A transparent and luminescent epoxy nanocomposite containing CdSe QDs with amido group-functionalized ligands

Abstract

A highly transparent and luminescent CdSe quantum dot (QD)/epoxy nanocomposite was prepared by mixing amido-functionalized QDs with an epoxy matrix. The original oleic acid ligand on the QDs was replaced by thioglycolic acid, and then primary amine groups were introduced via a reaction between the carboxyl group of thioglycolic acid and Schiff’s base. The QDs with amido-functionalized ligands showed a better dispersibility and higher optical properties in the epoxy matrix. It was found that the nanocomposite filled with 0.3 wt% modified green light-emitting QDs had a similar transparency to the neat epoxy and twice the luminescence intensity of nanocomposite-filled 0.3 wt% original QDs. Moreover, a QD/epoxy nanocomposite, which could emit clear white light by combining the unabsorbed blue excitation light and the re-emitted yellow light, was successfully fabricated by following the same strategy. The as-prepared QD/epoxy nanocomposite has potential applications in encapsulating materials in light-emitting diode.