Designing a Robust Ni-P/CeO2 Superhydrophobic Composite Coating for Synergistically Enhanced Corrosion Protection and Friction Reduction Performance.

Superhydrophobic surfaces have received widespread attention for their unique hydrophobicity in metal corrosion protection. However, the shortcomings of mechanical stability and long-term corrosion resistance limit their practical application. In this work, we designed and fabricated an anticorrosive and friction reducing Ni-P/CeO₂ superhydrophobic composite (SC) coating on a copper surface. The fabricated coating shows good superhydrophobicity with a water contact angle of up to 154°. The Ni-P support structure and CeO₂ nanoparticles form a multilayer micro/nanostructure by electrodeposition, ensuring excellent mechanical stability of the Ni-P/CeO₂ SC coating. Electrochemical tests indicate that the coating has excellent corrosion resistance due to the superhydrophobic air film, Ni-P barrier layer, and CeO₂ inhibition. Moreover, the friction coefficient of the coating is only 0.11 under dry friction conditions, showing excellent friction-reducing performance, which is attributed to the cooperation of the low adhesion coefficient of superhydrophobic surfaces, the ball-rolling effect of CeO₂ nanoparticles, and the self-healing effect of the Ni-P micro/nanostructure. This work provides a novel strategy for designing a robust superhydrophobic coating with mechanical stability, corrosion protection, and friction reduction abilities to inspire new applications of superhydrophobic surfaces.