Colloidal ZnSe, ZnSe/ZnS, and ZnSe/ZnSeS Quantum Dots Synthesized from ZnO.

Abstract

Luminescence D 6540 Colloidal ZnSe, ZnSe/ZnS, and ZnSe/ZnSeS Quantum Dots Synthesized from ZnO. -Colloidal ZnSe quantum dots are synthesized from ZnO powder in a lauric acid/hexadecylamine mixture. The quantum dots show controlled photoluminescence emission from 400 to 440 nm with quantum yields from 6 to 10% at room temperature. By coating ZnSe with ZnS the photoluminescence quantum yield of ZnSe/ZnS quantum dots increases ca. 4.5-fold, whereas ZnSeS coated ZnSe/ZnSeS quantum dots exhibit ca. 3.8-fold increased photoluminescence quantum yields. The results show a potential for the preparation of colloidal ZnSe, ZnSe/ZnS, and ZnSe/ZnSeS quantum dots from cheap and nontoxic ZnO. -(CHEN*, H.-S.; LO, B.; HWANG, J.-Y.; CHANG, G.-Y.; CHEN, C.-M.; TASI, S.-J.; WANG, S.-J.

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White LED Based on YAG : Ce,Gd Phosphor and CdSe–ZnS Core/Shell Quantum Dots

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