A rapid surge in the research on piezoelectric sensors is occurring with the arrival of the Internet of Things. Single-phase oxide piezoelectric materials with giant piezoelectric voltage coefficient (g, induced voltage under applied stress) and high Curie temperature (T_c) are crucial towards providing desired performance for sensing, especially under harsh environmental conditions. Here, we report a grain-oriented (with 95% texture) modified PbTiO₃ ceramic that has a high T_c (364 °C) and an extremely large g₃₃ (115 × 10⁻³ Vm N⁻¹) in comparison with other known single-phase oxide materials. Our results reveal that self-polarization due to grain orientation along the spontaneous polarization direction plays an important role in achieving large piezoelectric response in a domain motion-confined material. The phase field simulations confirm that the large piezoelectric voltage coefficient g₃₃ originates from maximized piezoelectric strain coefficient d₃₃ and minimized dielectric permittivity ɛ₃₃ in [001]-textured PbTiO₃ ceramics where domain wall motions are absent.

Electromechanical coupling factor, k, of piezoelectric materials determines the conversion efficiency of mechanical to electrical energy or electrical to mechanical energy. Here, we provide an fundamental approach to design piezoelectric materials that provide near-ideal magnitude of k, via exploiting the electrocrystalline anisotropy through fabrication of grain-oriented or textured ceramics. Coupled phase field simulation and experimental investigation on textured Pb(Mg_1/3Nb_2/3)O₃-Pb(Zr,Ti)O₃ ceramics illustrate that k can reach same magnitude as that for a single crystal, far beyond the average value of traditional ceramics. To provide atomistic-scale understanding of our approach, we employ a theoretical model to determine the physical origin of k in perovskite ferroelectrics and find that strong covalent bonding between B-site cation and oxygen via d-p hybridization contributes most towards the magnitude of k. This demonstration of near-ideal k value in textured ceramics will have tremendous impact on design of ultra-wide bandwidth, high efficiency, high power density, and high stability piezoelectric devices.

Dielectric capacitors with high energy storage performance are highly desired for next-generation advanced high/pulsed power capacitors that demand miniaturization and integration. However, the poor energy-storage density that results from the low breakdown strength, has been the major challenge for practical applications of dielectric capacitors. Herein, we propose a heterovalent-doping-enabled atom-displacement fluctuation strategy for the design of low-atom-displacements regions in the antiferroelectric matrix to achieve the increase in breakdown strength and enhancement of the energy-storage density for AgNbO₃-based multilayer capacitors. An ultrahigh breakdown strength ~1450 kV·cm⁻¹ is realized in the Sm_0.05Ag_0.85Nb_0.7Ta_0.3O₃ multilayer capacitors, especially with an ultrahigh U_rec ~14 J·cm⁻³, excellent η ~ 85% and P_D,max ~ 102.84 MW·cm⁻³, manifesting a breakthrough in the comprehensive energy storage performance for lead-free antiferroelectric capacitors. This work offers a good paradigm for improving the energy storage properties of antiferroelectric multilayer capacitors to meet the demanding requirements of advanced energy storage applications.

Piezoelectric materials enable the conversion of mechanical energy into electrical energy and vice‐versa. Ultrahigh piezoelectricity has been only observed in single crystals. Realization of piezoelectric ceramics with longitudinal piezoelectric constant (d₃₃) close to 2000 pC N^–1, which combines single crystal‐like high properties and ceramic‐like cost effectiveness, large‐scale manufacturing, and machinability will be a milestone in advancement of piezoelectric ceramic materials. Here, guided by phenomenological models and phase‐field simulations that provide conditions for flattening the energy landscape of polarization, a synergistic design strategy is demonstrated that exploits compositionally driven local structural heterogeneity and microstructural grain orientation/texturing to provide record piezoelectricity in ceramics. This strategy is demonstrated on [001]_PC‐textured and Eu³⁺‐doped Pb(Mg_1/3Nb_2/3)O₃‐PbTiO₃ (PMN‐PT) ceramics that exhibit the highest piezoelectric coefficient (small‐signal d₃₃ of up to 1950 pC N^–1 and large‐signal d₃₃* of ≈2100 pm V^–1) among all the reported piezoelectric ceramics. Extensive characterization conducted using high‐resolution microscopy and diffraction techniques in conjunction with the computational models reveals the underlying mechanisms governing the piezoelectric performance. Further, the impact of losses on the electromechanical coupling is identified, which plays major role in suppressing the percentage of piezoelectricity enhancement, and the fundamental understanding of loss in this study sheds light on further enhancement of piezoelectricity. These results on cost‐effective and record performance piezoelectric ceramics will launch a new generation of piezoelectric applications.

With strain engineer and MnO₂ addition, an ultra-high energy-storage density W_rec = 7.9 J cm⁻³ and efficiency η = 71% were achieved in Ag(Nb_0.85Ta_0.15)O₃ + 0.25 wt% MnO₂ multilayer capacitors.

Energy-storage performances of NaNbO₃ system were effectively enhanced by composition engineering inducing relaxor behavior and grain refinement. Excellent W_rec = 3.7 J cm⁻³ and η = 82.1% were achieved in the NN-0.04CZ-0.16BNT multilayer capacitors.