Optimizing optical, dielectric, structural, and electrical properties in Cu-substituted Mg-Zn ferrite nanoparticles: Insights for sustainable energy and environmental solutions

Abstract

The productive and straightforward strategy was developed to fabricate Cu-doped Mg-Zn ferrite nanoparticles (NPs) for enhancing electrical, optical, and structural properties, via the sol-gel auto-combustion technique. A series of ferrite compositions, Mg₀.₆Zn₀.₄Cu_xFe₂₋ₓO₄ (x = 0, 0.2, 0.4, 0.6, and 0.8), were systematically analyzed using X-ray diffraction (XRD), UV–visible spectroscopy (UV-Vis), Fourier-transform infrared spectroscopy (FTIR), LCR meter, current-voltage (I-V) measurements, and scanning electron microscopy (SEM). XRD analysis confirmed the formation of a single-phase spinel cubic structure in all synthesized samples, with a minimum crystallite size of 41.39 nm and a lattice constant of approximately 8.36 Å. Optical characterization using UV-Vis spectroscopy revealed an increase in optical bandgap energy from 1.22 eV to 1.51 eV as Cu²⁺ content increased. FTIR analysis identified the tetrahedral (A) band within the range of 712.81–721.96 cm⁻¹, and the octahedral (Β) band within the range of 654.02–657.80 cm⁻¹ in the spinel structure, confirming the presence of ferrite bonding. Morphological investigations through SEM micrographs demonstrated a reduction in agglomeration, leading to improved particle dispersion within the crystal structure. Electrical characterization through I-V measurements affirmed the semiconducting behaviour of the synthesized ferrite nanoparticles. Additionally, dielectric studies indicated that AC conductivity increased at higher frequencies, while dielectric loss, dielectric constant, and loss tangent decreased with Cu²⁺ substitution. The combined findings suggest that by leveraging their magnetic, optical, and electrical properties, Cu-doped Mg-Zn ferrite nanoparticles can significantly contribute to sustainable energy solutions, environmental protection, next-generation electronic devices, water treatment, filtration, and conservation systems and hence contribute to the global efforts of water conservation and responsible water management.