Porous cobalt oxide (Co3O4) nanorods: Facile syntheses, optical property and application in lithium-ion batteries

We developed a facile synthetic route of porous cobalt oxide (Co₃O₄) nanorods via a microemulsion-based method in combination with subsequent calcination process. The porous structure was formed by controlled decomposition of the microemulsion-synthesized precursor CoC₂O₄ nanorods without destruction of the original morphology. The as-prepared Co₃O₄ nanorods, consisting of small nanoparticles with diameter of 80–150 nm, had an average diameter of 200 nm and a length of 3–5 μm. The morphology and structure of synthesized samples were characterized by transmission electron microscopy and scanning electron microscopy. The phase and composition were investigated by X-ray powder diffraction and X-ray photoelectron spectroscopy. The optical property of Co₃O₄ nanorods was investigated. Moreover, the porous Co₃O₄ nanorods exhibited high electrochemical performance when applied as cathode materials for lithium-ion batteries, which gives them good potential applications.