Low-temperature hydrogen detection sensor based on CeO_2 -DOPED SnO_2

摘要

Cost-effective H_2 detection sensors based on pure and CeO_2 (0.5 at%, 1 at%, 1.5 at%, 2 at%, 3 at%, 4 at%)-doped SnO_2 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 CeO_2_doped SnO_2 sample were analyzed and related with the sensing properties. The results show that the H_2 sensing performance of pure SnO_2 gas sensor can be improved a lot by CeO_2 doping. In particular, gas sensors based on 2 at% CeO_2/SnO_2 exhibited the greatest performance: high responsiveness at 160 °C (23.7 for 50 ppm hydrogen), about 3 times higher than pure SnO_2 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 CeO_2 on SnO_2 gas sensor for H_2 detection is discussed.