First principles study of NH3, H2S, Cl2, and C2H2 gases adsorption on defective GaSe monolayer

Toxic gases emission poses serious environmental concerns and health risks. The Van der Waals type of layered materials is an emergent class of materials with extraordinary physicochemical properties which are highly attractive for gas sensors. This study report on the potential applications of the interaction between toxic gases of NH3, H2S, Cl2, and C2H2 and the defective GaSe monolayer with Se vacancy, O-doped, and N-doped based on density functional theory. The defective GaSe monolayer enhances the adsorption energy and charge transfer value after four toxic molecules are adsorbed on it, particularly, the Cl2 molecule is adsorbed on the Se-vacancy site of the GaSe monolayer. The distance between four toxic molecules and the defective GaSe monolayer is significantly reduced after adsorption.