Controllable surface-state emission from colloidal CdS quantum dots under different growth conditions.

High-quality colloidal photoluminescent CdS quantum dots (QDs) were synthesized in non-coordinating solvent octadecene (ODE) using oleic acid (OA) as capping molecule, and characterized by powered x-ray diffraction (XRD), transmission electron microscope (TEM), UV-Vis absorption spectra, photoluminescence (PL) emission spectroscopy and time-resolved emission spectroscopy. The effects of the growth time, the molar ratio of OA/Cd and Cd/S on the PL intensity from surface-state have been investigated. We found that the surface-state emission could be easily controlled by tuning the growth time and the molar ratio of Cd/S. [ABSTRACT FROM AUTHOR]