In this study, we report on the rational design and facile preparation of a cotton-reduced graphene oxide-silver nanoparticle (cotton-RGO-AgNP) hybrid fiber as an electrode for the building of a flexible fiber-shaped supercapacitor (FSSC). It was adequately characterized and found to possess a well-defined core−shell structure with cotton yarn as a core and a porous RGO-AgNP coating as a shell. Thanks to the unique morphological features and low electrical resistance (only 2.3 Ω·cm⁻¹), it displayed attractive supercapacitive properties. When evaluated in a three-electrode setup, this FSSC electrode delivered the highest linear and volumetric specific capacitance of up to ca. 12.09 mF·cm⁻¹ and ca. 9.67 F·cm⁻³ with a satisfactory rate capability as well as a decent cycling stability. On the other hand, an individual parallel symmetric FSSC cell constructed by this composite fiber fulfilled the largest linear and volumetric specific capacitance of ca. 1.67 mF·cm⁻¹ and ca. 0.67 F·cm⁻³ and offered the maximum energy density, as high as ca. 93.1 μWh·cm⁻³, which outperformed a great number of graphene- and textile yarn-based FSSCs. Impressively, bending deformation brought about quite a limited effect on its electrochemical behaviors and almost no capacitance degradation took place during the consecutive charge/discharge test for over 10,000 cycles. Consequently, these remarkable performances suggest that the currently developed cotton-RGO-AgNP fiber has considerable application potential in flexible, portable and wearable electronics.

中文翻译：

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商用棉纱作为电极构建柔性纤维状超级电容器的表面改性

在这项研究中，我们报告了棉花还原氧化石墨烯-银纳米颗粒（棉花-RGO-AgNP）混合纤维作为构建柔性纤维状超级电容器（FSSC）的电极的合理设计和简便制备。它被充分表征并发现具有明确定义的核壳结构，以棉纱为核，以多孔 RGO-AgNP 涂层为壳。由于独特的形态特征和低电阻（仅 2.3 Ω·cm ^-1），它显示出极具吸引力的超级电容特性。在三电极设置中进行评估时，该 FSSC 电极提供了最高的线性和体积比电容，高达约 12.09 mF·cm ^-1和约。9.67 F·cm ^-3具有令人满意的倍率性能和良好的循环稳定性。另一方面，由这种复合纤维构建的单个平行对称 FSSC 电池实现了约 10 的最大线性和体积比电容。1.67 mF·cm ^-1和约。0.67 F·cm ^-3并提供最大能量密度，高达约。93.1 μWh·cm ^-3，其性能优于大量基于石墨烯和纺织纱线的 FSSC。令人印象深刻的是，弯曲变形对其电化学行为的影响非常有限，并且在连续充电/放电测试超过 10,000 次循环期间几乎没有发生电容退化。因此，这些卓越的性能表明目前开发的棉-RGO-AgNP 纤维在柔性、便携式和可穿戴电子产品中具有相当大的应用潜力。