Enhanced Energy Storage Properties Research Articles

Enhanced Energy Storage Properties of Polypropylene through Crystallization Modulation

Enhanced Energy Storage Properties of Polypropylene through Crystallization Modulation

Enhanced energy storage properties of silver niobate antiferroelectric ceramics with A-site Eu3+ substitution and their structural origin

AgNbO3 (AN)-based lead-free antiferroelectric ceramics are widely studied for their use as dielectric capacitor materials. In this study, Eu3+-doped AN ceramics were prepared and the results show that Eu3+ diffused into the AN lattice. The ceramics were formed by M1 and M2 phases coexisting at room temperature, as distinct from the M1 (M: monoclinic) phase of pure AN. Electrical properties and structural characterization showed that the antiferroelectric stability of the ceramics increases with the increase in Eu3+ levels. At room temperature, Ag0.94Eu0.02NbO3 ceramic exhibited a good energy storage density of 5.3 J/cm3 and a high efficiency of 71.9%. When the temperature rises from room temperature to 140 °C, the efficiency of the sample decreases from 80.4% to 67.1% and Wr decreases from 2.1 to 2.0 J/cm3, which indicates that the sample has good temperature stability. The time constant (t0.9) of this sample was less than 60 ns and the power density (PD) was 51.3 MW/cm3, indicating excellent charge–discharge capabilities. This novel ceramic is expected to be used as a new dielectric capacitor material for pulsed power supplies.

Enhanced energy storage properties of (Ba0.4Sr0.6)TiO3 ceramics with ultrahigh energy efficiency through doping of Bi0.2Sr0.7(Mg1/3Nb2/3)O3

Dielectric (Ba0.4Sr0.6)TiO3 (BST) ceramics are promising dielectric energy storage materials due to their moderate dielectric constant, low dielectric loss, and slight nonlinearity. However, their energy density is limited by their low breakdown strength (BDS). In this study, we aimed to address this limitation by incorporating various amounts of Bi0.2Sr0.7(Mg1/3Nb2/3)O3 (SBMN) into the BST matrix. The (1–x)BSTxSBMN ceramics were prepared by conventional solid-state sintering, resulting in single-phase solid solutions. Compared to pure BST ceramics, the (1–x)BST–xSBMN ceramics exhibited lower remnant polarization and significantly enhanced BDS. Furthermore, the relaxation of the ceramics enhanced with increasing doping concentration, with an efficiency of η = 94.0% achieved at x = 0.20. Among them, the breakdown field strength of 0.85BST–0.15SBMN ceramics was 597 kV cm−1, achieving a recoverable energy storage density of Wrec = 2.81 J cm−3 and an efficiency of η = 90.8% under an external electric field of 480 kV cm−1. Subsequent tests revealed that the introduction of SBMN not only increased the band gap and conduction activation energy of the material, leading to an increase in BDS, but also promoted the formation of polar nanoregions (PNRs) which contributed to boosted energy efficiency, resulting in a significant enhancement in the energy storage performance of BST ceramics.

Enhanced energy storage property of all-organic dielectrics by gradient layered design of sea-island structures

Enhanced energy storage property of all-organic dielectrics by gradient layered design of sea-island structures

Enhanced energy storage properties in BNST-based lead-free relaxor ferroelectric ceramics achieved via a high-entropy strategy

The 0.65(Bi0.5Na0.5)TiO3–0.35SrTiO3-based materials are essential for the development of pulse power capacitors. However, their low recoverable energy storage density and breakdown field strength have hindered further improvement. To address this, a high-entropy strategy based on multiscale regulation is proposed, which involves synergistically manipulating the activation energy and microstructure evolution in BNST-based ceramics through the introduction of Ba(Zr0.2Ti0.2Sn0.2Hf0.2Ta0.2)O3. The inclusion of high-insulating oxides can significantly raise the activation energy of the entire system. Furthermore, the high-entropy material can significantly increase the atomic disorder and lattice distortion, resulting in strong local polar fluctuations on several nanoscales and excellent energy storage characteristics. As a result, this approach yields an impressive Wrec of ∼ 4.89 J/cm3 and a high efficiency of ∼92.1 % at 351 kV/cm, and the outstanding thermal endurance (20∼150 °C), frequency stability (5∼1000 Hz) and fatigue (100∼105 cycles). This study provides an effective strategy for achieving excellent comprehensive performances in high-entropy ceramics.

The enhanced energy storage properties of (1-x)(0.94BNT-0.06BT)-x(Bi0.2Na0.2K0.2La0.2Sr0.2)TiO3 solid solutions

A strategy is developed to enhance the energy storage properties of lead-free Bi0.5Na0.5TiO3-based solid solutions, which is implemented through coupling the lattice instability in 0.94(Bi0.5Na0.5)TiO3-0.06BaTiO3 (0.94BNT-0.06BT) ferroelectric with a composition at its morphotropic phase boundary with the chemical disorder in (Bi0.2Na0.2K0.2La0.2Sr0.2)TiO3 (BNKLST) high-entropy ceramic (HEC). The addition of BNKLST in 0.94BNT-0.06BT could suppress the relaxor behaviors in the resulting solid solutions (1-x)(0.94BNT-0.06BT)-xBNKLST. With increasing content x, BNKLST may triggers more polar nano-regions which are in ergodic states at elevated temperatures. As a result, the thermal stability for energy storage properties is increased. In particular, the solid solution with x = 0.3 not only possesses large dielectric constants but also has a low content of oxygen vacancies, beneficial to its dielectric properties; It exhibits an excellent recoverable energy storage density of 2.24 J/cm3 under an electric field of 140 kV/cm, and a good thermal stability at 50 kV/cm with energy storage efficiency η >80 % up to 200 °C. The results demonstrate that the synergy effect of lattice instability and chemical disorder in the solid solutions is effective in enhancing energy storage properties of HECs, facilitating the design and optimization of dielectric energy storage devices.

