Adsorption performance of Cu-MoTe2 on SF6 decomposition products: A first-principles study

Detection of SF6 decomposition components is one of the best ways to diagnose early latent insulation faults in gas-insulated equipment, which can effectively prevent sudden accidents. Metal-doped MoTe2 is widely used as a gas sensor material in the field of real-time monitoring of gas decomposition components due to its excellent adsorption properties. In this paper, the adsorption performance and sensing characteristics of Cu-MoTe2 adsorption of SF6 decomposition components including SO2, H2S and SOF2 are calculated and analyzed based on first-principle. The results show that: the adsorption energies of Cu-MoTe2 for SO2, H2S and SOF2 are-1.196 eV,-0.881 eV,-0.024 eV, indicating that the adsorption for SO2 and H2S are chemisorption. However, the adsorption of SOF2 is physisorption. The same result is obtained for the calculation of the DOS. The work function results indicate that the potential of Cu-MoTe2 for detecting SO2 and H2S as a field effect sensor. The adsorbent material has a high sensitivity of 273546.56 and 5820652.37 for H2S and SO2 gases, and good desorption time for H2S adsorption at room temperature. It can be seen that Cu-MoTe2 has the potential of the application of chemical sensor materials.