Influence of polymer coating on the low-temperature photoluminescence properties of ZnO nanowires

We report on low temperature photoluminescence studies of ZnO nanowires embedded in different polymers. Comparing the spectra of as-grown and embedded ZnO nanowires, we find a decrease of the deep-level emission and an increase of the near band-edge emission after the embedding process. The near band-edge emission of the embedded ZnO nanowires is dominated by a surface exciton band. The observed effects are independent of the selected polymer. The decrease of the deep-level emission scales with the balling abilities of the different polymers. We propose a model to explain the spectral changes. (c) 2008 American Institute of Physics.