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Dielectric ceramic capacitors with ultrahigh power densities are fundamental to modern electrical devices. Nonetheless, the poor energy density confined to the low breakdown strength is a long-standing bottleneck in developing desirable dielectric materials for practical applications. In this instance, we present a high-entropy tungsten bronze-type relaxor ferroelectric achieved through an equimolar-ratio element design, which realizes a giant recoverable energy density of 11.0 J·cm−3 and a high efficiency of 81.9%. Moreover, the atomic-scale microstructural study confirms that the excellent comprehensive energy storage performance is attributed to the increased atomic-scale compositional heterogeneity from high configuration entropy, which modulates the relaxor features as well as induces lattice distortion, resulting in reduced polarization hysteresis and enhanced breakdown endurance. This study provides evidence that developing high-entropy relaxor ferroelectric material via equimolar-ratio element design is an effective strategy for achieving ultrahigh energy storage characteristics. Our results also uncover the immense potential of tetragonal tungsten bronze-type materials for advanced energy storage applications. The authors present an equimolar-ratio element high-entropy strategy for designing high-performance dielectric ceramics and uncover the immense potential of tetragonal tungsten bronze-type materials for advanced energy storage applications. [ABSTRACT FROM AUTHOR]

PbZrO3 has been broadly considered as a prototypical antiferroelectric material for high-power energy storage. A recent theoretical study suggests that the ground state of PbZrO3 is threefold-modulated ferrielectric, which challenges the generally accepted antiferroelectric configuration. However, such a novel ferrielectric phase was predicted only to be accessible at low temperatures. Here, we successfully achieve the room-temperature construction of the strongly competing ferrielectric and antiferroelectric state by strain-mediated phase separation in PbZrO3/SrTiO3 thin film. We demonstrate that the phase separation occurs spontaneously in quasi-periodic stripe-like patterns under a compressive misfit strain and can be tailored by varying the film thickness. The ferrielectric phase strikingly exhibitsa threefold modulation period with a nearly up-up-down configuration, which could be stabilized and manipulated by the formation and evolution of interfacial defects under applied strain. The present results construct a fertile ground for further exploring the physical properties and applications based on the novel ferrielectric phase. There is a desire to know how the threefold ferrielectric coexists with the antiferroelectric phase. Here, the authors realize a threefold-modulated ferrielectric phase regulated by strain-mediated phase separation in PbZrO3 thin film. [ABSTRACT FROM AUTHOR]

Bismuth layer structured ferroelectrics (BLSFs) have drawn much attention due to their great potential for high‐temperature applications. It is generally accepted that BLSFs with small orthorhombic distortion should have low TC. In this paper, we report an anomalous example Li0.5Bi2.5Nb2O9 (LBN), which has small orthorhombic distortion but very high TC. LBN shows the highest TC (834°C) among currently reported prototype alkali‐metal BLSFs, which is attributed to its small tolerance factor. However, the refinement result reveals that LBN is orthorhombic with the space group of A21am, and the orthorhombic distortion of LBN a/b is merely 1.0019. The measurement of piezoelectric coefficient (d33 ∼ 6 pC/N) and observation of striped domain structure confirm the ferroelectricity nature of LBN. This work deepens our understanding of BLSFs and may lead to the finding of more novel BLSFs with high performance. [ABSTRACT FROM AUTHOR]

Bi0.5Na0.5TiO3‐based ceramics with high remnant polarization Pr have shown outstanding potential in the application of high‐power ferroelectric transducers. However, low depolarization temperature Td is an obstacle for their application. Here, a composition design strategy was proposed to simultaneously improve the Td and Pr in BNT‐based materials. Ultrahigh Pr of 40.56 µC/cm2 and relative high Td of 184°C were synergistically achieved in (Bi0.5Na0.5)(Ti0.995Mn0.005)O3 (BNMT) ceramics by adding 1.0 mol% BiGaO3 (BG), which is superior to other reported lead‐free systems. The excellent ferroelectric properties were attributed to strengthen ferroelectric order as evidenced by increased rhombohedral distortion. Meanwhile, the enhanced depolarization temperature, increasing from 168°C for x = 0% to 184°C for x = 1.0%, can be ascribed to the suppression of the thermal‐induced ferroelectric‐relaxor phase transition by adding BG. Those results enable the BNMT‐BG systems ceramics to be an attractive candidate for application in high‐power supplies. [ABSTRACT FROM AUTHOR]

