MoO2/Mo2C hybrid Nanowires As Anode Materials for High Performance Lithium Ion Batteries

Molybdenum oxides, mainly including MoO₃ and MoO₂, are attractive materials with potential applications in catalysis, sensors and energy storage. Owing to the good electronic conductivity, high stability and density, MoO₂ was proposed as a host material for lithium ions. However, the application of MoO₂ as anode material for lithium ion batteries was limited in the early research, due to the low capacity and poor cycling stability resulting from the bulky dimensions, the consequential slow kinetics and huge volume changes during the charge/discharge process. To improve the performance of MoO₂, a most promising way is to design and construct nanostructured composites[1-3].

   Here we report on a facile synthesis of MoO₂/Mo₂C hybrid nanowires through simple calcination using MoO_x/amine nanowires as a precursor. The small diameters of the nanowires ensure fast lithium ion insertion and extraction, while the long dimensions benefit good electron transport between wires. Besides, The electrochemical inactive Mo₂C with a high specific conductance distinctly increases the structural stability and electronic conductivity of the hybrid nanowires. As a result, the cycling and rate performance of the hybrid nanowires is remarkably enhanced. At a current density of 1000 mA/g, a discharge capacity of ~ 700 mAh/g is still retained after 300 cycles, which indicates the MoO₂/Mo₂C hybrid nanowires a promising anode material for high performance lithium ion batteries.

Acknowledgements

This work was financially supported by the National Natural Science Foundation of China (Nos. 51402110, and 51231003), and the Fundamental Research Funds for the Central Universities (2013ZM0002).

References

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