Enhanced photocatalytic activity of a pine-branch-like ternary CuO/CuS/ZnO heterostructure under visible light irradiation

Abstract

Nanostructured semiconductor photocatalysts with high specific surface areas and unique structures are expected with high performance for the photo-degradation of organic pollutants. In this work, novel pine-branch-like ternary CuO/CuS/ZnO heterostructure catalysts have been designed and successfully synthesized on a Cu foam substrate. Effective electron–hole separation, improved visible light utilization and efficient light harvesting by novel pine-branch-like heterostructures have been realized. The photocatalytic rate constant of a pine-branch-like CuO/CuS/ZnO heterostructure is 0.0156 min⁻¹, which is 2 times that of CuO/CuS (0.0078 min⁻¹) and 4.6 times that of CuO nanowires (0.0034 min⁻¹) in the degradation of RhB solution. The enhanced catalytic ability of the CuO/CuS/ZnO heterostructure is attributed to the unique heterostructure, which effectively enhances the absorption of sunlight and reduces the charge-carrier recombination. The stability and high efficiency of the novel cost-effective, non-toxic and easily-recyclable catalytic system can be extended to the photocatalytic field and solar water splitting for hydrogen generation.