Influence of the Synthesis Process on the Physical Property Characteristics of BiFeO3 Ceramics Prepared by Flux-based Molten Salt and Solid-state Reaction Route: A Comparative Study

Abstract

This work reports the influence of the solid-state reaction (SSR) and molten-salt synthesis (MSS) routes on the physical properties of the multiferroic BiFeO3 (BFO) compound exploited for capacitors and memory devices. Rietveld refinement reveals that the MSS-derived BFO ceramics have exhibited a pure-phase distorted rhombohedral perovskite structure at low temperatures (650 °C) compared to the SSR method. The FE-SEM illustrates the uniform distribution of spherical-shaped BFO grains. By altering the fabrication route, the calculated bandgap values of BFO were tuned within the range of (2.14 ± 0.02) to (2.05 ± 0.02) eV based on Tauc’s plot. The suppression of oxygen vacancies led to better dielectric characteristics at higher frequencies in the MSS-prepared BFO nanoceramics. Also, the MSS-derived BFO ceramics possessed a typical canted-AFM loop with a higher MR value of ∼2.73×10−2 emu g−1. These observations suggest that fabrication techniques have a decisive effect on the phase formation kinetics and multiferroic properties of BFO ceramics.