Adsorption properties of Ag2O–MoSe2 towards SF6 decomposed products

Abstract In this study, the adsorption and gas-sensing properties of Ag2O–MoSe2 to SF6 characteristic decomposition products (H2S, SO2, SOF2 and SO2F2), have been study based on the first-principle calculations. The optimal structures, adsorption energy, band structure, density of states, differential charge density, and molecular orbital theory were used to analyze the adsorption mechanism. Results show that the adsorption capacity of Ag2O–MoSe2 to SF6 characteristic decomposition products is in following order: H2S > SO2>SO2F2>SOF2. All of the gas molecule adsorptions are exothermic, and occur spontaneously. State density analysis shows that H2S and SO2 adsorption belongs to chemical adsorption, while SOF2 and SO2F2 interact by physical adsorption. The recovery time shows that H2S is difficult to desorption after adsorption. While the desorption time of SO2 is much shorter than H2S, which improve the detection efficiency. In addition, the dissociation time of SOF2 and SO2F2 is very short. In conclusion, Ag2O–MoSe2 can be a potential gas sensing material for these four SF6 characteristic decomposition products detection.