Fabrication of epoxy composite coating with superior anticorrosive properties using a pH-responsive system based on 2D Zn-MOF nanosheets

Herein, two-dimensional Zn(Bim)(OAc) nanosheets (ZNS) were prepared using ultrasonication and surfactant-assisted methods. Subsequently, it was used as nanocontainer loaded with benzotriazole (BTA) corrosion inhibitor to fabricate BTA@ZNS nanocomposites with pH-controlled release characteristics. The morphology analysis exhibits that BTA@ZNS has a distinct lamellar structure. UV spectrophotometer measurements indicated the release rate of BTA reached 94.38 % in 24 h at pH=1. Adding BTA@ZNS as fillers into epoxy resin (EP) coating can form BTA@ZNS/EP composite coating with active anti-corrosion properties. Electrochemical impedance spectroscopy (EIS) demonstrates that BTA@ZNS/EP coating has superior corrosion resistance than other EP-based coatings. The enhanced anti-corrosion performance is ascribed to the barrier effect and acid-responsive controlled release of BTA@ZNS.