In Situ Synthesis of Thiol-Capped CuInS2-ZnS Quantum Dots Embedded in Silica Powder by Sequential Ligand-Exchange and Silanization

Abstract

Thiol-capped CuInS2-ZnS core-shell quantum dot (QD) embedded in silica powder is synthesized by in situ approach, which contributes to facileness, high reproducibility and mass-productivity. The proposed method is distinguished in that it uses intermediate ligand-exchange step with hydroxyl-terminated ligands during growth stage, which helps the QDs to be dispersed in polar silane matrix to form micron-sized silica powder. This results in well-dispersed QDs in the silica powder with luminescence efficiency of 34%. In addition, the QDs/silica composites are applied to white-LEDs, demonstrating high quality white light with high color stability under various operating currents.