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.