Excellent energy-storage properties of NaNbO3-based lead-free antiferroelectric orthorhombic P-phase (Pbma) ceramics with repeatable double polarization-field loops

The energy-storage performance of stable NaNbO₃-based antiferroelectric (AFE) ceramics was for the first time reported in (0.94-x)NaNbO₃-0.06BaZrO₃-xCaZrO₃ lead-free ceramics. A gradual evolution from an instable AFE phase (x≤0.01) to an orthorhombic AFE P phase (Pbma) (0.01<x≤0.05) was found to accompany the appearance of repeatable double-like polarization versus electric field loops although poled samples (x<0.01) own an AFE monoclinic phase (P2₁). Interestingly, compared with x≤0.01 samples with instable antiferroelectricity, a relatively high recoverable energy storage density W_rec ? 1.59 J/cm³ (@ 0.1 Hz) and a storage efficiency η of ?30% were achieved in the x = 0.04 ceramic. Moreover, a high W_rec of > 1.16 J/cm³ and an outstanding charge-discharge performance with fast discharge rate (t_0.9 < 100 ns) were generated in the temperature range from room temperature to 180 °C in the x = 0.04 ceramic. These results suggest that NaNbO₃-based AFE P-phase ceramics could be new potential dielectric materials for high-energy storage capacitors.     

The effect of A-site nonstoichiometry on the microstructure,electric properties,and phase stability of NaNbO3 polycrystalline ceramics

The impact of A-site nonstoichiometry on the microstructure, electric properties, and phase stability of sodium niobate ceramics (Na_1+xNbO₃, x = ?2 to 1 mol %) was investigated. All the components maintained an orthorhombic antiferroelectric (AFE) structure. The grain size increased from 3.9 to 14.3 μm with the variation in x from ?2 to 1. The AFE–FE phase transition electric field dramatically increased from 100 kV cm^?1 at x = 0 to 170 kV cm^?1 at x = ?2, confirming the enlarged energy barrier between AFE Pbma and FE Pmc2₁ phase under external field in A-site deficient components. This is attributed to the lattice compressive stress generated by introducing proper A-site vacancies. Combined results of transmission electron microscopy and Raman spectroscopy indicated that the AFE distortion of Pbma phase was significantly enhanced in A-site deficient components, which jointly contributed to the stability of AFE phase in A-site deficient NaNbO₃ material.     

Significantly enhanced energy storage performance in Sm-doped 0.88NaNbO3-0.12Sr0·7Bi0·2TiO3 lead-free ceramics

Lead-free antiferroelectric (AFE) ceramic materials have attached increasing attention in application of high-power capacitors for the past few years, due to their high energy storage density and environmental protection. However, the related applications are seriously restricted because of the limited number of environment friendly AFE candidate materials, high cost and low energy storage efficiency. In this work, the A-site ion Sm³⁺ doped 0.88NaNbO₃-0.12Sr_0·7Bi_0·2TiO₃ lead-free AFE P phase ceramics (0.88Na_1-3xSm_xNbO₃-0.12Sr_0·7Bi_0·2TiO₃, abbreviated as NN-SBT-100xSm) were prepared and characterized. With the increase of Sm doping amount, a relaxor-like behavior was found in the dielectric-temperature curves of NN-SBT-100xSm, indicating the AFE orthorhombic P phase is gradually replaced by an AFE orthorhombic R phase. As a result, double-like and slim P-E curve with near-zero residual polarization and suppressed hysteresis loss was obtained at x > 0.01. More encouragingly, a good discharge energy storage density (W_rec = 3.58 J/cm³) and a high efficiency (η = 82%) at a low electric field (E = 200 kV/cm) has been recorded simultaneously for NN-SBT-2Sm relaxor AFE ceramic, which are better than the other lead-free energy storage ceramics under the same E. In addition, the energy storage properties of NN-SBT-2Sm ceramics exhibit outstanding temperature and frequency stability. These results indicate that NN-SBT-2Sm relaxor AFE ceramic has a great practical value in pulse power capacitors.     

