Sensing performance of room temperature operated MEMS gas sensor for ppb level detection of hydrogen sulfide: a review

Abstract The presence of hydrogen sulfide (H 2 S) determines the air quality of both indoor and outdoor environments. To measure H 2 S concentration levels in the environment, a variety of sensors have been developed. metal oxide (MO x ) based gas sensors are among the most interesting class of MEMS sensors, capable of producing highly sensitive, selective, and specific signals in a plethora of chemical and physical signals. Nonetheless, in the presence of moisture, they have poor selectivity and response. However, the sensing performance of MO x towards H 2 S gas is previously reported in a number of studies. Nanotechnology advancements are expected to lead to the progress of highly sensitive, stable, and selective MO x -based H 2 S gas sensors in the future. This review article aims at enlightening the various aspects of H 2 S gas sensing technology in an unpretentious yet comprehensive manner.