Enhanced magneto-electric coupling and energy storage analysis in (BiFeO₃–BaTiO₃)/CoFe₂O₄ composites

Enhanced magneto-electric coupling and energy storage density analysis of solid-state route derived (BiFeO₃–BaTiO₃)/CoFe₂O₄ composites were investigated for memory application under the variation of the magnetic phase of CoFe₂O₄. The powder X-ray diffraction data, SEM–EDX, Raman spectroscopy, and FTIR measurements were carried out to investigate the crystalline structure, composite formation and phase purity of all the samples. Magnetic measurements showed very high magnetization values obtained from 0.063 emu/g for 0.7BF–0.3BT to 18.14 emu/g for (0.7BF–0.3BT)/30CF composite near room temperature. The weak but countable maximum ferroelectric polarization (P_max) was achieved due to the change in the area of the loops with the variation of frequencies from 50 to 200 Hz. The highest value of energy storage density (J_u) and efficiency (η) for (BF–BT)/30CF (J_u = 37.08 mJ/cm³ and η = 89.40%) composite was achieved. The dielectric anomaly near the magnetic transition temperature (T_c ~ 425 °C) and the variation in the maximum polarization values from 4.63 to 6.6 µC/cm² with respect to the applied magnetic field confirmed the strong evidence of magneto-electric coupling in (BF–BT)/CF composite samples. The highest values of magneto-electric coefficients (α) were achieved 9.039 mV/cm Oe at 600 Oe, 9.039 mV/cm Oe at 1100 Oe and 22.59 mV/cm Oe at 1600 Oe for (BF–BT)/10CF, (BF–BT)/20CF and (BF–BT)/30CF composites respectively.