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Antiferroelectrics (AFEs) are widely used for energy storage capacitors. At present, there are two methods to evaluate the energy density of AFE: the recoverable energy density Wre calculated by the low‐frequency P–E loop and the dynamic discharge energy density Wdis calculated by the fast discharge current. It has been widely observed that the value of Wdis is lower than Wre but less attention was paid to how to increase Wdis. Compared with Wre, the value of Wdis is closer to the energy density of AFE pulse capacitors in practical applications. In this work, the effects of phase transition properties on the dynamic discharge energy density were studied from the aspect of domain switching mobility. Compositions with P–E loop varying from "square" to "slant" were fabricated. It was found that in AFEs with "square" P–E loops, the recoverable energy density Wre was remarkably higher than Wdis. By modifying the P–E loops to long slim, the value of Wdis tended to be close to Wre, resulting in higher dynamic discharge energy efficiency. This indicates that by adjusting the P–E loop, higher Wdis can be achieved in AFE with lower Wre. The AFEs with long slim P–E loops also have faster discharge speeds, leading to higher power density. The outstanding fast discharge performance of AFEs with long slim P–E loops originated from their faster domain mobility and less viscous force during domain switching. This work provides a new approach to designing the AFEs energy storage materials by tuning their dynamic phase‐transition properties and domain mobility. [ABSTRACT FROM AUTHOR]

In practical applications, high power is the ultimate goal of dielectric capacitors, while most research has focused on enhancing energy density. Far less attention is paid to enhancing discharge speed and achieving high power. In the present work, we studied the fast discharge behavior of (Pb0.98−xLa0.02Srx)[(Zr0.50Sn0.50)0.88Ti0.12]0.995O3 antiferroelectric ceramics and investigated the effects of phase transition on energy release rates. By doping Sr content, the antiferroelectricity was enhanced and the sharpness of the hysteresis loop was reduced, suppressing the constant and slow discharge current plateau caused by ferroelectric–antiferroelectric (FE–AFE) switching. As a result, the average power density was enhanced from 0.3 to 4.1 MW/cm3. More importantly, higher power density could be achieved in composition with lower discharge energy density but faster discharge speed. This study proves the significance of discharge speed and provides a new approach to develop dielectric materials for high-power applications. [ABSTRACT FROM AUTHOR]

Antiferroelectric (AFE) ceramic materials possess ultrahigh energy storage density due to their unique double hysteresis characteristics, and PbZrO 3 is one of the promising systems, but previous materials still suffer from the problem that energy storage density and energy storage efficiency can hardly be improved synergistically. In this work, a multiple optimization strategy is proposed to substantially improve the energy storage efficiency while maintaining the high energy storage density of PZ-based AFE ceramics. Sr2+-doped (Pb 0.90 La 0.02 Sr 0.08)[(Zr 0.5 Sn 0.5) 0.9 Ti 0.1 ] 0.995 O 3 ceramics was successfully synthesized by viscous polymer process and two-step sintering. The diffuse phase transition constructed in this ceramic depleted the threshold electric field hysteresis and current while the breakdown field strength was increased again. An ultrahigh recoverable energy density (W rec) of 7.9 J/cm3 with a high energy storage efficiency (η) of 96.4 % are achieved synchronously at an electric field of 510 kV/cm. Moreover, the AFE ceramics possess remarkable discharge energy storage properties with a high discharge energy density (W d) of 7.4 J/cm3 and a large power density (P d) of 224 MW/cm3. [ABSTRACT FROM AUTHOR]

PbHfO3 was found with antiferroelectricity early and identical to PbZrO3 in many aspects but much less attention was received. In the present work, the PbHfO3‐based ceramics with compositions of Pb0.97La0.02(Hf1−xTix)O3 (PLHT, 0 ≤ x ≤ 0.1) were fabricated, and their antiferroelectricity was investigated. All the compositions have an initially antiferroelectric (AFE) phase and by introducing Ti content, the AFE phase is destabilized. Typical AFE‐like double polarization‐electric field (P–E) loop was observed in compositions with 0 ≤ x ≤ 0.08. When x = 0.10, the composition is initially AFE but remains ferroelectric (FE) phase after the removal of the external electric field, resulting in an FE‐like single P–E loop. The temperature dependence of phase transition and multiple phase transition behavior in PLHT was also studied. This work revealed the antiferroelectricity in PLHT with low Ti content. In addition, the potential application of PLHT for energy storage and conversion was also discussed. A recoverable energy density of 7.1 J/cm3 and efficiency of 78.5% were achieved in Pb0.97La0.02HfO3 at 300 kV/cm. [ABSTRACT FROM AUTHOR]

