Improved ferroelectric, piezoelectric, and magnetic properties in BiFeO3–(Ba0.85Ca0.15)TiO3 ceramics through Mn addition.

Integrating multiple functions in a single compound is still attractive and necessary to meet the demand of device miniaturization. In this work, we systemically modulate multifunctional properties in the 0.74BiFeO₃–0.26(Ba_0:85Ca_0:15)TiO₃–x wt. % MnO₂ solid solution with the addition of MnO₂. A highly rectangular and saturated polarization–hysteresis (P–E) loop is obtained with a large remanent polarization P_r of 49.5 μC/cm² as x = 0:8. Furthermore, the piezoelectric coefficient d₃₃ also obviously improved with an optimized d₃₃ = 137 pC/N by the introduction of MnO₂ due to the grain size effect, the improvement of insulation, and relaxation regulation. With the addition of MnO₂, the remanent magnetization M_r increases monotonically because of the enhanced exchange interactions between Fe²⁺and Fe³⁺. The results may provide an effective way to explore promising multifunctional materials in BiFeO₃-based ceramics. [ABSTRACT FROM AUTHOR]