Supercapacitors do not only exhibit the traditional high power density of capacitors, but also show the high energy density characteristic for batteries. In addition, fast charging, outstanding rate of magnification, and safety as well as pollutant‐free characteristics make supercapacitors unprecedented for applications and development prospects in the field of energy storage. In this study, a facile two‐step hydrothermal method was presented for the synthesis of FeCo₂S₄ nanowire structures directly formed on nickel (Ni) foam. The as‐prepared FeCo₂S₄ samples were characterized using X‐ray powder diffraction and scanning electron microscopy. The electrochemical performance of the as‐prepared FeCo₂S₄ electrodes is studied by cyclic voltammetry (CV), galvanostatic charge‐discharge measurements (CD), and cycle stability tests. The as‐prepared FeCo₂S₄ nanowires exhibit a high specific capacitance of about 337 mAh g⁻¹ at a current density of 2 A g⁻¹ in 3 M KOH solution. After 2000 cycles at 6 A g⁻¹, 90 % of the initial capacity is retained, showing the excellent stability of the prepared material. At a high current density of 12 A g⁻¹, the capacity can reach 273 mAh g⁻¹ with 81 % remaining, exhibiting outstanding rate characteristics. The superior electrochemical performance can be attributed to the high specific surface area, ion/electron transportability, and the excellent electrical conductivity of the active material itself. Therefore, as the most advanced energy storage material, FeCo₂S₄ will have great development prospects in terms of energy conversion, storage, and electrocatalysis.

中文翻译：

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镍泡沫上的铁钴双金属硫化物纳米线，用于高性能超级电容器

超级电容器不仅展现出电容器的传统高功率密度，而且展现出电池的高能量密度特性。此外，快速充电，出色的放大倍率，安全性和无污染特性使超级电容器在储能领域的应用和发展前景前所未有。在这项研究中，提出了一种简便的两步水热法来合成直接在镍（Ni）泡沫上形成的FeCo ₂ S ₄纳米线结构。使用X射线粉末衍射和扫描电子显微镜对所制备的FeCo ₂ S ₄样品进行表征。制备的FeCo ₂ S的电化学性能通过循环伏安法（CV），恒电流充放电测量（CD）和循环稳定性测试研究了_4个电极。所制备的FeCo ₂ S ₄纳米线在3 M KOH溶液中的电流密度为2 A g ^-1时，显示出约337 mAh g ^-1的高比电容。在6 A g ^-1下进行2000次循环后，保留了90％的初始容量，显示了所制备材料的出色稳定性。在12 A g ^-1的高电流密度下，容量可以达到273 mAh g ^-1剩余的81％，具有出色的速率特性。优异的电化学性能可归因于活性材料本身的高比表面积，离子/电子传输性和优异的导电性。因此，FeCo ₂ S ₄作为最先进的储能材料，在能量转化，储能和电催化方面将具有广阔的发展前景。