Isomerization effect of triphenylamine-acridine derivatives on excited-state modification, photophysical property and electroluminescence performance
作者:Changjiang Zhou、Tingke Zhang、Shitong Zhang、Haichao Liu、Yu Gao、Qing Su、Qiaolin Wu、Weijun Li、Jiangshan Chen、Bing Yang
DOI:10.1016/j.dyepig.2017.07.056
日期:2017.11
emissive state character. The four isomers exhibit gradually increased PL efficiency from low-polarity hexane to medium-polarity tetrahydrofuran (THF), which could be assigned to the formation of hybridized local and charge-transfer (HLCT) states and effectively suppressed non-radiative transition arised from acridine in medium-polarity solvents. Among four isomers, TPA-3AC achieved the best EL performance
电荷转移(CT)状态正成为一种有用的激发态,可用于设计用于高性能有机发光二极管(OLED)的下一代发光材料。但是,由于HOMO和LUMO之间的重叠很小,强CT状态通常会导致光致发光(PL)效率严重下降。为了在荧光OLED中同时获得高激子利用率和高PL效率,通过结构调制找出在激发态下CT组件的精细修饰策略非常重要。在这项工作中,设计并合成了四种供体-受体结构的三苯胺(TPA)-cr啶(AC)异构体(TPA-9AC,TPA-1AC,TPA-2AC和TPA-3AC),以研究异构化效果与激发态性质。进行密度泛函理论(DFT)计算以及溶剂变色吸收,发射和光致发光衰减光谱,以深入了解其发射态特征。四种异构体的PL效率从低极性己烷到中极性四氢呋喃(THF)逐渐增加,这可以归因于形成混合的局部和电荷转移(HLCT)状态,并有效抑制了cr啶引起的非辐射跃迁在中极性溶剂中。在四种异构体中,由于适当的LE和CT