Metastable Ferroelectric Phase Induced by Electric Field in xPb(Zn1/3Nb2/3)O3–(1–x)Pb(Zr0.95Ti0.05)O3 Ceramics

A xPb(Zn_1/3Nb_2/3)O₃–(1–x)Pb(Zr_0.95Ti_0.05)O₃ (xPZN–(1–x) PZT) system close to antiferroelectric–ferroelectric (AFE–FE) morphotropic phase boundary has been prepared and investigated. The XRD results reveal PZN addition induces a phase transition from the orthorhombic (AFE) to rhombohedral (FE) phase through a phase coexistence region (AFE+FE). The polarization–electric field (P–E) measurements indicate that the AFE phase can be induced into a metastable FE (FE_m) phase. And the FE_m can recover to AFE around a critical temperature indicated by temperature‐dependent P–E loops. A composition‐temperature phase diagram was generalized within a certain range of PZN content in which an AFE–FE phase boundary connecting orthorhombic antiferroelectric to rhombohedral ferroelectric phase zones is formed near room temperature.     

Phase transition behavior of Pb(Hf,Sn, Ti,Nb)O3 ceramics at morphotropic phase boundary

The phase transition and dielectric properties of Pb_0.988(Hf_0.945Sn_xTi_0.03-xNb_0.025)O₃ ceramics (0 ≤ x ≤ 0.03, correspondingly abbreviated as H1, H2, H3, and H4) at the morphotropic phase boundary were systematically investigated. X-ray diffraction results and P-E hysteresis loops show that the dominate orthorhombic antiferroelectric phase and a small amount of the tetragonal FE phase coexist in Pb_0.988(Hf_0.945Sn_xTi_0.03-xNb_0.025)O₃ ceramics. As the Sn content increases, the antiferroelectricity is significantly enhanced, accompanied with an increased Curie temperature and sharply reduced peak dielectric constant. H1 and H2 experience an irreversible field-induced AFE-FE phase transition at the ambient temperature, and the transition from a metastable FE phase to the original AFE phase is observed in H2 when heated to 60°C. H3 and H4 experience an invertible AFE-FE phase transition, along with an enhanced forward phase switching field E_F. Moreover a decreased backward phase switching field E_A for H4 is detected as the electric field increases due to the AFE/FE coexistence. These results reveal the unique phase transition characteristics of AFE materials near the phase boundary, which is helpful for better understanding of AFE/FE materials.     

Achieving excellent energy storage density of Pb0.97La0.02(ZrxSn0.05Ti0.95-x)O3 ceramics by the B-site modification

The applications of antiferroelectric (AFE) materials in miniaturized and integrated electronic devices are limited by their low energy density. To address the above issue, the antiferroelectricity of the reinforced material was designed to improve its AFE-ferroelectric (FE) phase transition under electric fields. In this present study, the composition of Zr⁴⁺ (0.72 Å) and Ti⁴⁺ (0.605 Å) at B-site of Pb_0.97La_0.02(Zr_xSn_0.05Ti_0.95-x)O₃ ceramics with orthogonal reflections are synthesized via the tape-casting method. These ceramics are modified to enhance their antiferroelectricity by reducing their tolerance factor. A recoverable energy storage density W_rec 12.1 J/cm³ was obtained for x = 0.93 under 376 kV/cm, which is superior value than reported until now in lead-based energy storage systems. Moreover, the discharge energy density can reach 10.23 J/cm³, and 90 % of which can be released within 5.66 μs. This work provides a new window and potential materials for further industrialization of pulse power capacitors.     

Structure evolution and electric-field-induced reversible transition in perovskite Na(Nb1−xTax)O3 ceramics

Na(Nb_1−xTa_x)O₃ binary solid-solution ceramics with high quality were fabricated by conventional solid-state sintering routes for improving the electric(E)-field-induced irreversible polarization and transition behaviors of NaNbO₃. The studied results confirm that this binary solid-solution ceramics exhibit orthorhombic Pbcm space group companying with reduced unit-cell volume at x ≤ 0.4, and orthorhombic Pbnm space group at x = 0.5. As the Ta⁵⁺ content increases in the binary solid-solutions, the E-field-induced irreversible antiferroelectric → ferroelectric (AFE → FE) transition becomes reversible at x ≥ 0.2, giving rise to double-polarization hysteresis; the key E-fields triggering both irreversible and reversible transitions (E_F) increase in general. In particular, the E-field-induced FE phase at x = 0.15 is unstable upon unloading E-field to zero, which can return to AFE phase with time lapse. At x = 0.5, the Curie temperature (T_C) of AFE shifts to below room temperature, but E-field-induced reversible transition is still observed, which results in a nonlinear polarization with the lowest hysteresis and contributes to the largest energy-storage density. This transition is not due to the AFE ↔ FE transition but rather to the order ↔ disorder behavior of polar clusters or/and nanoregions within nonpolar Pbnm structure matrix.     

