In present work, pure and copper (Cu) doped SnO2 nanowires have been synthesized by thermal evaporation process at ambient pressure. Scanning electron microscopy (SEM) and transmission electron microscopy (TEM) indicated the growth of wire-like pure and Cu-doped SnO2 nanostructures with their length of about 50 microm and 80 microm whereas transverse dimension of about 50-80 nm and 20-50 nm, respectively. The HRTEM and SAED pattern reveals the growth of single crystalline Cu-doped SnO2 nanowire. The EDX confirms that Cu has been doped in the SnO2 nanowires and atomic fraction of Cu in nanowires is about 2.5 at% when concentration of CuO in starting source powder is 50 wt%. X-ray diffraction showed that Cu gets incorporated into the SnO2 lattice and also confirms their tetragonal rutile structure. For comparative study of gas sensing properties of pure and Cu-doped SnO2 nanowire, isolated single nanowire based sensors have been fabricated for detection of ethanol gas. The doping of Cu was found to enhance the ethanol sensitivity of SnO2 nanowire based sensors and the sensor response improves with increase in ethanol concentration. This sensing behaviour offers a suitable application of the Cu-doped SnO2 nanowire sensor for detection of ethanol gas.

In present work, one-dimensional nanostructure of Cu-doped Tin oxide (SnO 2 ) was synthesized by using thermal evaporation method in a tubular furnace under Nitrogen (N 2 ) ambience. The growth was carried out at atmospheric pressure. SEM and TEM images reveal the growth of wire-like nanostructures of Cu-doped SnO 2 on Si substrate. The XRD analysis confirms that the synthesized SnO 2 nanowires have tetragonal rutile structure with polycrystalline nature and X-ray diffraction pattern also showed that Cu gets incorporated into the SnO 2 lattice. EDX spectra confirm the doping of Cu into SnO 2 nanowires and atomic fraction of Cu in nanowires is ~ 0.5 at%. The Vapor Liquid Solid (VLS) growth mechanism for Cu-doped SnO 2 nanowires was also confirmed by EDX spectra. The optical properties of as grown Cu-doped SnO 2 nanowires were studied by using UV-vis spectra which concludes the band gap of about 3.7 eV. As synthesized single Cu-doped SnO 2 nanowire based gas sensor exhibit relatively good performance to ethanol gas. This sensing behaviour offers a suitable application of the Cu-doped SnO 2 nanowire sensor for detection of ethanol gas.

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This paper defines an idea of lowering the risk of accidents by installing

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In the present work, one-dimensional nanostructures of silicon oxide (SiO x) have been synthesized by thermal annealing method with and without chromium thin film on silicon substrate. The synthesis was carried out at different process temperatures ranging from 1000˚C to 1100˚C by using gold/chromium (Au/Cr) catalysts stack layer on the Si substrate in nitrogen (N 2) ambience. The as-synthesized SiO x nanostructures have tetragonal rutile structure and show polycrystalline nature. The SEM images reveal wire-like nanostructures on the substrate with and without chromium thin film. Under the catalytic reaction of the gold/chromium metal, the density of SiO x nanowires is enhanced, since the Cr layer serves as a diffusion barrier for the diffusion of the gold downwards into the Si substrate. The vapor-liquid solid (VLS) growth mechanism is found to be dominant in the growth of SiO x nanowires. Furthermore, X-Ray diffraction microscopy (XRD) and Photoluminescence spectroscopy (PL) analysis conclude the defect free growth of the SiO x nanowires on gold/chrome/silicon substrate.