Thermally Activated Delayed Fluorescent Donor–Acceptor–Donor–Acceptor π-Conjugated Macrocycle for Organic Light-Emitting Diodes

Izumi, Saika; Higginbotham, Heather F.; Nyga, Aleksandra; Stachelek, Patrycja; Tohnai, Norimitsu; Silva, Piotr de; Data, Przemyslaw; Takeda, Youhei; Minakata, Satoshi

Abstract

A new class of thermally activated delayed fluorescent donor–acceptor–donor–acceptor (D–A–D–A) π-conjugated macrocycle comprised of two U-shaped electron-acceptors (dibenzo[a,j]phenazine) and two electron-donors (N,N′-diphenyl-p-phenyelendiamine) has been rationally designed and successfully synthesized. The macrocyclic compound displayed polymorphs-dependent conformations and emission properties. Comparative studies on physicochemical properties of the macrocycle with a linear surrogate have revealed significant effects of the structural cyclization of the D–A-repeating unit, including more efficient thermally activated delayed fluorescence (TADF). Furthermore, an organic light-emitting diode (OLED) device fabricated with the macrocycle compound as the emitter has achieved a high external quantum efficiency (EQE) up to 11.6%, far exceeding the theoretical maximum (5%) of conventional fluorescent emitters and that with linear analogue (6.9%).

Citation

Izumi, S., Higginbotham, H. F., Nyga, A., Stachelek, P., Tohnai, N., Silva, P. D., Data, P., Takeda, Y., & Minakata, S. (2020). Thermally Activated Delayed Fluorescent Donor–Acceptor–Donor–Acceptor π-Conjugated Macrocycle for Organic Light-Emitting Diodes. Journal of the American Chemical Society, 142(3), 1482-1491. https://doi.org/10.1021/jacs.9b11578

• Journal Article Type: Article
• Acceptance Date: Dec 1, 2019
• Online Publication Date: Jan 2, 2020
• Publication Date: Jan 22, 2020
• Deposit Date: Dec 7, 2020
• Journal: Journal of the American Chemical Society
• Print ISSN: 0002-7863
• Electronic ISSN: 1520-5126
• Publisher: American Chemical Society
• Volume: 142
• Issue: 3
• Pages: 1482-1491
• DOI: https://doi.org/10.1021/jacs.9b11578
• Public URL: https://durham-repository.worktribe.com/output/1255849