Adsorption performance of SF6 decomposition (SO2, SOF2, SO2F2) upon transition metal (Pt, Pd, Rh) modified GaSe monolayer

[Display omitted] •Transition metal modification (Pt, Pd, Rh) enhances GaSe conductivity, with Rh > Pt > Pd.•Adsorption of SO2, SOF2, and SO2F2 is improved, causing structural deformation in Pt-GaSe but maintaining stability in Pd-GaSe and Rh-GaSe. Chemical adsorption leads to more stable structures.•Conductivity analysis shows varying effects on Pt-GaSe, Pd-GaSe, and Rh-GaSe upon gas adsorption. Pt-GaSe holds promise for resistive SO2F2 sensors, Pd-GaSe for SO2 detection, and Rh-GaSe for multi-gas detection at specific temperatures. Detection and absorption of SF6 decomposition products in the gas-insulated switchgear (GIS), can greatly delay the aging of insulation media. Thus, the materials with more sensitive and better adsorption performance are aimed to find. In this study, Pt, Pd, and Rh modified GaSe are proposed as the gas sensing materials for detecting the characteristic decomposed gases (SO2, SOF2, SO2F2). The adsorption energy, density of states, energy band, electrical conductivity, recovery time are calculated to analyze the modification and gas adsorption processes. The applicability of the proposed material in three target gases is evaluated. The results show that GaSe doped with Pd, Pt, and Rh have better adsorption capacity for SO2, SOF2, and SO2F2. Moreover, the target gases can be quickly desorbed by heating after adsorption, ensuring the reusability of the GaSe material. Research content of this paper could provide reference to select suitable materials to detect SO2, SOF2, and SO2F2.