Departments of Chemistry and Chemical Engineering , University of Massachusetts Amherst , Amherst , Massachusetts 01003 , United States.
ACS Appl Mater Interfaces. 2018 Nov 7;10(44):38574-38580. doi: 10.1021/acsami.8b12551. Epub 2018 Oct 26.
Controlling mesoscale organization in thick films of electroactive polymers is crucial for studying and optimizing charge and ion transport in these disordered materials. Conventional approaches focus on directing long-range polymer aggregation and/or crystallization during film formation by using interfaces, flow and/or shear forces. Here, we describe an alternative method that takes advantage of naturally textured biological substrates and vapor-coating to structure thick-conjugated polymer films. Reactive vapor-coating is a technique that enables in situ synthesis of doped conjugated polymers inside a reduced-pressure reactor. Reactive vapor deposition conformally coats the surface of plant matter, such as leaves and flower petals, with conducting polymer films while leaving these living substrates undamaged. Importantly, the intricate surface features of plant matter are faultlessly reproduced in the coating, effectively creating thick, high-surface-area, electrochemically active conducting polymer electrodes on plant matter. A microstructured, 10 μm thick film of p-doped poly(3,4-ethylenedioxythiophene) on a pilea involucrata leaf acts as an all-polymer pseudocapacitor with a higher areal capacitance (142 mF/cm) than an analogous film on a planar plastic substrate lacking microstructure (50 mF/cm). Taken together, reactive vapor deposition and microstructured plant matter present a unique combination of processing technique and substrate than can yield a diverse library of controllably microstructured electronic polymer films.
控制厚膜电活性聚合物的介观组织对于研究和优化这些无序材料中的电荷和离子输运至关重要。传统的方法侧重于通过使用界面、流动和/或剪切力来指导薄膜形成过程中的长程聚合物聚集和/或结晶。在这里，我们描述了一种利用天然纹理化生物衬底和气相沉积来构建厚共轭聚合物薄膜的替代方法。反应气相沉积是一种能够在减压反应器内部进行掺杂共轭聚合物原位合成的技术。反应气相沉积可将导电聚合物薄膜共形地涂覆在植物材料（如叶片和花瓣）的表面，而不会损坏这些活体衬底。重要的是，植物材料的复杂表面特征在涂层中得以完美重现，从而有效地在植物材料上形成厚的、高表面积的电化学活性导电聚合物电极。聚（3,4-亚乙基二氧噻吩）的微结构化、10 μm 厚的薄膜在 pilea involucrata 叶片上充当全聚合物赝电容器，其比缺乏微观结构的类似薄膜（50 mF/cm）的比表面积电容更高（142 mF/cm）。总之，反应气相沉积和微结构化的植物材料提供了一种独特的处理技术和衬底组合，可以产生多样化的可控微结构化电子聚合物薄膜库。
