Facile photochemical reduction synthesis of bimetallic Au and Pd nanoparticles on ZnO nanorods for improved photocatalytic degradation of methylene blue

Abstract

Abstract Using a nanocomposite of ZnO with noble metal nanoparticles (NPs) is a promising way to suppress the rate of recombination between electrons and holes, as this limits the photocatalytic performance of ZnO. Bimetallic NPs offer new properties that are different from their constituent monometallic NPs and are easily deposited on the ZnO surface through various methods. In this work, bimetallic Au and Pd NPs nanoclusters were deposited on ZnO nanorods (NR) growing on a glass substrate by a facile photochemical reduction method using a solar simulator (100 mW cm−2) at room temperature. The highest photocatalytic performance under ultraviolet light was achieved using ZnO/Pd and ZnO/AuPd photocatalysts, due to the localised surface plasmon resonance (LSPR) effect of Pd NPs and its role in reducing the recombination center and adsorption of oxygen molecules. Under simulated solar light, the performance of ZnO/Au and ZnO/PdAu was equivalent to that of ZnO/Pd and ZnO/AuPd nanocomposites due to the addition of the LSPR effect of Au NPs that worked effectively in the visible light region.