(Pb, La)(Zr, Ti)O3 antiferroelectric (AFE) materials are promising materials due to their energy‐storage density higher than 10 J cm−3, but their low energy‐storage efficiency and poor temperature stability limit their application. In this paper, the (1 − x)(Pb0.9175La0.055)(Zr0.975Ti0.025)O3–xPb(Yb1/2Nb1/2)O3 (PLZTYN100x) AFE ceramics were prepared via two‐step sintering method and investigated thoroughly. With the doping of Yb3+ and Nb5+, the phase structure transforms from the orthorhombic phase (AFEO) to the coexistence of the orthorhombic‐and‐tetragonal phases. This structure reduces the free energy difference between the AFE and ferroelectric phases and reduces the fluctuation of energy with temperature, improving the energy storage efficiency and temperature stability. When the x = 0.05 (PLZTYN5), the AFE ceramic exhibits excellent temperature stability and ultrahigh energy storage performance, whose recoverable energy density (Wrec) is 6.8–8.2 J cm−3 at 30 kV mm−1 in the temperature range from −55 to 75°C, and efficiency (ƞ) is 78%–86.7%. In addition, the change of Wrec is less than 15%, exceeding the performance of most AFE ceramics. The results demonstrate that the PLZTYN5 ceramic has great potential in pulse power capacitors. [ABSTRACT FROM AUTHOR]

The recently discovered ductile/plastic inorganic semiconductors pave a new avenue toward flexible thermoelectrics. However, the power factors of current ductile/plastic inorganic semiconductors are usually low (below 5 µW cm−1 K−2) as compared with classic brittle inorganic thermoelectric materials, which greatly limit the electrical output power for flexible thermoelectrics. Here, large plasticity and high power factor in bulk two‐dimensional van der Waals (2D vdW) single‐crystalline SnSe2 are reported. SnSe2 crystals exhibit large plastic strains at room temperature and they can be morphed into various shapes without cracking, which is well captured by the inherent large deformability factor. As a semiconductor, the electrical transport properties of SnSe2 can be readily tuned in a wide range by doping a tiny amount of halogen elements. A high power factor of 10.8 µW cm−1 K−2 at 375 K along the in‐plane direction is achieved in plastic single‐crystalline Br‐doped SnSe2, which is the highest value among the reported flexible inorganic and organic thermoelectric materials. Combining the good plasticity, excellent power factors, as well as low‐cost and nontoxic elements, bulk 2D vdW single‐crystalline SnSe2 shows great promise to achieve high power density for flexible thermoelectrics. [ABSTRACT FROM AUTHOR]

This correction notice is for an article titled "High-entropy relaxor ferroelectric ceramics for ultrahigh energy storage" published in Nature Communications. The notice addresses two errors in the original article. The first error is in the first paragraph of page 4, where 'Tm,1MHz-Tm,10Hz' was incorrectly written. The correct version should state 'Tm,1MHz-Tm,10Hz'. The second error is in the first paragraph of page 7, where '(S1, S1)' was incorrectly written. The correct version should state '(Fig. S15)'. The correction has been made in both the PDF and HTML versions of the article. The authors of the article are Haonan Peng, Tiantian Wu, Zhen Liu, Zhengqian Fu, Dong Wang, Yanshuang Hao, Fangfang Xu, Genshui Wang, and Junhao Chu. [Extracted from the article]

Phase boundary provides a fertile ground for exploring emergent phenomena and understanding order parameters couplings in condensed-matter physics. In Pb(Zr1-xTix)O3, there are two types of composition-dependent phase boundary with both technological and scientific importance, i.e. morphotropic phase boundary (MPB) separating polar regimes into different symmetry and ferroelectric/antiferroelectric (FE/AFE) phase boundary dividing polar and antipolar dipole configurations. In contrast with extensive studies on MPB, FE/AFE phase boundary is far less explored. Here, we apply atomic-scale imaging and Rietveld refinement to directly demonstrate the intermediate phase at FE/AFE phase boundary exhibits a rare multipolar Pb-cations ordering, i.e. coexistence of antipolar or polar displacement, which manifests itself in both periodically gradient lattice spacing and anomalous initial hysteresis loop. In-situ electron/neutron diffraction reveals that the same parent intermediate phase can transform into either FE or AFE state depending on suppression of antipolar or polar displacement, coupling with the evolution of long-/short-range oxygen octahedra tilts. First-principle calculations further show that the transition between AFE and FE phase can occur in a low-energy pathway via the intermediate phase. These findings enrich the structural understanding of FE/AFE phase boundary in perovskite oxides. Ferroelectric/antiferroelectric phase boundary is both technologically and scientifically important. Here, the authors reveal the structure of intermediate phase involved in classical Pb(Zr1-xTix)O3. [ABSTRACT FROM AUTHOR]

The pressure‐driven force‐electric conversion materials with extremely rapid response time have been widely used in mining, defense, and energy areas. The discharge process by the force‐electric conversion effect in ferroelectrics is dominated by polar‐nonpolar phase transformation. In this work, (Pb0.985La0.01)(ZrxTi1‐x)O3 (PLZT, x = 0.85–0.94) ceramics is designed by tunning Zr4+/Ti4+ ratio and aliovalent La doping to achieve high remnant polarization (Pr) and excellent temperature stability. We focus on the pressure‐driven depolarization in PLZT ceramics, and their corresponding phase structure, ferroelectric properties, dielectric properties, and thermal depolarization. In PLZT (x = 0.93) ceramics, the original polarization P0 increases to 43.42 μC/cm2. The pressure‐driven depolarization releases 37.66 μC/cm2 with the depolarization proportion of 86.73%, which is attributed to irreversible ferroelectric‐antiferroelectric phase transition. It also exhibits excellent temperature stability up to 120°C (> 36 μC/cm2). This work provides a high‐performance alternative to Pb(Zr0.95Ti0.05)O3 and guidance for the development of pulse power energy conversion devices. [ABSTRACT FROM AUTHOR]

