Magnetic and Structural Investigations of Nanocrystalline Cobalt-Ferrite

Abstract

Cobalt ferrite is an important magnetic material due to their large magneto-crystalline anisotropy, high <br />cohercivity, moderate saturation magnetization and chemical stability.In this study, cobalt ferrites <br />Nanoparticles have been synthesized by the co-precipitation method and a new microemulsion route. We <br />examined the cation occupancy in the spinel structure based on the “Rietveld with energies" method. The Xray <br />measurements revealed the production of a broad single ferrite cubic phase with the average particle <br />sizes of about 12 nm and 7nm, for co-precipitation and micro-emulsion methods, respectively. The FTIR <br />measurements between 400 and 4000 cm-1 confirmed the intrinsic cation vibrations of the spinelstructure for <br />the two methods. Furthermore, the Vibrating Sample Magnetometer (VSM) was carried out at room <br />temperature to study the structural and magnetic properties. The results revealed that by changing the method <br />from co-precipitation to the reverse micelle the material exhibits a softer magnetic behavior in such a way <br />that both saturation magnetization and coercivity decrease from 58 to 29 emu/g and from 286 to 25 Oe, <br />respectively.