硒化镉发光量子点的制备及其在有机发光器件中的应用

摘要

We have successfully synthesized high-quality CdSe/ZnS and Au/CdSe/ZnS quantum dots(QDs) by simple chemical colloid methods. We try to explore the possibility of PL intensity enhancement of CdSe QDs in presence of Au nanoparticles (NPs). Due to the existence of surface plasma excitation of core Au, we have observed a great enhanced PL intensity in the core-shell NPs of Au/CdSe/ZnS as compared to CdSe/ZnS NPs. Here, the optimal fraction of Au NPs incorporation into CdSe/ZnS NPs was found to be 0.1 mol% Au NPs, which shows the highest PL intensity. We also fabricated a high efficiency organic electroluminescent device (OLED) using CdSe/ZnS and Au/CdSe/ZnS with phosphorescent Ir-complex as light-emitting materials. The quantum efficiencies of OLEDs were enhanced about 2 times as compared to blank device.%硒化镉量子点具有随粒径尺寸改变,而产生发光波长调变的特性,目前已被广泛研究.本研究是由化学溶胶法合成不同粒径尺寸的核壳型CdSe/ZnS硒化镉量子点,其表面包覆十六烷基胺,避免分子团聚现象.在由硒化镉成核温度的控制,成功地制备一系列具有各种尺寸粒径的核壳型硒化镉量子点(2～6 nm).本研究也合成了含有纳米金粒子于核壳型硒化镉量子点,实验结果发现:硒化镉发光效率明显的提高.在有机发光器件的应用方面,将发光波长为505 nm核壳型 CdSe/ZnS量子点掺入溶有发光波长为570 nm铱化合物的氯仿溶液时,其溶液的光致发光光谱表明,原量子点的发光特性消失,只有铱化合物的发光依然存在,且其发光强度呈现明显增强趋势,我们推测此现象源自于量子点到铱化合物能量转移的机制.我们也以含有核壳型硒化镉量子点的铱化合物与PVK混合材料为发光层,成功的制作发光二极管器件,器件的发光效率因核壳型硒化镉的掺杂,明显提高2倍多.