[18a-M_B104-1~10] 12.4 Organic light-emitting devices, organic transistors, and flexible devices

10:45 AM - 11:00 AM JST(1:45 AM - 2:00 AM UTC)

[18a-M_B104-7] Operando ESR investigation of charge states in up-conversion OLEDs

〇Tsubasa Okamoto^1,2, Takehisa Isozumi¹, Shintaro Kiyofuji¹, Ryohei Yoshino³, Seiichiro Izawa³, Kazuhiro Marumoto^1,2,4 (1.Dep. Mater. Sci., Univ. Tsukuba, 2.OIQSST, Univ. Tsukuba, 3.Science Tokyo, 4.TREMS, Univ. Tsukuba)

Keywords:

organic light emitting diode,electron spin resonance,triplet-triplet annihilation

Recently, the development of ultra-low-voltage organic light-emitting diodes (UC-OLEDs) that utilize up-conversion (UC) emission via triplet-triplet annihilation has been rapidly progressing. In order to propose guidelines for optimizing device structures and improving device performance, it is important to investigate the states of charge carriers and excitons, which are responsible for emission, under actual device-operating conditions. In this presentation, we report a microscopic analysis of the charge states inside UC-OLEDs using operando electron spin resonance (ESR) spectroscopy. The results provide insight into the behavior of charge carriers and contribute to a deeper understanding of device performance.