Preparation, structures, and multiferroic properties of single phase Bi1-xLaxFeO3 (x=0-0.40) ceramics

A simple and effective method that solid state reaction followed by quenching process is developed to prepare multiferroic La-substituted BiFeO3 (Bi1-xLaxFeO3 (BLFOx) with x=0-0.40) ceramics. X-ray diffraction, x-ray photoelectron spectroscopy, and inductively coupled plasma studies show that the ceramics prepared under the optimized conditions are single phase. A phase transition from rhombohedral to orthorhombic phase is observed near x=0.30. This transition has great effects on the multiferroic properties. Magnetic and electric measurements reveal that the BLFO0.30 has enhanced multiferroic properties with two times remnant magnetization and polarization of 0.041 emu/g and 22.4 mu C/cm(2), respectively. The enhanced multiferroic properties are attributed to the enhanced magnetoelectric interaction, which results from the La substitution-induced destruction of the spin cycloid. These results show that BiFeO3-based perovskite solid solution with no other ferroelectric end member can have improved multiferroic properties via enhancing magnetoelectric interaction. This work may provide some guidelines for further study on BiFeO3 and BiFeO3-based solid solutions. (c) 2006 American Institute of Physics.