Microwave Synthesis of Water-Dispersed CdTe/CdS/ZnS Core-Shell-Shell Quantum Dots with Excellent Photostability and Biocompatibility

摘要

In the past decades, colloidal luminescent semiconductor nanocrystals, often referred to as quantum dots (QDs), attracted much attention due to their unique advantages over traditional fluorescent dyes, such as size-tunable emission, broad photoexcitation combined with narrow photoemission, strong fluorescence, and high resistance to photobleaching. It is well-known that high quality, water-dispersed QDs, i.e., QDs with a high photoluminescent quantum yield (PLQY), narrow full-width at half maximum (fwhm), excellent photostability, and favorable biocompatibility, are promising for many biological applications. Different kind of highly luminescent QDs can be prepared via organometallic routes, e.g., CdSe, CdSe/ZnS core-shell (CS), and CdSe/CdS/ZnS core-shell-shell (CSS) QDs with high PLQY (40-80%) which were successfully prepared in an organic phase. However, complicated manipulations are required to disperse these QDs in water, e.g., wrapping an amphiphilic polymer around the QDs or substituting the hydrophilic molecules for surface-binding TOPO molecules.