Growth of PCN-222 on a Graphene Oxide Surface with Sodium Zinc Molybdate Loading: Boosting Self-Healing and Corrosion Resistance of Epoxy Coatings

Self-healing protective coatings, key to anticorrosion and substrate longevity, are a hot topic in materials science. We synthesized a novel self-healing epoxy coating (GPN/EP) by spraying. It is a graphene oxide (GO)/metal–organic framework (PCN-222) epoxy composite with a sodium zinc molybdate (NZM) inhibitor and is applied to steel substrates. The covalent bond between PCN-222 and epoxy resin boosts GO dispersion and interfacial compatibility in the matrix, vital for coating performance. FTIR, SEM, XPS, XRD, and TGA characterized GPN's morphology, structure, and composition. EIS and potentiodynamic polarization tests showed GPN/EP greatly enhanced steel's corrosion resistance. The coating's self-healing ability ensures continuous protection. The study also explored its self-healing process and mechanisms, guiding advanced anticorrosion material development.