Si 改性 MoS2对 g3 环保气体典型分解组分的吸附特性研究.

g3（green gas for gird） environmental protection gas（C4F7N/CO2 mixture）, as the most potential new environmentally friendly insulating substitute gas for SF6, has received extensive attention in recent years. Defects such as partial discharge and overheating are detected by analyzing the decomposed components in the g3 gas-insulated combined switchgear, which plays an important role in the evaluation and diagnosis of the operation status of power equipment. In this paper, the modification of Si atoms is proposed to improve the gas sensing and adsorption properties of MoS2. Based on the calculation method of density functional theory（DFT）, the intrinsic properties of MoS2 are explored through parameters such as adsorption energy, charge transfer, density of states and local density of states. The adsorption gas-sensing mechanisms of MoS2 and Si-MoS2 to the typical decomposition components of g3 gas—COF2, CF4, CF3CN. The analysis shows that Si atoms have a stable doping structure on the surface of MoS2. Compared with the intrinsic MoS2, the conductivity of MoS2 modified by Si atoms has been effectively enhanced; Si-MoS2 exhibits strong chemical adsorption to COF2 and CF4 gases, it is weak physical adsorption to CF3CN, the adsorption strength is CF4＞COF2＞CF3CN, and in the adsorption process Si-MoS2 always acts as an electron donor, transferring electrons to gas molecules; Si-modified MoS2 has selective adsorption to g3 gas decomposition components. It provides a theoretical basis for the development of MoS2 high-performance gas sensors for detecting CF4 and COF2 gases. The research results are also of great significance in reducing greenhouse gas emissions and improving the operational stability of GIS（Gas Insulated Switchgear). [ABSTRACT FROM AUTHOR]