A new aqueos route for synthesizing selective size CdSe and core/shell CdSe/CdS Nanoparticles

CdSe and core/shell CdSe/CdS semiconductor nanoparticles were synthesized by chemical precipitation method in the aqueous media at room temperature.Property of this method is growth of CdSe nanocrystals specially in one set reaction, with increasing time of synthesis. The UV-Visible spectrum of CdSe shows that, the band edge absorption shift to higher wavelength with time duration of the reaction.the capping process has not lead to significant modification of the absorption spectra. Photoluminescence analyses are shown, wide emission band-width from 350 nm to 600 nm w.r.t. size of CdSe QDs, that, it is possible to produce LED colour lights.Emission intensity of CdSe/CdS is higher than CdSe core nanocrystals. The band-width of the emissions, varied with distribution of nanoparticle sizes. Also both cubic and hexagonal crystal structures are shown by XRD

Keywords:

semiconductor nanoparticles , aqueous chemical method , quantum dots , core/shell