Studies of structural, dielectric, and optical properties of CuCoFeO4 spinel for high frequency, microwave, and optoelectronic applications

Abstract

In this study, we synthesized by the sol-gel method the CuCoFeO4 spinel and studied its structural, dielectric, and optical properties. The sample exhibits a regular cubic spinel structure (Fd3¯m space group). Semiconductor behavior with the CBH model was observed from the variation in electrical conductivity as a function of frequency and temperature. Summerfield scaling merges conductivity isotherms into a single master curve. Non-Debye relaxation is shown in the electric modulus of the prepared composition. The impedance spectra indicate the effects of both grain and grain boundary contributions on electrical properties. The impedance analysis is presented with electrical processes modeling in the sample. This is done using an equivalent circuit model comprising a parallel RC circuit for grains and grain boundaries. The obtained simulated results agree with the measured results. Maxwell-interfacial Wagner's polarization theory was used to explain dielectric constant change. The synthesized material exhibits low dielectric constants and dielectric losses at higher frequencies, as well as high electrical resistivity. These properties make CuCoFeO4 spinel a suitable candidate for high-frequency applications and microwave absorption devices. Moreover, CuCoFeO4 spinel presents low band gap energy, making it a suitable material for visible-light absorption.