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All-organic thermally activated delayed fluorescence materials for organic light-emitting diodes

Nature Reviews Materials volume 3, Article number: 18020 (2018) Cite this article

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Abstract

Thermally activated delayed fluorescence (TADF) emitters, which produce light by harvesting both singlet and triplet excitons without noble metals, are emerging as next-generation organic electroluminescent materials. In the past few years, there have been rapid advances in molecular design criteria, our understanding of the photophysics underlying TADF and the applications of TADF materials as emitters in organic light-emitting diodes (OLEDs). This topic is set to remain at the forefront of research in optoelectronic organic materials for the foreseeable future. In this Review, we focus on state-of-the-art materials design and understanding of the photophysical processes, which are being leveraged to optimize the performance of OLED devices. Notably, we also appraise dendritic and polymeric TADF emitters — macromolecular materials that offer the potential advantages of low cost, solution processable and large-area OLED fabrication.

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Figure 1: Mechanism of TADF OLEDs.
Figure 2: External quantum efficiencies of TADF emitters.
Figure 3: Chemical structures of representative acceptors, donors and TADF small molecules.
Figure 4: The performance of small-molecule TADF OLEDs.
Figure 5: Molecular structures of TADF dendrimers.
Figure 6: Molecular structures of TADF polymers.
Figure 7: Device structure of TADF polymer OLEDs.

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Acknowledgements

The financial support of the National Natural Science Foundations of China under Grant Nos. 51521062 and 21274009 (Z.R. and S.Y.) and the Engineering and Physical Sciences Research Council (EPSRC) Grant No. EL/L02621X/1 (M.R.B.) is gratefully acknowledged.

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Authors and Affiliations

  1. Beijing Advanced Innovation Center for Soft Matter Science and Engineering, State Key Laboratory of Chemical Resource Engineering, Beijing University of Chemical Technology, Beijing, China

    Yuchao Liu, Chensen Li, Zhongjie Ren & Shouke Yan

  2. Department of Chemistry, Durham University, Durham, UK

    Martin R. Bryce

  3. These authors contributed equally: Yuchao Liu, Chensen Li,

    Yuchao Liu & Chensen Li

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  1. Yuchao Liu
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Liu, Y., Li, C., Ren, Z. et al. All-organic thermally activated delayed fluorescence materials for organic light-emitting diodes. Nat Rev Mater 3, 18020 (2018). https://doi.org/10.1038/natrevmats.2018.20

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