Xing Ling-Li, Zhao Gang-Gang, Huang Ke-Jing, Wu Xu
College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
Dalton Trans. 2018 Feb 13;47(7):2256-2265. doi: 10.1039/c7dt04660j.
Various VO three-dimensional nanostructures are synthesized using a facile template-free hydrothermal method and evaluated for use as supercapacitor electrode materials. As a result, the yolk-shell structure assembled from ultrathin nanosheets shows the best electrochemical performance, with a specific capacitance of 704.17 F g at 1.0 A g and a high capacity retention of 89% over 4000 cycles at 3.0 A g. In addition, a continuous three-dimensional porous coralline-shaped carbon is synthesized from osmanthus and has a large Brunauer-Emmett-Teller surface area of 2840.88 m g. Then, an asymmetric supercapacitor is developed using the as-prepared yolk-shell VO as a positive electrode and the osmanthus derived coralline-shaped carbon as a negative electrode. This exhibits an energy density of 29.49 W h kg at a power density of 800 W kg with a good cycling performance that retains 90.6% of its initial capacity after 2000 cycles at 3.0 A g. Furthermore, two cells in series can easily brightly light up a light-emitting diode (3 V), further demonstrating the great potential of the prepared materials for high-performance supercapacitor devices.
采用简便的无模板水热法合成了各种VO三维纳米结构，并对其作为超级电容器电极材料的性能进行了评估。结果表明，由超薄纳米片组装而成的蛋黄壳结构表现出最佳的电化学性能，在1.0 A g时比电容为704.17 F g，在3.0 A g下4000次循环后的容量保持率高达89%。此外，以桂花为原料合成了具有连续三维多孔珊瑚状的碳，其比表面积高达2840.88 m g。然后，以制备的蛋黄壳VO为正极，以桂花衍生的珊瑚状碳为负极，研制了一种不对称超级电容器。该超级电容器在功率密度为800 W kg时的能量密度为29.49 W h kg，在3.0 A g下2000次循环后具有良好的循环性能，容量保持率为90.6%。此外，两个串联的电池可以轻松地点亮一个发光二极管（3 V），进一步证明了所制备材料在高性能超级电容器器件方面的巨大潜力。
