Optimization of magnetoelectric coupling in BiFeO3-BaTiO3-MnFe2O4 tri-phase composites for ultra-sensitive devices

Abstract

Multiferroic materials with coupled electric and magnetic orderings have astonished the scientific community by exhibiting magnetoelectric (ME) coupling, viable for multistate memory devices. Facile synthesis of multiferroic composites have further triggered these delightful attributes. Here we present a series of tri-phase composites of the form; (1–x)(0.7BiFeO3 + 0.3BaTiO3) + xMnFe2O4, synthesized by a facile two-step method. The phase-pure synthesis was confirmed using X-ray diffraction. For energy storage capability, a composition with x = 0.02, reveals the recoverable energy density of ∼0.22 mJ/cm3 followed by the highest efficiency of 64.02%, making such composition favourable for energy storage perspectives at minute inclusion of the spinel phase. The characteristic I-V curves were used to explain the leakage current of BiFeO3 (BFO). The positive up and negative down (PUND) sequence demonstrates the significant variation in switching charge density. The gradual increase in grain size resulted in a lowering of the coercivity values up to 301 Oe at x = 0.10 having 6.31 emu/g as saturation magnetization (MS) value along with MR/MS ratio of 0.33. The linear response shown by ME coupling at x = 0.06 along with the afore mentioned attributes make this composition a potential candidate for ultra-sensitive magnetoelectric devices.