Facile hydrothermal synthesis of urchin-like cobalt manganese spinel for high-performance supercapacitor applications.

A facile hydrothermal method has been adopted to synthesize the spherical urchin-like hierarchical CoMnO nanostructures on the nickel foam substrate. The as-synthesized urchins have an average diameter of ∼3-7μm with numerous self-assembled nanoneedles grown radically in all the directions from its center with a huge void space between them. For comparison, we have also studied the electrochemical as well as other physicochemical properties of parent simple CoO and MnO materials, which were also synthesized by a similar hydrothermal method.