Hollow Fe3O4/C spheres as superior lithium storage materials

Unique hollow Fe3O4/C spheres are prepared by a simple one-pot solvothermal method, with spinel structure and 750 nm in diameter identified by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM) techniques. The hollow Fe3O4/C spheres exhibit excellent cycling and rate performance as anode material for lithium ion batteries, delivering reversible specific capacities of 984 mAh g(-1) even after 70 cycles at 0.2C, 620 mAh g(-1) at 2 C, and 460 mAh g(-1) at 5 C. respectively. Lithium insertion mechanisms are also proposed in terms of the ex situ XRD analysis of the electrodes after discharged and charged to certain voltages together with cyclic voltammetry (CV) and voltage profile. Crown Copyright (C) 2011 Published by Elsevier B.V. All rights reserved.