Facile synthesis of highly ordered mesoporous Co3O4 inverse opals as a high-performance electrocatalyst
Abstract
In this study , highly ordered mesoporous Co 3 O 4 inverse opals are synthesized using polystyrene beads as a hard template , followed by a calcination in air. The morphology and crystalline structure of the mesoporous Co 3 O 4 are investigated by scanning electron microscopy and X – ray diffraction techniques . The characterizations reveal that the thickness of the pore walls of the inverse opals is in the range of a few to a few tens of nanometers, the average diameter of the pores is in the range of 260 – 300 nm , and the mesoporous Co 3 O 4 has a spinel crystalline structure. The electrocatalytic properties of the materials are investigated by the oxygen evolution reaction . The result s show a superior activity of the mesoporous structure with a small Tafel slope and a low overpotential in the alkaline medium compared to the nanoparticle counterpart .