Photoluminescence of CdTe quantum dots ligated with caprylic acid synthesized at low temperature

Photoluminescent semiconductor nanocrystals or quantum dots (QDs) are usually produced using expensive ligands and solvents at high temperature above 280°C to ensure high-quality optical properties, particularly the photoluminescence of QDs. The reproducibility of highly stable photoluminescence in QD preparation, in most cases, varies depending on many effects, such as the ligand used and temperature. Here a facile preparation of photoluminescent semiconductor CdTe nanocrystals or quantum dots (QDs) is conducted in the presence of caprylic acid at moderate temperatures between 80–140°C, which are much lower than the high temperatures used in conventional organic-phase preparation of CdTe QDs. The results show that the optical properties of CdTe QDs depend considerably on the reaction time, temperature and ligand used.