Fe3O4 nanoparticles-wrapped carbon nanofibers as high-performance anode for lithium-ion battery

One-dimensional hierarchical nanostructures composed of Fe3O4 nanoparticles and carbon nanofibers (CNFs) have been successfully synthesized through a facile solvothermal method followed by a simple thermal annealing treatment. X-ray diffraction and electron microscopy reveal that Fe3O4 nanoparticles with a size of 80–100 nm are uniformly dispersed on CNFs. The Fe3O4/CNFs nanocomposites show an enhanced reversible capacity and excellent rate performance as anode for Li-ion battery. The reversible capacity of the nanocomposites retains 684 mAh g−1 after 55 cycles at 100 mA g−1. Even when cycled at various rate (100, 200, 500, 1000, and 2000 mA g−1) for 50 cycles, the capacity can recover to 757 mAh g−1 at the current of 100 mA g−1. The enhanced electrochemical performances are attributed to the characteristics of interconnected one-dimensional nanostructures that provide three-dimensional networks for Li-ion diffusion and electron transfer, and can further accommodate the volumetric change of Fe3O4 nanoparticles during charge–discharge cycling.