Preparation and characterization of MnFe2O4 by a microwave-assisted oxidative roasting process

An innovative and effective technological process is proposed to synthetize spinel manganese ferrite (MnFe2O4) by a microwave-assisted oxidization roasting process. In the current paper, the effect of operating variables on the formation mechanism of Fe-MnO systems for synthesizing spinel MnFe2O4 is initially investigated to reveal the oxidation mechanism and phase transformation during the micro-wave-assisted oxidative roasting process. The synthetic MnFe2O4 microparticles with a saturation mag-netization (Ms) of 70.5 emu/g, a coercivity (Hc) of 4.65 Oe and a ratio of the saturation magnetization to remanent magnetization (Ms/Mr) of 0.055 were successfully prepared by heating for 30 min at 1000 degrees C in an air atmosphere. The MnFe2O4 samples exhibited normal and inverse spinel crystal structures, inevita-bly coexisting and co-transforming simultaneously at high temperature (>= 950 degrees C). Furthermore, this innovative and effective technological process can be extended to fabricate other spinel ferrite particles of interest. (c) 2023 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan. All rights reserved.