Experimental and Theoretical Realization of Morphology and Frequency Tuned Charge Transport Dynamics in Co-Zn Doped SrM Hexaferrite: Electrical, Impedance and Relaxation Realm

Abstract

The present report comprehensively investigates the influence of sol-gel synthesized cobalt and zinc-substituted SrFe12O19 on the morphological, structural, dielectric, and electrical characteristics. XRD analysis revealed that the substituents successfully replaced Fe3+ ions, leading to the existence of magneto-plumbite structure of M-type hexaferrite in all synthesized samples with some minor traces of CoFe2O4 in Sr Co 0.8 Zn 0.8 Fe 10.4 O 19 . With increasing the substitution level, SEM micrographs exhibited the formation of grain clusters. The electrical parameters had been investigated in the 20 Hz to 2 MHz frequency range. In the low-frequency region, both dielectric constant and loss tangent decreased with Co-Zn substitution. Sr Co 0.8 Zn 0.8 Fe 10.4 O 19 sample shows the minimum value of AC conductivity 3.95 × 10−5 Ω−1m−1 in the high-frequency region. Both the electric modulus and impedance spectra exhibit non-Debye behavior in all samples. The Cole-Cole plots ( M'' versus M' ) reveal the existence of a single semicircular arc in the x = 0.0 sample, caused by the grain boundary contribution.