文献类型：期刊文献

英文题名：Asymmetrical carbazole-b enzonitrile-base d TADF emitters designe d by alternate donor-acceptor strategy

作者：Lu, Zhaoyue[2];Chai, Tiantian[1];Jin, Yichao[2];Wang, Xiao[2];Zou, Ye[3];Zhang, Lijiang[2];Feng, Jiankang[1];Zhang, Mengtong[1];Wang, Shuo[1];Lu, Chichong[4];Jin, Guofan[1]

机构：[1]Jiangsu Univ, Sch Pharm, Zhenjiang 212013, Peoples R China;[2]East China Univ Sci & Technol, Sch Phys, Shanghai 200237, Peoples R China;[3]Chinese Acad Sci, Inst Chem, Lab Organ Solids, Beijing 100190, Peoples R China;[4]Beijing Technol & Business Univ, Coll Light Ind Sci & Engn, Dept Chem, Beijing 100048, Peoples R China

年份：2025

卷号：36

期号：6

外文期刊名：CHINESE CHEMICAL LETTERS

收录：;WOS:【SCI-EXPANDED(收录号:WOS:001458097000001)】；

基金：This work was financially supported by the National Natural Science Foundation of China (Nos. T2441002 and 22175186) .

语种：英文

外文关键词：Delayed fluorescence; Linear D-A-D structure; Localized excited state; Delocalized charge transfer state; Spin-orbital coupling

摘要：A pair of asymmetric rigid carbazole-benzonitrile-based emitters were synthesized by strategically alternating donor and acceptor groups along the molecular edges. The spin-flip process is accelerated by both the formation of localized and delocalized charge transfer states due to linearly positioned donors and strong spin-orbital coupling between different excitation feature of the lowest singlet and triplet excited states. This molecular architecture results in a remarkable short delayed lifespan of around 100 ns. The application of the two emitters in organic light-emitting diodes (OLEDs) achieves the highest external quantum efficiencies of 13.0 % for the green emitter and 9.1 % for the sky-blue emitter. Impressively, these devices maintain their high efficiency even at high luminance levels. The sustained efficiency is ascribed to the effective suppression of exciton quenching by substantially shortening delayed lifespan. These findings underscore the practical utility of the molecular design strategy that incorporates alternate donor and acceptor groups at the molecular periphery for shortening delayed fluorescence lifetime, and hold great promise for the development of high-performance OLEDs. (c) 2025 Published by Elsevier B.V. on behalf of Chinese Chemical Society and Institute of Materia Medica, Chinese Academy of Medical Sciences.