High Piezoelectricity and Temperature Stability via Stabilized Polar Distortion

ABSTRACT Simultaneously combining high piezoelectric performance with excellent thermal stability is essential for piezoelectrics operating under high‐temperature conditions, yet these two attributes are often in competition. Here, we propose a design strategy that stabilizes the intrinsic lattice contribution by constructing a mixed‐symmetry ferroelectrically distorted state and demonstrate its effectiveness in Pb(Zr 0.53 Ti 0.47 )O 3 ‐ x Nb (N x ) ceramics. The optimized N3 composition exhibits a high piezoelectric coefficient d 33 of 550 pC/N and a high Curie temperature T C of 367°C. Over the wide temperature range of 25–300°C, the variations in piezoelectric coefficient ( d 33 ) and electromechanical coupling factor ( k p ) are limited to only 6% and 9%, respectively. In situ temperature‐dependent structural analyses reveal that the enhanced piezoelectricity and thermal robustness originate from a ferroelectric distortion that is strongly developed at room temperature due to niobium doping and remains stable up to 300°C, as further corroborated by first‐principles calculations and scanning probe microscopy measurements. This mixed‐symmetry‐stabilization strategy provides a generalizable route to overcoming the conventional trade‐off between performance and stability and offers design guidelines for next‐generation high‐performance piezoceramics tailored for high‐temperature applications.