Template-Free Electrochemical Deposition of Interconnected ZnSb Nanoflakes for Li-Ion Battery Anodes
Template-Free Electrochemical Deposition of Interconnected ZnSb Nanoflakes for Li-Ion Battery Anodes
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DOI：
10.1021/cm103068v
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发表时间：
2011-02-22
影响因子：
8.6
通讯作者：
Yan, Qingyu
中科院分区：
文献类型：
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作者：
Saadat, Somaye;Tay, Yee Yan;Yan, Qingyu
研究了一种无模板电化学沉积法单步制备ZnSb纳米结构的方法。结果表明，通过调整前驱体浓度、施加电压和衬底类型，可以得到具有可控组成的ZnSb纳米片、纳米线或纳米颗粒。在不添加任何粘结剂的情况下，将沉积在铜箔上的ZnSb纳米结构直接用作锂离子电池阳极。电化学分析表明，互连ZnSb纳米片具有较高的放电容量和稳定的性能，优于ZnSb纳米线和纳米颗粒。ZnSb纳米片的初始放电容量为735 mA h/g，初始哥伦比亚效率为85%，在100 mA/g （0.18 C）电流密度下，经过70次循环后，ZnSb纳米片的放电容量为500 mA h/g，库仑效率为98%。ZnSb纳米线和纳米颗粒在相同电流密度下循环70次后的容量分别为190和40 mA h/g。互连ZnSb纳米片性能的提高主要归功于其开放的结构，具有较大的表面积和较小的晶粒，有利于Li离子的扩散，缓冲锂嵌入过程中较大的体积波动。
A single-step fabrication of ZnSb nanostructures using template-free electrochemical deposition was developed. Results have indicated that ZnSb nanoflakes, nanowires, or nanoparticles with controlled composition could be obtained by adjusting the precursor concentration, applied voltage, and substrate type. The ZnSb nanostructures deposited on Cu foils were directly used as Li-ion battery anodes without the addition of any binder. Electrochemical analyses revealed that the interconnected ZnSb nanoflakes depicted high discharge capacities and a stable performance, which were better than that of ZnSb nanowires and nanoparticles. With an initial discharge capacity of 735 mA h/g and an initial Columbic efficiency of 85%, the ZnSb nanoflakes maintained a discharge capacity of 500 mA h/g with a Coulombic efficiency of 98% after 70 cycles at a current density of 100 mA/g (0.18 C). The ZnSb nanowires and nanoparticles showed a capacity of 190 and 40 mA h/g, respectively, after 70 cycles at the same current density. The improved performance of the interconnected ZnSb nanoflakes is attributed to their open structure, with a large surface area and small crystal grains, to facilitate the diffusion of Li ions and to buffer the large volume swings during the lithium intercalation process.