Herein, an ionic liquid–graphene oxide hybrid nanomaterial was prepared via a facile grafting reaction between an imidazole ionic liquid and graphene oxide. FTIR, Raman, and XPS spectra demonstrated that imidazole ionic liquids were successfully covalently attached to the surface of graphene oxide nanosheets. The resulting hybrid nanomaterial, with a thickess of ca. 3 nm, can be stably dispersed in water. Results obtained from electrochemical impedance spectroscopy revealed that ionic liquid–graphene oxide hybrids effectively improved the anticorrosion performance of epoxy-based waterborne coatings. Moreover, ionic liquids performed two functions: (a) they facilitated the dispersion of graphene in a polymer matrix and then utilized the impermeable barrier capability of graphene and (b) they endowed the graphene sheets with a corrosion inhibition effect. The scanning vibrating electrode technique combined with electrochemical tests proved that the enhanced protective performance of the as-prepared composite coatings was attributed to the synergistic effect of the impermeable property of graphene nanosheets and the inhibitory function of the imidazole-based ionic liquid.
© Royal Society of Chemistry 2018