Abstract Spinel sulfide NiCo2S4 (NCS) is one of the ternary metal sulfides, used as a promising electrode for hybrid capacitor, which is beneficial from its multi-active sites and good conductivity. In this study, NCS with sulfur vacancies was obtained through a one-step hydrothermal reaction. The morphology of NCS was regulated by adding a certain content of urea. Additionally, flower-like NCS was obtained when 10 mmol of urea was added, whose highest specific capacity performance was 453.40 C g−1 at 1 A g−1. Meanwhile, the as-prepared NCS electrode and activated carbon electrode were fabricated into hybrid capacitors. The energy density of such a device reached the highest value of 27.77 Wh kg−1, whereas the maximum power density was 13.34 kW kg−1. Moreover, this hybrid capacitor maintained the 62.07% of its initial capacity after 10 000 cycles at 2 A g−1, indicating that this one-step synthesized NCS has potential to be applied to long-serving energy storage device.

中文翻译：

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用于混合电容器的具有高电化学性能的 NiCo2S4 的一步合成

摘要 尖晶石硫化物NiCo2S4（NCS）是三元金属硫化物之一，具有多活性位点和良好的导电性，是一种很有前景的混合电容器电极。在这项研究中，通过一步水热反应获得了具有硫空位的 NCS。NCS的形态是通过添加一定含量的尿素来调节的。此外，当加入 10 mmol 尿素时获得花状 NCS，其最高比容量性能为 453.40 C g-1，1 A g-1。同时，将所制备的 NCS 电极和活性炭电极制成混合电容器。这种器件的能量密度达到最高值 27.77 Wh kg-1，而最大功率密度为 13.34 kW kg-1。此外，该混合电容器保持了 62。