Preparation of porous micro–nano-structure NiO/ZnO heterojunction and its photocatalytic property

This paper introduced a novel physical route which combined pulse electrodeposition with thermal oxidation to obtain a porous micro–nano-structure NiO/ZnO heterostructural composite. Because ZnO nanoneedle directly grew from the porous Ni foam or NiO surface, and was accompanied with a short-range atom interdiffusion at the interface between ZnO and NiO, a heterojunction was formed and exhibited a high interfacial adhesion strength and high density. The experimental results revealed this composite had excellent photocatalytic performance, 2.5 times higher than that of pure ZnO. The reason was that the NiO/ZnO heterojunction improved the separation rate of photogenerated electrons and holes, and therefore enhanced photocatalytic efficiency.