Characterization of microstructure and magnetic properties for Co2+ ions doped MgFe2O4 spinel ferrites

The purpose is to investigate the crystal structure and magnetic properties of MgFe2O4 ferrites with divalent Co2+ cations substitute in CoxMg1-xFe2O4 (x = 0.0, 0.2, 0.5, 0.8, and 1.0) successfully synthesized using standard ceramic technology. The crystal structure, valence state distribution, functional groups, ion occupancy rate and magnetic properties were systematically investigated, revealing that the changes in magnetic properties are closely related to the microstructure. All samples were characterized by XRD as a pure spinel structure with space group Fd-3m. The intrinsic coercivity (H-c), saturation magnetization (M-s) and core loss (P-cv) performance of Co2+ ions doped MgFe2O4 ferrites were significantly optimized under the appropriate doping level. H-c and M-s continuously strengthen in the range of 0 <= x <= 1 at 300 K, where the maximum saturation magnetization (M-s) reaches 102.0 emu/g and the maximum intrinsic coercive force reaches 253.9 Oe. Besides, compared with x = 1, the sample obtained the lowest core loss and comparatively high magnetic susceptibility at x = 0.8. Simultaneously, the saturation magnetization and coercivity at 300 K are 76.5 emu/g and 184.7 Oe, respectively. Comprehensive experimental results show that the sample possesses a wider range of application when the doping amount x = 0.8.