CuO-Modified PtSe(2) Monolayer as a Promising Sensing Candidate toward C(2)H(2) and C(2)H(4) in Oil-Immersed Transformers: A Density Functional Theory Study

[Image: see text] This work using the density functional theory simulates the strong potential of the CuO-decorated PtSe(2) (CuO–PtSe(2)) monolayer as a recycle use C(2)H(2) and C(2)H(4) 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 PtSe(2) monolayer with a binding force (E(b)) of −2.49 eV, and the CuO–PtSe(2) monolayer exhibits strong chemisorption and electron-accepting properties in the two gas systems, with the adsorption energy (E(ad)) and charge transfer (Q(T)) obtained as −1.19 eV and 0.040 e for the C(2)H(2) system and as −1.24 eV and 0.011 e for the C(2)H(4) system, respectively. The density of states reveals the deformed electronic property of the CuO–PtSe(2) 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.