Preparation and characteristics of Co nanoporous magnetic materials synthesized by a template-free method

Abstract

We report a template-free hydrogen reduction approach to prepare cobalt nanoporous magnetic materials with various morphologies employing Co3O4 as precursors, which were obtained by thermal-decomposing CoCO3 intermediates. The kinetic control of experimental parameters of synthetic CoCO3 intermediates by a facile solvent-thermal route can be an effective strategy to tune the morphology of Co nanoporous structures. The microstructures, crystal structures or thermal characteristics of products at different stages were investigated to reveal the formation mechanism of the Co nanoporous structures. Magnetic measurement showed that the Co nanoporous structures with rhomb-like and prism-like morphology exhibited saturation magnetization (Ms) of 149.2 emu/g and 141.8 emu/g, and coercivity (Hcj) of 508.4 Oe and 554.9 Oe, respectively. The as-prepared Co ferromagnetic materials exhibited remarkably high coercivity values mainly due to the three dimensional nanoporous structures.