Green modification of graphene oxide with phytic acid and its application in anticorrosive water-borne epoxy coatings

To develop a water-borne epoxy (WEP) nanocomposite coating containing graphene oxide (GO) nanomaterials with excellent anti-corrosion property, natural and nontoxic phytic acid (PA) molecules were used to functionalize GO for improving the compatibility between GO and WEP coating. The results of Fourier transform infrared spectroscopy, Raman spectroscopy, X-ray diffraction, ultraviolet-visible spectroscopy, X-ray photoelectron spectroscopy, and atomic force microscopy indicated successful decoration of PA molecules onto the surface of GO nanomaterials. Scanning electron microscopy analysis revealed that the dispersion performance of GO in WEP was significantly enhanced owing to PA modification. The results obtained from long-term electrochemical measurements and salt spray test confirmed that addition of well-dispersed PA-GO nanomaterials could remarkably enhance the barrier and corrosion protection capability of the WEP coatings.