Title data
Naqvi, Bilal A. ; Schmid, Markus ; Crovini, Ettore ; Sahay, Prakhar ; Naujoks, Tassilo ; Rodella, Francesco ; Zhang, Zhen ; Strohriegl, Peter ; Bräse, Stefan ; Zysman-Colman, Eli ; Brütting, Wolfgang:
What Controls the Orientation of TADF Emitters?
In: Frontiers in Chemistry.
Vol. 8
(2020)
.
- 750.
ISSN 2296-2646
DOI: https://doi.org/10.3389/fchem.2020.00750
Abstract in another language
Thermally-activated delayed fluorescence (TADF) emitters—just like phosphorescent ones—can in principle allow for 100 internal quantum efficiency of organic light-emitting diodes (OLEDs), because the initially formed electron-hole pairs in the non-emissive triplet state can be efficiently converted into emissive singlets by reverse intersystem crossing. However, as compared to phosphorescent emitter complexes with their bulky—often close to spherical—molecular structures, TADF emitters offer the advantage to align them such that their optical transition dipole moments (TDMs) lie preferentially in the film plane. In this report, we address the question which factors control the orientation of TADF emitters. Specifically, we discuss how guest-host interactions may be used to influence this parameter and propose an interplay of different factors being responsible. We infer that emitter orientation is mainly governed by the molecular shape of the TADF molecule itself and by the physical properties of the host—foremost, its glass transition temperature T<sub>g</sub> and its tendency for alignment being expressed, e.g., as birefringence or the formation of a giant surface potential of the host. Electrostatic dipole-dipole interactions between host and emitter are not found to play an important role.
Further data
Item Type: | Article in a journal |
---|---|
Refereed: | Yes |
Keywords: | OLEDs; TADF; emitter orientation; molecular orientation; emitter-host interaction |
Institutions of the University: | Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Professor Macromolecular Chemistry I Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Former Professors > Professor Macromolecular Chemistry I - Univ.-Prof. Dr. Peter Strohriegl Faculties Faculties > Faculty of Biology, Chemistry and Earth Sciences Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry Faculties > Faculty of Biology, Chemistry and Earth Sciences > Department of Chemistry > Former Professors |
Result of work at the UBT: | Yes |
DDC Subjects: | 500 Science > 540 Chemistry |
Date Deposited: | 11 Jul 2022 07:28 |
Last Modified: | 14 Jun 2023 11:06 |
URI: | https://eref.uni-bayreuth.de/id/eprint/70477 |