Superhydrophobic surface from Cu–Zn alloy by one step O2 concentration dependent etching

The article reports on a very simple method to fabricate superhydrophobic surfaces with Cu–Zn alloy via changing the local oxygen concentration and formation of oxygen difference cell, which can be readily realized by covering or contacting the Cu–Zn alloy surface with a glass slide. This superhydrophobic film comes from the formation of a flower-like hierarchical structure due to the accelerated alloy etching. In contrast, the white film grown in the un-covered area showed a much lower hydrophobicity due to its different morphology. These superhydrophobic surfaces or superhydrophobic–hydrophobic surfaces are expected to find applications in making self-cleaning alloy surface, in metal anticorrosion, and in biomineralization, etc.

Graphical abstractOne step chemical etching of Cu–Zn alloy results in different regions with contrast wettability from hydrophobicity to superhydrophobicity, which arises from different morphologies.Figure optionsDownload full-size imageDownload as PowerPoint slide