Gas-Sensing Simulation of Single-Walled Carbon Nanotubes Applied to Detect Gas Decomposition Products of SF_6

摘要

Chemical products detection and analysis has been demonstrated as a powerful diagnosis method for SF6 gas-insulated switchgear (GIS). In this paper, Materials Studio software was used to simulate a single-walled carbon nanotube (SWNT) detecting gas decomposition products of SF_6 in partial discharge (PD). The simulation results show SWNT was the most sensitive to SO_2 F_2 among the gas decomposition products of SF_6. SO_2F_2 molecules adsorbed on SWNT not only obviously changed electronic structures of SWNT, increasing the density of states (DOS) near Fermi level, but also greatly reduced the energy gap of SWNT, enhancing its electrical conductivity. However, SWNT is insensitive to HF, H_2S and CF_4 molecules because its properties were hardly changed when HF, H_2S and CF_4 molecules were adsorbed on SWNT. Although SO_2 and SOF_2molecules adsorbed on SWNT have changed the properties of SWNT to some extent, SO_2and SOF_2 can not be respectively detected by SWNT due to the cross-sensitivity between them.