Improvement of Magnetic and Dielectric Properties Through Cd Substitution in Mg–Ni Spinel Ferrite

This study aims to improve the magnetic and dielectric properties of Ni–Mg ferrites by incorporating cadmium. Ni_0.6−xCd_xMg_0.4Fe₂O₄ crystals were synthesized using the sol–gel method, with doping ratios (x) ranging from 0.00 to 0.40. XRD analysis confirmed the primary cubic phase formation (space group Fd \(\overline{3}\) $\overline{3}$ m), with Ni_0.6−xCd_xMg_0.4Fe₂O₄ crystallite sizes ranging from 34 to 23 nm. Cationic distribution analysis revealed slight changes in ionic radii angles due to doping, influenced by the difference between Ni (0.69 Å) and Cd (0.95 Å) radii. Cd²⁺ concentration significantly impacted lattice constant, density and dislocation density. Increasing Cd concentration increased saturation magnetization in VSM measurements, while coercivity and remnant magnetization decreased.