A facile microwave-assisted route to Co(OH)2 and Co3O4 nanosheet for Li-ion battery

A facile microwave-assisted synthetic route has been successfully developed for preparing hexagonal Co(OH)2 nanosheets with average width of 2 μm and thickness of 100 nm. Co(OH)2 can further convert to porous Co3O4 nanosheets via thermal decomposition. Their phases, structures and morphologies were investigated by X-ray diffraction (XRD), atomic force microscopy (AFM), and transmission electron microscopy (TEM). Both Co(OH)2 and Co3O4 nanosheets can serve as potential candidates for anodes of Li-ion battery. The electrochemical study revealed that Co(OH)2 and Co3O4 nanosheets delivered a reversible capacity of 600 and 700 mA h g−1 after 40 cycles, respectively. Cyclic voltammetry (CV) curves also confirmed the relative stability of the as-synthesized electrode materials. This effective microwave-assisted route may be a promising approach for preparing other transition metal hydroxide/oxides for energy applications.