Nanomaterials and Nanotechnology (Dec 2011)
Synthesis, Characterization and Ethanol Sensing Properties of Tin Oxide Nanostructures
Abstract
One‐dimensional nanostructures of Tin oxide (SnO2) have been synthesized by thermal evaporation method with and with out a catalyst on silicon substrate. The nanostructure growth was carried out by using a mixture of SnO2 and graphite powders at a temperature of 1050C in nitrogen (N2) ambience. The synthesized SnO2 nanostructures show polycrystalline nature with tetragonal rutile structure. SEM investigation reveals wire‐like and rod‐shaped nanostructures on silicon substrate, with and without the gold catalyst layer respectively. EDX and TEM observation concludes that the uniform SnO2 nanowires (diameter ~ 25 nm and length ~ 50 μm) grow with vapor‐liquid‐solid (VLS) mechanism whereas, the SnO2 nanorods with varying diameter grow with vapor‐solid (VS) mechanism. UV‐ Vis spectra estimates that the optical band gaps of the SnO2 nanowires and nanorods were 3.92 eV and 3.67 eV respectively. As synthesized single SnO2 nanowire based gas sensor exhibit relatively good performance to ethanol gas. This sensing behaviour offers a suitable application of the SnO2 nanowire sensor for detection of ethanol gas.
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