Fabrication and characterization of Fe 3O 4-based Cu nanostructured electrode for Li-ion battery

Abstract

Fe 3O 4-based Cu nanostructured electrodes for Li-ion cells are fabricated by a two-step electrochemical process. Cu nanorod arrays acting as current collectors are first prepared on a thin copper disk by alumina template-assisted electrodeposition. The active material of Fe 3O 4 is electrochemically deposited onto the Cu nanorod arrays by potentiostatic deposition. X-ray diffraction identifies textured growth for both the Cu nanorods and Fe 3O 4. Scanning electron microscopic observation further reveals that the active material are deposited between the Cu nanorods, and a 30 s deposition of Fe 3O 4 is sufficient to fill up the inter-rod space under the currently employed condition. Longer electroplating time leads to the coalescence of Fe 3O 4 particles and the formation of bulky Fe 3O 4 islands on the top of the Cu nanorods. Electrochemical properties of the nanostructured electrodes are studied by conventional charge/discharge tests. The results show that the rate capabilities of the nanostructured electrodes are better compared to those of the planar electrodes and the coalescence of Fe 3O 4 particles is detrimental to achieve sustained reversible capacities.