The Effect Of Au Nanoclusters In Tin OxIDe Film Gas Sensors

The effect of Au nanoparticles in SnO2 was investigated for gas sensor applications. The films were prepared by the sol—gel method. HAuCl4 was added to a tin alkoxIDe solution, the mixture was hydrolyzed and spin coated on glass substrates. The samples were then thermally treated to remove the organics. The films were characterized by thermogravimetric analysis, scanning electron microscopy, and X-ray diffraction. Additionally, the optical absorbance and the reflectivity were measured. The films were tested against hydrogen. The change of the electrical conductivity was used to detect the gas. The response of SnO2 and SnO2—Au to H2 was investigated at different temperatures and concentrations. With the addition of Au nanoparticles the detection limit decreased, the working temperature was reduced (from 180°C to 140°C), and there was a ten times increase of the signal.