Red/Near-Infrared Thermally Activated Delayed Fluorescence OLEDs with Near 100 % Internal Quantum Efficiency

Jia Xiong Chen, Wen Wen Tao, Wen Cheng Chen, Ya Fang Xiao, Kai Wang, Chen Cao, Jia Yu, Shengliang Li, Feng Xia Geng, Chihaya Adachi, Chun Sing Lee, Xiao Hong Zhang

Research output: Contribution to journalArticlepeer-review

237 Citations (Scopus)


Developing red thermally activated delayed fluorescence (TADF) emitters, attainable for both high-efficient red organic light-emitting diodes (OLEDs) and non-doped deep red/near-infrared (NIR) OLEDs, is challenging. Now, two red emitters, BPPZ-PXZ and mDPBPZ-PXZ, with twisted donor–acceptor structures were designed and synthesized to study molecular design strategies of high-efficiency red TADF emitters. BPPZ-PXZ employs the strictest molecular restrictions to suppress energy loss and realizes red emission with a photoluminescence quantum yield (ΦPL) of 100±0.8 % and external quantum efficiency (EQE) of 25.2 % in a doped OLED. Its non-doped OLED has an EQE of 2.5 % owing to unavoidable intermolecular π–π interactions. mDPBPZ-PXZ releases two pyridine substituents from its fused acceptor moiety. Although mDPBPZ-PXZ realizes a lower EQE of 21.7 % in the doped OLED, its non-doped device shows a superior EQE of 5.2 % with a deep red/NIR emission at peak of 680 nm.

Original languageEnglish
Pages (from-to)14660-14665
Number of pages6
JournalAngewandte Chemie - International Edition
Issue number41
Publication statusPublished - Oct 7 2019

All Science Journal Classification (ASJC) codes

  • Catalysis
  • Chemistry(all)


Dive into the research topics of 'Red/Near-Infrared Thermally Activated Delayed Fluorescence OLEDs with Near 100 % Internal Quantum Efficiency'. Together they form a unique fingerprint.

Cite this