[11p-S222-1~13] 12.4 Organic light-emitting devices and organic transistors

[11p-S222-11] Operand electron spin resonance (ESR) spectroscopy of charge states in thermally activated delayed fluorescence (TADF) light-emitting diodes

〇Shintaro Yumoto¹, Junya Katsumata¹, Fumiya Osawa¹, Yoshimasa Wada², Katsuaki Suzuki², Hironori Kaji², Kazuhiro Marumoto^1,3 (1.Univ. Tsukuba, 2.Kyoto Univ., 3.TREMS, Univ. Tsukuba)

Keywords:organic light-emitting diodes, electron spin resonance

Thermally activated delayed fluorescence (TADF) has recently attracted much attention because all the excited states of TADF molecules in OLEDs can contribute to the light emission without any scarce heavy metal atoms in their molecular structures. In this study, we fabricated OLEDs and thin films with a TADF light-emitting material 3ACR-TRZ and a host material CBP, and we investigated the charge/exciton states in OLEDs during operand and thin films during UV-light irradiation using electron spin resonance (ESR) spectroscopy.