Research on Os-Modified C3N Nanosheets for Sensing and Adsorbing Dissolved Gases in 10 kV Distribution Transformer Oil for Fault Diagnosis

Online monitoring technology for transformers is a crucial safeguard for power supply, and diagnosing dissolved gases in 10 kV distribution transformer oil is considered an effective criterion for transformer fault detection. Using density functional theory, this paper simulated the adsorption process of five dissolved gases in a 10 kV distribution transformer on Os-modified C3N nanosheets, and by calculating the band structure, differential charge density, density of states, and work function, the related sensing and adsorption mechanisms were revealed. The results indicate that Os modification significantly enhances the gas-sensing response of C3N nanosheets, particularly for capturing C2H2 and CO, which is primarily attributed to the d-orbital electrons of the doped metal. The adsorption capability of Os-modified C3N nanosheets of dissolved gases follows the order C2H2 > CO > H2 > CO2 > CH4, with the adsorption type being physico-chemical adsorption, and these findings provide a theoretical foundation for developing high-sensitivity gas sensors for detecting dissolved gases in a 10 kV distribution transformer.