Self-assembled hairy ball-like Co3O4 nanostructures for lithium ion batteries

Nanostructured Co3O4 in a novel hairy ball-like morphology is successfully synthesized from self-assembled hierarchical Co(CO3)0.35Cl0.2(OH)1.10·1.74H2O precursors via a facile hydrothermal method and subsequent annealing in air. The morphological evolution of the Co(CO3)0.35Cl0.2(OH)1.10·1.74H2O precursors is investigated by examining the different reaction times during the synthesis. First, fan-shaped microplates are formed, followed by nanowires grown on the surface of the plates. Subsequently, with an extended growth reaction time, the nanowires grow longer to form the hairy ball-like structures. The Co3O4, obtained from thermal decomposition of the Co(CO3)0.35Cl0.2(OH)1.10·1.74H2O precursor in air at 400 °C, exhibits highly reversible capacities as an anode material in lithium ion batteries, which retains 860 mA h g−1 at 100 mA g−1 after 50 cycles, with good cycling stabilities and rate capabilities.