Core-shell Fe@Fe3C/C nanocomposites as anode materials for Li ion batteries

Core-shell Fe@Fe3C/C nanocomposites were prepared by adopting alpha-FeOOH nanorods as the Fe precursor though a simple and green route. The obtained core-shell nanospheres consisted of single crystalline Fe cores (20-50 nm) coated with well-proportioned Fe3C shell (similar to 8 nm) in amorphous carbon. The composites delivered a reversible capacity of similar to 500 mAh g(-1) after 30 cycles. However, no obvious changes were observed in the XRD patterns of Fe@Fe3C/C electrodes before and after the discharge process, indicating that Fe and Fe3C are inactive for lithium storage. Many characterizations were performed to propose a reasonable explanation about the Li storage capacity. (C) 2012 Elsevier Ltd. All rights reserved.