Dissolved gases analysis in transformer oil using TM (Pd, Ir, Au) modified MoSSe monolayer: A DFT study

Abstract

This study applied density functional theory to investigate gas-sensitive devices based on transition metal-doped MoSSe (Pd-MoSSe, Ir-MoSSe, Au-MoSSe), exploring their adsorption and sensing performance towards three characteristic gases (CO, C2H2, C2H4) generated during the use or faults of transformer oil. The results indicate that Pd, Ir, and Au transition metal atoms preferentially anchor to the S surface of the pristine MoSSe monolayer. The doped monolayers exhibit significantly improved sensing characteristics in all aspects, suggesting chemical adsorption of the three characteristic gases. Through the analysis of band structures (BS), adsorption configurations, deformation charge densities (DCD), density of states (DOS), recovery time, and various adsorption parameters, the conclusion is drawn that while TM-MoSSe outperforms the pristine MoSSe monolayer in terms of adsorption and sensing performance, Pd-MoSSe and Au-MoSSe exhibit relatively good recovery times across a broader temperature range, whereas Ir-MoSSe is limited in this aspect. This study provides theoretical guidance for the potential application of transition metal-doped MoSSe monolayers as sensors for gases generated during the thermal runaway of transformer oil.