Mechanically assisted synthesis of multiferroic BiFeO3: Effect of synthesis parameters

We report the influence of synthesis parameters on the crystal structure and the electronic and magnetic behavior of multiferroic bismuth ferrites, BiFeO3, synthesized by high-energy ball milling followed by annealing at low temperatures. Mixtures of Fe2O3 and Bi2O3, in a stoichiometric ratio, were mixed and milled for different durations from 0 to 13 h in an ambient air atmosphere and annealed for 2 h at different temperatures, from 350 to 750 degrees C in order to obtain BiFeO3. X-ray diffraction and Rietveld refinement were used to elucidate the phase transformation as a function of the synthesis parameters. The results showed that BiFeO3 particles with mostly a single phase (similar to 98 wt%) were fabricated by the assisted high-energy ball milling process, after 5 h of milling followed by heat treatment at 650 degrees C; higher milling durations and annealing temperatures promote perovskite decomposition. The obtained powder shows a weak ferromagnetic behavior, which changes to an antiferromagnetic order when the powder is pressed at 900 MPa and sintered at 800 degrees C for 2h. The magnetic and dielectric results confirm the multiferroic behavior of the obtained material. (C) 2017 Elsevier B.V. All rights reserved.