State Key Laboratory of Advanced Technology for Materials Synthesis and Processing, Wuhan University of Technology , Wuhan 430070, People's Republic of China.
Department of Chemistry and Biochemistry, University of California , Los Angeles, California 90095, United States.
ACS Appl Mater Interfaces. 2016 Feb 3;8(4):2812-8. doi: 10.1021/acsami.5b11510. Epub 2016 Jan 21.
Hierarchical Co2V2O7 nanosheets consisted of interconnected nanoparticles are synthesized by a facile method using graphene oxide as the template. The electrochemical reaction mechanism of the Co2V2O7 nanosheets is thoroughly investigated by in situ XRD and ex situ TEM. The initial Co2V2O7 transforms into CoO nanoparticles and vanadium oxides in the first cycle, and the following reversible conversion reaction mainly occurs between CoO and Co and lithiation/delithiation of the vanadium oxides. The Co2V2O7 nanosheet displays a high reversible capacity (962 mAh/g at 0.5 A/g) and remarkable high rate capability. When cycled at 5.0 A/g, a reversible capacity of 441 mAh/g can be retained after 900 cycles. The stable high capacity and excellent rate capability make the hierarchical Co2V2O7 nanosheets a promising anode material for lithium-ion batteries.
采用简单的方法，以氧化石墨烯为模板合成了由相互连接的纳米颗粒组成的层状 Co2V2O7 纳米片。通过原位 XRD 和非原位 TEM 深入研究了 Co2V2O7 纳米片的电化学反应机理。在第一个循环中，初始的 Co2V2O7 转变为 CoO 纳米颗粒和钒氧化物，随后 CoO 和 Co 之间的可逆转化反应以及钒氧化物的插层/脱层主要发生。Co2V2O7 纳米片显示出高可逆容量（在 0.5 A/g 时为 962 mAh/g）和出色的倍率性能。当以 5.0 A/g 循环时，在 900 次循环后可保持 441 mAh/g 的可逆容量。稳定的高容量和优异的倍率性能使分层 Co2V2O7 纳米片成为锂离子电池有前途的阳极材料。
