Structure, Microstructure, Magnetic, Electromagnetic, and Dielectric Properties of Nanostructured Mn-Zn Ferrite Synthesized by Microwave-Induced Urea-Nitrate Process

In this work, the effect of urea-to-nitrate molar ratio on the synthesis and properties of Mn0.5Zn0.5Fe2O4 ferrite prepared by microwave-induced combustion method has been studied. The product powders synthesized at three different molar ratios of urea to nitrate (U/N ratio), varying from 0.58 to 1.08. X-ray diffraction patterns confirm formation of a spinel-type structure of ferrite and also hematite in the as-synthesized powders. The average of particle size is found to be in the range 30-80 nm. The values of saturation magnetization and permeability are increased with the increase in U/N ratio. Dielectric parameters were measured as a function of frequency. The real and imaginary parts of dielectric constant are found to decrease with the increase in frequency, while the ac conductivity is found to increase with increasing frequency. The complex impedance analysis shows only one semicircle indicating the predominant effect of grain boundary property of the material.