We report on the preparation and transport properties of Gadolinium substituted Ni (1-x) Zn x Gd y Fe (2-y) O 4 (0⩽x⩽1,y=0.1) nano particles using low temperature citrate precursor combustion method. The Rietveld refinement of PXRD data suggests the crystal structure of sample belongs to Fd-3m space group with an octahedral occupation of Gd +3 ions. FESEM micrographs show the existence of porosity in the samples. The dielectric studies reveal the good dielectric behaviour with high dielectric constant in Zn +2 substituted sample (x = 0.4). An increase in a.c conductivity observed in the Zn +2 substituted sample due to the hopping mechanism. The impedance spectroscopy of the samples shows the existence of high grain boundary resistance and an alternate switching of dielectric relaxation from non-Debye to Debye type. The activation energies and Curie temperature estimated using D. C. conductivity measurements drop linearly with an increase in Zn +2 concentration. We attribute the observed transport properties mainly to the hopping of Fe +2 ↔ Fe +3 ions.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics