Fine tuning of CoFe2O4 properties prepared by solution combustion synthesis

Abstract Single phase CoFe 2 O 4 powders were prepared by solution combustion synthesis using β-alanine as fuel. By adding to the reaction mixture various amounts of oxalic acid, which act as a retarding agent and pore generator, properties of CoFe 2 O 4 powders can be properly adjusted. Depending on the amount of oxalic acid, the average crystallite size of CoFe 2 O 4 ranges between 13 and 41 nm, whilst the specific surface area varies between 1.8 and 34.4 m 2 /g. The combustion synthesized CoFe 2 O 4 powders exhibit a hard ferimagnetic behavior. The CoFe 2 O 4 coercivity varies between 71.8 and 126.0 kA/m and the saturation magnetization ranges between 53.0 and 70.6 emu/g. After uniaxial pressing and sintering at 1400 °C for 4 h, the pellets reached relative densities up to 90% of the CoFe 2 O 4 theoretical density.