Enhanced Li-ion battery performances of yolk-shell Fe3O4@C anodes with Fe3C catalyst

Most metal oxides with high theoretical specific capacities including Fe3O4 are promising lithium battery (LIB) anode materials, which capacities are larger than that of current commercial graphite. However, most of these anodes suffer from the defects of poor electronic conductivity, large volumetric expansion upon lithiation and low coulombic efficiency. Here, as a typical work, we develop and fabricate a novel composite of yolk-shell structured Fe3O4@C mixed with Fe3C catalysts directly used as LIB anodes. The anode of Fe3O4 nanospheres protected by the carbon shell and added with the Fe3C catalysts, can deliver obviously enhanced LIB performance. Especially, tested at 1000 mA g(-1), the electrodes afforded high capacity of 600 mAh g(-1) after 300 cycles at room temperature and high reversible capacity of 380 mAh g(-1) even after 700 cycles at a relatively low temperature of 0 degrees C. The enhanced LIB performance could be associated with the contribution of carbon shell and Fe3C adding. These results revealed the potential applications of Fe3C/Fe3O4@C nanostructure materials as anodes for LIBs. (C) 2017 Elsevier Ltd. All rights reserved.