Realization of graphene on the surface of electroless Ni-P coating for short-term corrosion prevention

Abstract

Graphene was first fabricated on the surface of an electroless Ni-P coating/carbon steel (Ni-P-G) to improve its corrosion resistance. Meanwhile, an electroless Ni-P coating (Ni-P) was heated (Ni-P-H) under the same condition as Ni-P-G for comparison. The morphological results showed that a wavy multilayer graphene was formed on the surface of Ni-P-G. The layer number of the graphene film was 5-10 according to the analysis of Raman spectra and observation by a high-resolution transmission electron microscope. The ID/IG ratio calculated from the Raman spectrum revealed that the graphene growing at the grain of Ni-P-H had larger grain size than that growing at the grain boundary. The electrochemical results showed a higher Rp, a lower CPEdl, and a lower corrosion rate of Ni-P-G than Q235 steel, Ni-P, and Ni-P-H, indicating a higher corrosion resistance. In addition, the surface potential map achieved by a scanning Kelvin probe presented a more positive surface potential of Ni-P-G than Ni-P with the difference being around 375-750 mV, demonstrating a lower corrosion tendency of Ni-P-G.