• 文献标题:   Manipulation of Edge-Site Fe-N-2 Moiety on Holey Fe, N Codoped Graphene to Promote the Cycle Stability and Rate Capacity of Li-S Batteries
  • 文献类型:   Article
  • 作  者:   WANG YZ, ADEKOYA D, SUN JQ, TANG TY, QIU HL, XU L, ZHANG SQ, HOU YL
  • 作者关键词:   carbonization proces, fe n codoped carbon, fen2 moiety, holey graphene, lisulfur batterie
  • 出版物名称:   ADVANCED FUNCTIONAL MATERIALS
  • ISSN:   1616-301X EI 1616-3028
  • 通讯作者地址:   Peking Univ
  • 被引频次:   29
  • DOI:   10.1002/adfm.201807485
  • 出版年:   2019

▎ 摘  要

Graphene-based materials have been widely studied to overcome the hurdles of Li-S batteries, but suffer from low adsorptivity to polar polysulfide species, slow mass transport of Li+ ions, and severe irreversible agglomeration. Herein, via a one-step scalable calcination process, a holey Fe, N codoped graphene (HFeNG) is successfully synthesized to address these problems. Diverging by the holey structures, the Fe atoms are anchored by four N atoms (Fe-N-4 moiety) or two N atoms (Fe-N-2 moiety) localized on the graphene sheets and edge of holes, respectively, which is confirmed by X-ray absorption spectroscopy and density functional theory calculations. The unique holey structures not only promote the mass transport of lithium ions, but also prohibit the transportation of polysulfides across these additional channels via strong adsorption forces of Fe-N-2 moiety at the edges. The as-obtained HFeNG delivers a high rate capacity of 810 mAh g(-1) at 5 C and a stable cycling performance with the capacity decay of 0.083% per cycle at 0.5 C. The concept of holey structure and introduction of polar moieties could be extended to other carbon and 2D nanostructures for energy storage and conversion devices such as supercapacitors, alkali-ion batteries, metal-air batteries, and metal-halogen batteries.