Enhancement of Adsorption Performance of Gases in Oil on a Cr-Modified SnS Monolayer Based on the First Principles

Dissolved gas analysis (DGA) is the most commonly used transformer fault diagnosis technology at present. In this paper, according to the method of first principles of density function theory (DFT), the gas-sensitive mechanisms of four oil-soluble characteristic gases (H, CO, CH, CH) on intrinsic SnS and Cr-SnS were studied. The adsorption energy and electron transfer were calculated, and the density of states, energy bands, and recovery times were analyzed. It was concluded that H and CH were physisorbed on the Cr-SnS monolayer, while CO and CH were chemisorbed. It is believed that the Cr-SnS material can be used in gas sensing for CO and CH. Cr-SnS is expected to serve as a gas detector for the detection of CO with both a good response and reusability. Therefore, Cr-SnS has very promising applications in the evaluation of the operation of oil-immersed transformers. This study will provide some help and inspiration for the development of the Cr-SnS monolayer in gas-sensitive materials.