Fabrication of superhydrophobic reduced-graphene oxide/nickel coating with mechanical durability, self-cleaning and anticorrosion performance

There is a great challenge to fabricate superhydrophobic coating with excellent mechanical durability and corrosion resistance. Inspired by the pinecone-shaped structure, a novel reduced-graphene oxide (rGO)/Ni composite coating with pinecone-like micro/nanostructures was fabricated successfully on a stainless steel substrate using a simple electrodeposition method combining Ni pre-deposition and an elevated current assistant approach. The results show that the coating is of self-cleaning and superhydrophicity with a water contact angle (CA) of 162.7°±0.8° and a sliding angle (SA) of 2.5°±1.0°. Importantly, the coating still maintains the excellent self-cleaning and superhydrophicity, water CA of 155.8°±1.2° and SA of 5.9°±1.2°, even after 100-cycle mechanical abrasion. Meanwhile, the coating also exhibits good anticorrosion performance in 3.5 wt% NaCl solution, with 99.98% inhibition efficiency. The simple fabrication method may provide a cost-effective way to prepare mechanically durable, anticorrosive, self-cleaning and superhydrophobic coatings on metal substrates.