Relaxor ferroelectric ceramics are promising energy-storage candidates for high-power electronic systems owing to their high energy density and fast charge-discharge speed. However, achieving ultrahigh energy density still poses challenges due to the inherently inverted coupling relationship between polarization (P) and breakdown electric field (Eb). Here, we propose a high-entropy strategy to decouple polarization from breakdown electric field. The high-entropy design exerts a triple effect, which involves flattening electronic band to restrict the transport of charge carriers, driving the formation of core-shell heterostructure to suppress electrical breakdown, and stabilizing polymorphic polar phases to promote polarization rotation. The triple synergy effect led to an ultrahigh Eb and a maximized polarization disparity (ΔP = Pm - Pr). As a result, the high-entropy ceramics exhibit an ultrahigh recoverable energy density (Wrec) of 10.23 ± 0.99 J/cm3 and a satisfactory efficiency (η) of 85.44% ± 3.34%, alongside good cycling reliability and temperature stability. This work provides an innovative design paradigm for achieving excellent energy storage performance of dielectric capacitors.

As demands for high-performance capacitors in high-temperature applications such as electrified transport and pulsed power systems grow, polymer dielectrics with both high discharge energy density (U-d) and superior thermal stability are increasingly needed. In this work, we introduce an interlayer-directed multilevel trap engineering approach to create all-organic sandwich-structured polymer composite films through a one-step dip-coating and hot-pressing process. A high-electron-affinity organic semiconductor, 1,4,5,8-naphthalene tetracarboxylic dianhydride (NTCDA, C14H4O6), is incorporated into poly(vinylidene fluoride-hexafluoropropylene) (P(VDF-HFP)) and coated onto a central poly(ethylene terephthalate) (PET) layer, which is then sandwiched between two outer PET films. The energy band offset between NTCDA and P(VDF-HFP) creates multilevel deep traps, while the interlayer interfaces introduce effective carrier barriers. This synergistic trap-barrier effect significantly suppresses charge transport and leakage current, resulting in enhanced breakdown strength (E-b) (similar to 678.6 MVm(-1)) and excellent energy storage performance (ESP) (U-d approximate to 8.2 Jcm(-3), efficiency (eta) approximate to 94.3 %) at 25 degrees C. At 125 degrees C, a high U-d of 6.4 Jcm(-3) is retained. This research offers an effective approach to develop polymer dielectrics that combine thermal stability with high efficiency for cutting-edge energy storage uses.

Dielectric capacitors offering ultrafast charge-discharge capability and superior reliability are essential for advanced electronic systems, but achieving both high energy density and efficiency within simple and eco-friendly compositions remains a great challenge. Here, guided by machine learning, we achieve high-efficiency and thermally stable capacitive energy storage in strontium titanate-based ceramics. Through synergistic local structural engineering and optimized fabrication process, the materials exhibit enhanced polarization, reduced hysteresis loss, and improved breakdown strength. The designed materials deliver an ultrahigh energy density of 10.69 J cm-3 with a near-ideal efficiency of ∼97% and a record high figure of merit of 392 J cm-3 at room temperature, and retains high performance at 150°C with a figure of merit of 152 J cm-3 and an efficiency of ∼94%. This remarkable performance arises from the incorporation of Bi3+ ions with high polarizability at the A-sites of strontium titanate quantum paraelectrics, which breaks structural symmetry and induces lattice and octahedral distortions, leading to the formation of nanoscale polar clusters with highly dynamic fluctuations. These findings establish a compositionally simple, environmentally benign pathway for developing dielectrics with superior energy storage capability and thermal stability, offering new opportunities for high-performance capacitive energy storage systems.

