Synthesis and magnetic properties of zinc ferrite from mechanochemical and thermal treatments of Zn-Fe3O4 mixtures

The preparation of ZnFe2O4 from mechanochemically activated reactive mixtures Zn-Fe3O4 is studied. The physicochemical and structural evolution of the system is analyzed by X-ray diffraction, vibrating sample magnetometry, differential thermal analysis and scanning electron microscopy. The activated mixtures reacted towards the formation of ZnFe2O4 at lower temperatures than the non-activated ones. In addition, thermal treatments as a function of time revealed a non-expected magnetic behavior of some mixtures. In order to interpret this observation, a qualitative diffusional reaction model is proposed. (C) 2003 Elsevier B.V. All rights reserved.