Synthesis and properties of water-soluble CdSe/ZnS nanocrystals with the type-I core/shell structure

Abstract

The synthesis of CdSe/ZnS core/shell nanocrystals though aqueous phase using the coprecipitation method was reported. The influences of factors such as injection methods and dosages of precursors, reaction duration of water-bathing and the initial CdSe:ZnS molar ratio were discussed. In comparison to the CdSe plain core nanocrystals, the CdSe/ZnS core/shell nanocrystals show much brighter photoluminescence demonstrated by the photoluminescence spectra. The epitaxial growth of the core/shell structures was verified by TEM and XRD.

Keywords

nanocrystals / CdSe/ZnS core/shell / synthesis of aqueous phase / fluorescence

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