Corrosion protection properties of novel epoxy nanocomposite coatings containing silane functionalized graphene quantum dots

In this research, the effect of silane functionalized graphene quantum dots (f-GQDs) on the corrosion resistance of solvent-based epoxy coatings was investigated. The GQDs were prepared under hydrothermal method by using citric acid as precursor at 160 degrees C for 4 h. In order to increase the structural compatibility between GQDs and polymer matrix, the synthesized GQDs were chemically modified by (3-aminopropyl) triethoxysilane. The GQDs were characterized by X-ray diffraction, Fourier transform infrared spectroscopy, fluorescence emission, and transmission electron microscopy. Then, epoxy nanocomposite coatings containing f-GQDs were spray coated on mild steel substrate and the corrosion protection properties of epoxy/f-GQDs were studied via potentiodynamic polarization test and electrochemical impedance spectroscopy. The results showed that the corrosion protection performance of epoxy coatings had improved effectively with addition of low-cost and highly tunable f-GQDs due to their barrier performance in polymer coatings. (C) 2017 Elsevier B.V. All rights reserved.