Abstract Nano-structured Ni3S2 is regarded as one of the most promising supercapacitor (SC) electrode materials due to its unique heazlewoodite phase and high electronic conductivity. However, preparation of Ni3S2 nanostructures with controllable chemical stoichiometry and morphology is still a challenge issue. Herein, we report a novel Ni3S2/3D graphene/nickel foam (Ni3S2/3D G/NF) composite electrode prepared by a chemical vapor deposition (CVD) followed by an electrodeposition. The as-prepared Ni3S2/3D G/NF composite electrode is stable with good chemical stoichiometry, binder-free and exhibits an excellent specific capacitance up to 2585 F/g with current density of 1 A/g,a high capacitance retention rate ~70.68% as the current density increases to 30 A/g, and a capacitance remaining ~88.9% after 5000 cycles of charge and discharge with the current density of 20 A/g. The perfect Ni3S2 heazlewoodite phase and good contact between Ni3S2 and the surface of 3D G/NF are believed to be responsible for the greatly improved conductivity and specific surface area of the as-prepare composite electrode. Our result has provided an effective way to significantly improve the capacitive property of Ni3S2 and shown a great potential for realizing its practical SC applications.

中文翻译：

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用于超级电容器应用的高性能 Ni3S2/3D 石墨烯/泡沫镍复合电极

摘要 纳米结构的Ni3S2由于其独特的heazlewoodite相和高电子电导率被认为是最有前途的超级电容器(SC)电极材料之一。然而，制备具有可控化学计量和形态的 Ni3S2 纳米结构仍然是一个具有挑战性的问题。在此，我们报告了一种通过化学气相沉积 (CVD) 和电沉积制备的新型 Ni3S2/3D 石墨烯/泡沫镍 (Ni3S2/3D G/NF) 复合电极。所制备的 Ni3S2/3D G/NF 复合电极稳定，具有良好的化学计量比，不含粘合剂，在电流密度为 1 A/g 的情况下表现出高达 2585 F/g 的优异比电容，高电容保持率~70.68 % 随着电流密度增加到 30 A/g，并且电容保持 ~88。以20 A/g的电流密度充放电5000次循环后为9%。完美的 Ni3S2 heazlewoodite 相和 Ni3S2 与 3D G/NF 表面之间的良好接触被认为是导致所制备复合电极的电导率和比表面积大大提高的原因。我们的结果为显着提高 Ni3S2 的电容性能提供了一种有效的方法，并显示出实现其实际 SC 应用的巨大潜力。