Comparative studies of the dielectric properties of (1−x)BiFeO₃-xNi_0.8Zn_0.2Fe₂O₄ (x=0.0, 0.2, 0.5, 0.8, 1.0) multiferroic nanocomposite with their single phase BiFeO₃ and Ni_0.8Zn_0.2Fe₂O₄

BiFeO₃ (BFO) and nickel zinc ferrite Ni_0.8Zn_0.2Fe₂O₄ (NZFO) were prepared by sol gel and auto combustion route respectively. Stoichiometric proportions were mixed to obtain the multiferroic nanocomposites having the compositional formula (1−x)BiFeO₃-x Ni_0.8Zn_0.2Fe₂O₄ (x=0.0, 0.2, 0.5, 0.8, 1.0). The phases were confirmed by XRD analyses. SEM micrographs showed the agglomerated nature of the particles with continuous grain growth in all directions. Elemental compositions were confirmed from EDAX studies. FTIR studies showed the stretching and bending vibrations of the various bonds present in the samples. The dielectric properties such as dielectric constant, ε′ and dielectric loss tangent, tanδ were studied for the spinel, perovskite and nanocomposite ferrites. Experimental result shows an increasing trend in the value of dielectric constant in going from spinel to perovskite phase. The frequency dependence of tanδ showed minimum loss for x=0.5 nanocomposite. Possible mechanisms explaining the above results were being discussed.