The effect of palladium incorporation on methane sensitivity of antimony doped tin dioxide

Palladium is a widely used catalyst in SnO2 gas sensors. At the same time, such sensors often contain antimony as a dopant to get the desired conductivity range for their real life applications. It has been observed that an optimum amount of antimony doping in tin dioxide gives the maximum gas sensitivity. With the addition of palladium (upto 2 wt.%) the resistance of SnO2 sensors has been found to increase, although the gas sensitivity maximum is achieved at 0.5 wt.% Pd-0. For antimony doped SnO2 sensors, the resistance increase saturates at a low palladium concentration (0.5 wt.%). However, the gas sensitivity of antimony doped SnO2 sensors rises with palladium concentration without showing any saturation upto 2 wt.% of Pd incorporation. (C) 2003 Elsevier Science B.V. All rights reserved.