Optical Properties Investigation of Core/Shell Quantum Dots by Low Temperature Synthesis

The core/shell structure semiconductor nanoparticle CdTe/CdS was synthesized in aqueous solution using thioglycolic acid as a stabilizer. UV-vis spectra, the fluorescence spectra of the series of CdTe, CdS QDs samples were also analyzed in detail, and the result indicates that the intensity of flourescence was increasing and the absorption and emission peaks had redshift regularly with the increasing of the reaction time. The XRD patterns proved that the CdS did not to form single core in the process of CdTe/CdS synthesis. The synthesized quantum dots(QDs) exhibit strong and stable band-edge luminescence. The optical properties of QDs can be improved when CdTe as a core was coated with CdS as a shell to form a core/shell QDs.