Synthesis of CdS-Capped CdSe Nanocrystals without any Poisonous Materials

CdS-capped CdSe nanocrystals (NCs) which show high luminescence quantum yield are synthesized without any Poisonous Materials in aqueous solution. The synthesis in an aqueous medium without any poisonous materials is attached importance to. The absorption spectroscopy and photoluminescence spectroscopy are employed to analyze the NCs. It takes 78s that the intensity decreases to the half for bare CdSe NCs, but 442s for CdSe/CdS core/shell NCs. The photo stability of CdSe NCs under 325nm laser irradiation is enhanced greatly after CdS overcoating.