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As one of the important electronic components, the dielectric capacitors for energy storage applications have been extensively studied in recent years. Among various dielectric materials, the perovskite oxide Bi0.5Na0.5TiO3‐based ceramics have become promising candidates due to their high polarization, dielectric tunability, environment‐friendly composition, and so forth. Herein, the relaxor ferroelectric ceramics of Bi0.5Na0.5TiO3–SrTiO3–Bi(Mg0.5Zr0.5)O3 were prepared via solid‐state reaction method. The sample with optimal composition not only retains the high polarization by introducing Bi3+ ions, but also achieves the reduced remanent polarization by enhancing relaxor behavior and the promoted electric breakdown strength by the grain size refinement. Accordingly, a high recoverable energy density of 8.3 J/cm3 under 450 kV/cm and the superb charge/discharge properties (current density CD = 1200 A/cm2, power density PD = 150 MW/cm3, charge/discharge time t0.9 = 0.15 µs) are achieved, revealing great prospect in energy storage applications. [ABSTRACT FROM AUTHOR]

Bismuth sodium titanate (Bi0.5Na0.5TiO3)-based relaxor ferroelectric ceramics have received ever-increasing interest for their potential application in dielectric capacitors owing to their sterling energy storage capability. Herein, the perovskite end-member Ba(Fe0.5Nb0.5)O3 (BFN) was incorporated into 0.7Bi0.5Na0.5TiO3-0.3SrTiO3 (0.7BNT-0.3ST) ceramics to improve the relaxor characteristics and refine the grain, leading to slim polarization–electric field (P–E) hysteresis loops and enhanced electric breakdown strength. Particularly, the 0.85(0.7BNT-0.3ST)-0.15BFN ceramics achieved a high recoverable energy density of 5.7 J/cm3 and a high energy storage efficiency of 86.4% under a moderate electric field of 390 kV/cm. Additionally, remarkable stability in frequency, cycling, and temperature and excellent charge/discharge behavior were achieved at the same time. The above findings reveal that BFN-modified BNT-ST ceramics display greatly improved comprehensive energy storage properties, making them promising candidates in the field of electrostatic energy storage. [ABSTRACT FROM AUTHOR]

An electrostatic capacitor has been widely used in many fields (such as high pulsed power technology, new energy vehicles, etc.) due to its ultrahigh discharge power density. Remarkable progress has been made over the past 10 years by doping ferroelectric ceramics into polymers because the dielectric constant is positively correlated with the energy storage density. However, this method often leads to an increase in dielectric loss and a decrease in energy storage efficiency. Therefore, the way of using a multilayer structure to improve the energy storage density of the dielectric has attracted the attention of researchers. Although research on energy storage properties using multilayer dielectric is just beginning, it shows the excellent effect and huge potential. In this review, the main physical mechanisms of polarization, breakdown and energy storage in multilayer structure dielectric are introduced, the theoretical simulation and experimental results are systematically summarized, and the preparation methods and design ideas of multilayer structure dielectrics are mainly described. This article covers not only an overview of the state‐of‐the‐art advances of multilayer structure energy storage dielectric but also the prospects that may open another window to tune the electrical performance of the electrostatic capacitor via designing a multilayer structure. [ABSTRACT FROM AUTHOR]

Excellent energy storage performance of dielectric capacitors is highly desired in all kinds of energy storage devices. In this study, Sr(Sc0.5Nb0.5)O3 was introduced to enhance the energy storage properties of (Bi0.47La0.03Na0.5)0.94Ba0.06TiO3 (BLNBT) ceramics. All ceramic samples were sintered densely, and the phase structure, microstructure, dielectric and ferroelectric properties were then systematically investigated. Two distinct dielectric anomaly peaks, which are detected from the dielectric properties as a function of temperature, suggest not only a phase transition, but also indicate typical relaxor features. The breakdown strength is significantly improved, and the polarization versus electric field hysteresis loops become slim with the increasing content of SSN. The optimum energy storage performance is achieved in 0.85BLNBT–0.15SSN ceramic with the recoverable energy density of 1.83 J/cm3 and energy efficiency of 82.32% under a moderate electric field of 185 kV/cm. The excellent energy storage performance of 0.85BLNBT–0.15SSN ceramic makes it a promising candidate material for advanced pulsed power capacitors. [ABSTRACT FROM AUTHOR]

