烷基链长度对非对称含噻吩五元稠环化合物传输性能的影响  

Influence of Alkyl Chain Length on the Transport Properties of Asymmetric Five-ring-fused Thienoacenes

作　　者：李骅峰 李伟利 田洪坤[1,2] 王利祥 LI Hua-Feng;LI Wei-Li;TIAN Hong-Kun;WANG Li-Xiang(State Key Laboratory of Polymer Physics and Chemistry,Changchun Institute of Applied Chemistry,Chinese Academy of Sciences,Changchun 130022,China;University of Science and Technology of China,Hefei 230026,China)

机构地区：[1]中国科学院长春应用化学研究所,高分子物理与化学国家重点实验室,长春130022 [2]中国科学技术大学,合肥230026

出　　处：《应用化学》2023年第7期1054-1060,共7页Chinese Journal of Applied Chemistry

基　　金：国家自然科学基金(Nos.22075273,51273192)资助。

摘　　要：含噻吩并苯类分子是一类代表性的高迁移率有机半导体材料,以其为共轭骨架构建的不对称分子在薄膜中倾向于形成双层排列结构,并以二维层状方式生长,有利于实现高迁移率。烷基取代基的长度会对有机半导体材料的堆积形貌产生影响。本文设计合成了不同长度烷基链取代的噻吩并[4,5-b][1]苯并噻吩并[3,2-b][1]苯并噻吩(syn-BTBTT-Cn,n=4,5,6,7,8,10),系统研究了烷基链长度对化合物热稳定性、能级、载流子传输能力、堆积结构和薄膜形貌等方面的影响。结果表明,所有化合物均不具备液晶性,热稳定性良好。在所制备的蒸镀薄膜中所有分子均形成双层堆积结构,共轭核在层内形成鱼骨架堆积,烷基链长度会影响薄膜的有序度和堆积的紧密程度。基于该类材料制备的有机薄膜晶体管(OTFT)器件的迁移率都超过7.0 cm^(2)/(V·s),其中syn-BTBTT-C8分子的迁移率最高可达13.8 cm^(2)/(V·s),平均值为12.5 cm^(2)/(V·s)。Thienoacenes are a representative class of high mobility organic semiconductor materials(OSCs).Asymmetric molecules based on them tend to form a bilayer arrangement in thin films and grow in a twodimensional layer-like manner,which has the advantage of achieving high mobility.The length of the alkyl substituents affects the packing microstructure of OSCs.Herein,thieno[4,5-b][1]benzothieno[3,2-b][1]benzothiophenes substituted with different lengths of alkyl chains(syn-BTBTT-Cn,n=4,5,6,7,8,10) are designed and synthesized to systematically investigate the effects of lengths of alkyl chains on their thermal stability,energy levels,charge carrier transport capabilities,packing structures and film morphologies.All compounds are thermally stable and do not have liquid crystalline behaviors.All molecules in the vacuumdeposited films form a bilayer arrangement,within the conjugated cores forming a herringbone packing motif,and the alkyl chain length affects the film order and the tightness of the packing.Organic thin.film transistors devices all exhibit mobilities beyond 7.0 cm~2/(V·s).Among them,the syn-BTBTT-C8 devices show a mobility of up to 13.8 cm~2/(V·s) with the average values of 12.5 cm~2/(V·s).

关 键 词：含噻吩并苯类分子 非对称结构 有机薄膜晶体管 迁移率 

分 类 号：O649[理学—物理化学]