【摘要】 用L-半胱氨酸作为配体,直接水相合成了CdTe量子点和核壳结构CdTe/CdS量子点;实验研究了不同回流温度和回流时间下对CdTe量子点的光学性质的影响以及改善光稳定性的方法。利用紫外-可见吸收光谱和荧光光谱表征了CdTe和CdTe/CdS量子点的光学性质;CdTe量子点的荧光发射峰在525~565nm之间,且发射峰较窄;XRD、透射电镜(TEM)测试表明合成了物相较纯、分散性较好、尺寸均匀且粒径在2~3nm的CdTe量子点,但存在光稳定性差的缺点。制备核壳结构CdTe/CdS量子点的方法对所合成的CdTe量子点的光稳定性进行改善,通过荧光发射光谱、紫外吸收光谱、透射电镜(TEM)和XRD测试对CdTe/CdS核壳量子点的形貌和性能进行了表征。更多还原

【Abstract】 An aqueous phase synthesis of CdTe and CdTe/CdS core-shell quantum dots with use of L-cysteine as ligand was reported, and the influence of reflux time and temperature on the optical properties of Cd Te quantum dots was discussed, and capable method of improving the stability under light irradiation was proposed. The optical properties of quantum dots were studied using UV-visible absorption and fluorescence spectrometers. Results show that the prepared CdTe quantum dots have relatively narrow fluorescent emission bands with peaks in a range of 525~565 nm. The XRD and TEM characterizations indicate that the prepared Cd Te quantum dots possess pure phase and good dispersion with average particle size of 2~3 nm, but their photostability is much poor. Comparatively, the photostability can be improved significantly for the Cd Te/Cd S core-shell quantum dots. Comprehensive investigations on the CdTe/CdS core-shell quantum dots were carried out with UV-visible absorption, fluorescence, TEM and XRD characterizations.更多还原