Multilayer ceramic capacitors (MLCCs) have become the core materials in advanced electronics and power equipment thanks to the excellent functional characteristics, including energy storage, filtering, and coupling. However, the next-generation electronic devices place higher demands on the energy storage performance for MLCCs. This study demonstrates that the directional regulation of gradient polarization coupling (GPC) constitutes an effective approach to achieving a giant energy storage density. With the guidance of theoretical predictions, we propose a high configurational entropy (HCE) strategy in NaNbO3-based (NN) multilayer ceramic capacitors to constructing the alternating multipolar nanodomains. Alternately distributed weakly polar and strongly polar domains with embedding nonpolar nanoclusters possess the effective gradient coupling of polarization. Polymorphic polarization coupling realizes the dynamic orientation of local nanoclusters to drive the orientation of the overall electric dipoles, which could reduce hysteresis loss while maintaining high polarization strength. As a consequence, the NN-20H MLCCs achieve a recoverable energy storage density of 20.4 J/cm3 and an ultrahigh breakdown strength of 1680 kV/cm, which demonstrates great advancement in reported lead-free ceramic capacitors. This work illustrates the GPC strategy to advance novel insights for next-generation MLCCs with high energy storage performance.

Dielectric energy storage ceramics with both superior energy storage performance (ESP) and simple chemical compositions are highly in demand for dielectric capacitors practical applications. However, advancing excellent ESP commonly demands highly complex chemical components, which is a challenging task that remains unresolved. Here, via integrating the component engineering and process engineering, we achieve substantially improved energy storage density Wrec (∼9.21 J/cm3) and efficiency η (∼85.4%)under 940 kV/cm in SrTiO3-based ceramic with a simple chemical composition (two doped elements), showcasing tremendous potential for next-generation energy-storage device. The achieved performance merits are credited to multiple synergy effects: local polar structure concomitant with ultrasmall and highly dynamic polar nano-regions, improved electrical homogeneity, reduced grain size, and suppressed oxygen vacancies. Therefore, our proposed approach offers a design freedom to develop high-performance dielectrics with a simple composition for practical implementations of dielectric capacitors.

Overcoming the trade-off between multiphase coexistence and phase transformation in piezoelectrics remains a critical challenge for achieving high and stable piezoelectric performance over a broad temperature range. Here, we resolve this long-standing dilemma by constructing a continuous phase transition through multilayer ceramic texture engineering. Specifically, two types of (K,Na)NbO3-based piezoelectric ceramics with distinct polymorphic phase boundary (PPB) features are physically composed. The composite ceramics exhibit hierarchic phase and domain structures, particularly a continuous phase transition, enabling outstanding piezoelectric performance and thermal stability across a wide temperature range. As a result, the multilayer composite ceramics prepared in this work demonstrate excellent room-temperature piezoelectric properties, with a piezoelectric coefficient (d33) ∼ 420 pC N-1 and an inverse piezoelectric coefficient (d33*) ∼ 600 pm V-1. More importantly, within the temperature range of 25°C-100°C, the variation in d33 and d33* values is merely 2%. This work establishes a continuous phase transition-driven paradigm for enhancing piezoelectric thermal stability, demonstrating universal potential to decouple the constraints imposed by multiphase coexistence and phase transformation in next-generation piezoelectric materials.

Polymer film capacitors are essential components in modern electronics due to their superior performance. However, their limited high-temperature stability hinders applications in demanding fields like electric vehicles and aerospace. While nanofiller doping has been extensively explored to enhance high-temperature performance, the inherent filler aggregation driven by van der Waals forces, hydrogen bonding, and electrostatic interactions remains a critical yet overlooked challenge, leading to heterogeneous dielectric response, compromised breakdown strength, and mechanical deterioration. Wide-bandgap magnesium oxide nanoplates (MgO NPLs) are synthesized via hydrothermal method and incorporated as fillers at ultralow loading into promising polyetherimide (PEI) matrix, followed by fabrication of tri-layer films through combined solution-casting and hotpressing. An innovative concept of precisely tailoring filler distribution in polymer matrix has been proposed for the first time to effectively prevent nanofiller aggregation and charge accumulation, achieving uniform electric field distribution while minimizing interfacial dielectric mismatch and local field distortion. Consequently, the tri-layer composite dielectric maintains exceptional energy storage characteristics even under extreme high-temperature conditions. The maximum discharge energy density (Ud) reaches 7.82 J/cm3 with an efficiency (eta) of 87.47 % at 150 degrees C. Remarkably, at 200 degrees C, the composite delivers an impressive Ud of 4.17 J/ cm3 with eta above 90 %, representing a tenfold improvement over pristine PEI and surpassing currently available commercial polymer dielectrics, newly developed synthetic polymers, and polymer composites. The proposed strategy of precisely tailoring the filler distribution demonstrates universal applicability across various polymer systems and diverse nanofillers, establishing a new paradigm for developing high-temperature-stable polymer dielectrics.

