Rugated porous Fe ₃O ₄ thin films as stable binder-free anode materials for lithium ion batteries

Rugated porous Fe ₃O ₄ thin films were synthesized by a facile multi-pulse electrochemical anodization method. The fabricated Fe ₃O ₄ films are directly grown on Fe, featuring nano-channels with periodically rugated channel walls running throughout the film thickness direction. Electrochemical measurements show that the as-prepared Fe ₃O ₄ films readily serve as high-performance anode materials for lithium ion batteries with a specific capacity of 1100, 880 and 660 mA h g ^-1 at 0.1, 0.2, and 0.5 C, respectively, which compared favorably with the conventional straight-channel counterparts fabricated by DC anodization. Moreover, the cycling capability test of the novel electrode at 0.1 C for 100 cycles shows a steady charge/discharge platform, indicating a high cycling stability and structural robustness. The observed improvements of the rugated Fe ₃O ₄ films as lithium ion battery anode materials are attributed to their special periodic rugated nanostructures. © 2012 The Royal Society of Chemistry.