Pb0.99(Zr0.95Ti0.05)0.98Nb0.02O3 ferroelectric ceramics with porous structure of periodic distribution were fabricated successfully via Direct Ink Writing, a type of 3D printing technique. The effect of periodically distributed porous microstructure on the dielectric, ferroelectric, as well as hydrostatic‐pressure‐induced depolarization properties of PZT95/5 ferroelectric ceramics, was investigated. The printed porous ceramics exhibit relatively good viscoelasticity to retain the periodic structure during 3D printing and drying. In contrast with dense PZT95/5 ferroelectric ceramics prepared by conventional solid‐state sintering, low bulk density of the periodically distributed porous PZT95/5 ceramics leads to a decreased remanent polarization of 22.9 µC/cm2 under 2 kV/mm. As the hydrostatic pressure increased, the poled periodically distributed porous PZT95/5 ceramics depolarize sharply under a low and narrow hydrostatic pressure range of 113–116 MPa with a released charge density of 23.9 µC/cm2, while the poled dense PZT95/5 ceramics depolarize under a range of 250–278 MPa. Therefore, the introduction of periodically distributed micropores into PZT95/5 ceramics decreases the ferroelectric‐to‐antiferroelectric phase transition hydrostatic pressure significantly and maintained relatively excellent other properties simultaneously, such as temperature stability and low dielectric loss. The almost sharp depolarization behavior under a significantly decreased hydrostatic pressure demonstrates that periodically distributed porous PZT95/5 ferroelectric ceramics fabricated controllably by 3D printing exhibit excellent performances and prospects in mechanical–electrical energy conversion applications. [ABSTRACT FROM AUTHOR]

(Pb,La)(Zr,Ti)O3 antiferroelectric (AFE) ceramics have attracted considerable interest due to their high‐energy storage density and numerous field‐induced phase transitions. However, the positional equilibrium of the A‐site and B‐site is typically maintained without considering that heterovalent doping of La3+ can induce defects within the material, leading to high‐temperature leakage conduction. In this work, we introduced the acceptor ion Na+ at the A‐site simultaneously and designed Pb0.9175–0.5xLa0.055NaxZr0.975Ti0.025O3 (x = 0.01, 0.03, 0.055, 0.07, 0.10) AFE ceramics. The dielectric properties of these ceramics exhibited a consistent pattern of improvement followed by deterioration as the content of Na+ increased. Notably, when x = 0.055 (Na5.5), the AFE ceramic demonstrated superior high‐temperature frequency stability with negligible leakage conduction. Impedance spectroscopy analysis suggested that Na5.5 displays the greatest resistance and highest Edc. Concurrently, the thermally stimulated depolarization current indicates that Na5.5 possesses the lowest defect concentration and the largest Ea. This can be attributed to the internal generation of defect dipole clusters (VPb′′−VO••−NaPb′−LaPb•$V_{{\mathrm{Pb}}}^{{\prime\prime}} - V_{\mathrm{O}}^{ \bullet \bullet } - {\mathrm{Na}}_{{\mathrm{Pb}}}^{\prime} - {\mathrm{La}}_{{\mathrm{Pb}}}^ \bullet $), which effectively restrict the movement of charged defects. These findings suggest that Na5.5 holds significant potential for application and offer insights into the understanding of internal defects in lead‐based AFE materials. [ABSTRACT FROM AUTHOR]

PbZrO 3 has been broadly considered as a prototypical antiferroelectric material for high-power energy storage. A recent theoretical study suggests that the ground state of PbZrO 3 is threefold-modulated ferrielectric, which challenges the generally accepted antiferroelectric configuration. However, such a novel ferrielectric phase was predicted only to be accessible at low temperatures. Here, we successfully achieve the room-temperature construction of the strongly competing ferrielectric and antiferroelectric state by strain-mediated phase separation in PbZrO 3 /SrTiO 3 thin film. We demonstrate that the phase separation occurs spontaneously in quasi-periodic stripe-like patterns under a compressive misfit strain and can be tailored by varying the film thickness. The ferrielectric phase strikingly exhibitsa threefold modulation period with a nearly up-up-down configuration, which could be stabilized and manipulated by the formation and evolution of interfacial defects under applied strain. The present results construct a fertile ground for further exploring the physical properties and applications based on the novel ferrielectric phase., (© 2024. The Author(s).)