(K,Na)NbO3 (KNN)-based ceramics are considered among the most promising lead-free piezoelectric materials, despite the numerous challenges encountered during the sintering process. To better understand the sintering behavior of KNN-based ceramics, we adopted an innovative approach combining powder activity modulation with a two-step sintering process, successfully obtaining samples with diverse grain morphologies in the KNNTa-BNN ceramics, including uniformly distributed small grains, large grains, and even single-crystalline-like oversized grains. Comprehensive structural analysis reveals that the formation of large grains is associated with the abnormal grain growth. In this process, surface activity factors of calcined powder serve as the primary determinants of grain evolution pathways, while elemental segregation acts as a superimposed perturbing factor. Owing to the differences in T phase content and internal stress between large and small grains, Raman spectroscopy technology was employed to effectively distinguish them. The increase in grain size leads to a rise in long-range ordered non-180° domains, significantly enhancing the extrinsic contribution. As a result, the 6Ta ceramics with appropriately large grain sizes (∼31.65 μm) exhibit excellent comprehensive piezoelectric performance (d33 ∼ 315 pC/N, TC ∼ 390 °C), making it highly competitive among KNN-based ceramics. When the single-crystalline-like oversized grains were developed, the piezoelectric performance (d33 > 500 pC/N) can be further enhanced. This work enriches the grain growth theory of KNN-based ceramics and offers a potential route to high-performance single crystals.

Benefiting from ultrafast charge-discharge capability, high power density, and excellent cycling stability, dielectric capacitors are promising for advanced pulsed power and electronic applications. However, their performance is still limited by the intrinsic trade-off between recoverable energy density (W-rec) and efficiency (eta). Here, a series of lead-free relaxor ferroelectric ceramics with the composition (1-x)(0.75Bi(0.5)Na(0.5)TiO(3)-0.25BaTiO(3))-xBa(Mg1/3Ta2/3)O-3 ((1-x)BNTBT-xBMT) were designed via compositional engineering. The incorporation of BMT induces enhanced relaxor behavior, reduced domain size, and suppressed polarization hysteresis, which collectively contribute to improved energy storage performance. As a result, the optimized composition (x = 0.08) exhibits a high W-rec of 8.92 J/cm(3) and an efficiency of 93.42% under 700 kV/cm. In addition, excellent thermal stability (20-120 degrees C), frequency stability (1-100 Hz), and outstanding cycling endurance (10(5) cycles) are achieved, together with a high power density (similar to 350 MW/cm(3)) and ultrafast discharge rate (t(0).(9) approximate to 35 ns). This work provides a viable strategy for designing high-performance dielectric materials for energy storage applications.

Simultaneously achieving sensitive lattice-distortion detection and high capacitive energy storage in dielectric ceramics is critically demanded yet challenging for fail-safe aerospace systems. Herein, a novel high-low valence co-substitution strategy is designed for a NaNbO3-based relaxor ferroelectric with the composition (1-x)[0.85(Na0.94Yb0.01Tm0.01)NbO3-0.15(Bi0.5Na0.5)TiO3]-x(Ba0.5Sr0.5)(Sn0.5Hf0.5)O3. The severe valence imbalance triggers a spontaneous Bi3+/5+ self-compensation mechanism, driving Bi migration from A- to B-site. This unique configuration induces intense lattice distortion, which substantially lowers the energy barrier for splitting Tm3+ 4f orbitals and activates a new electronic state (3F'2|3). Consequently, a direct correlation between lattice distortion and rare-earth luminescence is established, enabling real-time assessment via photoluminescence peak splitting. Concurrently, Yb3+/Tm3+ co-doping bestows anomalous thermally enhanced fluorescence for temperature sensing. Furthermore, the dual-site Bi substitution facilitates a local coexistence of polymorphic relaxor phases (rhombohedral-orthorhobic-tetragonal-cubic), yielding a high breakdown strength of 785 kV cm-1 and an outstanding recoverable energy density of 13.73 J cm-3 with 94.24% of efficiency. This work provides a paradigm for developing multifunctional materials capable of atomic-resolution operando monitoring and superior energy storage in extreme environments.

