Structure, ferroelectric and magnetic characteristics of SmFeO3 and BaTiO3 co-modified BiFeO3 ceramics

Abstract

BiFeO3 is the most important single-phase room temperature multiferroic materials. In this work, the structure, ferroelectric and magnetic properties of ternary SmFeO3 and BaTiO3 co-substituted BiFeO3 ceramics prepared by standard solid-state reaction method were investigated. The phase composition and structural transformation were characterized by X-ray diffraction and Raman spectrum analysis. The substitution of BaTiO3 leads to the phase transformation from rhombohedral R3c to pseudocubic, and the pseudocubic phase is obtained at BF008-017 ceramic. Meanwhile, the orthorhombic Pbnm phase content gradually increases with the addition of SmFeO3. According to differential scanning calorimetry (DSC) analysis results, the magnetic transition temperature TN decreases linearly with increasing B-site substitution content. The P–E hysteresis loops measured with Positive-Up-Negative-Down (PUND) method showed the enhanced ferroelectricity at BF008-01, and the maximum piezoelectric coefficient d33 obtained was 17.3 pC/N. The magnetic properties were significantly enhanced, and the best magnetic properties were achieved at BF017-008 sample, where the maximum magnetization ~ Mmax = 0.99 emu/g and remnant magnetization ~ Mr = 0.44 emu/g. The origin of the enhanced magnetism of BiFeO3-based ceramics is complex, and the substitutions of A and B sites would affect magnetic properties.