Template-free synthesis of Co nanoporous structures and their electromagnetic wave absorption properties

Abstract: We report a template-free hydrogen reduction approach to prepare sponge-like cobalt nanoporous structures employing Co3O4 as precursors, which were obtained by thermal-decomposing of CoCO3 intermediates prepared by a facile solvent-thermal route. A three-step formation mechanism for the Co nanoporous structures was proposed. The epoxy resin composites with 65wt.% rhomb-like and rod-like samples showed efficient electromagnetic wave absorption characteristics (RL<−20dB) in the ranges of 12.8–18GHz and 11.2–18GHz over absorber thicknesses of 1.05–1.5mm and 1.0–1.6mm, respectively. It is believed that the porous metallic magnets would gain wide applications as more efficient electromagnetic wave absorbers. [Copyright &y& Elsevier]