Structural and Magnetic Behavior of MFe<sub>2</sub>O<sub>4</sub> Nanopowders for Water Treatment

Abstract

This study describes the sol-gel method's synthesis of ferrites [MFe2O4, M(II) = Co, Cu, Mg, Ni, and Zn]. The structure was studied by X-ray diffraction analysis. The surface morphology was studied using scanning electron microscopy (SEM), and the magnetic properties were studied using Mössbauer spectroscopy. The diffraction peaks at 30.1◦, 35.6◦, 43.2◦, 53.6◦, 57◦, and 62.6◦ can be attributed to Bragg reflections (2 2 0), (3 1 1), (4 0 0), (4 2 2), (5 1 1), and (4 4 0) planes confirm the formation of a cubic spinel structure of ferrite nanocrystals. The average size of magnesium ferrite crystallites calculated from the half-width of the most intense peak (3 1 1) was 25.96 ± 4.32 nm. Magnesium ferrite is a magnetically soft ferromagnetic powder with a predominance of the magnetite phase and relatively high magnetisation values. The magnitude of the hyperfine magnetic field for the studied nanoparticles is in the range of 440-490 kOe, which confirms the hypothesis that the analysed samples are particles of an iron-containing oxide with a disordered structure.