Synergistic effect of 2D/0D mixed graphitic carbon nitride/Fe2O3 on the excellent corrosion behavior of epoxy-based waterborne coatings

Polydopamine (PDA) functionalized graphitic carbon nitride nanosheets (PDCN) and α-Fe 2 O 3 nanoparticles (PDFe) were synthesized and characterized by FT-IR, XRD, TGA, XPS, and TEM. The complementary fillers of two-dimensional PDCN and zero-dimensional PDFe incorporated into waterborne epoxy (WEP) greatly improve the corrosion protect properties of composite coating, which was demonstrated through electrochemical impedance spectroscopy (EIS) and macroscopic surface morphology. Results showed that PDA modified g-C 3 N 4 and α-Fe 2 O 3 composite fillers (PDCN/Fe) have much superior synergistic effect on the improved barrier function of coatings than pure mixture of g-C 3 N 4 and α-Fe 2 O 3 (CN/Fe). This research indicates that the synergistic effect of nanofillers of different dimensions can be greatly stimulated by the good dispersibility in matrix, which has significant potential in improving corrosion protection properties of composite coatings.