SF6, as an outstanding insulation medium, is widely used in the high-voltage insulation devices, guaranteeing the safe operation of the power system. Nevertheless, the inevitable partial discharge in a long-running device causes the decomposition of SF6 and deteriorates its insulation performance. In this work, DFT calculations were performed to study the adsorbing and sensing properties of ZnO-modified C3N (ZnO-C3N) nanosheet towards SF6 decomposed products, in order to propose a novel nano-candidate for evaluating the operation status of SF6 insulation devises. We first investigated the structure of ZnO-C3N monolayer and then simulated its adsorption behaviour upon four typical SF6 decomposed species, namely H2S, SO2, SOF2, and SO2F2. It is found that the ZnO-C3N monolayer can exhibit desirable reactivity and sensitivity on SO2, SOF2, and SO2F2, leading to the intense deformation of gas molecules and large adsorption energies. These consequences allow the potential application of gas adsorbent based on ZnO-C3N monolayer for removing impurity gases from SF6 insulation equipment. According to the analysis, it is supposed that ZnO-C3N monolayer is qualified to be used in maintaining insulation strength and ensuring the safe operation of power system.
Keywords: C3N monolayer; Density functional theory; Metal oxide modification; SF6 decomposed species.