Excellent cycling stabilities of a novel calliandra-like Co₃O₄ acted as anode materials for the lithium-ion battery

Herein, a hierarchical calliandra-like Co₃O₄ is successfully synthesized via a simple carbon sphere and hydroxypropyl cellulose assisted hydrothermal process. X-ray diffraction (XRD), scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) and transmission electron microscopy (TEM) characteristics results indicate that the hierarchical Co₃O₄ spheres are 3–6 μm in diameter and belong to spinel structure. Each Co₃O₄ sphere is consisted of radially oriented nanocystals accumulated nanorods building blocks. The formation mechanism for this structure maybe ascribed to the collaboration effect of carbon sphere and hydroxypropyl cellulose, which act as hard template and dispersion stabilizer respectively. The calliandra-like Co₃O₄ particles exhibit satisfied electrochemical performance with high specific capacities and good rate capabilities, especially superior cycling stability when used as anode active materials in the lithium-ion batteries, which release an initial discharge capacity of 1139.42 mA h g⁻¹ at 200 mA g⁻¹, and maintain a reversible capacity of 734.64 mA h g⁻¹ after 500 cycles.