Preparation of MgFe₂O₄ nanoparticles by microemulsion method and their characterization

Abstract

This work presents the preparation and characterization of magnesium ferrite which is one of the important magnetic oxides with spinel structure. Magnesium ferrite was prepared via microemulsion method mediated hydrolytic decomposition of mixed alkoxide solutions. This microemulsion was using for preparation magnesium ferrit for the first time. The starting solution, composed from magnesium methoxide and iron ethoxide in dry ethanol, was introduced in to the prepared microemulsion and sequentially hydrolyzed by distilled water addition (Pithan et al. in J Cryst Growth 280:191–200, 2005; Shiratori et al. in J Eur Ceram Soc 25:2075–2079, 2005; Herrig and Hempelmann in Mater Lett 27:287–292, 1996). After raw powder precipitation, the samples were decantanted by ethanol and then calcined at temperatures 800, 900, 1,000 or 1,100 °C for 1 h. The resulting samples were characterized using powder X-ray diffraction, high resolution transmission electron microscopy, Mössbauer spectroscopy and magnetic measurements. X-ray diffraction and Mössbauer spectroscopy confirmed the presence of the spinel phase. The particles size was calculated from the XRD line broadening using Scherrer equation and their size was found about 31–38 nm, with only slight dependence on the heat treatment temperature. TEM revealed the particles size of about 39 nm. Magnetic measurements showed a ferrimagnetic behavior for all samples.