Lattice strains and magnetic properties evolution of Ni doped rod-like cobalt-manganese ferrite

Co0.5Mn0.5-xNixFe2O4 (0.0≤x≤0.3) precursor is obtained by solvothermal method at 160 °C in glycol-water. Cubic Co0.5Mn0.5-xNixFe2O4 is obtained by calcining the precursor from 600 °C to 800 °C in air. The precursor and its calcined products are characterized by thermogravimetry and differential scanning calorimetry, X-ray powder diffraction, scanning electron microscopy, and vibrating sample magnetometer. A high-crystallized rod-like Co0.5Mn0.5-xNixFe2O4 with a cubic structure is obtained when the precursor is calcined at 800 °C in air for 2 h. Lattice parameters decrease with the increase of Ni2+ addition amount. The magnetic properties of Co0.5Mn0.5-xNixFe2O4 depend on Ni2+ doped amount and calcination temperature. Co0.5Mn0.3Ni0.2Fe2O4 obtained at 800 °C has the highest specific saturation magnetization value, 63.51 emu/g. However, Co0.5Mn0.3Ni0.2Fe2O4 obtained at 600 °C has the highest coercivity value, 1204.02 Oe.