3D Triptycene‐Fused Acridine Electron Donor Enables High‐Efficiency Nondoped Thermally Activated Delayed Fluorescent OLEDs
Qun Zhan, Chen Cao, Taian Huang, Changjiang Zhou, Ziyang Xie, Yang Zou, Chun‐Sing Lee, Chuluo Yang
Abstract
Abstract Organic light‐emitting diodes (OLEDs) with simple nondoped device structure are extremely attractive for real applications since excitons can be utilized without considering the possible charge trapping and morphology issues in the host–dopant systems. Emitters with suppressed concentration annihilation capability are essential for nondoped devices. Herein, two thermally activated delayed fluorescence (TADF) emitters based on a novel 3D electron donor, namely, TDMAC, are constructed. The TDMAC donor consists of a conventional donor with fused triptycene scaffold. Benefitting from the unique rigid and bulky triptycene moiety, these TADF emitters exhibit excellent thermal, morphological, and photophysical properties. Consequently, highly efficient OLEDs with external quantum efficiencies up to 24.2% and 23% are realized for doped and nondoped devices, respectively.