Branched Co₃O₄/Fe₂O₃ nanowires as high capacity lithium-ion battery anodes

We report a facile, two-step hydrothermal synthesis of a novel Co₃O₄/α-Fe₂O₃ branched nanowire heterostructure, which can serve as a good candidate for lithium-ion battery anodes with high Li⁺ storage capacity and stability. The single-crystalline, primary Co₃O₄ nanowire trunk arrays directly grown on Ti substrates allow for efficient electrical and ionic transport. The secondary α-Fe₂O₃ branches provide enhanced surface area and high theoretical Li⁺ storage capacity, and can also serve as volume spacers between neighboring Co₃O₄ NW arrays to maintain electrolyte penetration as well as reduce the aggregation during Li⁺ intercalation, thus leading to improved electrochemical energy storage performance.