2025/11/11 by Hamza Ahmad, Yuhuai Liu, Basheer Ahmed Kalwar +4
Materials Science · Medicine · Engineering · #High voltage insulation and dielectric phenomena #Plasma Applications and Diagnostics #Power Transformer Diagnostics and Insulation
paper · doi:10.1016/j.ssc.2025.116239
Sulfur hexafluoride (SF 6 ) circuit breakers always undergo partial discharges, leading to the breakdown of SF 6 into low-fluorine gases. The breakdown generates acids when low-fluorine gases mix with micro-water, resulting in damage to contacts and a reduction in arc-quenching efficacy. Owing to its importance, ongoing surveillance of degradation products is necessary. This work conducted density functional theory (DFT) calculations to assess the sensing efficacy of boron carbonitride (BC 2 N) monolayers for SF 6 breakdown products, including SOF 2 , SO 2 , SO 2 F 2 , H 2 S, and HF. The examination of adsorption behavior encompasses the evaluation of adsorption energy, charge density difference, and density of states measurements, while sensitivity is assessed by analyzing band structure, work function, and transmission data. The assessment of recovery attributes is conducted using estimations of desorption time. The investigation reveals that pure BC 2 N exhibits little interaction with gas molecules, but Cu- and Ag-decorated BC 2 N exhibit enhanced chemisorption, leading to increased adsorption energy levels of -0.88 to -1.44 eV for Cu and -0.85 to -1.35 eV for Ag. The examination of diffusion energy barriers indicates that Cu and Ag decorations maintain stability and inhibit cluster formation. The sensitivity of Cu/BC 2 N and Ag/BC 2 N to gas molecules is as follows: SO 2 F 2 : 87.5% and 60.1%; SOF 2 : 62.5% and 42.6%; SO 2 : 35.5% and 31%; H 2 S: 20.7% and 15.7%; HF: 14.6% and 8.2%. The desorption time calculation indicates that the most strongly coupled SO 2 F 2 molecule requires 112.8 hours to desorb at a temperature of 499 K; however, this duration is drastically reduced to 1.30 nanoseconds during UV light exposure. The target gas molecules may be swiftly adsorbed, detected, and desorbed by our suggested substrates, Cu/BC 2 N and Ag/BC 2 N, demonstrating their potential as extremely sensitive, reusable gas sensors.