Fabrication of Stable Superhydrophobic Cupric Hydroxide Surface with Hierarchical Structure on Copper Substrate

Cupric hydroxide films with a new hierarchical architecture consisting of beautiful nanotubes and nanoflowers were directly fabricated on copper substrate via a solution-immersion process at a constant temperature of 23?℃. Stable superhydrophobic Cu(OH)₂ surface was obtained after Cu(OH)₂ films were modified with hydrolyzed 1H, 1H, 2H, 2H-perfluorooctyltrichlorosilane (C₈H₄Cl₃F₁₃Si, FOTMS). The surface morphology and composition of the film were studied using scanning electron microscopy (SEM), X-ray diffraction (XRD), and X-ray photoelectron spectroscopy (XPS), respectively. Result shows that the surface of Cu(OH)₂ films directly grown on copper substrate was hydrophilic, whereas the modified Cu(OH)₂ films exhibited the superhydrophobicity with a water contact angle (CA) of about 160.8°, as well as a small sliding angle (SA) of about 1°. The special hierarchical structure, along with the slow surface energy leads to the high superhydrophobicity of the surface.