Synthesis of SnO2 Nanowires their Structural and H2 Gas Sensing Properties

SnO2 nanowires were prepared on bare oxidized silicon, Au and SnO2 coated substrates by thermal evaporation of tin grains in argon atmosphere at 900°C. X-ray diffraction (XRD) and field-emission scanning electron microscopy (FE-SEM) were used to characterize the SnO2 nanowires. FE-SEM images indicated that the size of SnO2 nanowires depend on the type of substrate. Gas sensor was fabricated by dispersing SnO2 nanowires on an interdigitated Pt-electrode. H2 gas sensing properties of these sensors made of nanowires prepared on three different substrates were measured at various operating temperatures and concentrations respectively. SnO2 nanowires deposited on Au-coated substrates showed the highest sensitivity of 11.5 at 100°C upon exposure to H2 gas of 1000 ppm.