Grain Size and Grain Boundary Effect on Dielectric Behavior of Nanocrystalline Cobalt ferrite

Nanocrystalline cobalt ferrite (CoFe2O4) was prepared by the Sol-gel method. Different crystallite sizes CoFe2O4 were obtained by high energy planetary ball milling technique by varying the time of milling. Crystal structure and dielectric properties were studied as a function of grain size and grain boundary. The structural characterization has been carried out by using the X-ray diffraction (XRD) technique. Phase purity, crystal structure and average crystallite size have been studied by analyzing the XRD pattern. The dielectric of all the samples has been characterized by impedance analyzer. The increase in dielectric constant has been observed with increasing grain boundaries in the material, i.e. with the decrease in grain size.