Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Department of Materials Science and Engineering, University of Illinois at Urbana-Champaign, 104 South Goodwin Avenue, Urbana Illinois 61801, USA.
Nat Commun. 2017 Jul 13;8:16070. doi: 10.1038/ncomms16070.
Solution processable semiconducting polymers have been under intense investigations due to their diverse applications from printed electronics to biomedical devices. However, controlling the macromolecular assembly across length scales during solution coating remains a key challenge, largely due to the disparity in timescales of polymer assembly and high-throughput printing/coating. Herein we propose the concept of dynamic templating to expedite polymer nucleation and the ensuing assembly process, inspired by biomineralization templates capable of surface reconfiguration. Molecular dynamic simulations reveal that surface reconfigurability is key to promoting template-polymer interactions, thereby lowering polymer nucleation barrier. Employing ionic-liquid-based dynamic template during meniscus-guided coating results in highly aligned, highly crystalline donor-acceptor polymer thin films over large area (>1 cm) and promoted charge transport along both the polymer backbone and the π-π stacking direction in field-effect transistors. We further demonstrate that the charge transport anisotropy can be reversed by tuning the degree of polymer backbone alignment.
由于在从印刷电子学到生物医学设备的各种应用中具有多样性，因此溶液处理的半导体聚合物一直受到强烈关注。然而，在溶液涂层过程中控制大分子的长程组装仍然是一个关键挑战，这主要是由于聚合物组装的时间尺度和高通量打印/涂层之间的差异。受能够进行表面重配置的生物矿化模板的启发，我们提出了动态模板的概念，以加速聚合物成核和后续的组装过程。分子动力学模拟表明，表面可重构性是促进模板-聚合物相互作用的关键，从而降低了聚合物成核势垒。在界面引导涂层过程中使用基于离子液体的动态模板，可在大面积（>1cm）上获得高度取向和结晶的给体-受体聚合物薄膜，并在晶体管中促进聚合物主链和π-π堆积方向上的电荷输运。我们进一步证明，通过调整聚合物主链取向度，可以反转电荷输运各向异性。
