Presentation Information

[22p-13M-1]Efficient Metal Free Deep–Blue Multi–Resonance Thermally Activated Delayed Fluorescence Emitter for High–Performance Organic Light–Emitting Diodes

〇(D)Rangani Wathsala Weerasinghe1, Subeesh M. Suresh2, David Hall2, Chin-Yiu Chan3, Youichi Tsuchiya1, Chihaya Adachi1 (1.Dept. Appl. Chem., Kyushu Univ., 744 Motooka, Nishi, Fukuoka 819-0395, Japan, 2.EaStCHEM School of Chem., Univ. of St Andrews, St Andrews, KY16 9ST, UK, 3.Dept. Materials Science and Engineering, City Univ. of Hong Kong, Hong Kong)

Keywords:

Organic Light Emitting Diode (OLED),Multiple Resonance Thermally Activated Delayed Fluorescence (MR-TADF),BT-2020 Standard

To achieve high-quality Ultra High-Definition (UHD) display the color gamut on the CIE coordinate in OLEDs should be expanded aiming the BT.2020 color standards is required. However, broadband-emitting conventional thermally activated delayed fluorescence (TADF) emitters satisfying CIEy= 0.046 are seldom reported. Narrowband emitting Multiple resonance (MR) TADF emitters are promising candidates for saturated colors but often have low reverse intersystem crossing rates (kRISC), impacting device performance. Furthermore, achieving the BT.2020 color standard for blue pixels with a high external quantum efficiency (EQE) and narrowband emission still remains a challenge, even for MR-TADF emitters. This study focuses on developing and application of a helical MR-TADF emitter, f-DOABNA, to address challenges in achieving BT.2020 standards for blue pixels, while addressing the low kRISC issue exhibited in MR-TADF emitters. f-DOABNA exhibited deep blue emission, a high photoluminescent quantum yield, and an exceptional kRISC. The OLED utilizing f-DOABNA achieves a high external quantum efficiency and meets BT.2020 standards, indicating its potential application in UHD displays.