Effect of Annealing Time on the Cation Distribution in Mn Doped CoFe2O4

Abstract

In this work, the series of CoFe2-xMnxO4 powders were synthesized using the solid state method. The structure and lattice parameter of the samples were determined by the X-ray diffraction (XRD) and Rietveld refinement method. The morphology was confirmed without annealing and with annealing at 500°C for 4 and 100 h, with the samples examined by scanning electron microscopy (SEM). Then, the distribution of migrating cations was analyzed using X-ray absorption spectroscopy (XAS). Also, magnetic properties were examined by a vibrating sample magnetometer (VSM). It can be confirmed from the morphology that the average particle size before and after annealing remained unchanged, and ranged from 0.66 ± 0.20 μm to 0.79 ± 0.26 μm. Furthermore, the distribution of cations was no different after annealing Mn ions at 500°C for 100 h. However, the distribution of cations migrated to their site of preference after annealing Co and Fe ions in the structure. The result of migrations induced a saturated magnetization increase to 42.24 emu/g.