Department of Physics, Beihang University , Beijing 100191, P. R. China.
Beijing Key Laboratory for Magneto-Photoelectrical Composite and Interface Science, School of Mathematics and Physics, University of Science and Technology Beijing , Beijing 100083, P. R. China.
ACS Appl Mater Interfaces. 2017 Jun 7;9(22):18774-18781. doi: 10.1021/acsami.7b03254. Epub 2017 May 22.
Ternary cobalt nickel sulfide as a novel and efficient electrode material in supercapacitors has recently gained extensive interests. Herein, we first report a highly conductive caterpillar-like NiCoS, composed of NiCoS nanosheet core and nanowire shell grown on Ni foam via a facile and cost-effective chemical liquid process. Growth mechanism of the NiCoS nanosheets@nanowires (NSNWs) structure was also investigated in detail by analyzing time-dependent experimental as well as the amount of additive ammonium fluoride in solution. Furthermore, the electrochemical measurements were performed among three different morphologies of NiCoS including nanosheets, nanosheets@nanoparticles, and NSNWs structure, which were obtained from different reaction stages. Because the NSNWs structure has relatively high electroactive surface area, conductivity, and effective electron transport pathways, the as-prepared NiCoS NSNWs structure comparing with two other morphologies exhibits the maximum specific capacity of 1777 F/g at 1 A/g and the highest capacitance retention (83% after 3000 cycles) at a high scan rate of 10 A/g with a mass loading density of 4.0 mg/cm. These results indicate that the NiCoS NSNWs structure has great potential in supercapacitors.
三元钴镍硫化物作为一种新型高效的超级电容器电极材料，近年来引起了广泛的关注。本文首次报道了一种高导电性的毛毛虫状 NiCoS，它由 Ni 泡沫上通过简便、经济的化学液相法生长的 NiCoS 纳米片核和纳米线壳组成。通过分析随时间变化的实验以及溶液中添加的氟化铵的量，详细研究了 NiCoS 纳米片@纳米线（NSNWs）结构的生长机制。此外，还对 NiCoS 的三种不同形态（纳米片、纳米片@纳米颗粒和 NSNWs 结构）进行了电化学测量，这三种形态是通过不同的反应阶段获得的。由于 NSNWs 结构具有相对较高的比表面积、电导率和有效的电子传输途径，因此与另外两种形态相比，所制备的 NiCoS NSNWs 结构在 1 A/g 的电流密度下表现出最大的比容量为 1777 F/g，在 10 A/g 的高扫描速率下具有最高的电容保持率（3000 次循环后为 83%），质量负载密度为 4.0 mg/cm。这些结果表明，NiCoS NSNWs 结构在超级电容器中有很大的应用潜力。
