A universal method to fabricate Cu films with superhydrophobic and anti-corrosion properties

Multi-functional Cu films were fabricated by an improved electric brush-plating technique and subsequent immersion treatment in ethanol solution of stearic acid. The brush-plated Cu film exhibited unique lotus-like surface architectures, which endowed it with highly hydrophobicity, instead of metallic intrinsic hydrophilicity. After solution-immersion for certain time, the Cu films were gradually covered by a continuous net-like layer of copper stearate nano-sheets with low surface energy, which finally rendered them stable superhydrophobic and even self-cleaning. Electrochemical measurement revealed that anti-corrosion property of Cu is intimately linked with its surface wettability, and the superhydrophobicity indeed provides high corrosion resistance for Cu substrate in corrosion environment. This strategy can extend generally to other relevant metals.