Adsorption and sensing of SF6 decomposition gas molecules by Ni-InN monolayer: A first-principles study

Abstract

SF₆ gas-insulated equipment is widely used in power systems; however, insulation defects and failures are inevitable over time, leading to the decomposition of SF₆ gas. Ni-modified InN exhibits excellent gas adsorption properties and can be applied in gas sensors. In this study, the doping process of Ni on the InN surface was simulated based on first-principles calculations, and an optimal adsorption model for the three decomposition gases of SF₆ (SO₂, SO₂F₂, SOF₂) was established. The adsorption characteristics of each system were analyzed by calculating parameters such as adsorption energy, charge transfer, adsorption distance, differential charge density, and density of states. Finally, the sensing performance was comprehensively evaluated to assess the potential application of Ni-InN as a sensing material. The results indicate that Ni-InN exhibits good adsorption effects on SO₂, SO₂F₂, and SOF₂, all of which demonstrate chemical adsorption with adsorption energies of −2.272 eV, −3.523 eV, and −1.829 eV, respectively. However, Ni-InN shows poor sensitivity to SO₂ and SO₂F₂, while it exhibits excellent sensitivity to SOF₂, suggesting that it could potentially serve as a sensitive material for SOF₂ detection. The findings of this study provide theoretical support for the application of InN-based sensors in the field of condition monitoring and fault diagnosis of SF₆ gas-insulated equipment.