Advanced electronic systems rely heavily on the development of high-performance dielectric ceramic capacitors. However, achieving simultaneous improvements in both recoverable energy density (Wrec) and efficiency (η) under moderate electric fields remains a significant challenge for practical applications. In this study, we engineer a dual-phase perovskite structure in (Bi0.5Na0.5)TiO3-based ceramics through an in situ phase separation to address this issue. The resulting grain-separated dual-phase ceramics exhibit two interacting relaxor phases with distinct nanoscale polar structures and heterogeneous stress, resulting in large polarization, low polarization hysteresis, and delayed polarization saturation. Additionally, a relatively high breakdown strength is achieved through an increased bandgap, reduced oxygen vacancy concentration, and enhanced electrical homogeneity, complemented by the dual-phase structure, which increases the length and the meandering of the electrical-tree propagation path. As a result, the optimized dual-phase ceramic exhibits exceptional overall performance, with a high energy-storage coefficient of 0.014 µC/cm2 accompanied by a large Wrec of 5.84 J/cm3 and an ultrahigh η of 92% under 420 kV/cm, along with excellent stability, and robust charge-discharge characteristics. This study presents a practical strategy for designing high-performance dielectric energy-storage ceramics that operate under moderate electric fields, providing valuable insights for tailoring functional properties in ferroelectrics.

Photoelectrochemical (PEC) systems provide a sustainable approach to producing value-added chemicals by synergizing photo- and electrochemical processes. Beyond conventional strategies that focus on tuning intrinsic material properties, external field modulation emerges as a promising avenue for steering chemical reactions. Herein, a bifunctional ferroelectric catalyst Ba0.7Sr0.3TiO3 (BSTO) is demonstrated on both photoanode and cathode to concurrently promote water oxidation and two-electron oxygen reduction reaction (2e-ORR). BSTO-coated α-Fe2O3 is first selected as a model photoanode with enhanced PEC water oxidation performance upon controlled electric poling. Mechanistic studies indicate that ferroelectric polarization effectively tunes the band bending at the Fe2O3/BSTO interface, thereby facilitating charge separation. The general applicability of this strategy is further demonstrated with other metal oxide photoanodes, including TiO2 and BiVO4. On the cathode side, ferroelectric polarization induces a transition of the O2 adsorption configuration from the Yeager- to the Pauling-type, which not only accelerates interfacial charge transfer kinetics but also favors the 2e-ORR pathway, resulting in an increased H2O2 production rate. These findings highlight ferroelectric modulation as a versatile strategy for the design of high-performance (photo)electrocatalytic systems.

Lead-free BF-based piezoelectric ceramics are attracting much interest in high-temperature piezoelectric systems owing to their high Curie temperature (Tc) and good thermal stability. However, their development toward integration in piezoelectric devices has been severely impeded by unsatisfied overall properties. Herein, a template reinforcement texture process was proposed to fabricate highly textured BF-based piezoceramics with exceptional performance. The plate-like BaTiO3 templates undergoes annealing treatment to enhance mechanical properties, enabling them to maintain shape integrity and function normally as seed crystals. Consequently, the resultant lead-free BF-based textured piezoelectric ceramics exhibit ultrahigh texture degree (F001 = 97.0%) and exceptional piezoelectric performance (d33 = 303 ± 10 pC/N, Tc = 512°C, kp = 43.4%). Multiscale structural analysis and phase-field simulation revealed that enhanced piezoelectric performance could be attributed to the large lattice distortion, formed engineered "4R" and "1T" domains configuration, precisely controlled rhombohedral/tetragonal (R/T) phase ratio, and induced nanodomain structures with decreased domain wall energy. Moreover, the piezoelectric circular diaphragm prepared based on the texture ceramic exhibits excellent energy harvesting performance in the temperature range of 25°C-250°C. Therefore, this work provides a novel and effective method for enhancing the comprehensive piezoelectric performance of lead-free BF-based ceramics.

