The effect of sol-gel based silane film loaded with functionalized graphene oxide on the corrosion protection performance of epoxy coating on the steel substrate

Graphen oxide nanosheets modified with 3-aminopropyltriethoxysilane (APTES) were incorporated into the silane film based on the mixture of tetraethylorthosilicate (TEOS) and APTES. The functionalized GO (fGO) was characterized by Fourier transform infrared (FT-IR) spectroscopy and thermal gravimetric analysis (TGA). The steel substrate was treated by hybrid silane film containing 0.1 wt.% fGO and then the epoxy coating was applied on the surface treated substrates. The corrosion resistance of the steel substrates treated by silane film was evaluated before and after application of the epoxy coating by electrochemical impedance spectroscopy (EIS). Results revealed that the surface functionalization of GO by APTES was successfully done. It was observed from the EIS analysis that surface treatment of steel substrate by silane film containing fGO significantly enhanced its corrosion resistance. Also, the positive effect of silane film loaded with fGO on the corrosion protection performance of the epoxy coating was observed.