Significantly improved energy storage properties and cycling stability in La-doped PbZrO3 antiferroelectric thin films by chemical pressure tailoring

In this work, Pb_1−3x/2La_xZrO₃ (x = 0–0.12) (PLZ-x) antiferroelectric thin films were fabricated on Pt(111)/TiO₂/SiO₂/Si substrates using chemical solution method. Smaller cations (La³⁺) and vacancies were introduced into A-sites of perovskite structure to construct chemical pressure. According to phenomenological theory, chemical pressure can increase the energy barrier between antiferroelectric (AFE) and ferroelectric (FE) phase, and enhance antiferroelectricity of the system. As a result, a large energy storage density (W_re) of 23.1 J cm⁻³ and high efficiency (η) of 73% were obtained in PLZ-0.10 films, while PLZ-0 films displayed lower W_re (15.1 J cm⁻³) and η (56%). More importantly, PLZ-0.10 films exhibited an excellent cycling stability with a variation of ˜2% after 1 × 10⁸ cycles. The results demonstrate that heavily La-doped PbZrO₃ films with high energy storage density, high efficiency and excellent cycling stability can be considered as potential candidates for energy storage applications.     

Softening of antiferroelectric order in a novel PbZrO3-based solid solution for energy storage

PbZrO₃-based antiferroelectric (AFE) materials have received growing attention for their attractive energy storage performance. However, a major drawback of PZ is its high critical electric field (E_cr) which makes it difficult to switch the antiparallel dipoles therein so as to be useful. Therefore, softening of AFE order in PbZrO₃ is thought to be a promising approach for its practical applications. In this work, a new binary AFE solid solution of (1-x)PbZrO₃-xPb(Mg_1/2Mo_1/2)O₃ (PZ-PMM), with x = 0.00–0.10, was successfully synthesized in form of ceramics via the solid-state reaction method. The effect of chemical modification by introducing Pb(Mg_1/2Mo_1/2)O₃ on the crystal structure, phase transition behavior and electrical properties of the PbZrO₃ ceramics are investigated systemically. It is found that a perovskite phase with orthorhombic Pbam symmetry is preserved at room temperature for all the compositions studied, and a broadened ferroelectric intermediate phase exists between the paraelectric (PE) and the antiferroelectric phases of the PZ-PMM solid solution. At 160 °C, typical double hysteresis loop can be displayed for all the compositions. Most importantly, the maximum electric field-induced polarization is significantly increased, whereas the critical field is decreased with increasing PMM content, suggesting a remarkable softening effect of the antiferroelectric order in PZ due to some degree of dipole frustration. This work could bring about the development of a new series of PZ-based solid solutions for energy storage applications in the future.     

High energy storage properties of lead-free Mn-doped (1-x)AgNbO3-xBi0.5Na0.5TiO3 antiferroelectric ceramics

In this work, 0.2 wt.% Mn-doped (1-x)AgNbO₃-xBi_0.5Na_0.5TiO₃ (x = 0.00–0.04) ceramics were synthesized via solid state reaction method in flowing oxygen. The evolution of microstructure, phase transition and energy storage properties were investigated to evaluate the potential as high energy storage capacitors. Relaxor ferroelectric Bi_0.5Na_0.5TiO₃ was introduced to stabilize the antiferroelectric state through modulating the M₁-M₂ phase transition. Enhanced energy storage performance was achieved for the 3 mol% Bi_0.5Na_0.5TiO₃ doped AgNbO₃ ceramic with high recoverable energy density of 3.4 J/cm³ and energy efficiency of 62% under an applied field of 220 kV/cm. The improved energy storage performance can be attributed to the stabilized antiferroelectricity and decreased electrical hysteresis ΔE. In addition, the ceramics also displayed excellent thermal stability with low energy density variation (<6%) over a wide temperature range of 20−80 °C. These results indicate that Mn-doped (1-x)AgNbO₃-xBi_0.5Na_0.5TiO₃ ceramics are highly efficient lead-free antiferroelectric materials for potential application in high energy storage capacitors.     

