2-Mercaptobenzimidazole-inbuilt metal-organic-frameworks modified graphene oxide towards intelligent and excellent anti-corrosion coating

2-Mercaptobenzimidazole (M) was successfully inbuilt in zeolitic imidazolate framework-8 (ZIF-8) on GO nanosheets and then imbedded into epoxy coating to prepare composite coating with pH-responsive and self-healing performances. Results showed that M-ZIF-8/GO possessed remarkable pH-triggered activity. The excellent self-healing behavior of M-ZIF-8/GO/EP coating was demonstrated by local electrochemical impedance spectroscopy, which was attributed to the release of corrosion inhibitors that could form a compact protective film on the metal. The anti-corrosion performance of matrix coating was also enhanced effectively because M-ZIF-8/GO could react with epoxy resin which greatly increased the compatibility of M-ZIF-8/GO and the crosslinking density of epoxy coating.