Magnetic and Structural Properties of Nanocrystalline Cobalt-Substituted Magnesium-Manganese Ferrite

A series of Mg0.5Mn0.5Fe2-xCoxO4 (0 <= x <= 0.5) samples were synthesized by citrate precursor method. The impact of replacing Fe ions by Co on the structural parameters and magnetic properties of the system was investigated utilizing X-ray diffraction and M-H magnetic measurements at room and low temperatures. Phase analysis revealed a single-phase spinel for all samples, and cation distribution was suggested using data of magnetization loops, Rietveld analysis and then confirmed by Bertaut method. Both saturation magnetization and coercivity increase with Co content up to x = 0.3, then decrease slightly. The variation of lattice parameter, the interatomic distances, and the bond angles upon increasing the Co content was determined and then correlated with cation distribution and the magnetic behavior.