Dresden 2017 – wissenschaftliches Programm
Bereiche | Tage | Auswahl | Suche | Aktualisierungen | Downloads | Hilfe
CPP: Fachverband Chemische Physik und Polymerphysik
CPP 50: Poster: Organic Electronics and Photovoltaics, Molecular Excitations
CPP 50.16: Poster
Mittwoch, 22. März 2017, 18:30–21:00, P3
Thermally Activated Delayed Fluorescence studied by Electroluminescence Detected Magnetic Resonance — •Sebastian Weissenseel1, Nikolai Bunzmann1, Benjamin Krugmann1, Jeannine Grüne1, Stefan Väth1, Andreas Sperlich1, and Vladimir Dyakonov1,2 — 1Experimental Physics VI, Julius Maximilian University of Würzburg, 97074 Würzburg — 2Bayerisches Zentrum für Angewandte Energieforschung (ZAE Bayern), 97074 Würzburg
The mechanism of thermally activated delayed fluorescence (TADF) in organic light emitting diodes (OLEDs) raised many questions with respect to the spins of the emitting exciplex states. In particular, whether the TADF mechanism is a spin-dependent process and, if yes, what is the mechanism of the triplet-singlet Up to now spin-sensitive measurements for OLED devices are scarcely presented in literature. Here, we investigate TADF OLEDs by electroluminescence detected magnetic resonance (ELDMR) in devices based on 4,4’,4”-Tris(N-3-methylphenyl-N-phenyl-amino)triphenylamine (m-MTDATA): Tris(2,4,6-trimethyl-3-(pyridin-3-yl)phenyl)borane (3TPYMB) exciplexes. The triplet states of this system energetically split in an external magnetic field. Microwave radiation, applied by a stripline, is absorbed at a resonant magnetic field and enhances the intensity of electroluminescence. Modifying experimental conditions, e.g. resonance frequency, temperature or microwave power, leads to detailed knowledge of the spin system and the underlying mechanism of the reverse intersystem crossing. This information will assist designing new cost-effective OLED materials.