Controllable fabrication of hierarchical top-converged Co3O4 nanowire array with enhanced lithium storage performance

Abstract

Nanostructured Co3O4 is one of the promising anode materials for lithium ion batteries (LIBs). Herein, a hierarchical top-converged Co3O4 nanowire array is prepared by the electrochemical corrosion of electrodeposited cobalt film and subsequent annealing treatment in air. In the corrosion process, a dissolution–recrystallization induced ripening process results in the morphology transformation from the initially formed nanosheets to nanowires, and the hierarchical top-converged nanowire array film is finally achieved. The as-prepared Co3O4 nanowire array electrode shows a reversible capacity of 0.54 mAh cm−2 (1213.49 mAh g−1) after 200 cycles at a current density of 0.1 mA cm−2 (224.72 mA g−1), manifesting higher capacity and excellent cycling stability. The electrode also demonstrates a good rate capability, with a reversible capacity of 0.26 mAh cm−2 (584.27 mAh g−1) at a relatively large current density of 0.8 mA cm−2 (1797.96 mA g−1). The enhanced lithium storage performance of the hierarchical top-converged nanowire array electrode is originated from its unique structural characteristics.