Room Temperature Hydrogen Sensor Based on SnO2 : La2 O 3

A semiconductor gas sensor using tin dioxide along with palladium and lanthanum oxide was found to exhibit high sensitivity and selectivity to hydrogen in air compared to liquefied petroleum gas, carbon monoxide, methane, hydrogen sulfide, and ammonia at room temperature. The choice of La 2 O 3 and the noble metal additive and their exact loading were very critical for the detection of hydrogen. 0.5 wt % Pd and 2 wt % La 2 O 3 in tin dioxide was the optimized composition for maximum sensitivity to hydrogen at room temperature.