Study on the resistive switching-anticorrosion synergistic effect mechanism of CeO₂/ZnO heterojunction films in simulated seawater

ZnO/CeO₂ and CeO₂/ZnO composite films were prepared by combining electrodeposition with hydrothermal methods. The study focused on how the heterojunction interface affects the resistance behavior and corrosion resistance of the films. The surface morphology, composition, structure, semiconductor type, and oxygen vacancy concentration of the films were observed and analyzed. Furthermore, the surface adsorption energy, oxygen vacancy formation energy, heterojunction binding energy, and diffusion barrier energy were calculated using density functional theory (DFT). The corrosion resistance and resistance switching properties of the films were examined through electrochemical methods tests. The results show that the oxygen vacancy concentration in the CeO₂/ZnO film is lower than in the single-layer thin film (ZnO, CeO₂), and its corrosion resistance is higher than that of the single-layer film. Conversely, ZnO/CeO₂ film exhibits the opposite trend. After applying a polarization voltage, the formation energy and diffusion barrier of oxygen vacancies in the CeO₂/ZnO system decrease, and the applied voltage promotes the generation and migration of oxygen vacancies. The polarization treatment enables cyclic switching between high and low resistance states, which significantly extends the film's service life and is expected to expand the application of resistance switching technology in the field of corrosion protection.