文献类型：期刊文献

英文题名：Theoretical investigation on reverse intersystem crossing from upper triplet to lowest singlet: A "hot exciton" path for blue fluorescent OLEDs

作者：Liu, Yidan[1,2];Yuan, Yizhong[1,2];Tian, Xiaohui[1,2];Sun, Jinyu[1,2]

机构：[1]East China Univ Sci & Technol, Key Lab Ultrafine Mat, Minist Educ, Shanghai 200237, Peoples R China;[2]East China Univ Sci & Technol, Shanghai Key Lab Adv Polymer Mat, Sch Mat Sci & Engn, Shanghai 200237, Peoples R China

年份：2020

卷号：120

期号：23

外文期刊名：INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY

收录：;EI(收录号：20203509102650);WOS:【SCI-EXPANDED(收录号:WOS:000562321700001)】；

基金：National Natural Science Foundation of China, Grant/Award Number: 21975073; Shanghai Key Laboratory Project, Grant/Award Number: 08DZ2230500; Shanghai Leading Academic Discipline Project, Grant/Award Number: B502

语种：英文

外文关键词：blue fluorescent organic light-emitting diodes; density functional theory; donor-bridge-acceptor; "hot exciton" materials

摘要：Nowadays, blue fluorescent organic light-emitting diodes (FOLEDs) have attracted considerable attention from both academia and industry. According to spin statistics, electrical excitation results in the formation of similar to 25% singlet excitons and similar to 75% triplet excitons (signifying similar to 75% energy loss), which triggered wide-ranging efforts to harvest as many triplet excitons as possible. The materials that can convert triplet excitons into singlet excitons from the high-lying excited triplet states (referred as "hot exciton" channel) to realize high efficiency were reported, which can also efficaciously avoid the accumulation of triplet excitons in T(1)state. In this study, by means of density functional theory (DFT) and time-dependent DFT, we have theoretically investigated the electronic and photophysical properties of 16 newly designed molecules with donor-bridge-acceptor framework to search for the blue FOLED materials exploiting the "hot exciton" path. Important properties, such as singlet-triplet energy gaps, absorption and emission parameters, and reverse intersystem crossing rates (k(RISC)), of five target molecules were studied. The calculated results demonstrate that thiophene-diphenylamine (k(RISC)up to 1.03 x 10(8) seconds(-1)) may have promising potential as blue FOLED materials by virtue of the "hot exciton" effect.