基于螺芴基团的红光热激活延迟荧光材料  

Red Light Thermally Activated Delayed Fluorescence Materials Based on Spirofluorene Units

作　　者：高珊[1] 巩世烜 靳雨鑫 陈子奇 马金珠 冯敏强[1] 樊健[1] GAO Shan;GONG Shixuan;JIN Yuxin;CHEN Ziqi;MA Jinzhu;FUNG ManKeung;FAN Jian(Jiangsu Key Laboratory for Carbon-Based Functional Materials&Devices,Institute of Functional Nano&Soft Materials,Soochow University,Suzhou 215123,China)

机构地区：[1]苏州大学功能纳米与软物质研究院,江苏省碳基功能材料与器件重点实验室,苏州215123

出　　处：《高等学校化学学报》2025年第5期75-83,共9页Chemical Journal of Chinese Universities

基　　金：国家重点研究发展计划项目(批准号:2020YFA0714604);国家自然科学基金(批准号:22005184);江苏省国际科技合作/港澳台科技合作项目(批准号:BZ2023053)资助.

摘　　要：在常用的三苯胺给体单元和二苯并[a,c]吩嗪受体单元的基础上,利用螺芴基团的空间位阻效应,设计并合成了TPA-DSP和SPTPA-DSP两种红光热激活延迟荧光(TADF)材料.螺芴基团凭借自身较大的空间位阻增加了分子的刚性,避免了发光核心基团的紧密堆积,减少了非辐射跃迁能量损失,有利于提升器件性能.在掺杂到4,4′-二(9-咔唑)联苯(CBP)中作为有机发光层时,TPA-DSP和SPTPA-DSP在有机电致发光器件(OLED)中表现出优异的性能.TPA-DSP和SPTPA-DSP均发射红光,TPA-DSP在7%(质量分数)掺杂浓度下在580 nm处实现了17.8%的最大外量子效率(EQE),SPTPA-DSP在7%(质量分数)掺杂浓度下在580 nm处实现了19.3%的最大EQE.TPA-DSP和SPTPA-DSP的最大亮度分别达到了11800和12650 cd/m^(2),最大电流效率(CE)均达到了40.0 cd/A,最大功率效率(PE)分别达到了44.3和47.2 lm/W.由于具有更大的空间位阻,多螺芴基团的SPTPADSP展现出更加优异的器件性能.该研究表明,螺芴基团通过空间位阻的多重作用能够有效提高热激活延迟荧光材料的性能,可进一步利用与开发.On the basis of commonly used triphenylamine donor units and dibenzo[a,c]phenazine acceptor units,two red light thermally activated delayed fluorescence(TADF)materials TPA-DSP and SPTPA-DSP were designed and synthesized by the steric hindrance effect of spirofluorene group.The spirofluorene group,known for its large steric hindrance,increases the rigidity of the molecule,avoids tight packing between emissive cores and effectively reduces non-radiative transition energy loss,which is crucial for improving device performance.When doping in 4,4′-bis(N-carbazolyl)-1,1′-biphenyl(CBP)as organic light emitting layer,TPA-DSP and SPTPA-DSP exhibited excellent performance in organic light-emitting diodes(OLEDs).Both materials emitted red light,with TPA-DSP achieving a maximum external quantum efficiency(EQE)of 17.8%at 580 nm with a 7%doping concentration(mass fraction).SPTPA-DSP,featuring multiple spirofluorene groups,demonstrated superior device performance,achieving a maximum EQE of 19.3%at 580 nm with a 7%doping concentration(mass fraction).The maximum luminance of TPA-DSP and SPTPA-DSP reached 11800 and 12650 cd/m^(2),the maximum current efficiency(CE)both reached 40.0 cd/A,and the maximum power efficiency(PE)reached 44.3 and 47.2 lm/W,respectively.Notably,SPTPA-DSP,featuring multiple spirofluorene groups,demonstrated superior device performance due to its greater steric hindrance.Our findings underscore the potential of the spirofluorene group to enhance the performance of TADF materials through steric hindrance effects,which not only contributes to understanding the effect of steric hindrance in TADF but also paves the way for further advancements and applications.

关 键 词：热激活延迟荧光 红光 空间位阻 螺芴 

分 类 号：O621.22[理学—有机化学]