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Antiferroelectric (Pb0.87Sr0.05Ba0.05La0.02)(Zr0.52Sn0.40Ti0.08)O3 thin film capacitors were fabricated for dielectric energy storage. Thin films with excellent crystal quality (FWHM 0.021°) were prepared on (100) SrRuO3/SrTiO3 substrates by pulsed laser deposition. The out-of-plane lattice constant of the thin film was 4.110 ± 0.001 Å. An average maximum recoverable energy storage density, 88 ± 17 J cm−3 with an efficiency of 85% ± 6% at 1 kHz and 80 ± 15 J cm−3 with an efficiency of 91% ± 4% at 10 kHz, was achieved at room temperature. The capacitor was fatigue resistant up to 106 cycles at an applied electric field of 2 MV cm−1. These properties are linked to a low level of hysteresis and slow polarization saturation. PbZrO3-derived oxide thin film capacitors are promising for high efficiency and low loss dielectric energy storage applications. [ABSTRACT FROM AUTHOR]

Precipitates have recently been found to significantly enhance the mechanical quality factor in piezoelectric ceramics. Such a piezoelectric hardening effect was attributed to strong interactions between ferroelectric domains and precipitates. In the present work, the response of domains to applied electric fields is observed in situ via transmission electron microscopy in aged (Ba, Ca)TiO3 ceramics with precipitates to reveal the underlying mechanism of this phenomenon. Ferroelectric domains in the Ba-rich matrix grain are observed to be more concentrated near non-polar Ca-rich precipitates. With increasing applied voltage, domains separate from precipitates merge together first, while those near precipitates persist to higher voltages. During ramping down, domains nucleate from precipitates. These direct observations confirm the strong interactions between ferroelectric domains and precipitates in piezoelectric ceramics. [ABSTRACT FROM AUTHOR]

The existence of a variety of phases and their transitions in the electric field-temperature (E-T) space of relaxor ferroelectrics make them an interesting research subject. To directly observe the evolution of domain morphology and crystal symmetry in ferroelectrics under either temperature change or an applied electric field, in-situ transmission electron microscopy (TEM) is often the preferred characterization technique. Accessing all the phases in the E-T space of a relaxor crystal requires in-situ TEM with capabilities of simultaneous heating and biasing. In this letter, such a dual-stimuli in-situ TEM technique is demonstrated on 0.75(Bi1/2Na1/2)TiO3–0.25SrTiO3, a relaxor ceramic with a thermal depolarization temperature Td of about 40 °C. Not only the domain structure change during thermal depolarization is directly seen, but also different microstructural responses under an applied electric field in the nonergodic and ergodic states are observed. The results prove that the dual-stimuli in-situ TEM technique is indispensable for exploring the rich physics in functional materials. [ABSTRACT FROM AUTHOR]