A study of nanosized Ni substituted Co–Zn ferrite prepared by coprecipitation

Nanoparticles of Ni0.25Co0.25Zn0.5Fe2O4 with different particle sizes were synthesized by chemical coprecipitation technique. The prepared nanoparticles were characterized and studied by X-ray diffraction, room temperature 57Fe Mössbauer spectroscopy and DC magnetization. Increase in annealing temperature leads to inversion of cations from their normal configurations which results in an increase in the hyperfine fields at both tetrahedral A and octahedral B sites. The decrease in saturation magnetization values with an increase in annealing temperature can be attributed to the variation in proportions of superparamagnetic phase and also the redistribution of cations in these ferrite nanoparticles. Variation of coercivity with annealing temperatures can be explained in terms of the size effect.