Structure, ferroelectric and piezoelectric properties of multiferroic Bi0.875Sm0.125FeO3 ceramics

Abstract: With a rhombohedra-like structure, the Bi0.875Sm0.125FeO3 ceramics show much-improved ferroelectric and piezoelectric properties: a saturated ferroelectric polarization of 40μC/cm2 and a piezoelectric d 33 of 45pC/N at 20°C. After the polarized sample was annealed at 600°C, its d 33 decreases to ∼20pC/N. Besides, Bi0.875Sm0.125FeO3 shows dielectric or impedance resonances at 20–550°C, suggesting that the ferroelectric component with high Curie temperature still partially remained at 550°C. However, the impedance and the resistance decrease so fast with temperature increasing that both of them are below 1000ohm above 420°C. Even so, this piezoelectric resonance method can explore leaky ferroelectrics at high temperature. [Copyright &y& Elsevier]