A highly sensitive MoS2 nanosheet gas sensor prepared by mechanically exfoliating for room temperature H2S detection

Abstract

Abstract Hydrogen sulfide (H2S) is a hazardous gas that is highly hazardous to human health, even at extremely low concentrations. Due to surface defects easily caused by hydrothermal or stepwise self-assembly methods, the response of the molybdenum disulfide (MoS2) gas sensor usually does not exceed 60%. In this article, mechanical exfoliation and full dry transfer techniques were used to reduce the surface defects of MoS2 nanosheets, improving the response of gas sensors to H2S at room temperature. The response to H2S was about 80% at a concentration of 15 ppm and about 12% at a concentration as low as 500 ppb. In addition, for 10 ppm H2S, applying a negative gate voltage, the response can be increased by approximately 10% to enhance the gas response. This study demonstrates the enormous potential of the gas sensor based on mechanical exfoliated MoS2 nanosheets for detecting low concentrations of H2S, providing new insight into the materials preparation of highly sensitive gas sensors.