Superior energy-storage properties in (Pb,La)(Zr,Sn,Ti)O3 antiferroelectric ceramics with appropriate La content

Antiferroelectric (AFE) ceramics based on Pb(Zr,Sn,Ti)O₃ (PZST) have shown great potential for applications in pulsed power capacitors because of their fast charge-discharge rates (on the order of nanoseconds). However, to date, it has been proven very difficult to simultaneously obtain large recoverable energy densities W_re and high energy efficiencies η in one type of ceramic, which limits the range of applications of these materials. Addressing this problem requires the development of ceramic materials that simultaneously offer a large ferroelectric-antiferroelectric (FE-AFE) phase-switching electric field E_A, high electric breakdown strength E_b, and narrow polarization-electric field (P-E) hysteresis loops. In this work, via doping of La³⁺ into (Pb_1-1.5xLa_x)(Zr_0.5Sn_0.43Ti_0.07)O₃ AFE ceramics, large E_A and E_b due to respectively enhanced AFE phase stability and reduced electric conductivity, and slimmer hysteresis loops resulting from the appearance of the relaxor AFE state, are successfully obtained, and thus leading to great improvement of the W_re and η. The most superior energy storage properties are obtained in the 3?mol% La³⁺-doped (Pb_1-1.5xLa_x)(Zr_0.5Sn_0.43Ti_0.07)O₃ AFE ceramic, which simultaneously exhibits at room temperature a large W_re of 4.2?J/cm³ and a high η of 78%, being respectively 2.9 and 1.56 times those of (Pb_1-1.5xLa_x)(Zr_0.5Sn_0.43Ti_0.07)O₃ AFE ceramics with x?=?0 (W_re?=?1.45?J/cm³, η?=?50%) and also being superior to many previously published results. Besides, both W_re and η change very little in the temperature range of 25–125?°C. The large W_re, high η, and their good temperature stability make the Pb_0.955La_0.03(Zr_0.5Sn_0.43Ti_0.07)O₃ AFE ceramic attractive for preparing high pulsed power capacitors useable in various conditions.     

Modulation of ferroelectricity and antiferroelectricity of nanoscale ZrO2 thin films using ultrathin interfacial layers

In this study, tailoring the microstructures and ferroelectric(FE)/antiferroelectric(AFE) properties of nanoscale ZrO₂ thin films is demonstrated with an intentional introduction of sub-nanometre interfacial layers. The ferroelectricity of ZrO₂ thin films is significantly enhanced by the HfO₂ interfacial layers, while the TiO₂ interfacial layers lead to a dramatic transformation of ZrO₂ from ferroelectricity into antiferroelectricity. The HfO₂ and TiO₂ interfacial layers boost the formation of the polar orthorhombic phase with (111)-texture and the non-polar tetragonal phase with (110)-texture in the FE/AFE ZrO₂ thin films, respectively, as evidenced by grazing incidence, out-of-plane, and in-plane X-ray diffraction measurements. Furthermore, the modulation of ferroelectricity and antiferroelectricity of nanoscale ZrO₂ thin films by the HfO₂/TiO₂ interfacial layers can be achieved without high-temperature annealing, which is highly advantageous to process integration. The findings demonstrate the important role of the interfaces in the effective tuning of FE/AFE properties of nanoscale thin films.     

