Magnetic properties of BiFeO3 obtained by mechanosynthesis

Abstract

Bismuth ferrites, BiFeO₃ (BFO) with perovskite structure and space group R3c nowadays are the only multiferroic ceramic known having simultaneous ferromagnetic and ferromagnetic order at temperature above ambient. This order is very fragile, and is affected by the processing method is therefore that the effect of time of high energy milling is shown in this work, from 0 to 420 min, on the crystal structure and magnetic properties BFO synthesized by this technique. Stoichiometric mixtures of metal oxides were subjected to high energy ball milling and subsequent heat treatment at 650 ° C for 2 h. X-ray diffraction and vibrating sample magnetometry were used to characterize the synthesized materials. BFO nanocrystalline particles successfully obtained with rhombohedral perovskite structure after 270 min milling time and heat treatment. BFO particles showed antiferromagnetic behavior at room temperature, with magnetization values similar to those reported by other methods. By increasing the milling time is easier to obtain pure phase BiFeO₃ assisted with heat treatment.