As one of the important electronic components, the dielectric capacitors for energy storage applications have been extensively studied in recent years. Among various dielectric materials, the perovskite oxide Bi0.5Na0.5TiO3‐based ceramics have become promising candidates due to their high polarization, dielectric tunability, environment‐friendly composition, and so forth. Herein, the relaxor ferroelectric ceramics of Bi0.5Na0.5TiO3–SrTiO3–Bi(Mg0.5Zr0.5)O3 were prepared via solid‐state reaction method. The sample with optimal composition not only retains the high polarization by introducing Bi3+ ions, but also achieves the reduced remanent polarization by enhancing relaxor behavior and the promoted electric breakdown strength by the grain size refinement. Accordingly, a high recoverable energy density of 8.3 J/cm3 under 450 kV/cm and the superb charge/discharge properties (current density CD = 1200 A/cm2, power density PD = 150 MW/cm3, charge/discharge time t0.9 = 0.15 µs) are achieved, revealing great prospect in energy storage applications. [ABSTRACT FROM AUTHOR]

High recoverable energy density (10 J cm−3) multilayers have been fabricated from lead-free 0.61BiFeO 3 -0.33(Ba 0.8 Sr 0.2)TiO 3 -0.06La(Mg 2/3 Nb 1/3)O 3 ceramics. High breakdown strength > 730 kV cm-1 was achieved through the optimisation of multilayer processing to produce defect-free dielectric layers 7 μm thick. Excellent temperature, frequency, fatigue stability and fast charge-discharge speed were observed in the multilayer, critical for their potential use in power electronics. [ABSTRACT FROM AUTHOR]

[Display omitted] • Novelty in our study can be listed below: • Two-step-sintered MLCCs achieve a high W rec of 7.8 J cm−3 at 370 kV/cm. • Two-step-sintered MLCCs display outstanding stability (10 ∼ 180 °C, ΔW rec < 10 %). • Two-step sintering can refine the grains of NBT-based MLCCs and improve their E BD. Dielectric materials for multilayer ceramic capacitors (MLCCs) have been widely used in the field of pulse power supply due to their high-power density, high-temperature resistance and fatigue resistance. However, the low energy storage density is one of most critical issues hindering their miniaturization and integration development in cutting-edge technologies. In this manuscript, Na 0.5 Bi 0.5 TiO 3 -based MLCCs with improved energy storage properties were fabricated via composition modification and sintering process improvement. The introduction of BiMg 0.5 Hf 0.5 O 3 weakens the ferroelectricity of 0.94Na 0.5 Bi 0.5 TiO 3 -0.06BaTiO 3 , while ensures high saturation polarization, delays polarization saturation, and low residual polarization, improving energy storage efficiency. Specifically, we adopted a two-step sintering process, by which the grain size of MLCCs sintered reduces by 60 %, the dielectric breakdown field strength increases by 33 %. The energy storage density reaches 7.8 J cm−3, 77 % higher than the MLCCs fabricated by traditional one-step sintering method. Moreover, the energy storage density changes by less than 10 % in a wide temperature range of 10 ∼ 180 °C. This study confirms that two-step sintering can also be applied to the preparation of Na 0.5 Bi 0.5 TiO 3 -based MLCCs and provides a way to improve the energy storage performance of lead-free MLCCs, and benefits to the application of MLCCs as high voltage capacitors. [ABSTRACT FROM AUTHOR]

Abstract Excellent electric energy discharging efficiency and fatigue resistance are two critical factors in high energy storage capacitor for electronic device and high-power system with fast charging-discharging speed. Here, we report on designing and preparing the thick films of BaZr 0.2 Ti 0.8 O 3 (BZT20) bilayer ceramics (BLCs) (∼40 μm in thickness) using a tape casting method. In this ABO 3 -structured perovskite ceramics, the B position of Ti was occupied by 20 mol% Zr atoms, which leads to order-disordering and random fields in the single phase with both the tetragonal (space group P 4 mm) and rhombohedral (space group m-3m). And therefore, the relaxors possess a heterogeneous polar state at the nanoscale and their long-range domains are disrupted. Consequently, a non-hysteretic arc-shaped unipolar polarization-electric frield loop (P-E loop) in which the curve obtained under a considerable high electric field of 80 MV m−1 and the curve under depolarization are overlaped. As such, a large energy storage density (U e) of ∼6.2 J cm−3 with the discharging efficiency of ∼98% and a considerable fatigue resistance over 22 k cycles at a wide temperature range from 253 to 393 K (−20 °C–120 °C) are obtained. The attractive electric performance of this BLCs films demonstrates that this sort of relaxor ceramics is one of promising materials for capacitors with little calorigenic electronic power areas. Highlights • Relaxor BaZr 0.2 Ti 0.8 O 3 bilayer ceramics are prepared using a tape casting method. • Non-hysteretic P-E loop curve under polarization overlaps the depolarization part. • A large energy density of ∼6.2 J cm−3 with the efficiency of ∼98% is obtained. • A considerable fatigue resistance of 22 k cycles at −20 °C to 120 °C is obtained. [ABSTRACT FROM AUTHOR]