Adsorption Properties of Pd₃-Modified Double-Vacancy Defect Graphene toward SF₆ Decomposition Products

In this study, we investigate Pd₃-cluster-modified 555-777 graphene (Pd₃-graphene) as a novel resistor-type gas sensor to detect SF₆ decomposition products based on density functional theory calculations. We obtained and minutely analyzed the relevant parameters of each most stable adsorption configuration to explore the microscopic mechanism during gas adsorption. Theoretical results reveal that Pd₃-graphene shows great adsorption capacity and sensitivity toward those decompositions. High adsorption energies and abundant charge transfer amounts could guarantee a stable adsorption structure of decomposition gases on Pd₃-graphene surface. The complex change of density of states verifies a strong chemical reaction between the gases and the surface. Moreover, the conductivity of Pd₃-graphene would improve due to the decrease of energy gap, and the sensitivity was calculated as SOF₂ > H₂S > SO₂ > SO₂ F₂. This work provides an effective method to evaluate the operation status of SF₆ gas-insulated equipment.