Structural, morphological and magnetic properties of nano-crystalline zinc substituted cobalt ferrite system

Nano-crystalline zinc-substituted cobalt ferrite powders, Co1−xZnxFe2O4 (x = 0, 0.25, 0.5, 0.75 and 1), have been synthesized by the combustion route. The structural, morphological and magnetic properties of the products were determined and characterized in detail by X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive X-ray spectroscopy (EDX) and vibrating sample magnetometer (VSM). X-ray analysis showed that the samples were cubic spinel. The increase in zinc concentration resulted in an increase in the lattice constant, unit cell volume, X-ray density, ionic radii, the distance between the magnetic ions and bond lengths on tetrahedral sites and octahedral sites of cubic spinel structure. Opposite behavior was observed for the average crystallite size of the as synthesized solids. The variation of saturation magnetization (Ms) value of the samples was studied. The maximum saturation magnetization value of the Coo.25Zn0.75Fe2O4 sample reached 76.87 emu/g. The high saturation magnetization of these samples suggests that this method is suitable for preparing high-quality nano-crystalline magnetic ferrites for practical applications.

► Nano-magnetic Zn substituted cobalt ferrites have been prepared using combustion route with best magnetic properties. ► The magnetism of Co-ferrite was less than that of Zn-ferrite. ► Zn substitution process resulted in significant changes in the structural and morphological properties of ferrites produced. ► The lattice parameters of cubic spinal structure were found to increase with the increase in zinc concentration.