摘要
Cerium-based oxides have been widely reported as nanofillers to enhance the corrosion resistance and UV-aging stability of epoxy coatings. However, their protective performance primarily originates from defect states associated with Ce 3+ and oxygen vacancies in the lattice, which are typically present in limited quantities. In this study, zirconium-doped cerium oxide (CeZrO x ) nanoparticles were anchored onto hydroxylated boron nitride nanosheets (BNNSs) via a hydrothermal method. Zr doping significantly increases the concentration of defect states, thereby improving the UV absorption capacity and antioxidant activity of the nanofillers. The heterostructured BNNSs not only reduce the agglomeration of CeZrO x nanoparticles but also provide an effective passive barrier against corrosion. Electrochemical analyses revealed that cerium-based oxides increased the corrosion potential and influenced the anodic corrosion process, while Zr doping further promoted the formation of a dense protective Fe 3 O 4 passive film at the metal/coating interface. When incorporated into a waterborne epoxy matrix, CeZrO x @BNNS-EP exhibited markedly improved anticorrosion and anti-UV performance compared with coatings containing undoped CeO 2 @BNNS. After 24 h of UV aging, CeZrO x @BNNS-EP maintained an impedance modulus of 1.99 × 10 9 Ω/cm 2 after 12 d ays of immersion in 3.5% NaCl solution, which was eight times higher than that of the undoped counterpart. These enhancements are attributed to the increased antioxidant capacity and free-radical scavenging activity imparted by Zr doping, which facilitate anodic passivation during corrosion and mitigate UV-induced degradation. Overall, this work provides both mechanistic insight and practical guidance for the rational design of cerium oxide–based nanofillers for corrosion- and UV-resistant coatings.
危险品化学品经营许可证（带存储）