of the doped Ag on antibacterial activity were subsequently investigated. Through the process of high-temperature calcination, a high heating rate would lead to the formation of a hollow tubular structure in SnO2 fibers, and Ag2O would be reduced to Ag0 by a facile process with appropriate thermal treatment. Additionally, the existence of SnO2 as a tetragonal rutile structure was confirmed. On the basis of pure SnO2, doping with silver greatly improved the antibacterial activity of hollow nanofibers. The formation mechanism and the antibacterial mechanism of pure SnO2 and Ag-doped hollow nanofibers are also discussed. This study has broad application prospects for biological medicine.

Facile Synthesis of Donut-like TiO2-SnO2 Nanocomposite Microspheres by a Two-step Hydrothermal Reaction and Subsequent Spray Drying Process and Its Electrochemical Lithium Storage Properties

Donut-like TiO2-SnO2 nanocomposite microspheres were successfully synthesized via a facile two-step hydrothermal reaction and subsequent spray drying. The protonated titanate nanowires with H2Ti3O7 phase in the nanocomposite precursor transformed into not anatase TiO2 but TiO2(B) crystal structure even after calcination at 400 ?. And the substitutional solid solution (Sn, Ti)O2 with the same tetragonal rutile structure as SnO2 was formed. Moreover, the hierarchical donut-like structure in TiO2-SnO2 nanocomposite microspheres constructed by the second-step hydrothermal and spray drying treatment was maintained after calcination at 400 ?. The electrochemical test showed that the as-obtained TiO2-SnO2 nanocomposite microspheres reached an initial discharge capacity of 640 m Ah g-1 at a current density of 40 mA.g-1, which is much higher than the theoretical capacity of TiO2(B).

VLS Synthesis and Characterization of SnO2 Nanowires

ABSTRACTWe have synthesized core-shell 1D nanostructures by the Vapor-Liquid-Solid (VLS) mechanism. Gold (Au) was used as a catalyst and tin oxide (SnO) powder as a precursor; the growth temperature was of 600 °C. These structures were characterized by XRD, SEM, TEM, EDS, and PL. The nanowires have an average diameter of 20 nm and their lengths are of tens of micrometers; the core is tin dioxide (SnO2) with the tetragonal rutile structure and it has an average diameter of 12 nm; the shell is amorphous Sn of 8 nm average thickness. Photoluminescence measurements show a broad band in the 400-800 nm range. On the same growth process, SnO2 nanoparticles and a mixture of SnO2 rods and wires were also obtained, at 400 °C and 800 °C, respectively.

Synthesis and Gas Sensitivity of SnO2 Nanoparticles

Tin dioxide (SnO2) nanoparticles have been synthesized in bulk quantity by thermal evaporation of SnO powder. The x-ray powder diffraction (XRD) analysis indicates that the nanoparticles are the tetragonal rutile structure of SnO2. Scanning electron microscopy (SEM) analysis shows that the size of the synthesized SnO2 nanoparticles is relatively homogeneous with diameter of about 10 nm. Gas-sensing components have been manufactured with the SiO2 nanoparticles. Their performances indicate that it has high sensitivity and selectivity to LPG, and the max sensitivity appears at 280°C, compared with C2H5OH, H2, CO and CH4.

Fabrication of Antimony Doped Tin Oxide (ATO) Films For Heat Insulated Glass Coating

The aim of this study is to develop an inexpensive method for preparing transparent and heat insulating tin oxide film. Antimony-doped tin oxide (ATO) thin films have wide variety of technical applications, such as high transmission of visible light and heat insulated coatings. Films were formed by the dip-coating of this colloidal suspension. The structure and morphology of these films were analyzed using XRD and SEM analysis. The optical properties of the ATO thin films were investigated using a UV–VIS spectrophotometer. The heat insulating performance was evaluated using Halogen lamps to irradiate a film coated glass which cover on wooden box for two hours. The results of this study indicate that only the SnO phase (tetragonal rutile structure) appeared in X-ray diffraction, and the Sb dopant does not from a second phase. However, the crystallinity of the SnO structure is impaired by the presence of antimony. For the heat insulating performance the ATO coated glass achieves better heat insulation than that of bare glass.

Synthesis and Characterization of SnO2 Nanowires Materials Prepared from Tin Powder

Tin dioxide (SnO2) materials are prepared by using vapor transport techniques through a vapor-liquid-solid (VLS) mechanism from Tin (Sn) powder. The SnO2 materials are synthesized onto the silicon substrate at temperatures 850 0C. Crystalline structure of SnO2 nanowires was investigated by X-ray diffraction (XRD) spectroscopy. XRD patterns of SnO2 exhibited tetragonal rutile structure with lattice parameters of a = 4.73 oA and c = 3.18 oA. Surface morphology of SnO2 films was characterized by scanning electron microscope (SEM), that SEM micrographs indicate nanowires-like structure. The Raman spectra of single-crystalline rutile SnO2 nanowires were studied, three vibration modes were observed at 475, 635 and 775 cm-1 corresponded to the typical feature of the SnO2 nanowires. A room temperature photoluminescence (PL) spectrum of SnO2 nanowires were in visible emission range.

SnO2 Nanowires with Branched Structures Synthesized by Thermal Evaporation of Sn Powders

Branched SnO2 nanowires were prepared by heating Sn powders. SEM images indicated that the single branched nanowires had diameters in the range 50-300 nm. XRD and SAED analysis revealed that the SnO2 nanowires were crystalline with tetragonal rutile structure. PL spectrum showed visible light emission.

Synthesis and Properties of SnO2 One-Dimensional Nanomaterials on Pt-Coated Substrates

We have synthesized the belt-like structures of tin oxide (SnO2) by carrying out the thermal evaporation of solid Sn powders. We have analyzed the samples with scanning electron microscopy, X-ray diffraction, transmission electron microscopy and photoluminescence (PL). The obtained nanobelts were single crystalline with a tetragonal rutile structure. PL spectrum exhibited the visible light emission. We have discussed the possible growth mechanisms.