Zhang Yu, Zhang Yihe, Zhang Deyang, Sun Li
Beijing Key Laboratory of Materials Utilization of Nonmetallic Minerals and Solid Wastes, National Laboratory of Mineral Materials, School of Materials Science and Technology, China University of Geosciences, Beijing, 100083, PR China.
Dalton Trans. 2017 Jul 25;46(29):9457-9465. doi: 10.1039/c7dt01654a.
Here, we report a facile method to fabricate NiCoO nanoneedles on mesocarbon microbeads (MCMB) and form a unique urchin-like core-shell structure. In this composite, the MCMB not only provided high conductivity to benefit effective electron transfer, but also offered abundant adsorption points to load the NiCoO nanoneedles. The aggregation of the NiCoO nanoneedles was therefore alleviated and each NiCoO grain was unfolded to gain easy access to the electrolyte for efficient ion transfer. When the NiCoO@MCMB composite was evaluated as an electrode material for supercapacitors, a synergistic effect was exerted with high specific capacitance (458 F g at 1 A g) and large reversibility (116% capacitance retention after 3000 cycles), both of which were of great advantage over individual MCMB and NiCoO nanoneedles. The NiCoO@MCMB was also used to construct a symmetric supercapacitor, which showed enlarged voltage profiles and could light the LED device for a few minutes, further confirming its excellent electrochemical performance.
在此，我们报道了一种在中间相炭微球（MCMB）上制备NiCoO纳米针并形成独特的海胆状核壳结构的简便方法。在这种复合材料中，MCMB不仅提供高导电性以利于有效的电子转移，还提供丰富的吸附位点来负载NiCoO纳米针。因此，NiCoO纳米针的聚集得到缓解，并且每个NiCoO颗粒都展开以易于接触电解质实现高效的离子转移。当将NiCoO@MCMB复合材料作为超级电容器的电极材料进行评估时，其表现出协同效应，具有高比电容（在1 A g下为458 F g）和大的可逆性（3000次循环后电容保持率为116%），这两者相对于单独的MCMB和NiCoO纳米针都具有很大优势。NiCoO@MCMB还用于构建对称超级电容器，其显示出扩大的电压分布并且可以使LED装置点亮几分钟，进一步证实了其优异的电化学性能。
