Liu Liping, Peng Qing, Li Yadong
Department of Chemistry, Tsinghua University, Beijing 100084, China.
Inorg Chem. 2008 Apr 21;47(8):3182-7. doi: 10.1021/ic702203c. Epub 2008 Mar 4.
Nearly monodisperse CdSe quantum dots with blue emission are obtained through an oxidation approach, in which CdSe particles can be etched into smaller ones. During the oxidation process, CdSe with yellow emission (546 nm) can be rapidly oxidized to blue emission (466 nm) due to its incompletely crystallized structure. Further oxidation results in the slow blue-shift of the photoluminescence peak to 433nm. The quantum fluorescence efficiency of CdSe with blue emission is about 10%, and surface-trap emission becomes evident when the PL peak of CdSe reaches the blue-violet region, since the surface atom ratio increases. This oxidation route offers a simple and mild way to get extremely small CdSe quantum dots.
通过一种氧化方法可获得具有蓝色发射的近单分散CdSe量子点，在该方法中CdSe颗粒可被蚀刻成更小的颗粒。在氧化过程中，由于其结构结晶不完全，发射黄色光（546nm）的CdSe可迅速氧化为发射蓝色光（466nm）。进一步氧化导致光致发光峰缓慢蓝移至433nm。发射蓝色光的CdSe的量子荧光效率约为10%，当CdSe的PL峰达到蓝紫色区域时，表面陷阱发射变得明显，因为表面原子比例增加。这种氧化途径提供了一种简单温和的方法来制备极小的CdSe量子点。
