Preparation and characterization of hexagonal mesoporous β-Co(OH)2 nanorings

Abstract Herein, a convenient and cost-effective approach carried out for the synthesis of hexagonal mesoporous β-cobalt hydroxides nanorings via chemical precipitation. Transmission electron microscopic and X-ray diffraction results reveals that these nanorings mostly consist of β-Co(OH) 2 with well crystalline hexagonal brucite like structure. The inert gas sorption-desorption measurements represents the mesoporous nature of the NPs. The Brunauer Emmett Teller surface area and average pore size of the as synthesized nanoparticles were about 210 m 2 /g and 5 nm. The especial mesoporous structures with excellent specific area are the reason for the good electrochemical capacitance performance and superior cyclic stability (only about 1% decay) in supercapacitor application. The as prepared nanoparticles have been used for oxygen evolution reaction. The oxygen evolution reaction performance is related to the active surface area of the nanoparticles due to the formation of mesoporous structure within the cobalt hydroxide nanoparticles. Furthermore, the presented facile synthetic process, which does not need any surfactant or template, could be extended to the preparation of other nanomaterials with excellent morphologies for supercapacitor and oxygen evolution reaction applications.