Rapid response hydrogen sensor based on Pd@Pt/SnO2 hybrids at near-ambient temperature

H-2 sensors with rapid response at near-ambient temperature are ideal for application in explosion risk environments. Bimetallic catalysts are attractive in the field of superior properties gas sensing owing to their cooperative effects. This work synthesized Pd@Pt/SnO2 hybrids via a facile wet chemical method for H-2 sensing at near-ambient temperature. The sensing experimental results showed that Pd-1 @Pt/SnO2 possessed the highest response (785.15) to 1000 ppm H-2 at 50 ? and a short response/recovery time (1/9 s). Notably, the prepared Pd-2 @Pt/SnO2 presented a rapid response/recovery time (1/31 s) at 25 ?. Up to now, the Pd@Pt/SnO2 synthesized in this work displayed the fastest response at near-ambient temperature among those bimetal-decorated metal oxide semiconductor H-2 gas sensors. The excellent sensing capabilities of Pd@Pt/SnO2 to H-2 were due to the cooperative effects of Pd@Pt alloy caused the low activation energy, high oxygen species content, high resistance modulation and strong chemical sensitization. The Pd@Pt/SnO2 sensor has great potential advantage in rapid detection of H-2 at near-ambient temperature.