Xu Jie, Wu Hung-Chin, Mun Jaewan, Ning Rui, Wang Weichen, Wang Ging-Ji Nathan, Nikzad Shayla, Yan Hongping, Gu Xiaodan, Luo Shaochuan, Zhou Dongshan, Tok Jeffrey B-H, Bao Zhenan
Department of Chemical Engineering, Stanford University, Stanford, CA, 94305, USA.
Nanoscience and Technology Division, Argonne National Laboratory, 9700 South Cass Avenue, Lemont, IL, 60439, USA.
Adv Mater. 2022 Jun;34(22):e2104747. doi: 10.1002/adma.202104747. Epub 2021 Sep 24.
In order to apply polymer semiconductors to stretchable electronics, they need to be easily deformed under strain without being damaged. A small number of conjugated polymers, typically with semicrystalline packing structures, have been reported to exhibit mechanical stretchability. Herein, a method is reported to modify polymer semiconductor packing-structure using a molecular additive, dioctyl phthalate (DOP), which is found to act as a molecular spacer, to be inserted between the amorphous chain networks and disrupt the crystalline packing. As a result, large-crystal growth is suppressed while short-range aggregations of conjugated polymers are promoted, which leads to an improved mechanical stretchability without affecting charge-carrier transport. Due to the reduced conjugated polymer intermolecular interactions, strain-induced chain alignment and crystallization are observed. By adding DOP to a well-known conjugated polymer, poly[2,5-bis(4-decyltetradecyl)pyrrolo[3,4-c]pyrrole-1,4-(2H,5H)-dione-(E)-1,2-di(2,2'-bithiophen-5-yl)ethene] (DPPTVT), stretchable transistors are obtained with anisotropic charge-carrier mobilities under strain, and stable current output under strain up to 100%.
为了将聚合物半导体应用于可拉伸电子器件，它们需要在应变下易于变形而不被损坏。据报道，少数具有半结晶堆积结构的共轭聚合物表现出机械拉伸性。在此，报道了一种使用分子添加剂邻苯二甲酸二辛酯（DOP）来修饰聚合物半导体堆积结构的方法，发现该添加剂可作为分子间隔物插入无定形链网络之间并破坏晶体堆积。结果，大晶体生长受到抑制，同时共轭聚合物的短程聚集得到促进，这导致机械拉伸性得到改善而不影响电荷载流子传输。由于共轭聚合物分子间相互作用的减少，观察到应变诱导的链排列和结晶。通过将DOP添加到一种著名的共轭聚合物聚[2,5-双（4-癸基十四烷基）吡咯并[3,4-c]吡咯-1,4-（2H,5H）-二酮-（E）-1,2-二（2,2'-联噻吩-5-基）乙烯]（DPPTVT）中，获得了在应变下具有各向异性电荷载流子迁移率且在高达100%的应变下具有稳定电流输出的可拉伸晶体管。
