Amplifying Circularly Polarized Luminescence with High Dissymmetry Factor over 10 ⁻² Based on Robust Point Chirality Triptycene Derivatives

Abstract

Abstract Chiral organic luminescent materials are promising candidates as direct emitting layers (EMLs) in circularly polarized organic light‐emitting diodes (CP‐OLEDs). However, most conventional systems suffered poor thermal stability of chiral configurations and low luminescent dissymmetry factors. Herein, we reported a pair of triptycene‐bridged enantiomers with a point chirality and a donor–acceptor architecture. Robust point chirality, originating from quaternary bridgehead‐carbons, prevented the common racemization during thermal sublimation. Thanks to the reduced electric transition dipole moment (µ e ) in donor–acceptor architecture, tuned parallel alignment between the further reduced µ e and magnetic transition dipole moment (µ m ) in the exciplex emitter, and the utilized chiral exciplex host for energy transfer to phosphor, the corresponding dissymmetry factors of emitters were sequentially amplified from 3.3 × 10 −4 to 4.5 × 10 −3 , and to 8.1 × 10 −3 . Remarkably, the CP‐OLED device simultaneously achieved outstanding electroluminescence performance with a high external quantum efficiency of 31.8% and a large dissymmetry factor of 2.2 × 10 −2 . This work provided a viable pathway for developing high‐performance CP‐OLED materials through synergistic structural, material, and device engineering.