Synthesis and characterization of CdSe nanocrystals

In this study, CdS,CdSe, and CdSe/CdS nanoparticles were synthesized in aqueous solutions. Firs of all, CdSe nanoparticles were produced under water-bath, using Se powder as a selenium source and by Se combined with Cd+2 ions by water-gas reaction at 75ºC. Secondly, CdS nanoparticles were obtained at 75ºC, using H2S generated by the reaction of Na2S-H2SO4 as a sulfur source and by S combined with Cd+2 ions by water-gas reaction. The synythesis time of every step was about 20 min. Lastly, these two steps were generated in the same solution respectively and the possibility of generating of CdSe/CdS nanoparticles and core/shell structure was showed. The obtained results were characterized by using TEM and UV-visible spectrophotometry and compared with litterateur.