A Tetrahedral Bisacridine Donor Enables Fast Radiative Decay in Thermally Activated Delayed Fluorescence Emitter

Ranran Pei; Yulin Xu; Jingsheng Miao; Hao Peng; Zhanxiang Chen; Changjiang Zhou; He Liu; Chuluo Yang

doi:10.1002/anie.202217080

A Tetrahedral Bisacridine Donor Enables Fast Radiative Decay in Thermally Activated Delayed Fluorescence Emitter

Angew Chem Int Ed Engl. 2023 Mar 20;62(13):e202217080. doi: 10.1002/anie.202217080. Epub 2023 Feb 16.

Authors

Ranran Pei¹, Yulin Xu¹, Jingsheng Miao¹, Hao Peng¹, Zhanxiang Chen¹, Changjiang Zhou², He Liu¹, Chuluo Yang¹

Affiliations

¹ Shenzhen Key Laboratory of New Information Display and Storage Materials, College of Materials Science and Engineering, Shenzhen University, Shenzhen, 518055, P. R. China.
² College of Chemical Engineering, Zhejiang University of Technology, Hangzhou, 310014, P. R. China.

PMID: 36722386
DOI: 10.1002/anie.202217080

Abstract

Achieving high efficiency and low efficiency roll-off simultaneously is of great significance for further application of thermally activated delayed fluorescent (TADF) emitters. A balance between radiative decay and reversed intersystem crossing must be carefully established. Herein, we propose a qunolino-acridine (QAc) donor composing two acridine with both planar (pAc) and bended (bAc) geometries. Combining with triazine, a TADF emitter QAc-TRZ is assembled. The pAc provides a well interaction with triazine which ensures a decent TADF behavior, while the bAc offers a delocalization of highest occupied molecular orbital (HOMO) which guarantees an enhancement of radiative decay. Remarkably, QAc-TRZ enables a highly efficient organic light emitting diode (OLED) with maximum external quantum efficiency (EQE) of 37.3 %. More importantly, the efficiencies under 100/1000 cd m^-2 stay 36.3 % and 31.7 %, respectively, and remain 21.5 % even under 10 000 cd m^-2 .

Keywords: Bisacridine; Delocalization; Organic Light Emitting Diodes; Thermally Activated Delayed Fluorescence.

Abstract

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