Enhanced piezoelectric properties and depolarization temperature in textured (Bi0.5Na0.5)TiO3-based ceramics via homoepitaxial templated grain growth

Abstract

Enhanced piezoelectric response was usually achieved in (Bi0.5Na0.5)TiO3 (BNT)-based ceramics with sacrifice of depolarization temperature Td, seriously limiting their usage range in electromechanical applications. In this work, we propose to explore piezoelectric anisotropy and domain engineering in composition & microstructure-controlled textured ceramics to resolve this issue. [001]c-textured 0.94(Bi0.5Na0.5)TiO3–0.06BaTiO3 (0.94BNT-0.06BT) ceramics with Lotgering factor F001∼91% were fabricated through homoepitaxial templated grain growth (TGG) via using 0.94BNT-0.06BT microplatelet templates. The textured samples exhibited more ordered domains with facilitated domain switching behavior, being consistent with saturated high polarization achieved at lower electric fields. Increasing F001 to above 60% enables rapid enhancement of piezoelectric response. Notably, compared to non-textured counterpart, the maximally textured ceramics exhibited ∼236% enhanced piezoelectric coefficient (d33∼302 pC/N) and ∼280% enhanced piezoelectric voltage coefficient (g33∼49.8 × 10−3 Vm/N), together with slightly increased depolarization temperature (Td∼106 °C). Moreover, those values are approaching or even higher than the single-crystal values. This work not only provides important guidelines for design and synthesis of novel textured ceramics with improved comprehensive electrical properties, but also can expand application fields of BNT-based ceramics.