Stability and dispersion improvement of quantum-dot films by hydrosilylation between quantum-dot ligands and a siloxane matrix

Abstract

Quantum-dot (QD) ligands were modified and hydrosilylated with a siloxane matrix to improve the quantum efficiency and stability of the QDs. Conventional oleic acid (OA) ligands were exchanged with vinyl ligands without any reduction in the quantum yield. After ligand modification, hydrosilylation was induced between the vinyl ligands on the QDs (vinyl QDs) and a siloxane matrix, resulting in a uniform QD dispersion in the matrix. The hydrosilylated QDs in siloxane showed 23% higher photoluminescence intensity than OA QDs blended in siloxane after storage for 30 days at 85 °C under 85% relative humidity. The QDs also showed 22.3% higher UV/thermal stability than OA QDs in siloxane after 29 h under a high LED photon flux. This study demonstrates that the chemical reaction of QD ligands with polymer matrices can improve the QDs' dispersion and stability.