Mechanism insights and experimental feasibility of using boron nitride nanocones for rapid adsorption and degradation of SF6 decomposition compounds

Abstract

Abstract Gas-insulated switchgear (GIS) employs sulfur hexafluoride (SF6) as an insulating medium to shield electrical gadget. However, SF6 can decompose under sure situations, generating dangerous sulfur-based totally compounds which include SO2, SOF2, and SO2F2. These byproducts pose enormous dangers to both protection and environmental integrity. Efficiently adsorbing and disposing of those compounds is critical for ensuring operational reliability and reducing environmental dangers. This study investigates the adsorption and degradation mechanisms of SF₆ decomposition compounds (SO₂, SOF₂, and SO₂F₂) on boron nitride nanocones (BNNCs) using density functional theory (DFT) and ab initio molecular dynamics (AIMD) simulations. Our comprehensive analysis covers five distinct systems, exploring individual and combined adsorption scenarios. The findings reveal that the apex of BNNCs plays a crucial role in the adsorption process, showing high efficiency in adsorbing SO₂ (adsorption energy − 1.22 eV) and facilitating the catalytic breakdown of SOF₂ (adsorption energy − 1.57 eV). The positively charged potential at the nanocone’s apex significantly influences the dissociation and subsequent adsorption of fluorine atoms, with an energy barrier for F dissociation at the apex (1.8 kcal/mol) much lower than at the sidewall (5.3 kcal/mol). In gas mixtures, SO₂ preferentially binds to the apex region of BNNCs, with a bond length of approximately 1.38 Å. BNNCs demonstrate superior adsorption capabilities for SO₂ and SOF₂ compared to other boron nitride nanostructures, with adsorption energies up to 89% higher. The electron transfer analysis reveals that BNNC complexes act as potent electron donors, particularly in the case of BNNC@3SO₂F₂. Additionally, BNNCs show significant potential as sensors for detecting SO₂F₂, with a rapid recovery time of 4.67 ps and a notable decrease in the Fermi level energy to -4.97 eV upon adsorption. The study also provides insights into the angular distribution and charge density difference profiles, offering a detailed understanding of the adsorption mechanisms. These findings have important implications for improving the safety and efficiency of gas-insulated switchgear (GIS) and contribute to the development of more effective environmental protection solutions in electrical power systems.

Keywords

• BN nanocones
• Adsorption
• Degradation
• Sulfur-based compounds
• DFT-AIMD