Structural, magnetic, and electrical properties of Nd-substituted cobalt ferrite

CoNd_xFe_2-xO₄ (0 ≤ x ≤ 0.2) ferrite material with spinel structure was successfully synthesized by the sol–gel self-propagating method. The microstructure and electromagnetic properties of Nd-substituted cobalt ferrite were studied. The study found that the substitution of Nd³⁺ for Fe³⁺ at the B site of ferrite changed the electromagnetic properties of the cobalt ferrite. Among them, when the doping amount x ≥ 0.05, the second-phase NdFeO₃ will be formed. The lattice constant of cobalt ferrite after Nd³⁺ substitution first increases and then reduces. The saturation magnetization of CoNd_xFe_2-xO₄ ferrite exhibits a linear downward trend and coercivity shows an overall upward trend. In addition, the dielectric constant (ε´) has raised from 36.15 (x = 0.00) to 336.9 (x = 0.05). When the substitution amount x = 0.05, the cobalt ferrite has good electromagnetic properties, i.e., Ms = 90.3 emu/g, Hc = 197.2 Oe, and ε´ = 336.9. Generally speaking, the substitution of Nd can enhance the electromagnetic properties of cobalt ferrite, which provides reference for obtaining high-performance ferrite by rare earth ions substitution.