Quantum Yields and Time-Resolved Spectroscopy in CdSe and CdSe/ZnS Nanocrystals

We synthesized CdSe and CdSe/ZnS nanocrystals having various surface conditions by controlling the amounts of organic solvents and using the chemical colloidal method, and we measured their optical properties. We showed that the ZnS-capped CdSe nanocrystals exhibited a large enhancement of the fluorescence intensity, and that the eciency of the quantum yield and the decay times of photoluminescence changed. We observed the changes in photoluminescence decay times for various surface conditions of CdSe and CdSe/ZnS nanocrystals by using time-resolved spectroscopy.