Preparation of Au nanoparticle-decorated ZnO/NiO heterostructure via nonsolvent method for high-performance photocatalysis

In this paper, we present a novel physical (or nonsolvent) route to fabricate a kind of Au/ZnO/NiO heterostructure photocatalytic composite. That is, a Zn layer upon Ni foam substrate is prepared by pulse electrodeposition, then the ZnO nanoneedle/NiO heterostructural composite is obtained via thermal oxidation, and at last, the composite is modified with the dispersively deposited Au nanoparticles (Au NPs) by ion sputtering. The surface plasmon resonance effect of the Au NPs significantly enhances the light absorption. Meanwhile, the Au NPs form a Schottky barrier with ZnO nanoneedles and further inhibit the recombination of photogenerated electron–hole pairs. In addition, due to the nonsolvent conditions, the introduction of impurities is avoided, and thus it shows strong photocatalytic stability. The experimental results reveal that, the optimized Au/ZnO/NiO composite exhibits up to two times photocatalytic performance on RB degradation and higher stability than that of regular ZnO/NiO composite. The present experimental strategy can also be used for other noble metals, and it is expected to have important application prospects in the fields of environmental purification, solar cells, hydrogen generation, etc.