Cost-effective approach to large-scale synthesis of cobalt ferrite nanoparticles

Well crystalline cobalt ferrite CoFe₂O₄ nanoparticles (50-100 nm) were produced using carbon combustion synthesis of oxides (CCSO). In this process the exothermic oxidation of carbon generates a thermal reaction wave that propagates at a velocity of 0.1-3 mm/s through the solid reactant mixture of cobalt and iron oxides converting it to the cobalt ferrite without any external power consumption. This will enable a reduction in the production price of cobalt ferrite by minimization of the energy consumption. The combustion temperature can be set by proper choice of the amount of carbon added to the mixture of solid reactants. The extensive emission of CO₂ enhanced the porosity and friability of product. The as-synthesized ferrites had hard magnetic properties with coercivity 700 Oe and saturation magnetization up to 47 emu/g.