Fabrication of bio‐mimetic low surface energy modified copper‐ aluminum based superhydrophobic coating enhancing anti‐corrosion efficiency of metal by electro‐assisted deposition

Corrosion is an electrochemical process that degrade material's malleability, ductility, and mechanical strength, leading to significant economic losses. Conventional coatings available in the market have limitations, including high thickness, low anti‐corrosion efficiency, and poor stability. Recently, superhydrophobic coatings have gained visibility due to their diverse applications, including corrosion resistance. In this study, copper‐aluminum superhydrophobic coating is electrodeposited onto a steel substrate under varying deposition voltages and times. The coating is further modified with stearic acid, achieving a contact angle of 152°. To analyze the coating's characteristics, x‐ray diffraction analysis, fourier transform infrared spectroscopy, microstructure and roughness analysis, and open‐circuit voltammetry are conducted. The results confirmed the crystalline nature, lattice parameters, and grain sizes of copper (19.32 nm) and aluminum (22.45 nm). Corrosion resistance measurements demonstrated significant improvements, with an anti‐corrosion efficiency of 98 %, polarization resistance of 82,300 Ω·cm 2 , and an exceptionally low corrosion rate of 3.4 · 10 − 1 3 mm/year. The enhanced corrosion resistance is attributed to the rough nano‐flower structure, which minimizes electrolyte contact and reduces the exposed surface area. Copper‐aluminum composite coating has been engineered and functionalized with stearic acid to achieve robust superhydrophobicity. This innovative approach combines hierarchical structuring with low‐surface‐energy modification, offering exceptional corrosion protection.