Adsorption of dissolved gases on the TM (Pt, Pd) doped XP(X=In, Ga): A DFT study

Using 2D materials to detect dissolved gases in transformer oil can effectively evaluate the operating status of power systems. In this study, the Pt and Pd atoms are used to modify InP and GaP monolayers for detecting the target gases (C2H2, C2H4, CH4). The band gaps of modified structures are reduced and became more compact compared to the original substrates. The adsorption characteristics of the target gases on the modified substrates are systematically analyzed through adsorption parameters, DCD and DOS. The adsorption effect of the modified InP monolayers on the target gases is ranked as: C2H2>C2H4>CH4. The adsorption capacity of the modified GaP monolayers to the target gases is: C2H4>C2H2>CH4, however the adsorption capacity of the Pd-GaP/gases system is consistent with that of the modified InP monolayers. The sensitivity and recovery time of every gas adsorption systems are further analyzed. In addition, this study provides a theoretical direction for exploring the application prospects of InP and GaP monolayers in the evaluation of operating conditions of oil-immersed transformers. [Display omitted] •Transition metals Pt and Pd are selected to modify the InP and GaP monolayers for detecting the target gases (C2H2, C2H4, CH4). It is found that metal modification will change the conductivity of the monolayers.•Two modification methods have been developed for InP and GaP monolayers: One way is to use Pt and Pd atoms to modify the surface of a monolayer, and the other is to use Pt and Pd atoms to embed into a monolayer with P vacancy.•The application prospects of TM-XP(X=In, Ga) in gas sensors are analyzed from many aspects.