First-principles study of X(O, Se, Te)-doped monolayer MoS2 for Hg0 adsorption

Abstract

Hg0 has gradually become a serious environmental problem that need to be solved, due to its strong volatility and insolubility in water. In this study, the adsorption behavior of X(O, Se, Te)-doped monolayer MoS2 for was studied via DFT calculation to evaluate its potential for Hg0 removal. Oxygen group atoms X(O, Se, Te) doped MoS2 systems all have extremely high bonding energies, in which the strong interaction between the dopant atoms and the S vacancy of monolayer MoS2, resulting that dopant systems were greatly stable. Compared with pristine monolayer MoS2, X(O, Se, Te)-doped MoS2 has stronger adsorption performance and electrical conductivity in adsorbing Hg0, which is mainly attributed to the facilitation of electrons transfer between Hg0 and MoS2. The oxygen doping system exhibits best adsorption performance to Hg0, primarily due to the relatively stronger interaction between the dopant oxygen and Hg0. The results reveal that the O-doped monolayer MoS2 can effectively improve the adsorption efficiency of Hg0 increasing the application potential for mercury emissions control in coal-fired power plants.