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Ceramic-based capacitors with excellent recoverable energy storage density (Wrec) and efficiency (η) are greatly desired for pulsed capacitors but challenge as well. In this work, the high energy storage performance with an Wrec of 5.1 J/cm3, an η of 93.4%, and an ultrafast discharge–charge speed t0.9 of 72 ns is achieved in unusual interstitial and substitutional hybrid solid solution of Sr0.64Bi0.18Na0.18TiO3-ZnO (SBNT-Zn), in which two Zn2+ ions occupy one A-site, while one Zn2+ ion occupies one B-site of ABO3 perovskite lattice simultaneously. The addition of Zn2+ increases lattice distortion and breaks long-range ferroelectric order, resulting in more highly dynamic polar nanoregions, higher relaxation behaviors as well as larger polarization (ΔP). Moreover, the extraordinary hybrid solid solution configuration enhances the bandgap of SBNT-Zn and ZnO as a sintering aid refines grain size, both help to enhance electric breakdown strength. This work affirms the feasibility and reliability of forming a hybrid solid solution to develop high-performance ferroelectric materials. [ABSTRACT FROM AUTHOR]

Progress in micro/nano-electro-mechanical system (M/NEMS) and microelectronics technologies urgently require the synchronous development of the micro/nano energy storage systems. Herein, a novel patterned Si/TiN/Ge electrode is fabricated on the Si substrate surface by the facile femtosecond-laser direct writing and the microelectronic thin film deposition techniques. The surface-engraved Si/TiN/Ge electrode displays superior cyclability and rate capability when evaluated as anode for lithium ion microbatteries (LIMBs). The patterned TiN interlayer can act as an effective buffer layer to optimize the Li ions storage in the Si substrate, and the introduction of the Ge nanocomposites would further enhance the areal capacity, thus eventually bring the improved electrochemical performance. Moreover, the Li ions storage behaviours are experimentally investigated from the post morphologies of all the cycled electrodes, and theoretically studied by the COMSOL Multiphysics simulations and the first principles calculations. These results would shed light on the new strategy to design and exploit other high-performance Si based LIMBs. Illustration the merits of the unique patterned Si/TiN/Ge electrode configurations. [Display omitted] • Novel patterned Si/TiN/Ge anode for Li ion microbattery. • TiN interlayer favorably tailor the Li ions storage. • Improvement in patterned Si/TiN/Ge anode. • Systematic investigations in Li ion diffusion behaviors. [ABSTRACT FROM AUTHOR]

Relaxor ferroelectric 0.94Na0.5Bi0.5TiO3‐0.06BaTiO3‐modified antiferroelectric Pb0.99Nb0.02[(Zr0.57Sn0.43)0.94Ti0.06]0.98O3 ceramics, (1−x)PNZST‐x(BNT‐6BT), were prepared to acquire high energy storage and thermal stability properties. X‐ray diffraction and element mapping revealed that a solid solution between PNZST and BNT‐6BT occurs, and Ti cations enter the PNZST lattice, partly extruding Sn cations and leading to the formation of isolated SnO2 particles at the grain boundaries and a 0‐3 type composite structure. Such a composite structure helps to create deviatoric stress in the solid solution component. The BNT‐6BT content significantly influences the energy storage capacity, and the x = 0.2 composition renders optimal performance. The room‐temperature‐recoverable energy density and energy efficiency are 2.23 J/cm3 and 78%, respectively, at 260 kV/cm. Both parameters vary less than 6% within a temperature range of 25°C and 125°C. The improved energy storage and temperature stability indicate that the ceramics can potentially be applied in pulse power capacitors and that this relaxor‐modified antiferroelectric ceramic preparation method is a valuable reference for further optimizing the functional properties. [ABSTRACT FROM AUTHOR]

Unusual substitutional and interstitial solid solutions were observed in (1−x)Ba(Zr0.35Ti0.65)O3-xZnO thin films, where one Zn2+ cation substituted one B-site Zr4+/Ti4+ site and two Zn2+ cations substituted one A-site Ba2+ site simultaneously. Such a hybrid solid solution with an appropriate ZnO content remarkably increases both the electric breakdown strength (Eb) by widening the bandgap and the energy storage efficiency (η) by suppressing the hysteresis of the ferroelectric loop. As a result, the films with x = 0.2 show superior energy storage performance with a recoverable energy storage density (Wrec) of 130.3 J/cm3 and η of 89.1%. This work confirms the feasibility of forming an unconventional hybrid solid solution, which may shed light on further work on perovskite oxides with improved ferroic functionalities. [ABSTRACT FROM AUTHOR]

