Luo Xuyi, Shen Hongguang, Perera Kuluni, Tran Dung Trong, Boudouris Bryan W, Mei Jianguo
Department of Chemistry, Purdue University, West Lafayette, Indiana 47907, United States.
Charles D. Davidson School of Chemical Engineering, Purdue University, West Lafayette, Indiana 47907, United States.
ACS Macro Lett. 2021 Aug 17;10(8):1061-1067. doi: 10.1021/acsmacrolett.1c00328. Epub 2021 Jul 30.
Organic electrochemical transistors (OECTs) are oft-used for bioelectronic applications, and a variety of OECT channel materials have been developed in recent years. However, the majority of these materials are still limited by long-term performance and stability challenges. To resolve these issues, we implemented a next-generation design of polymers for OECTs. Specifically, diketopyrrolopyrrole (DPP) building blocks were copolymerized with propylene dioxythiophene-based (Pro-based) monomers to create a donor-acceptor-type conjugated polymer (PProDOT-DPP). These PProDOT-DPP macromolecules were synthesized using a straightforward direct arylation polymerization synthetic route. The PProDOT-DPP polymer thin film exhibited excellent electrochemical response, low oxidation potential, and high crystallinity, as evidenced by spectroelectrochemical measurements and grazing incidence wide-angle X-ray scattering measurements. Thus, the resultant polymer thin films had high charge mobility and volumetric capacitance values (i.e., μ* as high as 310 F cm V s) when they were used as the active layer materials in OECT devices, which places PProDOT-DPP among the highest performing accumulation-mode OECT polymers reported to date. The performance of the PProDOT-DPP thin films was also retained for 100 cycles and over 2000 s of ON-OFF cycling, indicating the robust stability of the materials. Therefore, this effort provides a clear roadmap for the design of electrochemically active macromolecules for accumulation-mode OECTs, where crystalline acceptor cores are incorporated into an all-donor polymer. We anticipate that this will ultimately inspire future polymer designs to enable OECTs with both high electrical performance and operational stability.
有机电化学晶体管（OECTs）常用于生物电子应用，近年来已开发出多种OECT沟道材料。然而，这些材料中的大多数仍受到长期性能和稳定性挑战的限制。为了解决这些问题，我们实施了一种用于OECTs的下一代聚合物设计。具体来说，将二酮吡咯并吡咯（DPP）结构单元与基于丙二氧基噻吩（Pro基）的单体共聚，以制备供体-受体型共轭聚合物（PProDOT-DPP）。这些PProDOT-DPP大分子是通过直接芳基化聚合的合成路线直接合成的。光谱电化学测量和掠入射广角X射线散射测量表明，PProDOT-DPP聚合物薄膜表现出优异的电化学响应、低氧化电位和高结晶度。因此，当这些聚合物薄膜用作OECT器件的有源层材料时，具有高电荷迁移率和体积电容值（即μ*高达310 F cm V s），这使PProDOT-DPP跻身于迄今为止报道的性能最高的累积模式OECT聚合物之列。PProDOT-DPP薄膜的性能在100个循环和超过2000秒的开-关循环中也得以保持，表明材料具有强大的稳定性。因此，这项工作为设计用于累积模式OECTs的电化学活性大分子提供了明确的路线图，即将结晶受体核引入全供体聚合物中。我们预计，这最终将激发未来的聚合物设计，以实现具有高电性能和操作稳定性的OECTs。
