Synthesis of Highly Luminescent Glass Incorporating Nanocrystals Through Sol-Gel Processing

摘要

Highly luminescent glass phosphor was prepared by embedding II- VI semiconductor nanocrystals in a glass matrix using a novel sol-gel process. Water-dispersible CdTe nanocrystals (3-6nm) used in this fabrication were stabilized by thioglycolic acid (TGA) through an aqueous method. Two coupling agents, mercaptopropyl silane (MPS) and aminopropyl silane (APS) have been selected as starting materials. In the case of MPS, nanocyrstals are dispersed homogeneously because of a thiol-group both in MPS and TGA on the CdTe surface. However, it takes a month to get a condensed polymer-like sample at room temperature. In contrast, an amino group in APS accelerates the sol-gel reaction drastically and connects with a carboxyl group in TGA. Therefore, the agglomeration of the CdTe nanocrystal were reduced during the sol-gel synthesis. The stable glass obtained emits light of various colors with high photoluminescence efficiency, and is thus a suitable phosphor material for light-emitting devices.