Developed ceramic capacitors with excellent recoverable energy storage density (W rec) and efficiency (η) are greatly desired for next-generation pulsed power devices but challenge as well. Herein, outstanding W rec of 5.2 J/cm3 and η of 82% are achieved in the PbO-doped fine grain Bi 0.25 Na 0.25 Sr 0.5 TiO 3 (BNST-P) based relaxor ferroelectric ceramics. The corresponding mechanism is that A-site Pb-doping increases maximum polarization and breakdown strength, and suppresses remnant polarization simultaneously. Meanwhile, the energy storage property possesses excellent temperature and frequency stability, and the variation of W rec and η is less than 5% within the range of 25–100 °C and 2–100 Hz. Encouragingly, superior charge-discharge performance with fast discharge speed t 0.9 of 24 ns and high power density P D of 296 MW/cm3 is obtained. These striking comprehensive results suggest BNST-P ceramics possess potential prospects for applications. [ABSTRACT FROM AUTHOR]

Solid solution ceramics of (1- x)Sr 0.75 Ba 0.25 Nb 2 O 6 - x PbZr 0.52 Ti 0.48 O 3 (x = 0−0.4) were prepared and investigated. The phase evolves from tungsten bronze for x = 0, coexisted tungsten bronze and pyrochlore at x = 0.3, to pyrochlore for x > 0.3. As the results, the ceramics show dramatically composition dependent microstructure and electrical property. The grain shape changes from anisotropic pillar-like with maximum length-diameter ratio of 3.3 at x = 0.2 to isotropic cubic-like for x > 0.2. At the same time, the maximum dielectric constant temperature tends to decrease with an exceptional increase at x = 0.3 due to the coexisted phases. Interestingly, the x = 0.3 ceramic endures ultrahigh breakdown strength of 340 kV/cm, which, together with enhanced polarization, results in maximum recoverable energy storage density of 3.0 J/cm3and energy storage efficiency of 81.5 % at room temperature. [ABSTRACT FROM AUTHOR]

(1- x)(Pb 0.97 La 0.02)(Zr 0.5 Sn 0.4 Ti 0.1)O 3 - x (Na 0.5 Bi 0.5) 0.94 Ba 0.06 TiO 3 (x = 0 ∼ 0.4) ceramics have been prepared and investigated. The ceramics consist of perovskite solid solution matrix and precipitated, isolated SnO 2 particle, resulting in 0–3 type composite structure. With increasing x value, the room temperature crystal structure of perovskite solid solution transforms from tetragonal to pseudocubic, therefore, the electrical property evaluates form robust antiferroelectric at x = 0, metastable antiferroelectric at x = 0.1, and then relaxor ferroelectric at x > 0.1. Moreover, the breakdown strength is enhanced due to the composite structure and reaches maximum value of 190 kV/cm at x = 0.2. Both the phase transition and enhanced breakdown strength are helpful to improve energy storage property, the x = 0.2 ceramic shows largest recoverable energy density w rec of 1.84 J/cm3, discharge efficiency η of 86.6 %. Especially, both w rec and η illustrates significantly improved thermal stability within 25−125 °C. [ABSTRACT FROM AUTHOR]

0.82[0.94Bi 0.5 Na 0.5 TiO 3 -0.06BaTiO 3 ]-0.18K 0.5 Na 0.5 NbO 3 : x ZnO (BNT-BT-KNN: x ZnO, x  = 0-0.40) relaxor composites were prepared and their electrical properties were investigated. The breakdown electric field increases with increasing ZnO content. For x  = 0 and x  = 0.40 samples, the maximum recoverable energy storage density is 0.74 J/cm 3 and 1.03 J/cm 3 while the maximum energy storage efficiency is 86.7% and 72.7% under the electric field of 9.0 kV/mm and 14.0 kV/mm, respectively. The recoverable energy storage density and efficiency of the composite vary less than 2.5% from 25 °C to 125 °C, which indicates temperature-insensitive energy storage performance. These results are discussed based on the ZnO-enhanced bulk resistivity and the ZnO-induced local electric field which suppresses the evolution of polar nanoregions. [ABSTRACT FROM AUTHOR]

Abstract: Despite high‐energy density and low cost of the lithium–sulfur (Li–S) batteries, their commercial success is greatly impeded by their severe capacity decay during long‐term cycling caused by polysulfide shuttling. Herein, a new phase engineering strategy is demonstrated for making MXene/1T‐2H MoS2‐C nanohybrids for boosting the performance of Li–S batteries in terms of capacity, rate ability, and stability. It is found that the plentiful positively charged S‐vacancy defects created on MXene/1T‐2H MoS2‐C, proved by high‐resolution transmission electron microscopy and electron paramagnetic resonance, can serve as strong adsorption and activation sites for polar polysulfide intermediates, accelerate redox reactions, and prevent the dissolution of polysulfides. As a consequence, the novel MXene/1T‐2H MoS2‐C‐S cathode delivers a high initial capacity of 1194.7 mAh g−1 at 0.1 C, a high level of capacity retention of 799.3 mAh g−1 after 300 cycles at 0.5 C, and reliable operation in soft‐package batteries. The present MXene/1T‐2H MoS2‐C becomes among the best cathode materials for Li–S batteries. [ABSTRACT FROM AUTHOR]

