Kothavale Shantaram, Lee Kyung Hyung, Lee Jun Yeob
School of Chemical Engineering , Sungkyunkwan University , 2066, Seobu-ro , Jangan-gu, Suwon , Gyeonggi 440-746 , Korea.
ACS Appl Mater Interfaces. 2019 May 15;11(19):17583-17591. doi: 10.1021/acsami.9b02824. Epub 2019 Apr 30.
Highly efficient yellow and red thermally activated delayed fluorescent (TADF) organic light-emitting diodes were developed using two quinoxalinedicarbonitrile units, quinoxaline-6,7-dicarbonitrile (6,7-DCQx) and quinoxaline-5,8-dicarbonitrile (5,8-DCQx) as electron acceptors, and t-butylcarbazole or 9,9-dimethylacridan as electron donors. The strong electron-withdrawing capability of the 5,8-DCQx and 6,7-DCQx acceptors enabled from yellow to red emission in the TADF emitters. Comparing 5,8-DCQx and 6,7-DCQx, a red-shifted emission by about 40 nm was observed in the 5,8-DCQx acceptor-based emitters, but the external quantum efficiency of the TADF devices was over 20% irrespective of the acceptor, proving the usefulness of the two acceptor moieties as the building blocks of the TADF emitters. Therefore, the quinoxalinedicarbonitrile acceptors are promising as the acceptor moiety for designing yellow or red TADF emitters.
使用两个喹喔啉二腈单元，即喹喔啉-6,7-二腈（6,7-DCQx）和喹喔啉-5,8-二腈（5,8-DCQx）作为电子受体，以及叔丁基咔唑或9,9-二甲基吖啶作为电子供体，开发出了高效的黄色和红色热激活延迟荧光（TADF）有机发光二极管。5,8-DCQx和6,7-DCQx受体的强吸电子能力使得TADF发射体能够实现从黄色到红色的发射。比较5,8-DCQx和6,7-DCQx，在基于5,8-DCQx受体的发射体中观察到发射峰红移了约40 nm，但无论使用哪种受体，TADF器件的外量子效率均超过20%，这证明了这两种受体部分作为TADF发射体构建单元的有效性。因此，喹喔啉二腈受体有望作为设计黄色或红色TADF发射体的受体部分。
