Quantum Yield Enhancement of Cd/Se Colloidal Quantum Dots by Variation of Surface Ligands.

摘要

Colloidal cadmium/selenium (Cd/Se) quantum dots (QDs) were synthesized with two different sets of ligands. The first used simple components, octadecene (ODE), which serves both as a solvent and a ligand, and oleic acid, which also serves as a ligand. The second used more complex ligands, octadecylphosphonic acid, and oleyamine. Transient samples have been collected during the course of each synthesis. Then the particle diameter and quantum yield (QY) of the samples were calculated from transmission and emission data obtained with UV/VIS spectrometer and flourometer. Calibration data for QY measurements were obtained with reference to the literature data on the QY of a known standard, rhodamine 6G (Rh6G). These measurements helped elucidate the effect surface ligands have on the QY of semiconductor colloidal QDs.