Adsorption of SF6 decomposition gases (H2S, SO2, SOF2 and SO2F2) on Sc-doped MoS2 surface: A DFT study

Abstract

By detecting the decomposition gases of sulfur hexafluoride (SF6), the type of internal fault of gas insulated switchgear (GIS) can be determined. In this paper, the scandium atom doped molybdenum sulfide material (Sc-MoS2) was proposed, and the adsorption behaviors of four typical SF6 decomposing gases (H2S, SO2, SOF2, SO2F2) on the surfaces of intrinsic MoS2 and Sc-MoS2 are studied based on density functional theory (DFT) method. The adsorption models were established to calculate the electronic properties and adsorption parameters of the adsorption systems. The results show that Sc-MoS2 has excellent adsorption properties for SO2, SOF2 and SO2F2, but weak adsorption for H2S. Moreover, the adsorption effect for target gases was obviously enhanced by the introduction of Sc atom as the active center of the system. The findings are beneficial to refine the gas sensing mechanism of MoS2 materials and lay a foundation for SF6 decomposition gases detection based on MoS2 sensors.