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

Hg-0 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 Hg-0 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 Hg-0, which is mainly attributed to the facilitation of electrons transfer between Hg-0 and MoS2. The oxygen doping system exhibits best adsorption performance to Hg-0, primarily due to the relatively stronger interaction between the dopant oxygen and Hg-0. The results reveal that the O-doped monolayer MoS2 can effectively improve the adsorption efficiency of Hg-0 increasing the application potential for mercury emissions control in coal-fired power plants.