Effectively coupled BiFeO3-MnFe2O4-Cr2O3 tri-phase multiferroic composites for efficient energy storage and fast switching

Abstract

Owing to several unique features, multiferroic materials and their composites are gaining significance in microelectronic and spintronic based devices. In particular, the magnetic and electric orders of these materials can effectively be tuned and their reciprocal control is also feasible. In this context, this work presents a series of 0.8[(1–x)BiFeO3 + xMnFe2O4] + 0.2Cr2O3 nanocomposites, synthesized by sol–gel auto-combustion and solid state ball milling routes. The diffraction analysis confirmed the required crystalline phases. The precise crystallite size was calculated using Scherrer's equation and a compared with the sizes obtained with the Williamson-Hall plots. Energy dispersive X-ray spectroscopy confirmed the presence of all the required stoichiometric elements in agreement with empirical formulae. A gradual increase in the average grain size was observed using microscopic images. The rising gap between recovered energy and energy loss, noted at optimized spinel phase contents, make these composites potential choice for the efficient energy storage devices. At 'x = 0.4,' the greatest value of energy density efficiency ∼ 68.4%, was recorded. The I-V analysis indicated that all of the samples had a current barrier. The switching charge density was enhanced with the substitution of spinel phase, confirmed from PUND data. Magnetic analysis revealed that saturation magnetization of in the composite series increased from 0.85 to 55.5 emu/g and coercivity decreased from 170 to 90 Oe, whereas the remanent magnetization increased from 0.15 to 4.5 emu/g. Such findings demonstrated the applications of prepared samples in a variety of ways including energy and data storage devices.