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High polarization of ferroelectric materials has profound research significance and is the decisive factor in the application of energy storage, pyroelectricity, and explosive energy conversion. Herein, in force-electric conversion field, an ultrahigh remanent polarization (51.43 μC/cm2) and record-breaking energy density (4.59 J/cm3) after poling were achieved with a lead-free (1 − x)Bi0.5Na0.5TiO3 − xAgNbO3 [(1 − x)BNT – xAN] relaxor ceramics. The enhancement effect of AgNbO3 on polarization is attributed to the increase in lattice distortion and orientation after poling. Additionally, a significant force-electric conversion effect under hydrostatic pressure (depolarization rate ∼44.8%, 400 MPa) and shock pressure (depolarization rate ∼54.4%, 6.3 GPa) in (1 − x)BNT – xAN was attributed to the pressure-driven ferroelectric/relaxor (FE/RE) phase transition. This work is expected to enlighten the further design of ferroelectric materials with high polarization for pulse power energy conversion application. [ABSTRACT FROM AUTHOR]

Recently, dielectrics for energy storage have been attracting increasing attention due to their ultrahigh power density. However, the widespread application of dielectrics remains limited by their low energy density. In this work, lead-free single-phase relaxor (1 − x)Ba0.55Sr0.45TiO3-xBiMg2/3Nb1/3O3 [(1 − x)BST-xBMN] (x = 0, 0.05, 0.07, and 0.10) bulk ceramics were prepared by a conventional solid-state reaction process. The dielectric properties, the relaxor behavior, and the energy storage properties were explored in detail. With increasing BMN content, the observed increase in activation energy (Ea) and the decrease in freezing temperature (Tf) indicate that the coupling between polar nano-regions (PNRs) gradually weakened, leading to the decrease in remanent polarization (Pr) and the increase in energy storage efficiency (η). For the composition x = 0.07, the breakdown strength (BDS) significantly increased from 240 kV cm of pure BST to 450 kV cm. Finally, large Wrec (4.55 J cm3) and high η (81.8%) were achieved in 0.93BST-0.07BMN ceramics. The results demonstrate that the (1 − x)BST-xBMN ceramics have superior potential for use in advanced pulsed power capacitors. [ABSTRACT FROM AUTHOR]

Polarization switching and energy storage properties of highly (100) oriented antiferroelectric (AFE) (Pb,La)(Zr,Ti)O3 thin films (≤250 nm) deposited via a sol-gel process with both LaNiO3 and Pt top electrodes were investigated. By using LaNiO3 top electrodes, the energy density as well as energy efficiency can be enhanced by 4.6 J/cm3 and 11%, respectively. Furthermore, the films with LaNiO3 top electrodes are more capable of providing high energy density over a wide temperature regime above room temperature compared to Pt. This work clearly highlights that oxide top electrodes can greatly improve the energy storage performance of antiferroelectric thin film capacitors. [ABSTRACT FROM AUTHOR]

The effect of residual stress on energy storage property was investigated for a series of PbZrO3 thin films on SrTiO3 and Si substrates. Compressive or tensile residual stress influences the critical electric field EA for the ferroelectric-to-antiferroelectric phase transition, thus for films with (110)/(101) orientation, energy density W of films on SrTiO3 is 38% larger than films on Si; in contrast, (001)-oriented PbZrO3 films on SrTiO3 show slightly smaller W compared to films on Si. We conclude that the different responses of W to stress are related to the different constrain states in films with different orientations. [ABSTRACT FROM AUTHOR]