文献类型：期刊文献

英文题名：Design and Synthesis of Highly Luminescent Near-Infrared-Emitting Water-Soluble CdTe/CdSe/ZnS Core/Shell/Shell Quantum Dots

作者：Zhang, Wenjin;Chen, Guanjiao;Wang, Jian;Ye, Bang-Ce;Zhong, Xinhua[1]

机构：[1]E China Univ Sci & Technol, Dept Chem, State Key Lab Bioreactor Engn, Shanghai 200237, Peoples R China; E China Univ Sci & Technol, Sch Bioengn, Shanghai 200237, Peoples R China

年份：2009

卷号：48

期号：20

起止页码：9723

外文期刊名：INORGANIC CHEMISTRY

收录：;WOS:【SCI-EXPANDED(收录号:WOS:000270561400016)】；

基金：We thank the National Natural Science Foundation of China (No. 20771037), the Program for New Century Excellent Talents in University of China (NCET-06-0417), Pujiang Talents Project (07pj14032), Shuguang Project (06SG33), SRFDP (20070251014), the Program for Professor of Special Appointment at Shanghai Institutions of Higher Learning, and the National Special Fund for State Key Laboratory of Bioreactor Engineering (2060204) for financial support.

语种：英文

摘要：Applications of water-dispersible near-infrared (NIR)-emitting quantum dots (QDs) have been hampered by their instability and low photoluminescence (PL) efficiencies. In this paper, water-soluble highly luminescent NIR-emitting ON were developed through constructing CdTe/CdSe/ZnS core/shell/shell nanostructure. The CdTe/CdSe type-II structure yields the ON with NIR emission. By varying the size of CdTe cores and the thickness of the CdSe shell, the emission wavelength of the obtained nanostructure can span from 540 to 825 nm. In addition, the passivation of the ZnS shell with a substantially wide bandgap confines the excitons within the CdTe/CdSe interface and isolates them from the solution environment and consequently improves the stability of the nanostructure, especially in aqueous media. An effective shell-coating route was developed for the preparation of CdTe/CdSe core/shell nanostructures by selecting capping reagents with a strong coordinating capacity and adopting a low temperature for shell deposition. An additional ZnS shell was deposited around the outer layer of CdTe/CdSe QDs to form the core/shell/shell nanostructure through the decomposition of single molecular precursor zinc diethyldithiocarbamate in the crude CdTe/CdSe reaction solution. The water solubilization of the initially oil-soluble CdTe/CdSe/ZnS QDs was achieved through ligand replacement by 3-mercaptopropionic acid. The as-prepared water-soluble CdTe/CdSe/ZnS ON possess PL quantum yields as high as 84% in aqueous media, which is one of the best results for the luminescent semiconductor nanocrystals.