Direct synthesis of Zn_1−xCd _xS (0⩽x⩽1) quantum dots in aqueous solution and application in biology

Abstract

A simple procedure was presented to directly synthesize Zn_1−xCd _xS (0⩽x⩽1) quantum dots (QDs) in aqueous solution. QDs’ structures and properties were characterized by TEM (transmission electron microscopy), XRD (X-ray diffraction) and fluorescence microscopy. For those as-synthesized Zn_1−xCd _xS QDs, when the molar ratio between Zn and Cd changed from 1 to 0, its photoluminescence (PL) emission peak shifted from 430 nm to 675 nm. PL emission quantum efficiency was up to 15%. The experiment results demonstrated that those alloyed QDs showed a good biocompatibility and could be used as labelling materials in cell biology.

Keywords

Zn_1−xCd _xS / quantum dot / luminescence / synthesis

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