摘要
An in-situ CeO x /TiO 2 heterostructured MAO coating was constructed. • Ce incorporation promoted pore sealing and coating densification. • The optimized coating achieved corrosion current density of 4.29 × 10 -9 A/cm 2 . • Antibacterial rate exceeded 90% via Ce release and ROS generation. • Ce 3+ /Ce 4+ redox induced charge redistribution and bandgap narrowing. Under marine service environments, titanium is facing dual threats of corrosion and microbial contamination. In this study, a CeO x nanocluster-modified TiO 2 is constructed on pure titanium via Micro-arc Oxidation technology with in-situ cerium salt introduction to control plasma discharge characteristics. It is found that the coating porosity with optimal Ce concentration is just 2.29%, and the thickness increases to 22.25 μm. The electrochemical testing reveals that the coating’s corrosion current density drops to 4.29 × 10 -9 A/cm 2 , and the charge transfer resistance reaches 3.78 × 10 6 Ω∙cm 2 , which still maintains a stable capacitive response after 14 days. This result is attributed to the combined effects of structural densification and electronic regulation at heterogeneous interfaces. Meanwhile, the antibacterial rates of the coating against Pseudomonas aeruginosa and Staphylococcus aureus reach 91.25% and 82.56%. According to experimental characterization and calculation of Density Functional Theory, it is confirmed that the Ce 3+ /Ce 4+ redox pair not only drives redistribution of interface electrons, but also effectively reduces activation energy barrier of oxygen radicals, realizing efficient antibacterial activity through synergistic effect of the Ce x+ ion release and accelerated generation of Reactive Oxygen Species. Hence, this study provides a theoretical basis for designing rare-earth-modified multifunctional marine protective coatings. Download: Download high-res image (73KB) Download: Download full-size image
危险品化学品经营许可证（带存储）