High-Performance Textured Bismuth Layer Structured Piezoceramics with Template-Induced Orientation

Bismuth layer-structured piezoelectric ceramics, Na_0.5Bi_4.5Ti₄O₁₅ (NBT), hold significant promise for high-temperature piezoelectric applications due to their high Curie temperatures (T_C). However, its widespread application is limited by the intrinsically poor piezoelectric performance, which stems from the crystal structure that constrains the spontaneous polarization. Here, a strategy of mixing plate-like templates with solid-state-derived matrix powder, which allows the templates to induce grain alignment during conventional sintering, was successfully employed to fabricate (00l)-textured NBT ceramics with a Lotgering factor of 80.6%. The textured ceramic exhibits an ultrahigh piezoelectric coefficient (d₃₃) of 41.1 pC/N among NBT-based piezoelectric ceramics, while maintaining a low dielectric loss (tan δ = 0.48%) and a high T_C of 660 °C. Multitechnique analyses reveal that this synergistic property optimization originates from the template-induced grain alignment, which facilitates domain switching. The texturing method employed here enhances the piezoelectric properties without substantially degrading the electrical resistivity. This work presents a simple fabrication route for textured ceramics, offering insights for the design of high-performance textured bismuth layer-structured piezoelectric materials.