Electrical and dielectric properties of xNi0.53Cu0.12Zn0.35Fe1.88O4 + (1−x) BaTiO3 nanocomposites

The composite of xNi_0.53Cu_0.12Zn_0.35Fe_1.88O₄+ (1-x)BaTiO₃ were prepared by mixing nanocrystalline Ni_0.53Cu_0.12Zn_0.35Fe_1.88O₄ and BaTiO₃ powders at different weight percent.The powders were densified using microwave sintering method at 900°C/30 min. The phase and morphology\´ of the composites was observed with X-ray diffraction (XRD) and Scanning Electron Microscope (SEM). The frequency dependence of real (ε\´) and imaginary (ε") parts of permittivity was measured in the range of lMHz-1.8GHz. The values of ε\´ increases with an increase of BaTiO₃ content at 1MHz. The experimental value of dielectric constant was compared with available theoretical models. The transition temperature (T_c) of composite materials decreases with an increase of BaTiO₃ content.