Dielectric and magnetic properties of high porous Gd ⁺³ substituted nickel zinc ferrite nanoparticles

Wereport on the synthesis and characterization of Gd ⁺³ substituted Ni-Zn nano ferrites (Ni _0.6 Zn _0.4 Gd _y Fe _2−y O ₄ ;y = 0,0.1,0.15, and 0.2) via low-temperature citrate gel auto-combustion method. The structural studies carried out by PXRDrevealed a decrease in the lattice constant and crystallite sizes upon ^Gd+3 substitution with low concentration but increases with further increase in the concentration. Wefound the porosity of the samples decreases linearly as a function of ^Gd+3 concentrations. Well defined spherical grainswith a higher porosity of the samples are confirmed by FESE Manalysis. With an increase in the ^Gd+3 concentrations, the dielectric constant increased up to five folds in the magnitude. The contribution of grain boundary and other factors on the electrical properties was revealed by impedance spectroscopy. The reduced remanence ratios showed in the magnetic hysteresis imply the charge in change in themagnetic properties upon the substitution of ^Gd+3 in the prepared ferrite.