Magneto-structural properties of Mg-substituted copper ferrite nanoparticles

Abstract

This study explores the synthesis and characterization of magnesium-substituted copper ferrite (Mg _x Cu _1-x Fe _2 O _4 , 0.0≤x≤1.0) nanoparticles using the polymer-assisted sol–gel self-combustion method. The effects of magnesium substitution on the structural, elastic, and magnetic properties of the ferrites were systematically investigated. X-ray diffraction (XRD) analysis confirmed the formation of single-phase cubic spinel structures with particle sizes ranging from 8–21 nm. A slight increases in the lattice parameter was observed with higher magnesium content, attributed to the substitution of smaller Cu ^2+ ions with slightly larger Mg ^2+ ions. Fourier Transform Infrared (FTIR) spectroscopy and Mössbauer spectroscopy revealed the spinel structure and complex magnetic interactions between ferromagnetic and superparamagnetic phases. The spin canting was observed and found to vary significantly across compositions, with a maximum canting angle of 58.47°. This notable result highlights the important magnetic behavior of these materials. The saturation magnetization (M _S ) varied across samples, with the x = 0.6 composition exhibiting optimal magnetic performance. Cation distribution analysis using XRD, Mössbauer spectroscopy, and magnetic measurements consistently showed the redistribution of cations between the tetrahedral (A) and octahedral (B) sites in the spinel structure. This research demonstrates the potential of magnesium-substituted copper ferrites for magnetic applications, with notable improvements in magnetic and structural properties due to cation substitution.

Keywords

• ferrite
• nanoparticles
• superparamagnetism
• mössbauer studies
• spin canting