Tailor-Made Multi-Resonance Terminal Emitters toward Narrowband, High-Efficiency, and Stable Hyperfluorescence Organic Light-Emitting Diodes

摘要

Multi-resonance emitters (MREs) are a promising candidate for fulfilling theharsh requirements of display applications due to their unique photophysicalproperties. Recently, MREs have been widely used as a terminal emitter inhyperfluorescence organic light-emitting diodes (HF-OLEDs); however, sinceMREs are always thermally activated delayed fluorescence (TADF)-active,possessing long triplet lifetimes in millisecond order, they result in severechemical degradation. Instead of shortening the delayed lifetime of MREs bymolecular design, herein, a low-triplet pyrene unit is introduced into an MREscaffold to achieve narrowband emission and quick removal of triplets inMREs simultaneously. Blue HF-OLED based on the non-TADF MRE demonstratesa high external quantum efficiency of 20 and a tenfold improvementin stability, compared to those of the HF-OLEDs with standard MREs. Anopposite direction of molecular design of MREs for the sophisticated excitongeneration and transfer system in HF-OLEDs is proposed to enhance devicelifetime without sacrificing color purity and efficiency.