Electrodeposited Sb and Sb/Sb2O3 nanoparticle coatings as anode materials for Li-ion batteries
Electrodeposited Sb and Sb/Sb2O3 nanoparticle coatings as anode materials for Li-ion batteries
复制标题
DOI：
10.1021/cm0624769
复制
发表时间：
2007-03-06
影响因子：
8.6
通讯作者：
Edstrom, Kristina
中科院分区：
文献类型：
--
作者：
Bryngelsson, Hanna;Eskhult, Jonas;Edstrom, Kristina
研究了酒石酸锑溶液制备的纯Sb或共沉积Sb和Sb2O3纳米粒子的恒流电沉积涂层作为锂离子电池的负极材料。结果表明，20-25% (w/w) Sb2O3的共沉积是由于在缓冲不良的溶液中，阴极的局部pH值增加（由于释放的酒石酸盐的质子化）。这导致了Sb2O3纳米颗粒的沉淀，并在沉积物中包裹了一些颗粒，并在其中包裹了一层Sb保护层。沉积物的计时电位循环，也使用SEM， TEM和XRD进行了表征，清楚地表明含有Sb2O3的沉积物作为阳极材料是优越的。经过50多次循环，Sb/Sb2O3涂层的比容量接近Sb理论值660 mA中心点h中心点g(-1)，而Sb涂层的比容量逐渐下降到250 mA中心点h中心点g（-1）左右。这表明，对于Sb/Sb2O3纳米颗粒涂层来说，显著的体积变化对Li3Sb形成和氧化的影响要小得多。性能的提高可以解释为在再氧化过程中Sb2O3的显著形成，在Sb/Sb2O3涂层中存在较小的Sb颗粒，以及在Sb/Sb2O3沉积层的第一次还原循环中在Sb基体中形成Li2O缓冲纳米颗粒。
Galvanostatically electrodeposited coatings of pure Sb or co-deposited Sb and Sb2O3 nanoparticles, prepared from antimony tartrate solutions, were studied as anode materials in Li-ion batteries. It is demonstrated that the co-deposition of 20-25% (w/w) Sb2O3 results from a local pH increase at the cathode (due to protonation of liberated tartrate) in poorly buffered solutions. This causes precipitation of Sb2O3 nanoparticles and inclusion of some of the particles in the deposit where they become coated with a protecting layer of Sb. Chronopotentiometric cycling of the deposits, which also were characterized using, e.g., SEM, TEM, and XRD, clearly showed that the Sb2O3-containing deposits were superior as anode materials. While the Sb/Sb2O3 coatings exhibited a specific capacity close to the Sb theoretical value of 660 mA center dot h center dot g(-1) during more than 50 cycles, the capacity for the Sb coatings gradually decreased to about 250 mA center dot h center dot g(-1). This indicates that the influence of the significant volume changes present upon the formation and oxidation of Li3Sb was much smaller for the Sb/Sb2O3 nanoparticle coatings. The improved performance can be explained by significant formation of Sb2O3 during the reoxidation, the presence of smaller Sb particles in the Sb/Sb2O3 coatings, and the formation of buffering nanoparticles of Li2O in a matrix of Sb during the first reduction cycle for the Sb/Sb2O3 deposits.