Directional preparation of cobalt oxide nanoflakes grown on cobalt nanowires as composite cathode for high-performance alkaline batteries

Abstract Synthesis of multicomponent core/branch arrays is important for development of advanced energy storage devices. Herein we fabricate porous CoO@Co core/branch arrays by successive hydrothermal + electrodeposition methods CoO nanoflakes branch is uniformly coated on the Co nanowire core forming composite core/branch arrays (CBAs). The CoO@Co CBAs possess combined properties of highly porous structure and strong mechanical stability. As cathode for alkaline batteries, the obtained CoO@Co CBAs exhibit good electrochemical performances with high a capacity of 91.5 mAh g −1 at 1 A g −1 and stable high-rate cycling life (73.5 mAh g −1 after 12,000 cycles at 10 A g −1 ). The hierarchical core/branch architecture provides positive roles in the enhancement of electrochemical properties with fast electronic transportation path, and short diffusion channels of ions. Our finding offers a new way to construct high-performance cathode of alkaline batteries.