X-SnSe (X=Zn and Mn):Transition metal atom modified Sn vacancy SnSe monolayer adsorption properties and electronic mechanisms towards SF2, HF, SOF2, SO2 and H2S

Ensuring the safe and stable functioning of modern power systems and high-voltage insulating devices requires the development of a dependable online intelligent diagnostic and detection system for trace characteristic gases (SF 6 decomposition gases) in energy and power equipment. We report on studies of adsorption and electronic properties of SnSe monolayers and substituting Sn-vacancy with Zn and Mn atoms considering five SF 6 decomposition gases. Utilizing the first principles, the Zn and Mn atoms substituted the SnSe vacancy and acted as electron donors during the doping process (Zn: -2.150 e , Mn: 0.371 e ). Additionally, the binding energy for Zn is very high (-3.150 e ). The successful doping method is confirmed by the high binding energy (Zn: -2.150 eV, Mn: -6.327 eV) and the exceptional chemical stability. The adsorption energy of SO 2 , HF, and H 2 S fall within the optimal range of 0.4 eV - 0.8 eV for detecting ideally. Therefore, Zn-SnSe and Mn-SnSe can serve as highly efficient gas-sensitive sensing materials or adsorbents for real-time diagnosis and monitoring of high-voltage insulating equipment. Future applications can extend to online operation and maintenance of smart grid GIS equipment, SF 6 gas recovery and purification treatment, and early fault warning for high-voltage electrical equipment. The LUMO and HOMO systems in the adsorption systems of Mn-SnSe and Zn-SnSe exhibit a similar tendency, which can be utilized for refining the adsorption of gases. The adsorption capacity and selectivity for various gases are calibrated to offer theoretical foundation for designing efficient and selective gas sensing materials or adsorbents.