Gas sensing mechanism of dissolved gases in transformer oil on Ag–MoS2 monolayer: A DFT study

Abstract

Abstract Based on the density functional theory (DFT), the adsorption capabilities and electronic properties of Ag–MoS2 monolayer were discussed to fully discover the gas sensing performance to transformer oil decomposed gases (H2, CO, CH4, C2H6, C2H4 and C2H2). Specifically, the adsorption structure, adsorption energy, Mulliken charge analysis, deformation charge density, density of state (DOS), frontier molecular orbital analysis and band structure were explored. The analysis results illustrate that the adsorption to CO, C2H4 and C2H2 is strong, which is superior to the adsorption of H2, CH4 and C2H6. The narrower band gaps and increased electrical conductivity in all adsorption structures indicate that Ag–MoS2 monolayer is promising for the detection of studied gases. Therefore, the present study proposes an effective gas-sensing material to estimate the working state and insulation level of power transformers.