School of Chemical Engineering, Chonbuk National University , 567 Baekje-daero, Deokjin-gu, Jeonju-si, Jeollabuk-do 54896, Republic of Korea.
Department of Chemical & Biomolecular Engineering, Seoul National University of Science and Technology , 232 Gongneung-ro, Nowon-gu, Seoul 139-743, Republic of Korea.
ACS Appl Mater Interfaces. 2017 Jun 14;9(23):19925-19933. doi: 10.1021/acsami.7b04753. Epub 2017 Jun 2.
Fiber electrodes provide interesting opportunities for energy storage by providing both mechanical flexibility and the opportunity to impart multifunctionality to fabrics. We show here carbon nanotube (CNT)-embedded agarose gel composite fiber electrodes, with a diameter of ∼120 μm, consisting of 60 wt % CNTs that can serve as the basis for flexible and wearable fiber microsupercapacitors (mSCs). Via an extrusion process, CNT bundles are induced to align in an agarose filament matrix. Due to the shear alignment of the CNT bundles, the dehydrated filaments have an electrical conductivity as high as 8.3 S cm. The composite fiber electrodes are mechanically stable, enabling formation of twisted two-ply fiber mSCs integrated with a solid electrolyte. The fiber mSC shows a high capacitance (∼1.2 F cm), good rate retention (∼90%) at discharge current densities ranging from 5.1 to 38 mA cm, long cycle life under repeated charging/discharging (10% fade after 10 000 cycles) and good performance after at least 1000 cycles of deformation, with a radius of curvature of 12.3 mm (90° bend). After being coated with a thin layer of poly(dimethylsiloxane), the fiber mSCs could be cycled over 10 000 times under water. Impedance studies indicate that the superior performance is due to the high electrical conductivity along the aligned CNTs and the large electrode surface area that is accessible through the ion-conducting agarose.
纤维电极通过提供机械柔韧性和为织物赋予多功能性，为储能提供了有趣的机会。我们在此展示了一种直径约为 120μm 的碳纳米管（CNT）嵌入琼脂糖凝胶复合纤维电极，其中包含 60wt%的 CNT，可以作为柔性和可穿戴纤维微超级电容器（mSCs）的基础。通过挤压工艺，将 CNT 束诱导排列在琼脂糖长丝基体中。由于 CNT 束的剪切排列，脱水纤维的电导率高达 8.3 S cm。复合纤维电极具有机械稳定性，能够形成与固体电解质集成的扭曲双层纤维 mSCs。纤维 mSC 具有较高的电容（约 1.2 F cm），在 5.1 至 38 mA cm 的放电电流密度范围内具有良好的倍率保持率（约 90%），在反复充电/放电下具有长循环寿命（10000 次循环后衰减 10%），在至少 1000 次变形循环后性能良好，曲率半径为 12.3mm（90°弯曲）。在涂覆一层薄薄的聚二甲基硅氧烷后，纤维 mSCs 可以在水下循环 10000 多次。阻抗研究表明，优异的性能归因于沿对齐 CNT 具有高导电性和通过离子传导琼脂糖可获得的大电极表面积。
