Porous layer assembled hierarchical CoO as anode materials for lithium-ion batteries

The flower-like CoO particles with three-dimensional structure have been achieved by inheriting the flower-like framework of β-Co(OH) particles fabricated by a facile solvothermal method without any surfactant. The obtained CoO microflower, which was composed of large amounts of self-assembled porous ultrathin nanosheets, exhibited excellent electrochemical performances in terms of high specific capacity and good cycle stability when being evaluated as anode materials for lithium-ion battery. Specifically, a high reversible capacity of above 1100 mA h g was achieved after 50 cycles at the current density of 296 mA g. Hierarchical flower-like structure with mesoporous was considered as providing more active sites for Li insertion and paths for transport of Li, which led to faster lithium-ion diffusion. CoO porous flower-like nanostructures possessed significant potential application in energy storage systems.