Optimizing ZnO Nanorods Synthesis and Decoration with Au Nanoparticles for Enhanced Photo-Related Applications

ZnO nanorods with hexagonal structures were synthesized using a hydrothermal method under different conditions. The effect of synthesis parameters on ZnO growth wassystematically studied by scanning electron microscopy. The results demonstrated that themorphology and size of ZnO nanorods are influenced by nature of the solvent, zinc acetateconcentration, growth temperature and time. Rod-like and needle-shaped ZnO was producedwhen DI water and ethanol were used as the solvent, respectively. The concentration of precursors can also influence the formation of ZnO nanorods. Increasing growth time leads to rod-like diameter increment. ZnO nanorods with desired diameters were successfully prepared using 2.3 M zinc acetate concentration in DI water with a growing temperature of 80 ºC for 3 h.Next, Au/ZnO nanorod heterostructure was synthesized by a self-assembly of Au salt precursors and subsequent reduction of Au ions on ZnO nanorod surface without any surfactants or additives. Through SEM analysis, it was found that Au nanoparticles were uniformly deposited on the surface of ZnO nanorods. Compared with bare ZnO nanorods, Au/ZnO heterostructures exhibited characteristic surface plasmon absorption at 900 nm.