Study on the Surface Wettability and UV Behaviors of ZnO Nanoarrays Coated by Cu₂O

ZnO nanoarrays coated by Cu₂O nanoparticles were fabricated on ITO substrates by electrochemical deposition method, and their structures and properties were characterized by scanning electron microscopy (SEM), X-diffraction pattern (XRD), and contact angle meter. The superhydrophobicity of ZnO nanomatarials is enhanced by depositing copper oxide nanoparticles with lower surface free energy. Many materials have higher adhesion to water because of capillary effect enclosing part of air between micropores and water, while the adhesion role in ZnO nanorod arrays is mainly from the van der Wallas's force. After depositing copper oxide on ZnO nanorod arrays, the fractal micro-nanostructures consisting of ZnO and Cu₂O decrease the contact area with water, thereby largely lowering the water adhesion on such a surface.