Low-temperature hydrogen detection sensor based on CeO2 -DOPED SnO2

Abstract

Cost-effective H2 detection sensors based on pure and CeO2 (0.5 at%, 1 at%, 1.5 at%, 2 at%, 3 at%, 4 at%)-doped SnO2 semiconductor oxides with both high moisture resistance and low operation temperature were prepared by a simple method. The crystal phase, morphology, and chemical composition of the obtained CeO2-doped SnO2 sample were analyzed and related with the sensing properties. The results show that the H2 sensing performance of pure SnO2 gas sensor can be improved a lot by CeO2 doping. In particular, gas sensors based on 2 at% CeO2/SnO2 exhibited the greatest performance: high responsiveness at 160 °C (23.7 for 50 ppm hydrogen), about 3 times higher than pure SnO2 sensor (6.9); short response and recovery time (2 and 9 s); good repeatability and long-term stability without any change after 30 days (23.7 for 50 ppm hydrogen), good selectivity, and moisture resistance. Finally, the function of CeO2 on SnO2 gas sensor for H2 detection is discussed.