Fabrication of superhydrophobic surface with hierarchical multi-scale structure on copper foil

A facile approach combining template and etching method together was applied to fabricate regular hierarchical multi-scale structure on a copper foil using the back surface of fresh bamboo leaf as the original template. After the hierarchical multi-scale structure was constructed on the copper foil surface, the water contact angle of the copper foil surface increased from 64° to 131.1°. Then the copper foil with hierarchical structure was modified by stearic acid, and the copper foil surface with hierarchical multi-scale structure showed superhydrophobic property with the water contact angle of 160.0°, and the sliding angle of the superhydrophobic copper foil surface was only 3°. The possible formation mechanism of the hierarchical multi-scale structure on the copper foil was discussed, and chemical resistance and mechanical resistance of the microstructured copper foil were studied. The reason of the wettability change of the copper foil surface was also analyzed. The provided method opens an amazing view for the transfer of hierarchical micro-, sub-micro-, and nano-structures of natural species onto metal surfaces.