A DFT calculation of fluoride-doped TiO2 nanotubes for detecting SF6 decomposition components

Abstract

Gas insulated switchgear (GIS) plays an important role in the transmission and distribution of electric energy. Detecting and analyzing the decomposed components of SF6 is one of the important methods to realize the on-line monitoring of GIS equipment. In this paper, considering the performance limits of intrinsic TiO2 nanotube gas sensor, the adsorption process of H2S, SO2, SOF2 and SO2F2 on fluoride-doped TiO2 crystal plane was simulated by the first-principle method. The adsorption mechanism of these SF6 decomposition components on fluorine-doped TiO2 crystal plane was analyzed from a micro perspective. Calculation results indicate that the order of adsorption effect of four SF6 decomposition components on fluoride-doped TiO2 crystal plane is H2S > SO2 > SOF2 > SO2F2. Compared with the adsorption results of intrinsic anatase TiO2 (101) perfect crystal plane, fluorine doping can obviously enhance the adsorption ability of TiO2 (101) crystal plane. Fluorine-doped TiO2 can effectively distinguish and detect the SF6 decomposition components based on theoretical analysis.