Textured Sr₂Nb₂O₇ ceramics: Microstructure design, high temperature ferroelectric and piezoelectric performance.

Sr2Nb2O7 (SNO) ceramics are promising high‐temperature piezoelectric materials due to their high Curie temperature (TC), good thermal stability, and high electrical resistivity. However, SNO presents low piezoelectric activity (d33 < 1 pC/N). Here, we successfully obtain textured SNO ceramics with an orientation factor of 0.86 by microstructure regulation. Saturated polarization‐electric loop was obtained in textured ceramic with remanent polarization Pr∼3.56 µC/cm2 and coercive field EC∼53.4 kV/cm. The piezoelectric coefficient d33 of the textured SNO ceramics is increased to 3.2 pC/N, with a high TC of 1342°C, while the low‐textured SNO ceramics exhibit no effective d33. Meanwhile, the piezoelectric coefficient d33 of textured SNO ceramics maintains consistency even at 1300°C, showing excellent thermal stability. The underlying mechanism driving this improvement is elucidated, emphasizing the facilitated domain‐wall motion enabled by the engineered microstructure. Furthermore, textured SNO ceramics exhibit high resistivity of 1.33 × 106 Ω⋅cm at 800°C. This study presents a simple and feasible microstructure engineering approach to enhance the piezoelectric properties of layer‐structured materials, offering valuable insights into the design and development of ceramics for diverse applications. Textured SNO ceramics achieved through microstructure regulation exhibit an orientation factor of 0.86, improved piezoelectric properties, and exceptional thermal stability with a high Curie temperature of 1342°C. These ceramics maintain high resistivity at elevated temperatures, demonstrating enhanced domain‐wall motion and a significant increase in the piezoelectric coefficient to 3.2 pC/N, even at 1300°C. [ABSTRACT FROM AUTHOR]