The adsorption properties of environmentally friendly insulation gas C₄F₇N on Zn (0 0 0 1) and ZnO (1 0 1¯ 0) surfaces: A first-principles study

Recently, C₄F₇N has been considered as one of the most promising candidates to replace SF₆ due to its excellent insulation performance and environmental-friendly property. Metal zinc is widely used as a coating material in gas-insulated electrical equipment. However, its compatibility with C₄F₇N has never been explored before. In this paper, the adsorption properties of C₄F₇N on Zn(0 0 0 1) and ZnO(1 0 1¯ 0) surfaces were theoretically studied by a first-principles calculation. Adsorption energy, total charge transfer, density of states, and electron density difference were calculated to evaluate the compatibility of C₄F₇N with Zn and ZnO. The results demonstrated that the interaction between C₄F₇N and ZnO(1 0 1¯ 0) is stronger than that of Zn(0 0 0 1). The dissociation pathway of C₄F₇N after adsorption on the ZnO(1 0 1¯ 0) surface was also determined, which shows that ZnO(1 0 1¯ 0) has a catalytic effect on the decomposition process of C₄F₇N. Compared with Al(1 1 1) and Cu(1 1 1), the dissociation of C₄F₇N on ZnO(1 0 1¯ 0) has a higher energy barrier, indicating that the reaction is more difficult to occur. As a result, Zn and ZnO have certain compatibility with C₄F₇N, which was also verified by experiments. Therefore, we infer that Zn shows potentials to be used as anti-corrosion coating in C₄F₇N gas-insulated electrical equipment.