Theoretical study of SF6 decomposition on the MoS2 monolayer doped with Ag, Ni, Au, Pt: a first-principles study

Abstract

SF6 as a greenhouse gas, how to efficiently decompose it becomes a hotpot in the environmental field. Based on the first-principles calculations, this paper studied the interaction mechanism of SF6 gas molecules on transition metal (TM) doped MoS2 surface. The adsorption energy, energy barrier, charge transfer, density of states and electron density difference have been discussed. The results show that TM doping can enhance the interaction of MoS2 surface with SF6 molecules compared to undoped MoS2. Among the four (Au, Pt, Ag, Ni) doping conditions, the adsorption energies of SF6 molecules in the Au–MoS2 and Pt–MoS2 systems were 0.306 eV and 0.249 eV, the charge transfer process was weak, and the SF6 molecule did not change significantly. In the Ag–MoS2 and Ni–MoS2 systems, the adsorption energies reached 0.464 eV and 0.473 eV, and the DOS and differential charge analysis show that there were strong charge transfer process and electron orbital interaction between SF6 and MoS2. The decomposition energy barriers of SF6 on Ag–MoS2 and Ni–MoS2 surface were 0.696 eV and 0.432 eV, respectively. The S–F bonds were obviously elongated. The results show that Ag–MoS2 and Ni–MoS2 have catalytic potentials for the decomposition of SF6.