New electron-donating segment to develop thermally activated delayed fluorescence emitters for efficient solution-processed non-doped organic light-emitting diodes  

作　　者：Ming Zhang Gaole Dai Caijun Zheng Kai Wang Yizhong Shi Xiaochun Fan Hui Lin Silu Tao Xiaohong Zhang 

机构地区：[1]School of Optoelectronic Science and Engineering,University of Electronic Science and Technology of China(UESTC),Chengdu 610054,China [2]Institute of Functional Nano&Soft Materials(FUNSOM),Soochow University,Suzhou 215123,China

出　　处：《Chinese Chemical Letters》2022年第2期1110-1115,共6页中国化学快报（英文版）

基　　金：supported by the National Natural Science Foundation of China (Nos.51773029,52073040 and 51821002);the Fundamental Research Funds for the Central Universities (No.ZYGX2016Z010);the International Cooperation and Exchange Project of Science and Technology Department of Sichuan Province (No.2019YFH0057)。

摘　　要：Thermally activated delayed fluorescent(TADF) materials capable of efficient solution-processed nondoped organic light-emitting diodes(OLEDs) are of important and practical significance for further development of OLEDs. In this work, a new electron-donating segment, 2,7-di(9 H-carbazol-9-yl)-9,9-dimethyl-9,10-dihydroacridine(2 Cz-DMAC), was designed to develop solution-processable non-doped TADF emitters. 2 Cz-DMAC can not only simultaneously increase the solubility of compounds and suppress harmful aggregation-caused quenching, but also efficiently broaden the delocalization of the highest occupied molecular orbital and promote the reverse intersystem crossing process. Three new TADF emitters, 2-(2,7-di(9 H-carbazol-9-yl)-9,9-dimethylacridin-10(9 H)-yl)dibenzo[b,d]thiophene 5,5-dioxide(2 Cz-DMAC-BTB), 2-(2,7-di(9 H-carbazol-9-yl)-9,9-dimethylacridin-10(9 H)-yl)-9 H-thioxanthen-9-one(2 Cz-DMAC-TXO), 2-(2,7-di(9 H-carbazol-9-yl)-9,9-dimethylacridin-10(9 H)-yl)thianthrene 5,5,10,10-tetraoxide(2 Cz-DMAC-TTR), were developed by using 2 Cz-DMAC segment as the electron-donor. As anticipated, the solution-processed non-doped OLEDs employing 2 Cz-DMAC-BTB, 2 Cz-DMAC-TXO and 2 CzDMAC-TTR as the emitters respectively exhibited green, orange and red emissions with maximum external quantum efficiencies of 14.0%, 6.6% and 2.9%. These results successfully demonstrate the feasibility and convenience of developing efficient solution-processable non-doped TADF emitters based on 2 CzDMAC segment.

关 键 词：Electron-donating segment Thermally activated delayed fluorescence Solution process Non-doped emitter Organic light-emitting diode 

分 类 号：TB34[一般工业技术—材料科学与工程] TN312.8[电子电信—物理电子学]