Sensing-performance improvement of 2D MoSH based gas sensors for detecting NO, NO2, and NH3 gas molecules

Nitrogen group oxide is one of the major pollutants in the air, and its accurate and rapid detection is essential for environmental protection and human health. Therefore, it is of great significance to develop high-performance new line sensor for Nitrogen group oxide. Here, we investigate the potential of monolayer 2D MoSH materials as candidates for NO gas sensing using a combination of density functional theory and non-equilibrium functions to construct nanodevices based on MoSH monolayer, and theoretically study the adsorption behavior of MoSH monolayer to NO, NO₂, and NH₃ gas molecules. The results indicate that MoSH monolayer exhibit metallicity, and nanodevices based on 2D MoSH monolayer exhibit anisotropic transport properties and significant negative differential resistance effects(NDR). More interestingly, gas sensors based on MoSH monolayers exhibit typical chemical adsorption of NO, NO₂, and NH₃ gas molecules, and the anisotropic transport properties still maintain, but significant differences of sensitivity appear for these three gas molecules. Specifically, the MoSH based gas sensor has the highest sensitivity to NO, reaching 93.1 % and 76.3 % along the armchair and zigzag directions, respectively. These results show that 2D MoSH monolayer is an excellent gas-sensing material with excellent application prospects for NO gas detection.