Permeability and magnetic properties of Al3+ substituted Ni0.7Zn0.3Fe2O4 nanoparticles

In this work, the structural and magnetic properties of Al3+ substituted Ni-Zn ferrite powders were investigated. Ni0.7Zn0.3AlxFe2-xO4 (where x = 0.0-0.5) powders were obtained by sol-gel auto combustion method. X-ray diffractometer, vibrating sample magnetometer, scanning electron microscopy, infrared spectroscopy, and permeability were used to study the effects of Al3+ ions on the structural and magnetic properties. X-ray patterns reveal that all the samples have single-phase cubic spinel structure. Infrared spectroscopy was used to locate the absorption bands and to study the influence of Al3+ substitution on the spinel structure of the presently investigated system. The lattice constant and x-ray density were calculated from the XRD data. The density of the samples was measured and consequently the porosity was calculated too. Magnetic properties were carried out by means of magnetization measurement to study the magnetic interaction between the ions. This paper is also focused its discussion on the dependence of the permeability spectra with the frequency variation. The permeability and Curie temperature were determined using the temperature dependent permeability measurements. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4748959]