Highly efficient green and red narrowband emissive organic light-emitting diodes employing multi-resonant thermally activated delayed fluorescence emitters

Herein, we demonstrate how judicious selection of donor decorating a central multi-resonant thermally activated delayed fluorescence (MR-TADF) core based on DiKTa can lead to very high-performance OLEDs. Decorating the DiKTa core with triphenylamine (TPA) and diphenylamine (DPA), 3TPA-DiKTa and 3DPA-DiKTa exhibit bright, narrowband green and red emission in doped films, respectively. The OLEDs based on these emitters showed record-high performance with maximum external quantum efficiencies (EQEmax) for this family of emitters, with a EQEmax of 30.8% for 3TPA-DiKTa at λEL of 551 nm and 16.7% for 3DPA-DiKTa at λEL of 613 nm. The efficiency roll-off in the OLEDs was improved significantly by using 4CzIPN as an assistant dopant in hyperfluorescence (HF) devices. The outstanding device performance has been attributed to preferential horizontal orientation of the transition dipole moments of 3TPA-DiKTa and 3DPA-DiKTa.

Citation

Wu , S , Gupta , A K , Yoshida , K , Gong , J , Hall , D , Cordes , D B , Slawin , A M Z , Samuel , I D W & Zysman-Colman , E 2022 , ' Highly efficient green and red narrowband emissive organic light-emitting diodes employing multi-resonant thermally activated delayed fluorescence emitters ' , Angewandte Chemie International Edition , vol. 61 , no. 52 , e202213697 . https://doi.org/10.1002/anie.202213697

Publication

Angewandte Chemie International Edition

Status

Peer reviewed

DOI

https://doi.org/10.1002/anie.202213697

ISSN

1433-7851

Type

Journal article

Rights

Copyright © 2022 The Authors. Angewandte Chemie International Edition published by Wiley-VCH GmbH. This is an open access article under the terms of the Creative Commons Attribution License, which permits use, distribution and reproduction in any medium, provided the original work is properly cited.

Description

Funding: S. W. thanks the China Scholarship Council (201906250199). A. K. G. is grateful to the Royal Society for Newton International Fellowship NF171163. EZ-C and IDWS acknowledge support from EPSRC (EP/L017008, EP/P010482/1). We are also grateful for financial support from the University of St Andrews Restarting Research Funding Scheme (SARRF) which is funded through the Scottish Funding Council grant reference SFC/AN/08/020. EZ-C is a Royal Society Leverhulme Trust Senior Research fellow (SRF\R1\201089). We would also like to thank the Leverhulme Trust (RPG-2016-047) for financial support.