Influence of Pd Clusters Doping on Gas Sensing Properties of TiO₂(101) Nanotubes to SF₆ Decomposition Products

Abstract

Detection and analysis of sulfur hexafluoride (SF6) decomposition components is one of the most used methods to realize online monitoring of gas insulated switchgear (GIS) faults. In this paper, Pd3doped anatase TiO2(101) surface was constructed, and studied about its geometric and electronic properties to characteristic SF6 decomposition products: SOF2 and SO2F2 based on DFT calculations. Comparing with intrinsic TiO2(101), the conductivity of Pd3-TiO2(101) surface decreases dramatically. Studies on adsorption energy, charge transfer, and adsorption distance show that Pd3-TiO2(101) shows strong chemisorption to SOF2 and SO2F2 molecules. Based on density of states and molecular orbital theory analysis, it is found that the adsorption of SOF2 and SO2F2 can dramatically change the conductivity in different degrees. As a result, the Pd3-TiO2(101) surface exhibits high gas sensitivity and selectivity to SOF2 and SO2F2 molecules. Our calculations would be meaningful for the development of new sensing materials for SF6 decomposition components detection.