School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116, People's Republic of China.
School of Materials Science and Engineering, China University of Mining and Technology, Xuzhou 221116, People's Republic of China.
J Colloid Interface Sci. 2018 Dec 1;531:83-90. doi: 10.1016/j.jcis.2018.07.044. Epub 2018 Jul 17.
Metal-organic frameworks (MOFs), serving as a promising electrode material in the supercapacitors, have attracted tremendous interests in recent years. Here, through modifying the molar ratio of the Ni and Co, we have successfully fabricated Ni-MOF and Ni/Co-MOF by a facile hydrothermal method. The Ni/Co-MOF with a dandelion-like hollow structure shows an excellent specific capacitance of 758 F g at 1 A g in the three-electrode system. Comparing with Ni-MOF, the obtained Ni/Co-MOF has a better rate capacitance (89% retention at 10 A g) and cycling life (75% retention after 5000 circulations). Besides, the assembled asymmetric supercapacitor based on Ni/Co-MOF and active carbon exhibits a high specific energy density of 20.9 W h kg at the power density of 800 W kg. All these results demonstrate that the mixed-metal strategy is an effective way to optimize the morphology and improve the electrochemical property of the MOFs.
金属-有机骨架（MOFs）作为超级电容器中的一种有前途的电极材料，近年来引起了极大的关注。在这里，我们通过调节 Ni 和 Co 的摩尔比，通过简便的水热法成功制备了 Ni-MOF 和 Ni/Co-MOF。具有蒲公英状中空结构的 Ni/Co-MOF 在三电极系统中具有 758 F g 的出色比电容，在 1 A g 时的电流密度下。与 Ni-MOF 相比，所获得的 Ni/Co-MOF 具有更好的倍率电容（在 10 A g 时保持 89%）和循环寿命（5000 次循环后保持 75%）。此外，基于 Ni/Co-MOF 和活性炭组装的非对称超级电容器在 800 W kg 的功率密度下表现出 20.9 Wh kg 的高比能量密度。所有这些结果表明，混合金属策略是优化 MOFs 形态和改善其电化学性能的有效方法。
