Theoretical study on the interaction between SF6 and TiO2 (001) surface: A DFT plus U study

Abstract

The research on SF 6 degradation and conversion is of great significance for environmental protection. Based on the density functional theory, the adsorption process of SF 6 on the TiO 2 (001) and TiO 2 (101) surfaces was investigated. The results indicate a strong interaction between SF 6 and the TiO 2 surface. Significant structural changes in the SF 6 , such as elongation of the S -F bonds, were observed after adsorption, rendering the SF 6 more prone to decomposition. According to Mulliken charge analysis, electron transfer occurs from the TiO 2 surface to the SF 6 , revealing SF 6 as an electron acceptor while TiO 2 acts as an electron donor. Analysis of the density of states confirms a pronounced electronic orbital overlap between the S/F atoms of SF 6 and the Ti/O atoms of TiO 2 , and the charge density distribution along the Z-axis further supports this charge transfer process. Additionally, experimental studies have demonstrated that TiO 2 photocatalysis can accelerate the degradation of SF 6 during DBD. This study demonstrates the catalytic potential of TiO 2 in the degradation of SF 6 insulating gas and provides theoretical support for the efficient and harmless treatment of SF 6 .