Gadolinium-Doped Nickel Ferrite (NiFe2O4) Nanoparticles: Structural, Optical, and Magnetic Characterization

Abstract

The study details the nickel ferrite nanoparticles (NiFe₂O₄) synthesized via the citrate gel auto combustion method doped with gadolinium and its characterization. The shape of synthesized powder is nearly spherical and exhibits a cubic spinel structure. Crystallite sizes of the synthesized powders are in the nano range. As the Gd concentration elevates, the lattice parameter expands while the crystallite size reduces. In spinel ferrites the tetrahedral and octahedral sites refer to two characteristic peaks and are revealed by the FTIR spectra. The synthesized powders resemble the presence of quantum confinement. Magnetic hysteresis measurements at room temperature suggest a reduction in saturation magnetization with Gd ion doping. The hysteresis loops of the experimental samples portray that these are soft magnets and associated squareness values are somewhat moderate. With an increasing Gd concentration, magnetization declines. The cation distribution on Fe⁺³ sites by Gd appears to be responsible for an overall decrease in magnetic moment.