OICC Press International Nano Letters 2228-5326 12 2 (June 2022) 2022 01 06 Dynamics of complex impedance, dielectric and electric modulus for NiCuZn ferrites with theoretical justification 10.1007/s40089-021-00363-9 EN M. Faishal Mahmood Department of Physics, Chittagong University of Engineering and Technology, Chattogram, BD M. Belal Hossen Department of Physics, Chittagong University of Engineering and Technology, Chattogram, BD Journal Article 2022 01 06 Abstract Ni 0.80-x Cu 0.20 Zn x Fe 2 O 4 (step size 0.05) with titular compiled chemical of various spinel ferrites have been synthesized through auto-combustion and characterized through X-ray diffraction for structural analysis which showed 43 to 46 nm distributed cubic spinel. The effect of Zn 2+ substitutions to dilute the NiCuZn ferrites has been studied with electrical modulus analysis and impedance measurements within the frequency range from 20 to 5 MHz. Besides semicircular arc tendency, two-layer leaky capacitor model is indicated by the complex impedance spectroscopy at lower- and higher-frequency ranges. Non-Debye type relaxation has been revealed clearly in the electric modulus spectra. Non-Debye type dielectric nature is found in the dielectric spectrum and checked by the Non-modified Debye equation. The AC conductivity spectrum is found in increasing order and justified by theoretical Jonscher Power Law. The Cole–Cole plots confirm the single semicircles for grain boundary contribution at the lower-frequency zone, which is further justified by the theoretical model. The role of Zn in modifying nanostructure and impedance spectra of these ferrites has been explained.