Abstract
This section covers both metal–organic and organic materials that feature thermally activated delayed fluorescence (TADF). Such materials are especially useful for organic light-emitting diodes (OLEDs), a technology that was introduced in commercial displays only recently. We compare both material classes to show commonalities and differences, highlighting current issues and challenges. Advanced spectroscopic techniques as valuable tools to develop solutions to those issues are introduced. Finally, we provide an outlook over the field and highlight future trends.
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Notes
It needs to be said that there are also organic TADF emitters in which ΔEST is not controlled by this, for example due to symmetry-related mechanisms [127].
References
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Acknowledgments
The authors thank the German Ministry for Education and Research (BMBF) for funding in the scope of the cyCESH project (FKN 13N12668). Funding through the Deutsche Forschungsgemeinschaft (TRR88, B2; SFB 1176) is acknowledged. We gratefully acknowledge the collaboration with the groups of Prof. Ifor Samuel (University of St. Andrews), Prof. Franky So (NCSU), Prof. Christopher Barner-Kowollik (KIT), Prof. Clemens Heske (KIT, UNLV), Prof. Uli Lemmer (KIT), and Manuela Wallesch (KIT) as well as the scientific division of CYNORA and the synchrotron facilities of KIT, Angstromquelle Karlsruhe (ANKA).
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This article is part of the Topical Collection “Photoluminescent Materials and Electroluminescent Devices”; edited by Nicola Armaroli and Henk Bolink.
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Bergmann, L., Zink, D.M., Bräse, S. et al. Metal–Organic and Organic TADF-Materials: Status, Challenges and Characterization. Top Curr Chem (Z) 374, 22 (2016). https://doi.org/10.1007/s41061-016-0022-6
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DOI: https://doi.org/10.1007/s41061-016-0022-6