基于TPA-DPP骨架的新型D-A-D'有机小分子给体的设计与性能  

Design and properties of novel D-A-D'organic small molecule donors based on TPA-DPP skeleton

作　　者：王雅洁 李艳芹 殷伦祥 WANG Ya-jie;LI Yan-qin;YIN Lun-xiang(School of Chemical Engineering,Dalian University of Technology,Dalian 116024,China)

机构地区：[1]大连理工大学化工学院,辽宁大连116024

出　　处：《分子科学学报》2023年第2期146-153,共8页Journal of Molecular Science

基　　金：国家自然科学基金资助项目(21102013);高校基本科研业务重大项目专项(DUT16AD205)。

摘　　要：以三苯胺(TPA)-吡咯并吡咯二酮(DPP)为骨架,分别以咔唑(CZ)和芴(FLU)为端基合成了2种新型D-A-D′型小分子给体材料TPADPPCZ和TPADPPFLU,通过紫外-可见吸收光谱和循环伏安法研究了它们的光学和电化学性质.TPADPPCZ和TPADPPFLU均获得了较窄的带隙(1.66和1.81eV),与TPADPPCZ相比,TPADPPFLU的HOMO能级更低(分别为-5.13和-5.26eV).此外,以富勒烯PC_(71)BM为受体,TPADPPCZ和TPADPPFLU为给体制备了本体异质结有机光伏器件.基于TPADPPFLU材料制备的器件获得了更高的开路电压0.88 V,同时得到了3.54%的光电转换效率.结果表明在D-A-D′不对称结构中引入弱给电子端基(D′)可以有效降低材料的HOMO能级,提升开路电压,最终实现调控光伏性能的目的.As a new type of solar cells,organic solar cells(OSCs)have been widely investigated because of its outstan-ding advantages such as light weight,flexibility and well-defined structure and it shows great application prospects towards commercialization of small electrical appliances.In recent years,asymmetricπ-conjugation small molecule delivers exce-llent optoelectronic properties compared with symmetric counterpart,on one hand,asymmetric organic semiconductors possess flexible intramolecular charge transfer(ICT)from donor(D)block to acceptor(A)block.On the other hand,they tend to provide large dipole moment of the molecule favored intermolecular interaction force,and thus enhanceπ-πinteractions of the molecule.However,there are fewer investigations were reported aiming to the D-A-D′type molecule among different types of push-pull conjugation(D-A,D-A-D′,D-A-A′).Herein,we choose D-A-D′template in conjugation with carbazole and fluorene as end group.The research shows that fluorene unit has the following advantages:(1)weake electron donating ability and deep HOMO energy level,which is helpful for higher open circuit voltage;(2)the modification of alkyl chain attached fluorene can improve solubility of material and modify nanoscale film morphology of the device;(3)low ionization potential tend to focus on building optimal nanoscale network in the device.For comparison of photovoltaic properties of the devices,a carbazole unit with strong electron-donating ability was introduced as the end group.In addition,the propeller-structured triphenylamine was used as electron-donating unit to promote electron donating ability of the molecule.At the same time,diketopyrrolopyrrole(DPP)unit was introduced to broaden the light absorption range of the material.In summary,TPA-DPP was used as the skeleton,carbazole and fluorene were employed as electron-donating units,respectively,and ethynyl group was inserted between carbazole/fluorene moiety and TPA-DPP framework asπspacer to reduce the internal torsion angle of the mol

关 键 词：有机小分子给体 三苯胺 吡咯并吡咯二酮 咔唑 芴 

分 类 号：O622[理学—有机化学]