Mechanochemical synthesis of stoichiometric MgFe2O4 spinel

Abstract

The influence of long-term milling of a mixture of (1) MgO and α-Fe2O3, (2) MgCO3, and α-Fe2O3, and (3) Mg(OH)2 and α-Fe2O3 powders in a planetary ball mill on the reaction synthesis of nanosized MgFe2O4 ferrites was studied. Mechanochemical reaction leading to formation of the MgFe2O4 spinel phase was followed by electron microscopy, (SEM and TEM), X-ray diffraction and magnetization measurements. The spinel phase was observed first in cases (1) and (2) after 5 h of milling, and its formation was observed in all cases after 10 h. The synthesized MgFe2O4 ferrite has a nanocrystalline structure with a crystallite size of about 11, 10, and 12 nm, respectively for cases (1)–(3). Magnetic measurements after 10 h of milling show magnetization values of 19.8 J/(Tkg), 23.5 J/(Tkg) and 13.8 J/(Tkg), respectively for the cases (1)–(3).