The energy density of dielectrics could be evaluated both via low-frequency P–E loop (quasi-static recoverable energy density, Wre) and fast discharge current (dynamic discharge energy density, Wdis). The value of Wdis represents the useful energy, which can be converted to electrical energy while most work about high-energy-density dielectrics is focused on enhancing Wre. In this work, we investigated the relationship between Wdis and Wre in (Pb1 − 3x/2Lax)[(Zr0.45Sn0.55)0.99Ti0.01]O3 antiferroelectrics. Tuning the phase transition properties could improve the fast discharge capability by reducing the difference between Wdis and Wre and accelerating the energy release rate. At 300 kV/cm, the composition with x = 0 has the highest Wre of 6.7 J/cm3 but a lower Wdis of only 4 J/cm3 and longer discharge time duration, indicating a "high-energy-density" (highest Wre) quasi-static performance but "low-energy-density" (lower Wdis) and slow discharge performance during fast discharge. A highest Wdis of 5.9 J/cm3 and power density were achieved in composition with x = 0.2 though with lower Wre. The various fast energy release performance was explained by their different domain mobility and phase switching behavior. Thus, purely pursing high Wre is with limitation and suppressing the difference between Wdis and Wre is with great significance. This work will give an approach for the development of energy storage dielectrics by connecting their fast discharge performance with polarization mechanism. [ABSTRACT FROM AUTHOR]

Antiferroelectrics (AFEs) with high energy density and fast discharge speed are greatly needed to improve the performance of capacitors. In the present work, La-doped PbHfO3 ceramics were fabricated and the antiferroelectricity was investigated. The complicated phase transition behavior at both high electric field and rising temperature in composition Pb0.94La0.04HfO3 was revealed. Multiple phase transition was observed at high field, and when rising the temperature to 110 °C, an intermediate phase transition to another AFE phase was observed. The Pb0.94La0.04HfO3 ceramics have a high recoverable energy density of 10.2 J/cm3 and efficiency of 81.7%. Double P–E loop could be observed even at 180 °C, ensuring the high energy density at high temperature. In addition, a high current density of 2109 A/cm2 and a power density of 369 MW/cm3 could be obtained. This work revealed the antiferroelectricity in La-doped PbHfO3 ceramics and proved their potential for high energy and power density applications. [ABSTRACT FROM AUTHOR]

Capacitors are widely used as energy storage elements in electric vehicles (EVs) and pulsed power. At present, it is still challenging to develop capacitor dielectrics with good energy storage and discharge performance. In this work, antiferroelectric (AFE) ceramics (Pb0.94La0.04)[(Zr0.6Sn0.4)0.92Ti0.08]O3 with enhanced antiferroelectricity were fabricated by a rolling process. The obtained ceramics have a high recoverable energy density of 5.2 J/cm3 and an extremely high efficiency of 91.2% at 327 kV/cm. The ceramics have good energy storage and discharge performance in the temperature range from −40°C to 100°C due to the existence of AFE phase. An energy density of 3.7 J/cm3 can be released at 200 kV/cm in less than 500 ns and the discharge current keeps stable after 1000 charge‐discharge cycles. By direct short experiment, a current density of 1657 A/cm2, which is the highest result in recently developed AFE ceramics, and a power density of 228 MW/cm3 were achieved. The possibility of using AFEs at low temperature was confirmed. The excellent energy storage and discharge performance prove the great potential of the obtained ceramics in high energy and power density applications. [ABSTRACT FROM AUTHOR]

