Facile fabrication of nickel-cobalt phosphate-based fluorine-free superhydrophobic film with anti-corrosion and self-cleaning properties on Al alloy

Water repellency of superhydrophobic protective film is of great interest to anti-corrosion of metallic materials due to its reduced contact area with water containing aggressive ions and self-cleaning effect. In this study, a facile electrochemical method was presented for preparing superhydrophobic film with excellent anti-corrosion and self-cleaning properties on Al alloy. The superhydrophobic film comprised nickel-cobalt phosphate (NiCoPO) with a hierarchical micro-nano structure and stearic acid (STA) with low surface energy, while the NiCoPO provides an appropriate roughness and STA offers an inert chemical state. As expected, the superhydrophobic film of NiCoPO/STA on Al alloy demonstrates a champion water contact angle of 163 degrees and corrosion protection efficiency of 97.38%. Moreover, the water flow impact-bounce and abrasion measurements on the NiCoPO/STA surface demonstrate that the superhydrophobic film possesses decent mechanical durability. This facile electrochemical deposition method paves a universal pathway to fabricate superhydrophobic protective film with remarkable anti-corrosion and self-cleaning performance on metallic substrates. [GRAPHICS] .