Grain-Oriented Ferroelectric Ceramics with Single-Crystal-like Piezoelectric Properties and Low Texture Temperature.
Yunfei ChangJie WuZhen LiuEnwei SunLinjing LiuQiangwei KouFei LiBin YangWenwu CaoPublished in: ACS applied materials & interfaces (2020)
High-performance piezoelectrics are pivotal to various electronic applications including multilayer actuators, sensors, and energy harvesters. Despite the presence of high Lotgering factor F001, two key limitations to today's relaxor-PbTiO3 textured ceramics are low piezoelectric properties relative to single crystals and high texture temperature. In this work, Pb(Yb1/2Nb1/2)O3-Pb(Mg1/3Nb2/3)O3-PbTiO3 (PYN-PMN-PT) textured ceramics with F001 ∼ 99% were synthesized at only 975 °C through liquid-phase-assisted templated grain growth, where of particular significance is that single-crystal properties, i.e., very large electrostrain Smax/Emax ∼ 1830 pm V-1, giant piezoelectric figure of merit d33 × g33 ∼ 61.3 × 10-12 m2 N-1, high electromechanical coupling k33 ∼ 0.90, and Curie temperature Tc ∼ 205 °C, were simultaneously achieved. Especially, the Smax/Emax and d33 × g33 values correspond to ∼180% enhancement as compared to the regularly 1200 °C-textured ceramics with F001 ∼ 96%, representing the highest values ever reported on piezoceramics. Phase-field simulation revealed that grain misorientation has a stronger influence on piezoelectricity than texture fraction. The ultrahigh piezoelectric response achieved here is mainly attributed to effective control of grain orientation features and domain miniaturization. This work provides important guidelines for developing novel ceramics with significantly enhanced functional properties and low synthesis temperature in the future and can also greatly expand application fields of piezoceramics to high-performance, miniaturized electronic devices with multilayer structures.