Abstract: ZnO nanowires were grown through CVD method, and SEM, TEM and PL spectroscopy system were used to characterize its morphology, crystal structure and optical properties. Due to the effect of Au SPR on ZnO nanowire, its PL spectra increased by 20 times at the UV region and decreased remarkably at the green region when it was coated by Au film. Through the annealing experiments, the competition mechanism between intrinsic transition and defect transition in ZnO material proved to be of great effect on its PL spectra. The results showed that the intrinsic transition of annealed ZnO nanowire decreased remarkably, while its defect transition increased. When coated by Au film, the PL spectra of annealed ZnO nanowire increased by almost 30 times at the UV region. The improvements are more remarkable than those reported results.

Key words: ZnO nanowire, PL spectra, light emission enhancement, Au surface plasmon resonance, annealing

摘要： 采用CVD方法在管式炉中生长了ZnO纳米线, 并通过SEM、TEM和PL光谱仪表征了其形貌、结构及光谱性质。利用Au表面等离激元共振与材料的相互作用, 在ZnO纳米线表面镀上Au膜, 发现其对ZnO纳米线的PL光谱有明显的改善, 纳米线本征发光增强20倍左右, 缺陷发光有显著的减弱。通过高温退火, 结果显示ZnO纳米线的本征发光和缺陷发光之间存在很强的竞争, 在入射光功率一定的条件下, 高温退火后ZnO纳米线的本征发光明显地减弱, 缺陷发光显著地增强。对退火后的ZnO纳米线镀上Au膜, 发现其本征发光增强了30倍左右。这些结果比现有的报道有显著提高。

关键词: ZnO纳米线, PL光谱, 发光增强, Au表面等离激元共振, 退火