Facile Synthesis of Metallic Co Hierarchical Nanostructured Microspheres by a Simple Solvothermal Process

The fabrication of hierarchical and complex micro/nanostructures using nanoparticles such as nanorods, nanoribbons, nanoplatelets, etc. as building blocks at different levels has become a hot topic in recent material research fields. In this study, facile synthesis of metallic cobalt hierarchical nanostructured microspheres was reported by a simple solvothermal process. The as-obtained products were well characterized by X-ray diffraction, scanning electron microscopy, transmission electron microscopy, Brunauer−Emmett−Teller analysis, and vibrating sample magnetometery. It was shown that the Co hierarchical nanostructured microspheres with a diameter of several micrometers are assembled from nanoplatelets with a thickness of about 20 nm and a width of 0.5−1.5 µm. A rational mechanism of formation was proposed on the basis of a range of contrasting experiments. The as-synthesized material exhibits ferromagnetic characteristics and a high surface area, showing potential applications for catalysts and other related micro- and nanodevices.