Synthesis of Spinel Nanocrystalline ZnFe2O4: Structural, Optical, Magnetic and Electrical properties.

Abstract The present paper deals with the synthesis of Zinc Ferrite (ZnFe2O4) nanoparticles using simple, low cost co - precipitation method and study the structural, optical, magnetic and electrical properties. The samples have been prepared at two different calcination temperatures of 400˚ C and 600˚ C. The XRD studies indicate that the synthesized ZnFe2O4 samples exhibit cubic spinel structure and that the grain size increases with calcination temperature. The FTIR spectra demonstrate bands associated with metal – oxygen bonds in the tetrahedral and octahedral sites. Moreover, no unwanted impurity such as nitrate has been detected in the synthesized samples revealing their high purity. The micro structural analysis shows that though most particles are irregular granular ones, some are spherical. The optical band gap energy is found to increase with increasing calcination temperature. The Vibrating Sample Magnetometer (VSM) studies reveal the super paramagnetic behavior of the synthesized samples, even for a high Fe: Zn ratio of 1:2. The electrical resistivity of the samples decreases with increase in calcination temperature.This phenomenon has been explained on the basis of the Verwey-de Boer mechanism.