Robust nickel-reduced graphene oxide-myristic acid superhydrophobic coating on carbon steel using electrochemical codeposition and its corrosion resistance

We report a facile approach to fabricate superhydrophobic (SHP) coating of nickel (Ni)–reduced graphene oxide (rGO)-myristic acid on carbon steel (CS) surface with superior corrosion resistance and self-cleaning ability, using electro-codeposition. The electro-deposition current density and electrolyte bath temperature are optimized to obtain the desired hierarchical surface textures with very high water contact angle (WCA). The microstructure, chemical compositions, surface roughness, and self-cleaning properties were examined using FESEM, XRD, XPS, EDX, AFM, water bouncing etc. A WCA of 174 ± 1.5°, with a sliding angle (SA) of ~1°, was obtained at 60 mA·cm−2 and 45 °C. The FESEM surface morphology showed a hierarchical pinecone structured Ni–rGO composite film. The good adhesion and mechanical stability of SHP coating is achieved by phosphating the surface prior to deposition. The SHP surface showed a two order reduction in the corrosion current density and ~3 orders higher impedance, as compared to uncoated surface. This study demonstrates a new approach for fabricating mechanically and chemically durable SHP coating on CS specimens. [Display omitted] •Ni-rGO based SHP surface is fabricated on carbon steel (CS).•SHP surface showed hierarchical pinecone of Ni-rGO deposits.•SHP CS showed 2 orders better corrosion resistance in 3.5 wt% NaCl.•Excellent cleaning efficacy and water repellency is achieved.•SHP surface showed good mechanical and chemical stability.