Magnetite (Fe₃O₄) has been used as electrode materials in lithium ion batteries as it has a higher theoretical lithium ion storage capacity than that of commercial graphite. However, Fe₃O₄ anode materials have poor cyclic performance owing to agglomerations and huge volume change during lithium insertion/extraction.

Guoxiu Wang and co-workers, University of Technology, Sydney, Australia, have made uniform nanosized polyhedral single crystal magnetite by a low temperature hydrothermal method. Theoretical calculations, confirmed by a range of characterization techniques, showed that the nanocrystals had multiple facets, including (100), (010), (001), (110), (101), (011) and (111).

When applied as anode material in lithium ion cells, the nanocrystals demonstrated a high lithium storage capacity and a satisfactory cycling performance. In particular, magnetite nanocrystals can tolerate the volume change during the charge/discharge process, which maintains the integrity of the electrode. The nanocrystals outperform the previously reported Fe₃O₄ thin-films and carbon-coated Fe₃O₄.

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• Polyhedral Magnetite Nanocrystals with Multiple Facets: Facile Synthesis, Structural Modelling, Magnetic Property and Application for High Capacity Lithium Storage
  D. Su, J. Horvat, P. Munroe, H. Ahn, A. R. Ranjbartoreh, G. Wang,
  Chem. Eur. J. 2011.
  DOI: 10.1002/chem.201101939