Corrosion Resistance of Nickel/Chromium Graphene Oxide Coatings on Copper Substrate Surface and the Corrosion Resistance Mechanism of Graphene Oxide

Graphene oxide (GO) is characterized by hydrophilic edges and a more hydrophobic planar/basic skeleton, which makes it has potential applications in the field of corrosion. But its hydrophobicity hinders its co-deposition behavior in the electrolyte. To improve the corrosion resistance of copper-based substrate, this article designs and successfully prepares a nickel/chromium graphene oxide (NiCr-GO) composite coating. The paper studied the influence and mechanism of GO addition on the microstructure and corrosion resistance of the coating. The results indicate that a crack network and nodular structure have formed on the surface of the coating. The coatings with different GO contents are composed of nickel, chromium single-phase, and Cr2Ni3 inter-metallic compounds, and the grain size does not significantly change. With the increase in GO, the corrosion resistance of the composite coating is enhanced, and the optimal GO addition amount is 0.750 g/L. GO chips may form physical barriers in the crystal structure defects of the coating, or passive films on the material surface. This dual mechanism is the fundamental reason for improving the corrosion resistance of NiCr-GO.