Combustion synthesis and magnetic characterizations of Mn substituted Ni-Zn ferrite nanoparticles

摘要

The ferrite samples with a general formula Ni_(0.6-x)Mn_xZn_(0.4)Fe_2O_4 (where x = 0.0-0.6 in steps of x = 0.2) were synthesized by sol-gel auto combustion method using nitrates of respective metal ions. The synthesized samples were annealed at 600 0C for 4 h. The phase purity of the samples was investigated by X-ray diffraction technique. Nano size of the particle was confirmed by TEM measurement. An analysis of X-ray diffraction patterns reveals the formation of single phase cubic spinel structure. The crystal lattice constant advances gradually with increasing x from 8.391 A to 8.451 A. Cation distribution of constituent ions shows linear dependence of Mn substitution. Based on the cation distribution obtained from XRD data, structural parameters such as lattice parameters, ionic radii of available sites and the oxygen parameter 'u' have been calculated. An initial increase followed by a subsequent decrease of saturation magnetization with increase in x is observed.