Abstract
Fluorescent semiconductor quantum dots (QDs) are nanocrystals with a diameter that usually ranges from 1 to 10 nm. QDs can be prepared by many techniques including plasma synthesis, mechanical fabrication, or colloidal synthesis. The current paper presents the synthesis of CdTe quantum dots (QDs) with wet chemical method at variable reaction time, variable temperature and variable trioctylphosphine (TOPO) concentration, to control the size of the produced QDs. Structural characterization was carried out with conventional transmission electron microscopy (TEM) and X-ray diffraction (XRD). Optical characterization was performed with optical spectrometer and Spectrofluorometre. TEM images revealed that the size of QDs increases with the increase in the three parameters' reaction time, temperature and TOPO concentration. This represents a new achievement in comparison to the previously produced similar QDs with random size ranges. Furthermore, the optical properties of the CdTe QDs showed that the characteristic emission and absorption of light could be controlled by changing these parameters as well. The observed results are very important and can be applied to increase the efficiency of solar cells.