Realizing room temperature double hysteresis loops in antiferroelectric NaNbO3 based ceramics

Lead-free antiferroelectric (AFE) materials have seen a surge of research activity in environmentally friendly energy storage technologies. Recently, considerable work has been done to improve the stability of AFE in NaNbO₃ (NN) ceramics, but it remains a grand challenge to obtain typical AFE characteristic double P-E loops in NN ceramics at ambient conditions. In a preliminary estimate of tolerance factor versus average electronegativity difference, we reported the stable AFE phase in 0.95NaNbO₃-0.05BiMg_2/3Ta_1/3O₃ sample. The orthorhombic Q to P phase transition was verified by XRD and TEM. Then, the remarkable double P-E loops were obtained in 0.95NaNbO₃-0.05BiMg_2/3Ta_1/3O₃ ceramics. Furthermore, a phenomenological model was proposed to explain the P-E relationships and our results. Compared with other reported compounds, the T_P-R decreased more obviously from 350 °C to 200 °C. Superior temperature stability (variations of maximum current, current density, and power density within 15% over 30–140 °C) and field induced phase transition were also confirmed by the pulse charge testing. Our work develops a new road for achieving room-temperature double P-E loops in NN ceramics by BiM₁M₂O₃ (M₁ might be Mg, Zn, etc; M₂ might be Nb, Ta, etc) additives.     

Evolving energy-storage performances during temperature-induced antiferroelectric P–R phase transition in NaNbO3-based lead-free ceramics

Temperature-driven antiferroelectric (AFE) P to AFE R phase transition in MnO₂-doped 0.90NaNbO₃-0.10CaTiO₃ ceramics was investigated through polarization-field response, energy-storage and charge-discharge properties as well as ex/in-situ multiscale structure characterization. Both room-temperature AFE P and high-temperature AFE R phases show double polarization-electric field hysteresis loops, indicating a reversible field-driven AFE to ferroelectric (FE) phase transition. An abnormal variation of critical fields for the AFE-FE and FE-AFE phase transition and a faster polarization-field response contribute to the reduced polarization hysteresis for both AFE P and R phases but an obviously expanded linear polarization-field response only for AFE R phase, being responsible for a two-time significant enhancement in energy-storage properties from P phase to P–R phase boundary and then to R phase. The variation of unit cell anisotropy and domain morphology with temperature was found to play crucial roles in the modulated field-driven phase transition behavior and polarization-field response on heating.     

High‐Performance Small‐Amount Fe2O3‐Doped (K,Na)NbO3‐Based Lead‐Free Piezoceramics with Irregular Phase Evolution

[(K_0.43Na_0.57)_0.94Li_0.06][(Nb_0.94Sb_0.06)_0.95Ta_0.05]O₃ + x mol% Fe₂O₃ (KNLNST + x Fe, x = 0~0.60) lead‐free piezoelectric ceramics were prepared by conventional solid‐state reaction processing. The effects of small‐amount Fe₂O₃ doping on the microstructure and electrical properties of the KNLNST ceramics were systematically investigated. With increasing Fe³⁺ content, the orthorhombic‐tetragonal polymorphic phase transition temperature (T_O‐T) of KNLNST + x Fe ceramics presented an obvious “V” type variation trend, and T_O‐T was successfully shifted to near room temperature without changing T_C (T_C = 315°C) via doping Fe₂O₃ around 0.25 mol%. Electrical properties were significantly enhanced due to the coexistence of both orthorhombic and tetragonal ferroelectric phases at room temperature. The ceramics doped with 0.20 mol% Fe₂O₃ possessed optimal piezoelectric and dielectric properties of d₃₃ = 306 pC/N, k_p = 47.0%, = 1483 and tan δ = 0.023. It was revealed that the strong internal stress in the KNLNST + x Fe ceramics with higher Fe³⁺ contents (x = 0.40, 0.60) stabilized the orthorhombic phase, leading to the irregular “V” type rather than the usually observed monotonic phase transition with composition change in the ceramics.     

Excellent energy-storage property and thermal stability of PLZT-based antiferroelectric ceramics

(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)(Pb_0.9175La_0.055)(Zr_0.975Ti_0.025)O₃–xPb(Yb_1/2Nb_1/2)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 (AFE_O) 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 (W_rec) 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 W_rec 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.     

