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

The presence of hydrogen sulfide (H2S) determines the air quality of both indoor and outdoor environments. To measure H2S concentration levels in the environment, a variety of sensors have been developed. Metal oxide (MOx) 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, sensing performance of MOx towards H2S gas is previously reported in number of studies. Nanotechnology advancements are expected to lead to the progress of highly sensitive, stable, and selective MOx-based H2S gas sensors in the future. This review article aims at enlightening the various aspects of H2S gas sensing technology in an unpretentious yet comprehensive manner.