Copper-doped hybrid Agx–Auy@ZnO nanoparticles and their enhanced photocatalytic activities

摘要： In this paper, we report on the simple polyol synthesis of copper-doped hybrid Agx–Auy@ZnO photocatalysts. The obtained samples have been characterized by X-ray diffraction, UV–Vis diffuse reflectance spectroscopy, transmission electron microscopy and an N2 adsorption study. The experiment results show that Ag, Au and Ag–Au alloy nanoparticles (NPs) successfully load onto the surface of the assembled Cu-doped ZnO. The photocatalytic performances of Cu-doped Agx–Auy@ZnO nanomaterials have been tested using diuron herbicide as a model contaminant under simulated solar light irradiation. The addition of Ag and/or Au nanoparticles to doped ZnO was strongly beneficial to the rate constant displaying a volcano-like pattern as a function of the Ag and Au content. A maximum pseudo-first-order rate constant of 18.55 × 10?3 min?1, 22.70 × 10?3 min?1 and 24.74 × 10?3 min?1 was achieved on Cu-doped Ag0.3@ZnO, Au0.5@ZnO and Ag0.5–Au0.3@ZnO respectively. The Cu-doped Ag0.5–Au0.3@ZnO bimetallic nanoparticles show the highest photocatalytic activity due to the synergistic effect by effective electron transfer.