One-pot synthesis of uniform Fe3O4 nanocrystals encapsulated in interconnected carbon nanospheres for superior lithium storage capability
One-pot synthesis of uniform Fe3O4 nanocrystals encapsulated in interconnected carbon nanospheres for superior lithium storage capability
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DOI：
10.1016/j.carbon.2013.01.056
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发表时间：
2013-06
期刊：
影响因子：
10.9
通讯作者：
N. Zhao;Shan-Luo Wu;C. He;Zhiyuan Wang;C. Shi;E. Liu;Jiajun Li
中科院分区：
文献类型：
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作者：
N. Zhao;Shan-Luo Wu;C. He;Zhiyuan Wang;C. Shi;E. Liu;Jiajun Li
通过一步水热法和氩气退火制备了封装在互连碳纳米球（~60nm）中的用于高倍率锂离子电池阳极的均匀且小的Fe3O4纳米晶体（~9nm），可用于制备封装在互连碳纳米球中的多种金属氧化物纳米晶体。所合成的互连Fe3O4@C纳米球作为锂离子电池负极材料表现出高性能，例如高可逆锂存储容量（50次循环后在1C下为784mAh/g）、高库仑效率（∼99%）、优异的循环稳定性和优异的倍率性能（5C下为568mAh/g，10C下为379mAh/g）。 凭借其独特的结构：封装在互连导电碳纳米球中的纳米级Fe3O4纳米晶体不仅为锂离子插入提供了大量的可接近的活性位点，以及良好的导电性和短的扩散长度以供锂离子传输，而且可以有效地规避与锂插入/脱出相关的体积膨胀/收缩。
Uniform and small Fe3O4nanocrystals (∼9nm) encapsulated in interconnected carbon nanospheres (∼60nm) for a high-rate Li-ion battery anode have been fabricated by a one-step hydrothermal process followed by annealing under Ar, which can be applied for the preparation of a number of metal oxide nanocrystals encapsulated in interconnected carbon nanospheres. The as-synthesized interconnected Fe3O4@C nanospheres displayed high performance as an anode material for Li-ion battery, such as high reversible lithium storage capacity (784mAh/g at 1 C after 50 cycles), high Coulombic efficiency (∼99%), excellent cycling stability, and superior rate capability (568mAh/g at 5 C and 379mAh/g at 10 C) by virtue of their unique structure: the nanosized Fe3O4nanocrystals encapsulated in interconnected conductive carbon nanospheres not only endow large quantity of accessible active sites for lithium ion insertion as well as good conductivity and short diffusion length for lithium ion transport but also can effectively circumvent the volume expansion/contraction associated with lithium insertion/extraction.