Abstract:

In this work, a facile one-step electrodeposition method is developed to prepare 3D Ni₃S₂ interconnected nanosheet arrays on Ni foam as electrodes for suprecapacitors, resulting in excellent pseudocapacitance performance. The composition, microstructure and morphology of the prepared Ni₃S₂ materials were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy and X-ray photoelectron spectroscopy (XPS). The electrochemical capacitance properties were tested by cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) measurements in a three-electrode system. Taking advantage of the highly conductive 3D architectures, the Ni₃S₂/NF-10 electrode exhibits a superior specific capacitance of 2850 F/g at current density of 1 A/g. Remarkably, a specific capacitance of 1972 F/g could be still achieved at a high current density of 10 A/g, indicating its excellent rate capability. With the increase of the electrodeposition time, the 3D architectures of Ni₃S₂ begin to disappear, resulting in a reduced specific capacitance. The appropriate electrodeposition conditions is the key of preparation of high performance electrode materials. Test results show that the prepared Ni₃S₂ material is expected to be used in the field of electrochemical energy storage.

Key words: supercapacitor, Ni₃S₂, pseudocapacitance, electrodeposition, electrochemistry, Ni foam

摘要：

通过一步电化学沉积法在泡沫镍(Ni foam，NF)集流体上制备了3D硫化镍(Ni₃S₂)材料，利用X射线衍射仪(XRD)、扫描电子显微镜(SEM)、拉曼光谱(Raman)、X射线光电子能谱(XPS)等对所制备材料的物化结构和形貌进行了表征，并采用循环伏安法(CV)、恒流充放电法(GCD)研究了其作为超级电容器电极的电化学性能。测试结果表明，制备的Ni₃S₂/NF-10材料具有相互连接的3D结构，表现出优异的赝电容性能。在1 A/g电流密度下，比电容高达2850 F/g。将电流密度提高到10 A/g，该材料比电容仍能达到1972 F/g，说明其具有优异的倍率性能。测试结果表明所制备的Ni₃S₂材料有望应用于电化学储能领域。

关键词: 超级电容器, 硫化镍, 赝电容, 电沉积, 电化学, 泡沫镍