Enhanced dielectric permittivity on yttrium doped cobalt ferrite nanoparticles

Abstract

Nanoparticles (NPs) of CoYxFe2 xO4 (06 x 0:04) were synthesized by combustion reaction method in order to study the effect of Y3þ ions (x) on the dielectric properties. It was found that the relative dielectric permittivity (e0 ) measured in a broad range frequency 100–2 MHz at room temperature. e0 increases with the Y3þ ions concentration and decreased with frequency, being 200 (83), and 998 (320) at 100 Hz (1KHz) for x ¼ 0 and x ¼ 0:04, respectively. The experimental data could be fitted to the Cole–Cole model and the relaxation time (s) was found to increase with Y3þ ions concentration. The results were discussed in the terms of space charge polarization and ions distribution over tetrahedral A-site and octahedral Bsites of the spinel structure and cation vacancies due to the presence of Y3þ ions in the spinel structure of cobalt ferrites.