Studies on electrical properties of Fe doped ZnO nanostructured oxides synthesized by sol–gel method

Abstract

We report the results of the studies on electrical properties of Zn1–xFexO (x = 0.10, 0.15 and 0.20) nanoparticles synthesized using sol–gel method. X–ray diffraction (XRD) measurement confirms the presence of extra phase of ZnFe2O4 in all the samples which gets enhanced with increase in Fe concentration. Surface morphological studies using atomic force microscopy (AFM) suggest the reduction in grain size with increase in Fe doping level in ZnO. All the dielectric parameters show dispersion nature and dielectric constant has been found to increase with Fe content. The obtained dielectric behavior has been understood on the basis of Maxwell–Wagner (M − W) mechanism and Koop's theory. Frequency dependent electrical conductivity has been understood on the basis of Jonscher's universal power law that suggests a conduction of charge carrier through correlated barrier hopping (CBH) mechanism. Impedance spectroscopy measurements have been explained on the basis of crystal cores and crystal boundary density. Grain boundary contribution in conduction mechanism is identified by fitting equivalent circuit model on cole–cole plots. Temperature and magnetic field dependent variation in electrical properties of studied samples has been understood on the basis of structure–property correlations.