Large ferroelectric polarization of pure xBiFeO3-(1−x)BaTiO3 solid solution ceramics synthesized by microwave sintering

Abstract

BiFeO3-BaTiO3 (BFO-BTO)-based lead-free electroceramics have long been synthesized using the microwave sintering approach, but the resulting multiferroic performance has not been excellent. In this work, we report an attempt to achieve competitive ferroelectric properties in microwave-sintered xBFO-(1–x)BTO (x = 0.6–0.8) ceramics. Adopting a sintering process with a short dwell time of 30 min at 970 °C, we obtain high-quality ceramics with a high density, pure perovskite structure, uniform element distribution, and coarse grains. Furthermore, the fabricated ceramics can reproduce the typical characteristics of pure BFO-BTO, including a morphotropic phase boundary (MPB), relaxor ferroelectric behavior, weak ferromagnetism, and enhanced ferroelectricity near the MPB. More remarkably, a large intrinsic remnant polarization Pr as high as ∼28 μC/cm2 is achieved by combing the MPB-enhanced ferroelectricity and the advantages of microwave synthesis. The maximal Pr accomplished here is competitive with that of the same bulk solid solution obtained via other fabrication approaches. Our study illustrates that microwave synthesis is a powerful approach with which to prepare high-performance BFO-BTO-based ceramics.