Fe₃O₄/Fe/Carbon Composite and Its Application as Anode Material for Lithium-Ion Batteries

A plum pudding-like Fe(3)O(4)/Fe/carbon composite was synthesized by a sol-gel polymerization followed by a heat-treatment process and characterized by X-ray diffraction, Raman spectroscopic analysis, thermogravimetric analysis, scanning electron microscopy with energy-dispersive spectroscopy, transmission electron microscopy, and electrochemical test. In this composite, uniform spherical Fe(3)O(4)/Fe nanoparticles of about 100 nm were embedded into carbon matrix with high monodispersion. As-prepared Fe(3)O(4)/Fe/carbon composite electrode exhibits a stable and reversible capacity of over 600 mA h g(-1) at a current of 50 mA g(-1) between 0.002 V and 3.0 V, as well as excellent rate capability. The plum pudding-like structure, in which trace Fe promotes conductivity and carbon matrix mediates the volume change, can enhance the cycling performance and rate capability of Fe(3)O(4) electrode. This unique structure is valuable for the preparation of other electrode materials.