Abstract ZnFe2O4 (ZFO) has attracted considerable attention for supercapacitors (SCs), but its performances are severely hindered by intrinsically low electronic conductivity, relatively low mechanical stability, and severe agglomeration during the charge-discharge process. Here, a novel cotton derived active carbon fiber (ACF) with hierarchical porous architecture is used as template/scaffold, ZnFe2O4 nanoparticles/active carbon fiber composites (ZFO-ACFs) are prepared, in which ZFO nanoparticles (∼20 nm) are confined into the larger nanopores (∼20 nm) of the cotton derived active carbon fiber (ACF) while the smaller nanopores (∼2.5 nm) still are preserved. The cotton derived ACF matrix not only controls the size of ZFO particles and avoids self-aggregation but also offers continuous electron pathway and rapid ion transport channel, and prevents the loss of active material (ZFO) during the electrochemical reaction. The ZFO-ACFs electrode exhibits high specific capacitance of 192 F g−1 (58.7 mAh g−1). Moreover, enhanced rate capability are also obtained.

中文翻译：

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用于高倍率超级电容器电极的ZnFe 2 O 4 纳米颗粒-棉花衍生的分级多孔活性炭纤维

摘要 ZnFe2O4（ZFO）作为超级电容器（SCs）引起了广泛关注，但其固有的低电子电导率、相对较低的机械稳定性和充放电过程中严重的团聚严重阻碍了其性能。在这里，一种具有分级多孔结构的新型棉衍生活性炭纤维（ACF）用作模板/支架，制备了 ZnFe2O4 纳米颗粒/活性炭纤维复合材料（ZFO-ACF），其中 ZFO 纳米颗粒（~20 nm）被限制在棉衍生活性炭纤维 (ACF) 的较大纳米孔 (~20 nm) 而较小的纳米孔 (~2.5 nm) 仍然保留。棉花衍生的 ACF 基质不仅控制 ZFO 颗粒的大小，避免自聚集，而且提供连续的电子通路和快速的离子传输通道，并防止电化学反应过程中活性材料 (ZFO) 的损失。ZFO-ACFs 电极表现出 192 F g-1 (58.7 mAh g-1) 的高比电容。此外，还获得了增强的速率能力。