Enhancement of near-band edge emission of Au/ZnO composite nanobelts by surface plasmon resonance

Abstract

In this paper, ZnO nanobelts were synthesized by chemical vapor deposition. And then Au nanoparticles were sputtered on the ZnO nanobelts. Enhancement of the near-band edge emission of Au/ZnO composite nanobelts was observed from photoluminescence measurement due to the coupling between the defect emission from ZnO and surface plasmons of Au nanoparticles, compared to bare ZnO nanobelts. The coupled energy could be transferred into free space photons when the interface is sufficiently rough to scatter the surface plasmons. The enhancement ratio of the near-band edge emission of Au/ZnO is 11-fold higher than that of bare ZnO. The enhancement mechanism was proposed based on scattering and absorption by Au nanoparticles.