Lead-Free Textured Ceramics with Ultrahigh Piezoelectric Properties by Synergistic Design.

Lead-free ceramics with superior piezoelectric performance are highly desirable in various electromechanical applications. Unfortunately, it is still challenging to achieve significantly enhanced piezoelectricity without sacrificing the Curie temperature ( T c ) in current BaTiO 3 -based ceramics. To address this issue, a synergistic design strategy of integrating crystallographic texture, multiphase coexistence, and doping engineering is proposed here. Highly [001] c -textured (Ba 0.95 Ca 0.05 )(Ti 0.92 Zr 0.06 Sn 0.02 )O 3 ceramics are synthesized through Li-related liquid-phase-assisted templated grain growth, with improved grain orientation quality ( f of ∼96% and r of ∼0.16) achieved at substantially reduced texture temperatures. Encouragingly, ultrahigh comprehensive piezoelectric properties, i.e., piezoelectric coefficient d 33 of ∼820 pC N -1 , electrostrain S max / E max of ∼2040 pm V -1 , and figure of merit d 33 × g 33 of ∼23.5 × 10 -12 m 2 N -1 , are simultaneously obtained without sacrificing T c , which are also about 2.3, 2.4, and 4.3 times as high as those of non-textured counterpart, respectively. On the basis of the experiments and theoretical modeling, the outstanding piezoelectric performance is attributed to more effective exploration of property anisotropy and easier polarization rotation/extension, owing to improved grain orientation quality, dissolution of templates into oriented grains, coexisting R + O + T phases, and domain miniaturization. This work provides important guidelines for developing novel ceramics with outstanding piezoelectric properties and can largely expand application fields of textured BaTiO 3 -based ceramics into high-performance and multilayer electronic devices.