Morphology-controlled synthesis of Fe₃ O₄ / carbon nanostructures for lithium ion batteries

Morphology-controlled Fe₃ O₄ / carbon nanocomposites were synthesized by a solvothermal reaction followed by calcination under a nitrogen atmosphere. Flower-like structures, dispersed nanoflakes and hollow microspheres could be readily obtained by adjusting the concentrations of the reactants. Based on the time dependent structure evolution, a possible mechanism for the formation of the different morphologies under various conditions was discussed. The lithium storage properties of the different Fe₃ O₄ / carbon composites were compared. The flower-like sample shows the best electrochemical performance with the highest specific capacity of 227mAh / g at a current rate of 5 C while hollow microspheres and dispersed nanoflakes have specific capacities of only 45 and 10mAh / g, respectively.