Three birds with one stone: multi-functional interface strengthening to construct self-warning smart coatings with integrated corrosion and fouling resistance

Interface defects can significantly diminish the protective performance of a system. Specifically, coating aging is accelerated markedly by UV radiation, high temperature, high humidity, and microbial attack. To address these issues, this study develops a functional integrated intelligent coating with anti-corrosion and anti-fouling capabilities (SCC/ZPhP) via interfacial reinforcement and multi-component composite engineering. In this system, sericite (SC) acts as both a barrier and a loading platform, aiming to enhance the coating’s barrier performance while mitigating particle aggregation. Furthermore, constructing a Ce/Zn heterostructure (C/Z) reduces the composite’s band gap (Eg), which effectively promotes charge separation and improves photocatalytic and photocathodic protection properties. 1,10-Phenanthroline encapsulated in polyacrylic acid (PhP) exhibits pH-responsive behavior, enabling on-demand release of the active component. The resulting red coloration facilitates visual identification of corrosion areas and supports self-healing protective effects. Compared to epoxy coatings (EP), the SCC/ZPhP coating demonstrates better weathering and anti-aging performance, maintaining impedance modulus of 101⁰ Ω·cm2 and 1011 Ω·cm2 after the exposure period. Moreover, the incorporation of active factors endows the coating with excellent anti-fouling capabilities, achieving an antimicrobial rate of up to 98%. This effectively inhibits the adhesion and accumulation of marine organisms, thereby significantly reducing the risk of structural damage. Therefore, this study proposes a novel design strategy for developing multifunctional intelligent protective coatings with anti-corrosion and anti-fouling functionalities. Such coatings offer promising potential to extend the service life and enhance the structural stability of offshore engineering systems.