Enhanced photoluminescence from zinc oxide by plasmonic resonance of reduced graphene oxide

Abstract

We demonstrate 2.79- and 10.16-fold enhanced photoluminescence (PL) from band-edge and defect levels of zinc oxide (ZnO) using a plasmonic resonance of reduced graphene oxide (RGO) in the UV frequency range. RGO shows superior tunability on the light absorption of ZnO by the confined plasmonic resonance, which results in strong PL emission. We conclude that the absorption of ZnO in close proximity to the RGO layer can be enhanced. These arguments are strongly supported by different PL enhancements depending on the distance between RGO and ZnO layers, time-resolved PL, and numerical calculations.