TiO2-SnO2 mixed oxide semiconductors are proposed as candidates for hydrogen gas sensors. The sensor responses in terms of the electrical conductance and the sensitivity to hydrogen partial pressure and temperature are analyzed in order to optimize the sensor performance.
TiO2-SnO2 polycrystalline ceramics were prepared by precipitation from SnCl4 and impregnation of TiO2 powder. Thin films were produced by rf reactive sputtering from Ti-Sn metallic target in the Ar+15%O2 reactive gas mixture. The influence of the system composition on gas sensing performance was investigated. The electrical resistance was measured as a function of hydrogen and methane activity in air at different temperatures between 600 K and 1200 K.