Density functional theory studies of Ti₃C₂T _x MXene nanosheets decorated with Au for sensing SF₆/N₂ nitrogen-containing decomposition gases

Abstract

SF6/N2 mixture is an alternative gas of SF6, which is already used in electrical equipment. When a malfunction occurs , SF6/N2 will decompose and further react with trace water and oxygen to produce nitrogen-containing gases such as NO, NO2, N2O and NF3. It is necessary to monitor these gases to ensure the safe operation of the equipment. This paper is based on density functional theory (DFT), the nanomaterial Ti3C2T x doped with Au atom was selected as sensing material. The result shows that Au/Ti3C2T x has larger adsorption energy when NO and NO2 adsorbed on the surface, the stable structures were conformed more easily with NO and NO2 compared with N2O and NF3. The density of states analysis and the frontier molecule orbital analysis reveal more change of the system before and after NO and NO2 adsorption, suggesting the material showed good sensitivity performance to NO and NO2. Thus, Au/Ti3C2T x is considered to have the potential for sensing NO and NO2.

First-Principles Investigation of Transition Metal (Co, Rh, and Ir)-Modified WS2 Monolayer Membranes: Adsorption and Detection of SF6 Decomposition Gases

“…SF 6 insulating gas is extensively employed in high-voltage and extra-high-voltage power system equipment for its outstanding insulation capabilities and arc-quenching properties. − Nonetheless, elevated temperatures and localized discharges within gas-insulated equipment may trigger the decomposition of SF 6 into H 2 S, SO 2 , SOF 2 , and SO 2 F 2 . − The oxygen atoms in SO 2 , SOF 2 , and SO 2 F 2 mainly come from oxygen and water. Previous studies have indicated that the proportion of oxygen atoms provided by oxygen and water varies under different fault conditions. − The increase of SF 6 decomposition gases significantly reduces the insulation performance of equipment, exacerbates insulation deterioration, and poses a serious threat to the safety of power systems.…”