IMF2017

Over the past few years, the interest in intrinsic multiferroic materials has increased significantly due to the fact that these compounds present different ferroic orders in the same phase and a coupling between them. In particular, multiferroic materials with magnetoelectric multifunctional properties have experienced an exponential growth in research interest due to the fact that one single-phase presents (anti)ferromagnetic and (anti)ferroelectric orders and their coupling. Among them, BiFeO₃ is one of the most studied. It has a rhombohedral distorted perovskite structure and presents ferroelectric and antiferromagnetic ordering below 1098 K and 643 K, respectively. Even after many years of synthesis research, the preparation of highly resistive BiFeO₃ ceramics remains a challenge. The main problems are related to the presence of impurities. Ceramics prepared through the conventional solid-state reaction tend to have undesired phases and exhibit high leakage currents that prevent technological application and hinder the study of its properties. Many alternative routes of synthesis were proposed and/or tried along the years, unfortunately, the formation of Bi₂₅FeO₃₉ from the solid state reaction of Bi₂O₃ and Fe₂O₃ precedes the formation of the BiFeO₃. In this sense, we propose the use of high-energy ball milling to obtain highly homogeneous BiFeO₃ powders, allied to the fast firing method followed by quenching to room temperature to prevent the segregation and peritectic decomposition of secondary phases. As a result, highly resistive monolithic BiFeO₃ samples were achieved, and strong evidences of magnetoelectric coupling could be observed.