Gas sensing properties of buckled bismuthene predicted by first-principles calculation
First-principles calculations are used to study the structural, electronic, transport and optical properties of buckled bismuthene with the adsorption of various gas molecules such as CO, O2, H2O, NH3, SO2, NO and NO2. By considering the van der Waals interactions between the gas molecules and buckled bismuthene, we find that the buckled bismuthene shows superior gas sensing performance than other 2D materials such as graphene and MoS2. The adsorption of CO, O2, H2O and NH3 molecules is a physisorption, whereas SO2, NO and NO2 are chemisorbed on the buckled bismuthene with large charge transfer and strong adsorption energy. After adsorption, the charges are transferred from buckled bismuthene to the molecules and the quantum conductance is changed by the adsorbed molecules. Furthermore, the work function of buckled bismuthene is changed with the adsorption of different molecules. Our results show that the electronic, transport and optical properties of buckled bismuthene is sensitive to the adsorption of gas molecules, which suggests that the buckled bismuthene holds great potential for application in gas sensors.