Au纳米颗粒和CdTe量子点复合体系发光增强和猝灭效应

Enhancement and quenching of photoluminescence from Au nanoparticles and Cd Te quantum dot composite system

利用金属蒸发真空多弧离子源注入机,将Au离子注入到高纯石英玻璃来制备镶嵌有Au纳米颗粒的衬底材料,随后将化学方法合成的CdTe量子点旋涂在玻璃衬底上制备了Au纳米颗粒和CdTe量子点复合体系.通过对镶嵌有Au纳米颗粒的衬底进行热退火处理来控制Au纳米颗粒的生长和分布,系统研究了Au纳米颗粒的局域表面等离子体共振对CdTe量子点光致发光性能的影响.利用光学吸收谱、原子力显微镜、透射电子显微镜和光致发光谱对样品进行了表征和测试.光致发光谱表明,Au纳米颗粒的局域表面等离子体对CdTe量子点的发光有增强效应也有猝灭效应.深入分析了Au纳米颗粒和CdTe量子点之间的相互作用过程,提出了关于Au-CdTe纳米复合体系中CdTe发光增强和猝灭的新机理.该实验结果为利用金属纳米颗粒表面等离子体技术制备高发光性能的光电子器件提供了较好的参考.

New composite systems consisting of Au nanoparticles （NPs） and CdTe quantum dots （QDs） are fabricated by spin coating chemically synthesizing CdTe QDs on silica substrates which have already been implanted by Ag ions through using a metal vapor vacuum arc （MEVVA） ion source implanter. By thermally annealing the Au ions implanted silica substrates, the growth and redistribution of Au NPs can be controlled, the influence of localized surface plasmon （LSP） of Au NPs on the photoluminescence （PL） of CdTe QDs is well studied. The optical properties, surface morphologies, microstructures, and light emission properties of the Au-ion implanted samples are investigated by using optical ab- sorption spectroscopy, atomic force microscopy, transmission electron microscopy and PL spectra measurements. PL spectra show that the PL intensities from Au NPs and CdTe QDs composite systems can be enhanced or quenched compared with those of CdTe QDs directly spin coated on bare silica substrate. The underlying interaction processes between Au NPs and CdTe QDs are discussed in depth, and the new mechanisms for the PL enhancement and quenching in the Au-CdTe coupled systems are put forward. These results provide a good reference for the future designing of optoelectronic devices with improved 1 efficiency by LSP of metal NPs