Perovskite quantum dots with potassium oleate ligands for light-emitting diode applications

Lead tri-halide perovskite quantum dots (PeQDs) have attracted attention as a light source such as LEDs. However, this causes a decrease in not only their dispersibility but also photoluminescence quantum yield (PLQY), which is one of the factors for external quantum efficiency (EQE) of LEDs when the ligand as an insulating component is removed. Herein, we proposed a strategy to prepare PeQDs, which selectively coordinated potassium oleate on the surface of PeQDs. As a result, PeQDs were successfully prepared, while maintaining the dispersibility and high PLQY after removing the ligands and achieving improved EQE.