Ag掺杂浓度对ZnO纳米花荧光增强的影响

Effects of Ag doping concentration on metal-enhanced fluorescence for ZnO nanoflowers

采用水浴与光照相结合的方法制备了Ag/ZnO纳米复合结构,研究了不同Ag掺杂浓度对ZnO发光强度的影响。通过X射线衍射(XRD)、扫描电子显微镜(SEM)和光致发光(PL)光谱对Ag/ZnO纳米复合物的结构、形貌和光学性能进行了研究。SEM表明,由水浴法制得的ZnO纳米花结构长约1.0μm,直径为200nm左右。XRD结果显示,Ag掺杂后Ag/ZnO纳米复合结构衍射峰的强度都增强,当掺杂浓度为0.153wt%时,在38.28°出现了Ag2O的衍射峰。PL表明,Ag浓度极大影响了ZnO紫外发光强度。当Ag的掺杂浓度为0.051wt%时,Ag/ZnO纳米复合结构具有最强的紫外发射强度,同未掺杂的ZnO相比,紫外发光强度提高了11倍。研究结果表明,利用Ag纳米颗粒的局域表面等离子共振(LSPR)特性增强了ZnO纳米结构的荧光强度,从而提高了荧光检测的灵敏度。

Ag/ZnO nano-composite structures were synthesized on n-type （100） Si substrates by Simple hydrothermal and photodeposition method. The effects of AN doping concentration on metal-enhanced fluorescence ZnO nanoflowers for are studied. The structure, morphology and optical properties of Ag/ZnO nano-composite structures have been characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM） and photoluminescence （PL） spectroscopy,respectively. The SEM results show that ZnO nanoflowers are about 1 tam in length and around 200 nm in diameter. The XRD patterns indicate that intensities of diffraction peaks of Ag/ZnO nano-composite structures are enhanced compared with undoped ZnO. The weak diffraction peak at 38. 28° can be assigned to Ag2O when the doping concentration of Ag is 0. 153 wt. %. The PL spectra demonstrate that the UV luminous intensity of ZnO is significantly influenced by the concentration of Pig. Ag/ZnO nano-composite structure has the strongest ultraviolet emission intensity when the doping concentration of Ag is 0. 051 wt. %. Compared with undoped ZnO,the UV luminous intensity of Ag/ZnO nano-composite structures is increased by 11 times due to the local surface plasma resonance （LSPR） effect of Ag nanoparticle. It is expected that the Ag/ZnO nano-composite structure can be used as a bilogical fluorescent probe to further improve the sensitivity and selectivity of fluorescence detection.