Semiconductor nanocrystals or quantum dots are becoming increasingly popular in research fields as wide ranging as cancer therapies, solar energy and disease detection. Colloidal synthesis provides a low-cost method of producing high quality quantum dots with narrow size distributions. The controllable nature of colloidal synthesis allows researchers to design the size, shape and surface functionalization of the resulting particles.
Here we investigate a simple low temperature method to produce CdSe quantum dots. The quantum dots were grown in solution by dissolving the CdO precursor in a mixture of macadamia oil, and oleic acid. Elemental Se was heated separately before the two mixtures were combined under an inert atmosphere. The injection temperature, reaction temperature and oleic acid concentration were all varied.
Optical absorption and photoluminescence spectroscopies showed the size of the quantum dots increased with time, temperature and oleic acid concentration. Dynamic light scattering has shown the hydrodynamic particle size to range from 7 to 22nm and the samples for up to 6 months.