Development of high-performance lead-free AgNbO3 (AN)-based antiferroelectrics (AFEs) have emerged as promising candidate for high-power energy-storage capacitors. Routine trial-and-error method in enhancing energy-storage density (Wrec) and efficiency (η) encounters great challenges since extensive latent space are explored for composition screening. Using machine learning (ML) algorithms, a two-layer stacking framework termed as SS-PAN (stacking strategy for predicting AN-based ceramics) is proposed here for designing high-performance AN-based AFEs. This framework achieves a high R2 score of 0.82 through cross validation and outperforms individual ML model. The predicted composition represented by Li0.01Ag0.99Nb0.5Ta0.5O3, possesses a quasi-linear P-E loop and an ultrahigh Wrec of 16.6 J cm-3 and η of 92.6% with an excellent figure of merit of 224.3 J cm-3 is achieved at electric field of 108 kV mm-1 in MLCC. Based on SHapley Additive exPlanations analysis, high prediction accuracy is enabled by precisely selecting features of tolerance factor and electron affinity of B-site element. Notably, local structure for Li0.01Ag0.99Nb0.5Ta0.5O3 composition is thoroughly decoded by STEM and DFT calculations, where highly polar short-range antiferroelectric nanodomains with strong localized dipole moments are induced by Li/Ta co-doping. This work imparts a potent potential of data-driven methodology for seeking emergent relaxor AFEs for advanced dielectric capacitor applications.

ABSTRACT Photocatalysis involving proton‐coupled electron transfer offers a sustainable route for solar‐to‐chemical energy conversion, yet its efficiency and selectivity hinge on synergistically managing the photon harvesting, electron transfer, proton supply, and reactant activation. Herein, a piezoelectric S‐scheme heterojunction is constructed from Sb single atoms embedded carbon nitride and oxygen vacancy‐rich BiOIO 3 with enhanced piezoelectricity. The formed strong interfacial chemical bonds facilitate rapid and directed electron transfer between the components under the piezoelectric field. Moreover, the atomically dispersed Sb‐based frustrated Lewis pair features an electron‐deficient Sb single atom as the Lewis acid, whose acidity is enhanced by axial O coordination‐induced electron delocalization, while the adjacent electron‐rich N atom acts as the Lewis base. Such spatial and electronic structure, along with surface Brønsted acid sites, collectively establish a multi‐synergy that enhances photon absorption through the formation of hybrid energy levels, optimizes O 2 adsorption energy in the Pauling‐type configuration, and enables spontaneous hydrogenation with continuous proton supply. The heterostructure achieves a high H 2 O 2 yield rate of 5.51 mmol h −1 g −1 and selectivity of up to 99.1% without sacrificial agents. This work demonstrates a pathway for green chemical synthesis via multifield coupling and atomic‐level interface regulation.

With the trend toward miniaturized and intelligent infrared systems, high-performance light source chips featuring a high modulation depth and rapid thermal response have emerged as key components for advancing interdisciplinary applications. In this study, a dual-band infrared source chip featuring a suspended membrane structure on a silicon-on-insulator substrate is reported. The suspended polysilicon emissive layer was prepared via high-concentration boron doping and micro-nano processing techniques. Relative to a closed membrane configuration, the suspended structure yields superior thermal and optical characteristics including a thermal response time of 36 ms to reach 450 degrees C, a modulation depth of 50% at 60 Hz, and dual-band emission centered at 3.6 and 9.54 mu m. Structural-property correlation analysis reveals that the specific infrared emission signatures are intrinsically linked to the lattice microstructure. In particular, the 3.6 mu m emission is attributed to the stretching vibrations of hydrogen-bridged bonds and Si-H bonds localized at oxygen vacancies within the surface SiO2 layer. In addition, the 9.54 mu m peak originates from the coupling between the SiO2 network bending modes and the localized vibrational modes of Si-B bonds introduced by boron doping. Furthermore, the suspended membrane architecture plays a critical role in enhancing modulation performance by geometrically confining heat, thereby suppressing lateral thermal diffusion and reducing thermal capacitance. These insights establish a direct mapping between micro/nano-structural design and optoelectronic performance, offering a robust theoretical framework for developing high-efficiency infrared emitters for gas sensing and photodetection applications.

