A Diboron-Based Thermally Activated Delayed Fluorescent Material for Versatile Applications of Organic Light-Emitting Diodes

• Published in: ACS materials letters Vol. 5; no. 9; pp. 2339 - 2347
• Main Authors: Hsieh, Chia-Min, Chen, Yi-Kuan, Lei, Jian, Chou, Pang-Yu, Hsieh, Song-Ting, Ko, Chang-Lun, Hung, Wen-Yi, Wu, Tien-Lin, Cheng, Chien-Hong
• Format: Journal Article
• Language: English
• Published: American Chemical Society 04.09.2023
• ISSN: 2639-4979; 2639-4979
• DOI: 10.1021/acsmaterialslett.3c00626

Thermally activated delayed fluorescence (TADF) organic light-emitting diodes (OLEDs) have attracted public attention due to their high external quantum efficiency (EQE) and implication in future display technology. Despite their improved efficiency, TADF-based OLEDs still suffer from serious efficiency roll-off and short operational lifetimes. Herein, a diboron-based molecule, PhCzDBA, is designed and its device exhibits a maximum EQE (EQEmax) of 33.8% and only slight roll-off (EQEmax of 31.5% at 1000 cd m–2 and 28.8% at 3000 cd m–2). Furthermore, it shows superior stability among reported TADF devices (LT80 of 113 h at the initial luminance of 3000 cd m–2). Remarkably, its nondoped OLED shows a high EQEmax of 17.7% with a λmax > 580 nm, surpassing most orange nondoped OLEDs. Moreover, a decent white OLED device with an EQEmax of 16.4% and a color rendering index (CRI) of 73 can be achieved by incorporating a simple sandwich emitting layer configuration, exhibiting the potential and diverse applications in many aspects.