Abstract Antiferroelectric ceramics are superior energy storage materials with high energy storage densities, small size, low price, etc. In this paper, with (Pb 0.96 La 0.04)(Zr 0.9 Ti 0.1) 0.99 O 3 (PLZT4/90/10) as a representative, the effect of silver oxide doping on the dielectric properties of ceramics was investigated. PLZT4/90/10 ceramics prepared by the solid phase method was doped with 0 wt%, 0.1 wt%, 0.5 wt%, 1.0 wt% and 1.5 wt% of Ag 2 O, and the effect of the addition of Ag 2 O was analyzed on dielectric, energy storage and conductive properties. Ag+ replaces the A-position of Pb2+ in the lattice, which leads to generate more oxygen vacancy in the lattice. Incorporation of silver oxide improves the releasable energy storage density (W re) and the energy release efficiency (η). When the content of Ag 2 O is 1.0%, the releasable energy density reaches the maximum value of 2.22 J/cm3 and the energy release efficiency is raised to 78.69%. The releasable energy density and the energy release efficiency are listed at different temperatures for different doping amounts. It can be seen that Ag 2 O doping can also promote the temperature stability of the energy storage density. In addition, the doping of Ag 2 O has a good effect on smoothing the temperature dependence curves of dielectric constant and improving the resistivity of ceramics of PLZT4/90/10 ceramics. As the dielectric constant, energy storage density and other aspects are concerned, Ag 2 O doping has a beneficial effect on the performance of capacitor applications for PLZT4/90/10 ceramics. [ABSTRACT FROM AUTHOR]

• In this work, Pb 1−x Lax[(Zr 0.55 Sn 0.45) 0.92 Ti 0.08 ] 1−x∕4 O 3 (x = 0%, 2%, 4%, 6%) antiferroelectric ceramics are fabricated by a rolling process. • Effects of La addition on the average grain size, the field-induced strain and the energy efficiency were investigated comparatively. • Meanwhile, the released energy density calculated by "quasi-static" method (W re) and "dynamic" (W dis) method were researched. • Specifically, the composition with 4%La doped has the best comprehensive performance, with a highest recoverable energy density of 5.61 J/cm3 and ultrahigh efficiency of 90% at 410 kV/cm. • Moreover, a discharge energy density of 3.6 J/cm3 can be obtained at 222 kV/cm and 90% can be released within 0.68 μs. • By direct short experiment, a current density of 1599A/cm2 was obtained. These results indicted PLZST 4/55/45/8 is promising to be used for high energy density capacitors. In order to improve the energy storage and discharge performance of ceramic dielectric capacitors, antiferroelectric materials have drawn wide attention. In this work, a comprehensive investigation on P b 1 − x L a x [ (Z r 0.55 S n 0.45 ) 0.92 T i 0.08 ] 1 − x ∕ 4 O 3 (x = 0%, 2%, 4%, 6%) antiferroelectric ceramics are fabricated by a rolling process. With the addition of lanthanum(La), the average grain size and the electric-field-induced strain are suppressed. However, the energy conversion efficiency, particularly the efficiency of −60 °C, is enhanced with increasing La content. In addition, the released energy density calculated by the "quasi-static" method(W re) and "dynamic" method(W dis) were investigated comparatively. As the content of La increase, the discrepancy between W re and W dis gradually decreased. Specifically, the composition with 4%La doped has the best comprehensive performance, with the highest recoverable energy density of 5.61 J/cm3 and ultrahigh efficiency of 90% at 410 kV/cm. Moreover, a discharge energy density of 3.6 J/cm3 can be obtained at 222 kV/cm and 90% can be released in 0.68 μ s. By directly short experiment, a current density of 1599A/cm2 and power density of 177 MW∕cm3 were obtained. These results indicated that PLZST 4/55/45/8 is promising for high electric energy and power density capacitors. [ABSTRACT FROM AUTHOR]

PLZST-based antiferroelectric (AFE) ceramics with high recoverable energy density (W re) and efficiency (η) can be applied to pulsed power electronic devices. However, this application is constrained by the high sintering temperature (ST, 1250–1320 °C) of the ceramics per se. In this context, this study introduced a new glass phase of Ba 2 CO 3 –Al 2 O 3 –SiO 2 –K 2 CO 3 (BASK) into Pb 0.95 La 0.02 Sr 0.02 (Zr 0.50 Sn 0.40 Ti 0.10)O 3 (PLSZST) AFE ceramics by using a traditional solid-state method. By doping 0.5 wt% BASK, the ST of PLSZST ceramics was significantly reduced from 1300 °C to 1020 °C and a high W re of 3.54 J/cm3 and a high η of 86% were yield, when the electric breakdown strength increased to 230 kV/cm. In addition, a pulse discharge energy density of 2.47 J/cm3, and an extremely fast discharge speed (<0.5 μs), as well as acceptable thermal stabilities of both W re and η within 30–110 °C temperature range, were achieved. Conclusively, this AFE ceramic composition with glass additives has a great potential to be used in base metal inner-electrode multilayer ceramic capacitors for pulse power applications. [ABSTRACT FROM AUTHOR]