High Rate Electrochemical Capacitors from Three-Dimensional Arrays of Vanadium Nitride Functionalized Carbon Nanotubes
High Rate Electrochemical Capacitors from Three-Dimensional Arrays of Vanadium Nitride Functionalized Carbon Nanotubes
复制标题
DOI：
10.1021/jp205052f
复制
发表时间：
2011-11
影响因子：
3.7
通讯作者：
Li Zhang;C. M. Holt;E. Luber;B. Olsen;Huatao Wang;M. Danaie;Xinwei Cui;X. Tan;V. Lui;
中科院分区：
文献类型：
--
作者：
Li Zhang;C. M. Holt;E. Luber;B. Olsen;Huatao Wang;M. Danaie;Xinwei Cui;X. Tan;V. Lui;
开发了一种简单的方法来直接合成三维（3D）电化学超级电容阵列，由多壁碳纳米管共形覆盖的纳米晶氮化钒，牢固地锚定到玻璃碳或铬镍铁合金电极。这些纳米结构表现出289 F g-1的可观的比电容，这是在1 M KOH电解质中以20 mV s-1的扫描速率实现的。良好连接的高导电结构表现出卓越的速率能力;在1000 mV s-1的极高扫描速率下，相对于20 mV s-1，电容下降不到20%。VN的这种速率能力从未被报道过，并且对于任何其他氧化物或氮化物都是非常罕见的。这些3D阵列在恒流充放电循环期间也显示出接近理想的三角形电压分布。电化学循环后样品的分析表明，VN纳米微晶形态发生了可忽略的变化，但在…
A simple methodology is developed to directly synthesize three-dimensional (3D) electrochemically supercapacitive arrays, consisting of multiwalled carbon nanotubes conformally covered by nanocrystalline vanadium nitride, firmly anchored to glassy carbon or Inconel electrodes. These nanostructures demonstrate a respectable specific capacitance of 289 F g–1, which is achieved in 1 M KOH electrolyte at a scan rate of 20 mV s–1. The well-connected highly electrically conductive structures exhibit a superb rate capability; at a very high scan rate of 1000 mV s–1 there is less than a 20% drop in the capacitance relative to 20 mV s–1. Such rate capability has never been reported for VN and is highly unusual for any other oxide or nitride. These 3D arrays also display nearly ideal triangular voltage profiles during constant current charge–discharge cycling. Analysis of the post-electrochemically cycled samples indicates negligible changes occurring in the VN nanocrystallite morphology, but a modification in the ...