A layer-by-layer assembly route to [Mn 1/3Co 1/3Ni 1/3]O 2 hollow spheres with electrochemical activity

Abstract

The monolayered nanosheets of layered [Mn 1/3Co 1/3Ni 1/3]O 2 are prepared by the exfoliation of protonated Li[Mn 1/3Co 1/3Ni 1/3]O 2 compound and applied as a precursor for synthesizing the hollow spheres of manganese cobalt nickel oxide. The hollow spheres of layered [Mn 1/3Co 1/3Ni 1/3]O 2 are synthesized via the layer-by-layer (LBL) coating of the nanosheets and polycations on the polystyrene (PS) beads and the following heat-treatment. According to powder X-ray diffraction and diffuse reflectance UV-vis spectroscopy, the layered crystal structure and optical property of [Mn 1/3Co 1/3Ni 1/3]O 2 nanosheets are well-maintained upon the coating on the PS beads. The high-resolution transmission electron microscopy clearly demonstrates the hollow sphere morphology of the obtained material. The electrode functionality of the [Mn 1/3Co 1/3Ni 1/3]O 2 hollow spheres is verified by cyclic voltammetry. © 2012 ElsevierLtd.Allrightsreserved.