ZnO nanorods/Ag nanoparticles heterostructures with tunable Ag contents: A facile solution-phase synthesis and applications in photocatalysis

Needle-like ZnO nanorods (ZnO–NRs)/Ag nanoparticles (Ag–NPs) heterostructures with tunable silver contents have been successfully designed and constructed via a two-step hydrothermal approach on zinc foil. The as-fabricated heteroarchitectured composite was Ag–NPs with a size range about 30 to 50 nm in diameter assembled uniformly on the surface of needle-like ZnO–NRs, several micrometers long and about 480 nm wide near the half height of the nanorods. Through the variation of the reactant concentration such as silver nitrate, the silver content on the ZnO–NRs can be controllably tuned, which further greatly affected the photocatalytic performance of the decomposition of a representative dye pollutant of rhodamine B, and there is an optimum amount of secondary Ag–NPs. This facile method developed here also can be extended to construct other ZnO-based noble metal or semiconductor heterostructures on zinc substrates.