Conceptual Examination of Pt Atom-Adorned WTe2 for Improved Adsorption and Identification of CO and C2H4 in Dissolved Gas Analysis

The online monitoring of transformer insulation is crucial for ensuring power system stability and safety. Dissolved gas analysis (DGA), employing highly sensitive gas sensors to detect dissolved gas in transformer oil, offers a promising means to assess equipment insulation performance. Based on density functional theory (DFT), platinum modification of a WTe₂ monolayer was studied and the adsorption behavior of CO and C₂H₄ on the Pt-WTe₂ monolayer was simulated. The results showed that the Pt atom could be firmly anchored to the W atoms in the WTe₂ monolayer, with a binding energy of -3.12 eV. The Pt-WTe₂ monolayer showed a trend toward chemical adsorption to CO and C₂H₄ with adsorption energies of -2.46 and -1.88 eV, respectively, highlighting a stronger ability of Pt-WTe₂ to adsorb CO compared with C₂H₄. Analyses of the band structure (BS) and density of states (DOS) revealed altered electronic properties in the Pt-WTe₂ monolayer after gas adsorption. The bandgap decreased to 1.082 eV in the CO system and 1.084 eV in the C₂H₄ system, indicating a stronger interaction of Pt-WTe₂ with CO, corroborated by the analysis of DOS. Moreover, the observed change in work function (WF) was more significant in CO systems, suggesting the potential of Pt-WTe₂ as a WF-based gas sensor for CO detection. This study unveils the gas-sensing potential of the Pt-WTe₂ monolayer for transformer status evaluation, paving the way for the development of gas sensor preparation for DGA.