Enhancement of the corrosion protection performance and cathodic delamination resistance of epoxy coating through treatment of steel substrate by a novel nanometric sol-gel based silane composite film filled with functionalized graphene oxide nanosheets

•Graphene oxide significantly enhanced corrosion resistance of silane film.•GO/silane film significantly improved corrosion protection performance of epoxy coating.•Adhesion between the epoxy coating and steel substrate was improved by GO/silane film.•GO/silane film noticeably reduced cathodic delamination rate of epoxy coating.

This study focuses on developing a sol-gel based silane film filled with functionalized graphene oxide nanosheets (fGO) to enhance the epoxy coating resistance against corrosion and cathodic delamination over the steel substrate. fGO and silane composite with fGO were characterized by X-Ray photoelectron spectroscopy (XPS), X-Ray diffraction analysis and thermal gravimetric analysis. The effect of silane treatment on the epoxy coating performance was studied by electrochemical impedance spectroscopy (EIS), salt spray and cathodic delamination tests. Results reveal that incorporation of fGO nanosheets into the silane film significantly enhances the corrosion protection performance of the epoxy coating and reduced cathodic delamination.