Effects of Zinc Substitution on the Microstructural and Magnetic Characteristics of Cubic Symmetry Nickel Ferrite System

Abstract

The preparation of ZnxNi1−xFe2O4 (x = 0 and 0.3) nanoparticles using glycine-mediated combustion route was successfully completed depending on the zwitterion and combustion characteristics of glycine. Using a variety of methods, including XRD, FTIR, SEM/EDX, and TEM, the investigated ferrites were characterized. XRD and FTIR analyses confirm that Zn0.3Ni0.7Fe2O4 and NiFe2O4 nanoparticles crystallize in the cubic symmetry in the space group Fd3m. An increase in the lattice parameters and a subsequent decrease in crystallite size were caused by the process of replacing Ni ions with Zn ions. In accordance with Waldron’s hypothesis, FTIR spectra demonstrate that the ferrites have a spinel-type structure as they are produced. The substitution process by Zn led to different changes in the half band widths with subsequent in splitting in the absorption band around 400 cm−1. The examined ferrites’ cation distribution showed that Zn2+ and Ni2+ ions favored the tetrahedral (A) and octahedral (B) sites, respectively, while Fe3+ ions occupied both A- and B-sites, providing mixed spinel ferrite. TEM analysis indicates the formation of spinel nanocrystalline particles with low agglomerations. The particle size of the as-synthesized ferrites did not exceed 16 nm. By applying the VSM approach at room temperature, the magnetic characteristics of the ferrites under investigation were established. The magnetization of Zn0.3Ni0.7Fe2O4 nanoparticles was found to be higher than that of NiFe2O4 nanoparticles according to the magnetic data. Increasing the magnetization and the experimental magnetic moment of Zn0.3Ni0.7Fe2O4 were accompanied by a decreasing of its coercivity. The net magnetization is oriented along different high symmetry directions. On the other hand, the anisotropy of the nickel ferrite increases by substituting Ni with a Zn ion.