Synthesis of hierarchical Co₃O₄@C composite and its lithium storage property as anode material for rechargeable lithium ion batteries

Abstract

Carbon coated Co 3 O 4 (Co 3 O 4 @C) composite with hierarchical architecture is synthesised by hydrothermal and subsequent CH 4 chemical vapour deposition method. Based on the results obtained from morphology and structure characterisation, the possible formation process of the hierarchical Co 3 O 4 @C has been proposed. As an anode material for lithium ion batteries, Co 3 O 4 @C shows an improved electrochemical performance in the initial coulombic efficiency (63%), reversible capacity (775 mAh g 21 at 30th cycle) and cycling stability (83% capacity retention after 30 cycles). The performance is much better than the results obtained from hierarchical Co 3 O 4 particles. The excellent electrochemical performance of Co 3 O 4 @C can be attributed to the thin carbon layers formed over each Co 3 O 4 particle, which enhances the ionic/ electrical conductivity, and serves as a buffering agent to absorb the volume expansion during the charge/discharge cycles.

Mesoporous multi-valence manganese oxides composite nanotubes boosting long-life lithium-ion batteries

“…8, the Nyquist plot consists of a sloping line in the low frequency region and a semicircle in the mid-high frequency region, which is consistent with the typical EIS characteristics of LIBs. 44,45 Six Nyquist diagrams were fitted with ZSimpWin software, and a general equivalent circuit model was obtained. As seen from the inset part in Fig.…”