Lead-free ceramic-based dielectric capacitors with high-performance energy storage properties have become an emerging issue recently as a result of the applications in high-power and/or pulsed-power technologies. However, the trade-off between various parameters, such as maximum polarization P max , remnant polarization P r and dielectric breakdown strength E b , restricts the further improvement of the energy storage properties of dielectric ceramics. Herein, a synergistic optimization strategy via simultaneous enhancement of P max and E b and reduction of P r is adopted to achieve outstanding energy storage properties for Bi 0.9 La 0.1 FeO 3 -Ba 0.7 Sr 0.3 TiO 3 NaNb 0.85 Ta 0.15 O 3 relaxor ferroelectric ceramics, characterized by an ultrahigh recoverable energy density W rec of 15.9 J/cm3 and high efficiency η of 87.7%. The inborn gene of BiFeO 3 -based materials results in high P max and the improved relaxor behavior gives rise to a small P r value. In Particular, a very large value for E b is obtained by tailoring multiple intrinsic and extrinsic factors. These results demonstrate the reliability and feasibility of the multiple optimization strategy proposed in this work to develop novel dielectric ceramics for advanced energy storage applications. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Realizing stabilized antiferroelectric phase and enhanced relaxor behavior in (Na 1-3/2 x Bi 3/2 x)(Nb 1- x Mg x)O 3 ceramics. • The large E b of 78.3 kV/mm, ultrahigh W rec of 10.9 J/cm3 and high η of 83% were achieved in × = 0.06. • x = 0.06 exhibited superior frequency, fatigue, thermal stability and ultrafast discharge rate. Lead-free ceramic-based dielectric capacitors have attracted extensive investigation due to their potential applications in pulsed power devices. However, the main drawback of dielectric ceramics is the relatively low energy storage density. Herein, Bi3+ and Mg2+ with different ionic radius and valence are introduced into antiferroelectric NaNbO 3 matrix to form (Na 1-3/2 x Bi 3/2 x)(Nb 1- x Mg x)O 3 solid solutions, where the antiferroelectric phase is stabilized and the relaxor behavior is also improved. Of particular importance is that a large breakdown strength (E b) of 78.3 kV/mm, an ultrahigh recoverable energy density (W rec) of 10.9 J/cm3 and efficiency (η) of 83% are simultaneously achieved in (Na 0.91 Bi 0.09)(Nb 0.94 Mg 0.06)O 3 ceramic. Moreover, the energy storage properties of (Na 0.91 Bi 0.09)(Nb 0.94 Mg 0.06)O 3 ceramic also reveals superior frequency (1–100 Hz), cycling (100–105) and thermal (30°C–100°C) stability, together with the ultrafast discharge rate (<25 ns). These results demonstrate the NaNbO 3 -based lead-free relaxor antiferroelectric ceramics is a promising candidate for energy storage application. [ABSTRACT FROM AUTHOR]

● PLZST: x SnO 2 composite ceramics were prepared by solid state reaction. ● The composite structure had significant effects on microstructures and electrical properties. ● The optimal composition of x = 0.2 showed high energy storage density of 2.38 J/cm3. Constructing composite structure is an effective way to improve dielectric energy storage properties. However, ionic diffusion between composite members is generally inevitable, which mixes the effects of solid solution with composite structure on property to some extent. To exclude the ionic diffusion effect as much as possible, antiferroelectric (Pb 0.97 La 0.02)(Zr 0.5 Sn 0.4 Ti 0.1)O 3 (PLZST) was sintered at a relatively high temperature to precipitate SnO 2 particles, then more SnO 2 were introduced to from (1- x)PLZST: x SnO 2 (x = 0–0.25) composite. The results showed that composite structure had significant effects on microstructures and properties with changed lattice parameter, decreased grain size, increased Curie temperature, suppressed antiferroelectric property, and enhanced electric breakdown strength. The optimal composition of x = 0.2 showed high energy storage density of 2.38 J/cm3. This work provides a robust platform to investigate the effect of composite microstructure on electrical properties, which is helpful for further developing high performance composite materials. [ABSTRACT FROM AUTHOR]