Ion-Pair Engineering-Induced High Piezoelectricity in Bi 4 Ti 3 O 12 -Based High-Temperature Piezoceramics.

High-temperature piezoceramics are highly desirable for numerous technological applications ranging from the aerospace industry to the nuclear power sector. However, it is a grand challenge to achieve excellent piezoelectricity and high Curie temperature ( T c ) simultaneously because there is a contradiction between the large piezoelectric coefficient and high Curie temperature in piezoceramics. Here, we provide a perspective via B-site ion-pair engineering to design piezoceramics with high performance for high-temperature applications. In bismuth-layered Bi 4 Ti 2.93 (Zn 1/3 Nb 2/3 ) 0.07 O 12 ceramics, high piezoelectricity of d 33 = 30.5 pC/N (more than four times higher than that of pure Bi 4 Ti 3 O 12 ( d 33 = 7.3 pC/N) ceramics) in conjunction with excellent thermal stability, high Curie temperature T c = 657 °C, and large dc resistivity of ρ = 1.24 × 10 7 Ω·cm at 500 °C (three orders of magnitude larger than that of the pure Bi 4 Ti 3 O 12 ceramics) are achieved by B-site Nb 5+ -Zn 2+ -Nb 5+ ion-pair engineering. Excellent piezoelectricity is ascribed to sufficient orientation of the fine lamellar ferroelectric domain with the introduction of Nb 5+ -Zn 2+ -Nb 5+ ion-pairs. The good temperature stability of d 33 originates from the stability of the crystal structure and the robustness of the oriented ferroelectric domain. The significantly improved resistivity is due to the restricted mobility of oxygen vacancies. This work presents a brand-new technique for achieving high-temperature piezoceramics with high performance by B-site ion-pair engineering.