Mössbauer Study of Ni-Zn Ferrites Obtained by the Self-Propagated Method

Abstract

Ni_1−xZn_xFe₂O₄ ferrites (x = 0, 0.5, 0.6 and 0.7) were prepared from self-propagated powders. Their structural and magnetic properties were characterised with x-ray diffraction, Mössbauer spectroscopy and ac susceptibility. Mössbauer analysis was performed at room temperature and at 15K, which was expected to yield useful information on the microstructure. The sintered samples present high initial permeability that increases as the concentration of Zn increases. The x= 0.7 Mössbauer spectrum exhibits superparamagnetism at room temperature and magnetic order at low temperature. The roles of cation-site occupation and magnetic coupling are discussed.