• 文献标题:   Engineering Hierarchical CoO Nanospheres Wrapped by Graphene via Controllable Sulfur Doping for Superior Li Ion Storage
  • 文献类型:   Article
  • 作  者:   HU YF, LI ZC, HU ZC, WANG L, MA RG, WANG JC
  • 作者关键词:   hierarchical nanosphere, lithium ion batterie, metal oxide, sulfur doping
  • 出版物名称:   SMALL
  • ISSN:   1613-6810 EI 1613-6829
  • 通讯作者地址:   Chinese Acad Sci
  • 被引频次:   0
  • DOI:   10.1002/smll.202003643 EA SEP 2020
  • 出版年:   2020

▎ 摘  要

The inferior conductivity and large volume expansion impair the widespread applications of metal oxide-based anode materials for lithium-ion batteries. To address these issues, herein an efficient strategy of structural engineering is proposed to improve lithium storage performance of hierarchical CoO nanospheres wrapped by graphene via controllable S-doping (CoOS0.1 @ G). S-doping promotes the Li(+)diffusion kinetics of CoO by expanding the interplanar spacing of CoO, lowering the activation energy, and improving the pseudocapacitance contribution. Meanwhile, the electronic structure of CoO is adjusted by S-doping as confirmed by density functional theory calculations, thus enhancing the conductivity. Finite element analysis reveals that the produced Li2S during lithiation improves the structural stability of the S-doped electrode, which is further confirmed by experimental observation. As expected, CoOS0.1 @ G exhibits excellent lithium storage performance with an initial discharge capacity of 1974 mAh g(-1)at 100 mA g(-1), and high discharge capacity of 1573 mAh g(-1)after 400 cycles at 500 mA g(-1). It is believed that the insights into the structural doping enlighten research to explore other metal oxides for fast and stable Li ion storage.