Co3O4/C nanocapsules with onion-like carbon shells as anode material for lithium ion batteries

Xianguo Liu, Siu Wing Or, Chuangui Jin, Yaohui Lv, Weihuo Li, Chao Feng, Feng Xiao, Yuping Sun

Research output: Journal article publicationJournal articleAcademic researchpeer-review

63 Citations (Scopus)

Abstract

The synthesis and characterization of core/shell-type Co3O4/C nanocapsules for application as anode material in lithium ion batteries are reported in this paper. The synthesis process involves the preparation of Co/C nanocapsules using a modified arc-discharge method and the annealing of the Co/C nanocapsules at 300 C for 2 h in air. The as-synthesized products show a spherical shape and a core/shell-type structure in which a Co3O4nanoparticle core of diameter 10-30 nm is encapsulated by an onion-like carbon shell of thickness approximately 1 nm. The Co/C nanocapsules can be stable below 130 C, and be oxidized above 205 C in air. The Co3O4/C nanocapsules deliver an initial discharge capacity of 1467.6 mAh g-1at 0.5 C and maintain a high reversible capacity of 1026.9 mAh g-1after 50 charge-discharge cycles, much higher than the Co3O4nanoparticles (471.5 mAh g-1). A postmortem analysis of the Co3O4and Co3O4/C anodes subjected to prolonged cycling reveals the existence of a lower degree of surface cracking and particle breakage in the Co3O4/C anode than the Co3O4anode. The improved electrochemical performance and structural stability in the Co3O4/C nanocapsules are attributed to the enhanced electrical conductivity and structural buffering provided by the onion-like carbon shell.
Original languageEnglish
Pages (from-to)140-146
Number of pages7
JournalElectrochimica Acta
Volume100
DOIs
Publication statusPublished - 30 Jun 2013

Keywords

  • Anode electrode
  • Carbon layer
  • Cobalt oxide
  • Lithium ion batteries

ASJC Scopus subject areas

  • Chemical Engineering(all)
  • Electrochemistry

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