Photoreduction of palladium nanoparticles on ZnO nanorods for enhancing photocatalytic decolorization of methylene blue

Abstract

The high recombination rate of zinc oxide (ZnO) limits its photocatalytic activity and performance. Depositing noble metal nanoparticles (NPs) onto ZnO nanorods (NRs) is a promising approach that could facilitate interfacial charge-transfer processes, thereby increasing its photocatalytic activity. Generally, silver and gold NPs are used in conventional powdered structure, but in this work, due to the unique chemical and optical properties, palladium (Pd) NPs were utilized. Pd NPs were successfully deposited onto the surface of ZnO NRs by photoreduction process using a UV (365 nm) and a simulated solar light (Xe lamp). Irradiation by a Xe lamp produced a high number of Pd NPs with a particle size average of 52 nm. Compared to the pristine of ZnO NRs, the modified Pd/ZnO NRs (Xe) enhanced the photocatalytic activity about 21 %. This improvement might be due to the effect of Pd NPs that increase the light absorbance and the number of free radicals to degrade the methylene blue structure.