Improved ferroelectricity and ferromagnetism of Eu-modified BiFeO3–BaTiO3 lead-free multiferroic ceramics

Multiferroic ceramics of 0.75Bi1−x Eu x FeO3–0.25BaTiO3 + 1 mol% MnO2 were synthesized by a conventional solid state reaction method and the effects of Eu doping on microstructure, ferroelectric, ferromagnetic and piezoelectric properties of the ceramics were investigated. All the ceramics exhibit a pure perovskite structure without any secondary phases. After the addition of Eu3+ ions, the crystal structure of the ceramics is transformed from rhombohedral to tetragonal phase at x = 0.025. The ferroelectricity and ferromagnetism of the ceramics are improved. For the ceramic with x = 0.025, the optimum remanent polarization of 18.3 μC/cm2 and good piezoelectricity of 82 pC/N are obtained. The saturated magnetization M s and remanent magnetism M r of the ceramics are improved by 165 and 141 % with x increasing from 0 to 0.175, respectively.