X-ray diffraction and Mossbauer studies of phase transformation in manganese ferrite prepared by combustion synthesis method

Mixed ferrite MnFe2O4 has been prepared by combustion synthesis method and subsequent heat treatment. The effects of annealing temperature and quenching conditions on phase compositions of the samples have been investigated by X-ray diffraction and Mossbauer spectroscopy. The results show that the combustion of Fe2O3, MnO2 and Fe results in a series of mixtures of new phases, which convert to MnFe2O4 single spinel phase during subsequent heat treatment at 1200 degreesC for 2 h and rapid quenching. Moreover, combustion synthesis of MnFe2O4 can efficiently induce a redistribution of divalent and trivalent ions in the A and B sites. (C) 2004 Elsevier B.V. All rights reserved.