The low energy density, inefficient operation, and thermal instability of polymer dielectrics hinder the deployment of film capacitors under harsh environmental conditions. Interface engineering has emerged as a powerful strategy to introduce charge traps or construct interfacial barriers, thereby regulating carrier dynamics and enhancing energy storage. Here, we propose a multilevel heterointerface engineering strategy that integrates boron nitride and barium niobate nanosheets through lattice interlocking. The large work-function offset and bandgap contrast induce interfacial band bending and a built-in electric field, forming a complementary trap-barrier network that guides, blocks, and confines charge carriers. This design effectively suppresses charge injection and mobility, enhances interfacial polarization, and mitigates the propagation of breakdown pathways. Consequently, BNO@BN/PEI composites achieve exceptional energy storage performance, delivering 9.02 J cm-3 (η = 92%) at room temperature and sustaining 6.1 J cm-3 (η ≈ 90%) at 150°C, while still preserving 4.6 J cm-3 at 200°C. First-principles calculations and finite element simulations further validate the structural and functional superiority of the multilevel heterointerface. This work establishes multilevel heterointerface engineering as a generalizable paradigm for breaking the trap-barrier trade-off in conventional dielectric design and paves the way for next-generation high-energy-density and thermally robust polymer capacitors.

Despite the preliminary successes of piezoelectric catalysis in environmental protection and biomedical fields, the challenge persists in manufacturing piezoelectric catalysts on a large scale that possesses both high degradation efficiency and affordability. In this work, 0.67BiFe0.98Al0.02O3-0.33BaTiO3 (BFA0.02-BT) ceramic powders were used as the substrate material; then, g-C3N4 and Cu were combined to prepare BFA0.02-BT/g-C3N4/Cu Ⅱ-type heterojunction piezoelectric catalyst. The addition of g-C3N4 enhanced the optical band gap from 2.17 to 2.41 eV, and Cu loading increased both the electron density of the heterostructure and the highly reactive ·O2−. Furthermore, a maximum inverse piezoelectric constant d33* = 99.5 pm/V as well as a phase reversal hysteresis loop of approximately 180° were observed in 3BFA0.02-BT/2 g-C3N4/3.8Cu, reflecting the good piezoelectric characteristic. The increased reactive ·O2−, higher carrier concentration, and the suitable band gap contributed to the excellent catalytic activity. The synergistic effect of piezoelectric and integrated heterojunction promoted the effective separation of photo-generated charges, as well as restrained of the recombination of holes and electrons. The degradation rate (k) of 3BFA0.02-BT/2 g-C3N4/3.8Cu composites against rhodamine B (RhB) dye, levofloxacin (Lev), and oxytetracycline (OTc) antibiotics was 0.47 min−1, 0.08 min−1 and 0.02 min−1, which was more than three times higher than that of reported BFO-based catalyst. This work presented a piezoelectric catalyst with high degradation efficiency, which was expected to be applied to the pollution of organic substances and antibiotics.

Environmentally friendly ferroelectric thin films are of extensive interest for dielectric energy storage capacitors, driven by the ongoing miniaturization and integration of advanced electronic systems. However, achieving simultaneously high energy density and efficiency under elevated electric fields remains a formidable challenge. Herein, a rationally designed, La-doped pyrochlore Bi2Ti2O7-based thin-film system Bi2-xLaxTi1.95Fe0.05O7 (BLTFx) is developed, demonstrating pronounced relaxor characteristics and exceptional energy-storage performance. Synergistic A-site La3+ and B-site Fe3+ doping engineering structurally stabilizes the metastable pyrochlore phase, effectively suppress grain growth, and homogenize the grain-size distribution. These structural modulations dynamically disrupt the long-range ferroelectric order, thereby simultaneously enhancing the reversible polarization response, mitigating hysteresis loss, and substantially elevating the breakdown strength. Consequently, the optimized BLTF-0.25 thin film achieves an ultrahigh recoverable energy density of 113.1 J/cm3 along with efficiency of 79.3% under 4409.6 kV/cm. Furthermore, the film exhibits outstanding electrical fatigue endurance and robust thermal stability. This work provides a highly effective compositional and microstructural design paradigm for pyrochlore pyrochlore-based dielectrics toward next-generation high-performance dielectric energy-storage capacitors.