Search

The formation mechanism of Cd–S–Se quantum dots (QDs) with a CdS/CdSe core–shell structure within a silicate glass system was investigated by monitoring the change in the first excitonic absorption peak of CdSe, CdS, and Cd–S–Se QDs as a function of the heat‐treatment (HT) duration. When a silicate glass containing QD formation components for CdSe or CdS single‐phased QDs was heat‐treated, CdSe QDs grew via Ostwald ripening, whereas CdS QDs hardly formed within the given silicate glass matrix. When the glass, including CdO, ZnSe, and ZnS, was utilized for the synthesis of Cd–S–Se QDs within the glass matrix, Cd–S–Se QDs were successfully formed and exhibited similar growth behavior to CdSe QDs during the initial stage of HT. The structural changes in the QD‐embedded glasses during HT were also monitored by Raman spectroscopy and discussed, and a possible formation mechanism of CdSe/CdS core–shell‐structured QDs within silicate glasses is suggested. [ABSTRACT FROM AUTHOR]

Se2− color centers and CdSe/Cd1−xZnxSe quantum dots (QDs) were formed in silicate glasses, respectively, by carefully adjusting the content of Al2O3. The absorption coefficient and broad visible emission at 400‐700 nm of Se2− color centers increased firstly and then decreased upon increasing concentration of Al2O3 from 0 to 5 mol. %. With 2 mol. % Al2O3 adding, the band edge emission centered at 497 nm from CdSe QDs in glasses was observed after heat treatment. Raman spectra and TEM characterization confirmed the formation of CdSe/Cd1−xZnxSe QDs. The small amount addition of Al2O3 had a significant effect on the formation of Se2− color centers and precipitation of CdSe/Cd1−xZnxSe QDs in glasses due to its complicated effect on the network structure and optical basicity of the glasses. [ABSTRACT FROM AUTHOR]