ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Comparative investigation of structural, magnetic, and dielectric properties of Co_0.8Ni_xCu_0.2−XFe₂O₄ (x = 0.00, 0.10 and 0.20) soft magnet electroceramics

Fereshteh Mozardzadeh, Alireza Salehirad, and Sayed Ahmad Mozaffari

Department of Chemical Technologies, Iranian Research Organization for Science and Technology (IROST), Tehran, Iran

E-mail: salehirad@irost.ir

Received: 19 April 2025  Accepted: 20 August 2025

Abstract:

A series of soft magnetic electroceramics with the general formula Co_0.8Ni_xCu_0.2−xFe₂O₄ (x = 0.00, 0.10, and 0.20) were successfully synthesized via the sol–gel auto-combustion method, and their structural, morphological, magnetic, dielectric, and electrochemical properties were systematically investigated. X-ray diffraction confirmed the formation of a single-phase cubic spinel structure in all samples, while Fourier transform infrared (FTIR) spectroscopy further supported the presence of spinel-type bonds. Scanning electron microscopy revealed porous and agglomerated grain morphologies, and energy-dispersive X-ray (EDX) spectroscopy verified the elemental purity and stoichiometry of the synthesized ceramics. X-ray photoelectron spectroscopy was employed to analyze cation distribution and oxidation states within the spinel lattice. Magnetic properties were evaluated using a vibrating sample magnetometer, and dielectric behavior was examined using an LCR meter across the frequency range of 1 Hz to 10 MHz at room temperature. Electrochemical impedance spectroscopy measurements were performed using a potentiostat galvanostat equipped with a frequency response analyzer, providing insights into charge transfer and ion diffusion behavior. Among the studied compositions, Co_0.8Ni_0.1Cu_0.1Fe₂O₄ exhibited the most favorable combination of magnetic softness, high dielectric constant, low dielectric loss, and characteristic Warburg-type impedance response, indicating efficient ion transport and capacitive behavior. These results highlight its potential as a multifunctional electro ceramic material suitable for use in energy storage devices.

Graphical abstract

Keywords: Co0.8Ni0.1Cu0.1Fe2O4; Magnetic properties; Dielectric properties; Soft magnet; Electroceramic

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-025-04341-9

Chemical Papers 79 (12) 8633–8651 (2025)