Computational evaluation of sensing properties of a novel 2D diboron dinitride for detecting toxic gas molecules

Abstract

2D materials have the potential for superior sensing performance due to their distinctive surface properties. In this study, the sensing properties of a novel 2D diboron dinitride (n-BN) material for detecting four toxic gas molecules (H2S, NH3, SO2, and NO2) with and without an external electric field are investigated by the first-principles calculation method. The results show that the NO2 molecule has excellent trapping characteristics and sensing properties on the n-BN monolayer due to its significant adsorption energy (−2.06eV) and significant changes in conductance. It has a medium affinity for H2S, NH3, and SO2 molecules and a feasible recovery time for NH3 and SO2 molecules at room temperature. Meanwhile, the adsorption energy of NH3 is approximately linearly increased with the magnitude of the external electric field along the adding direction, which is different from the parabolic form of the other three gas molecules. The recovery time of H2S can be adjusted more suitable by adjusting the external electric field at room temperature. Combining these sensing properties, the 2D n-BN monolayer is expected to be an excellent sensitive gas detection material for H2S, NH3, and SO2 gas molecules, and a scavenger for NO2 gas molecules.