Achieving high energy storage performance of Pb(Lu1/2Nb1/2)O3 antiferroelectric ceramics via equivalent A-site engineering

Manipulating the critical switching field between antiferroelectric (AFE) state and ferroelectric (FE) is an important concept for tuning the energy storage performance of AFEs. As one of the lead-based AFE systems, Pb(Lu_1/2Nb_1/2)O₃ promises high potential in the miniaturization of pulsed power capacitors, but the extremely high critical switching field and low induced saturated polarization demonstrate severe drawbacks with respect to temperature stability and flexibility. Here, A-site Ba²⁺ doping engineering is used to effectively reduce the critical switching field and improve the saturated polarization in Ba_xPb_1-x(Lu_1/2Nb_1/2)O₃ (0.01 ≤ x ≤ 0.08, abbreviated as xBa-PLN) ceramics. We found the AFE-FE phase transition can be occurred at 80ºC with a high energy storage density of 4.03 J/cm³ for Ba_0.06Pb_0.94(Lu_1/2Nb_1/2)O₃ ceramic. Our results show that Ba²⁺ additions destroy the antiparallel structure of AFE phase, and finally reduce the critical switching field, demonstrating a potential alternative to modulate the energy storage performance of AFEs.     

High piezoelectric properties of BaTiO3-xLiF ceramics sintered at low temperatures

BaTiO₃-xLiF ceramics were prepared by a conventional sintering method using BaTiO₃ powder about 100 nm in diameter. The effects of LiF content (x) and sintering temperature on density, crystalline structure and electrical properties were investigated. A phase transition from tetragonal to orthorhombic symmetry appeared as sintering temperatures were raised from 1100 °C to 1200 °C or as LiF was added from 0 mol% to 3 mol%. BaTiO₃-6 mol% LiF ceramic sintered at 1000 °C exhibited a high relative density of 95.5%, which was comparable to that for pure BaTiO₃ sintered at 1250 °C. BaTiO₃-4 mol% LiF ceramic sintered at 1100 °C exhibited excellent properties with a piezoelectric constant d₃₃ = 270 pC/N and a planar electromechanical coupling coefficient k_p = 45%, because it is close to the phase transition point in addition to high density.     

Room temperature phase superposition as origin of enhanced functional properties in BaTiO3 - based ceramics

BaSn_xTi_1-xO₃ (x = 0, 0.05) ceramics with orthorhombic/tetragonal phases at room temperature were comparatively investigated to understand the role of phase composition on their functional properties. With respect to the values of BaTiO₃, the switching polarization, permittivity peak, tunability and piezoelectric coefficients are enhanced by doping with 5 % Sn onto Ti⁴⁺ sites. The orthorhombic polymorph amount is larger in the doped ceramic and explains its higher switching polarization. High field poling favors the orthorhombic phase in both compositions; this polymorph becomes predominant in the BaSn_0.05Ti_0.95O₃ ceramic. Landau-based calculations developed for ceramics with randomly oriented grains predicted the stability of variable amounts of orthorhombic/tetragonal phases around room temperature and explain the field-induced predominant orthorhombic state, mostly in BaSn_0.05Ti_0.95O₃. Due to the twelve allowed spontaneous polarization directions, the orthorhombic state is responsible for the enhanced polarization, tunability and piezoelectric properties with respect to the tetragonal state with six polarization possible orientations.     

Structure and energy storage performance of Ba-modified AgNbO3 lead-free antiferroelectric ceramics

The AgNbO₃ antiferroelectric (AFE) ceramics have attracted increasing attention for their high energy storage performance and environmentally friendly characters. In this work, Ag_1–2xBa_xNbO₃ ceramics were successfully prepared by the conventional solid-state reaction method. The effect of Ba-modification on phase structure, microstructure, and electric properties was systematically investigated. The introduction of Ba²⁺ ion led to complex cell parameter evolution and significant refinement of grain size. Room temperature dielectric permittivity increased obviously from ~260 for the pure AgNbO₃ counterpart to ~350 for those after adding a small amount of Ba element. Slim P-E hysteresis loops with improved AFE phase were achieved after Ba modification, due to the decrease of tolerance factor. A high recoverable energy density up to 2.3?J/cm³ with energy efficiency of 46% can be obtained for the composition of Ag_0.96Ba_0.02NbO₃, in correlation with the enhanced AFE stability, reduced P_r, increased P_m and decreased ΔE. Moreover, the Ag_0.96Ba_0.02NbO₃ ceramics also exhibited excellent temperature stability in both energy density and efficiency with small variation of <?5% over 20–120?℃. The results suggest that the electric properties of AgNbO₃ system can be largely tuned after Ba modification, making it a promising candidate for energy storage applications.