Structural, morphological, optical, magnetic and dielectric properties of Ni_1−xZn_xFe₂O₄ (x = 0 − 1) nanoparticles

Ni_1−xZn_xFe₂O₄ (x = 0.0, 0.25, 0.5, 0.75, 1.0) nanoparticles (NPs) are prepared by solution combustion method. The presence of zinc ions causes considerable changes in the structural and magnetic properties of the NiFe₂O₄. The structural, morphological and magnetic properties of the samples are characterized by X-ray diffraction (XRD), Scanning Electron Microscopy, and Vibrating sample magnetometer. The average particle size of the powder is determined from XRD. It confirms the nanosized dimension of the NPs in the size range of 60–70 nm. The Zn²⁺ content has a significant influence on the dielectric properties of sintered Ni_1−xZn_xFe₂O₄ samples, such as dielectric constant (k) and dielectric loss tangent (δ). These values decrease with increasing zinc content. The saturation magnetization and the experimental magnetic moment are observed to initially increase (up to x = 0.25), and then continuously decrease with further increase in Zn content x. This decreasing trend obeys the three-sub lattice model suggested by Yafet–Kittel (Y–K). The Y–K angle for the NiFe₂O₄ NPs increases gradually with increasing Zn concentration.