Polyphenol-reduced graphene oxide toward high-performance corrosion inhibitor

Graphene as a physical barrier in organic coating exhibits good anticorrosion property, whereas its agglomeration would greatly debase such performance. Here, functionalized graphene was prepared via a green/facile method with tea polyphenol as reductant and graphene oxide (GO) as precursor. The anticorrosion performance of polyphenol-reduced graphene oxide (T-rGO) in waterborne epoxy coating was evaluated according to the electrochemical impedance spectroscopy, polarization curve, water absorption and salt spray test. Results indicate that the T-rGO/epoxy coating has the largest impedance modulus and corrosion potential, and the corrosion current density is an order of magnitude lower than that of pure epoxy coating. The T-rGO/epoxy coating displays excellent corrosion protection under continuous high salt spray environment, with pure epoxy coating as a comparison. T-rGO greatly enhances the corrosion resistance of waterborne epoxy coating, which is attributed to its good dispersibility and intrinsic characteristics.