Study of dependence of magnetic properties on seeding temperature in fine particles of Cu_0·25Co_0·25Zn_0·5Fe₂O₄

摘要

Using a combination of X-ray diffraction, room temperature/low temperature Mössbauer studies and d.c. magnetization, the structural and magnetic properties of nano-sized Cu_0·25Co_0·25Zn_0·5Fe₂O₄, prepared using the coprecipitation method at different seeding temperatures, have been studied. Formation of α-Fe₂O₃ in these samples is observed to be very sensitive to the seeding temperature and is totally suppressed at a seeding temperature of 333 K. These results are explained in terms of the rate of coprecipitation of the different components as a function of temperature. Since α-Fe₂O₃ is antiferromagnetic, the presence and quantity of this impurity is also observed to deteriorate the overall magnetic properties of the spinel phase.