Aqueous synthesis of glutathione-capped ZnSe and Zn_1-xCd _xSe alloyed quantum dots

The first aqueous synthesis of alloyed blue QDs (quantum dots) were presented and a new synthetic strategy that can be broadly applied towards large-scale, environmentally friendly production of composite and alloyed nanocrystals was reported. high-quality Zn_1-xCd_xSe nanocrystals with fluorescence emissions tunable in the blue range have been synthesized by incorporating a Cd precursor in ZnSe nanocrystals. The synthesis of ZnSe QD5 was based on the reaction of zinc chloride and sodium hydroselenide or hydrogen selenide, with glutathione as the stabilizer. The fluorescence emission peak of as-prepared ZnSe QDs was shifted from 350 to 370 nm in 60 mm, with the QY increasing from 2 to 22%. Different molar ratios of Cd precursor were introduced to the ZnSc nanocrystals at the same point in time, and were heated for the same duration to control the Cd molar fraction in the alloyed QDs.