Dielectric relaxation behavior in co-precipitation derived ferrite (Zn1−xNix)Fe2O4 (0.2 ≤ x ≤ 0.5) ceramics

The influence of nickel doping on the electrical properties and dielectric relaxation in Zn1−xNixFe2O4 (ZNFO, 0.2 ≤ x ≤ 0.5) ceramics has been investigated via the dielectric and complex impedance spectra measurements. According to the modified Curie–Weiss law, the diffusivity factor of the ZNFO ceramics from 1.69 to 2.02 with x increasing from 0.2 to 0.5, respectively. Two relaxation peaks are observed in the nickel doped samples, by employing the modified Arrhenius equation, two activation energy values of different sintering temperatures were calculated and analyzed in combination with oxygen vacancy. The Cole–Cole plots showed that the semicircular arcs which are nonideal Debye type, and the grain boundaries resistance increases with increasing Ni concentration.