Multifunctional oxadiazole-based ultraviolet-emitting materials used as hosts for multicolor phosphorescence

Abstract

Highly efficient ultraviolet materials and host materials for organic light-emitting diodes (OLEDs) have been gaining increasing attention in recent years. In this study, three donor–acceptor (D–A) molecules with different HLCT properties were designed and synthesized using oxadiazole as an electron acceptor. Not only does the molecule m-PIOXZ exhibit efficient ultraviolet electroluminescence, but it can also serve as the host material for high-efficiency phosphorescent OLEDs (PhOLEDs) with low roll-off. As a result, high external quantum efficiency (EQE) and long operational lifetimes are obtained in green, yellow and red emissive PhOLEDs, providing new insights for developing high-efficiency, low roll-off, and full-color OLEDs.