Enhanced photoluminescence of ZnO nanorods via coupling with localized surface plasmon of Au nanoparticles

We demonstrated the synthesis of ZnO nanorods by using a facile solution route at low temperature. Au nanoparticles were deposited on the surface of ZnO nanorods by an in-situ solution method. The ZnO nanostructures had nanorod-like morphology in large quantity and possessed high crystallinity. An enhancement of ultraviolet emission of ZnO nanorods was observed as a result of Au nanoparticles decoration, while green emission was suppressed. This excellent photoluminescence performance is attributed to surface-plasmon-mediated quenching of defect emission and the enhancement of band-edge emission. The defect transition energy (green) of ZnO nanorods is in resonance with the localized surface plasmon energy of the Au nanoparticles, which led to the conversion of deep level green emission into band-edge ultraviolet emission.