CuO-Modified PtSe₂ Monolayer as a Promising Sensing Candidate toward C₂H₂ and C₂H₄ in Oil-Immersed Transformers: A Density Functional Theory Study

This work using the density functional theory simulates the strong potential of the CuO-decorated PtSe2 (CuO-PtSe2) monolayer as a recycle use C2H2 and C2H4 sensor in order to realize the arc discharge monitoring based on the nano-sensing method. Results indicate that CuO decoration causes strong n-type doping for the PtSe2 monolayer with a binding force (Eb) of -2.49 eV, and the CuO-PtSe2 monolayer exhibits strong chemisorption and electron-accepting properties in the two gas systems, with the adsorption energy (Ead) and charge transfer (QT) obtained as -1.19 eV and 0.040 e for the C2H2 system and as -1.24 eV and 0.011 e for the C2H4 system, respectively. The density of states reveals the deformed electronic property of the CuO-PtSe2 monolayer in gas adsorptions, and its sensing mechanism based on the change of electrical conductivity and the work function are uncovered. This work sheds light on the metal-oxide-decorated transition-metal dichalcogenides for gas sensor applications and would provide the guidance to explore novel sensing materials in many other fields as well.