Studies on magnetocapacitance, dielectric, ferroelectric, and magnetic properties of microwave sintered (1-x) (Ba0.8Sr0.2TiO3) - x (Co0.9Ni0.1Fe2O4) multiferroic composite

Present paper reports the synthesis of multiferroic composite (1-x) [Ba0.8Sr0.2Ti)O-3]-x[Co0.9Ni0.1Fe2O4] were x = 0.1, 0.2, 0.3 and 0.4. Both phases of the composite i.e. ferroelectric (BST) and ferrite (CNFO) are synthesized via hydroxide co-precipitation method followed by microwave sintering technique at 1100 degrees C. These composites were characterized for their structural, microstructural, dielectric analysis, magnetodielectric (MD) effect and ferroelectric properties. Presence of both the phases ferroelectric (BST) and ferromagnetic (CNFO) are confirmed by the x-ray diffraction and scanning electron microscopic analysis. Maxwell-Wagner type dielectric dispersion is observed in frequency dependent dielectric measurement. Temperature-dependent dielectric properties were measured from 25 degrees C to 500 degrees C at various applied frequencies. Ferroelectric behavior in the composites was confirmed by the polarization vs. Electric field analysis. The magnetodielectric effect was studied in the presence of applied magnetic field from 0 to 1 Tesla. Magnetocapacitance (%) increases with increase in the ferrite concentration in the ferroelectric phase. The maximum percentage of magnetocapacitance is observed in 60BST-40CNFO composite which is MC = 30% at the frequency 1 KHz with the applied magnetic field is 1-Tesla. Room temperature magnetic hysteresis loops show an increase in saturation magnetization (Ms) with an increase in ferrite concentration.