Fabrication of hydrophobic surfaces using copper electrodeposition and oxidation

The fabrication process of metallic hydrophobic surfaces was investigated using copper electrodeposition and oxidation. Hierarchical structures have well known advantages for producing super-hydrophobic surfaces. A micro-pillar array with a hierarchical structure of copper was fabricated through a sequential process of laser ablation followed by electrodeposition. Heat oxidation enhanced the hydrophobicity of both flat and micro-structured copper surfaces. Electrodeposition at higher current density gave a hierarchical structure with low surface energy, resulting from the presence of copper oxide. Fabricated surfaces with a depth of more than 100 micrometers display super-hydrophobicity. The effects of copper oxide and hierarchical structure were confirmed by an oxidation test of the fabricated structures, because the thickness of copper oxide was undetectable by XRD and XPS.