Adsorption of dissolved gas molecules in the transformer oil on metal (Ag, Rh, Sb)-doped PdSe2 momlayer: A first-principles study

• DFT simulation results demonstrate that Rh-doped PdSe 2 greatly enhanced the H 2 adsorption performance. • The first principles validate that Sb-doped PdSe 2 is sensitive to the detection of C 2 H 2 gas in transformer oil. • The theoretical support of metal-doped PdSe 2 as candidate is provided for the detection of dissolved gas in transformer oil. High-sensitivity gas sensors to monitor dissolved gases in transformer oil are of high value for preventing safety problems in oil-immersed transformers. This paper performs simulations based on density functional theory (DFT). The PdSe 2 for five dissolved gases (H 2 , C 2 H 2 , CH 4 , CO and CO 2 ) in transformer oil is being investigated based on the sensing performance of three different metal-modified PdSe 2 of Ag, Rh, and Sb. By studying the desorption properties of the gas, Rh-PdSe 2 has the best desorption for H 2 at room temperature. It can be used as a candidate material to detect H 2 at room temperature. The adsorption and desorption performance of PdSe 2 for H 2 is good at high temperatures, and it can be used as a candidate material for H 2 detection at high temperatures. The adsorption effect of different systems on C 2 H 2 is very obvious, and it can be used as the detection of C 2 H 2 dissolved gas in transformer oil. Rh-PdSe 2 is suitable as a sensing material for CH 4 , and Ag-PdSe 2 has great sensing potential for CO. This work will provide a theoretical basis as well as preliminary ideas for experimenters.