Adsorption of NO 2 , SO 2 , H 2 S, and NH 3 on Os-Doped WSe 2 Monolayers: A First-Principles Study.

In this study, DFT calculations are used to analyze the adsorption of industrial waste gases (NO 2 , SO 2 , H 2 S, and NH 3 ) on WSe 2 monolayers. The adsorption energy, energy band, density of states, charge transfer, and recovery time of the adsorption structures between the target gas molecules and the Os-doped WSe 2 are studied. Compared with pure WSe 2 monolayer, Os surface bonding doping WSe 2 (Os-modified WSe 2 ) and Os doping with Se vacancy of WSe 2 (Os-embedded WSe 2 ) exhibit improved gas molecule adsorption ability. Among them, the adsorption energy of the Os-modified WSe 2 monolayer on NO 2 , SO 2 , H 2 S, and NH 3 is greater than that of the WSe 2 monolayer. At the same time, it is proved that the Os-embedded WSe 2 can be used as a gas sensor for H 2 S and NH 3 gas molecules at a high temperature.