Adsorption of SF(6) Decomposition Products by the S Vacancy Structure and Edge Structure of SnS(2): A Density Functional Theory Study

[Image: see text] Detecting the composition and concentration of SF(6) decomposition products is an effective method to evaluate the state of gas-insulated switchgear. Based on density functional theory, in this work we investigated the adsorption properties of four typical SF(6) decomposition products (H(2)S, SO(2), SOF(2), SO(2)F(2)) on an SnS(2) S vacancy structure (SnS(2)-S(v)) and SnS(2) edge structure (SnS(2)-edge). By calculating the adsorption energy, charge transfer, and comparing the density of states (DOS) of each system before and after the adsorption of gas molecules, the physical and chemical interactions between SnS(2) with different structures and gas molecules were investigated. The results show that SnS(2)-S(v) has the largest adsorption energy for SO(2) and has obvious chemical interactions. The S vacancy can effectively capture an O atom in SO(2), causing SO(2) to firmly adsorb in the S vacancy. In addition, the adsorption of the four gases on the SnS(2)-edge is physical adsorption, in which the 50% S edge structure has the largest adsorption energy for H(2)S, reaching −0.52 eV, and there is also a large charge transfer between the 50% S edge structure and H(2)S. Although the adsorption energy of SnS(2)-edge to the four gases is smaller than SnS(2)-S(v), it is still greater than the pristine SnS(2). This paper explores the adsorption properties of SnS(2)-S(v) and SnS(2)-edge for SF(6) decomposition products, providing insights for the development of SnS(2)-based gas sensors.