Enhanced energy storage properties of Sm(Mg0.5Ti0.5)O3 modified (Bi0.5Na0.5)0.7Sr0.3TiO3 relaxor ferroelectric ceramics

Developing high performance and pollution-free energy storage devices is crucial for the development of the energy industry. The Sm(Mg0.5Ti0.5)O3-modified (Bi0.5Na0.5)0.7Sr0.3TiO3 ((1-x)BNST–xSMT, x = 0.00–0.15)) relaxor ceramics were synthesized by using a traditional solid-state sintering method. The phase structure, microstructure, dielectric spectrum, and energy storage properties were studied. The x = 0.10 sample obtained an energy storage density of 4.33 J/cm3 under an electric field of 290 kV/cm, while the energy storage efficiency reached 80 %. In addition, the variation of energy storage density remains within ±4 % and the energy storage efficiency is above 80 % at a frequency of 1–100 Hz and a temperature of 25–120 °C, respectively, indicating that the x = 0.10 sample has good stability in both temperature and frequency. The energy storage decreases slightly with increasing temperature and frequency, which originates from the migration of intrinsic charge carriers and the weakening of the interaction force between cations and anions. In addition, the x = 0.10 sample exhibits good fatigue resistance, with little change in the ferroelectric loop after 105 cycles. This performance advantage indicates that the (1-x)BNST-xSMT ceramic systems have great potential in the field of high energy storage.

Local structural mechanism for enhanced energy storage properties in heterovalent doped NaNbO3 ceramics

In recent years, there is a growing interest for new lead-free oxides with reversible antiferroelectric (AFE)-ferroelectric (FE) phase transition for high-power energy-storage applications. NaNbO3-based ceramics are particularly attractive due to their easy synthesis and cost-effectiveness. In order to stabilize reversible AFE-FE phase transition, NaNbO3 is doped with a combination of heterovalent substitutions, although the underlying structural mechanism for the same is poorly understood. Here, we investigated local and average structures of Ca/Zr doped NaNbO3 using neutron total scattering. We show that Ca/Zr doping increases the average AFE phase (Pbma) fraction, however, the material remains as a composite of both FE (P21ma) and AFE regions. Analysis of local structure suggests that increase in the long-range AFE phase results from more extensive twinning of local FE regions, due to introduced charge disorder. We propose that enhanced energy-storage properties of Ca/Zr-doped NaNbO3 arises from localized twin boundary motion between the defect-induced pinning centers.

Enhanced energy storage properties and good stability of novel (1–x)Na0.5Bi0.5TiO3–xCa(Mg1/3Nb2/3)O3 relaxor ferroelectric ceramics prepared by chemical modification

The increase in energy consumption and its collateral damage on the environment has encouraged the development of environment-friendly ceramic materials with good energy storage properties. In this work, (1–x)Na0.5Bi0.5TiO3-xCa(Mg1/3Nb2/3)O3 ceramics were synthesized by the solid-state reaction method. The 0.88Na0.5Bi0.5TiO3-0.12Ca(Mg1/3Nb2/3)O3 ceramic exhibited a high recoverable energy storage density of 8.1 J/cm3 and energy storage efficiency of 82.4% at 550 kV/cm. The introduction of Ca(Mg1/3Nb2/3)O3 reduced the grain size and increased the band gap, thereby enhancing the breakdown field strength of the ceramic materials. The method also resulted in good temperature stability (20–140 °C), frequency stability (1–200 Hz), and fatigue stability over 106 cycles. In addition, an ultrahigh power density of 187 MW/cm3 and a fast charge-discharge rate (t0.9 = 57.2 ns) can be obtained simultaneously. Finite element method analysis revealed that the decrease of grain size was beneficial to the increase of breakdown field strength. Therefore, the 0.88Na0.5Bi0.5TiO3-0.12Ca(Mg1/3Nb2/3)O3 ceramics resulted in high energy storage properties with good stability and were promising environment-friendly materials for advanced pulsed power systems applications.

Enhanced energy storage properties of (Bi0.2Na0.2Ca0.2Ba0.2Sr0.2)(Ti1-xZrx)O3 high entropy ceramics by Zr doping at B-site

Due to their interesting properties derived from the high entropy effect, high entropy ceramics (HECs) with perovskite structure are considered promising candidates for energy storage applications. In this paper, lead-free (Bi0.2Na0.2Ca0.2Ba0.2Sr0.2)(Ti1-xZrx)O3 (BNCBST-xZr, 0.01 ≤ x ≤ 0.15) HECs were prepared by a hydrothermal technique. The results show that as-prepared samples present a single pseudo-cubic structure, and the Zr doping at the B site of BNCBST provokes lattice distortion and deepens dielectric relaxation. In addition, the grain size is reduced by the incorporation of Zr, leading to the improvement of electrical breakdown strength (Eb). Accordingly, BNCBST-0.05Zr ceramic exhibits optimal energy storage characteristics, as indicated by an excellent recoverable energy density (Wrec) of 3.03 J/cm3 and energy storage efficiency (η) of 84.7% under a great Eb of 307 kV/cm). A wide temperature stability (Wrec and η vary within ±9.3 % and ±1.7 % at 40–100 °C) and short discharge time (100 ns) are also observed in BNCBST-0.05Zr ceramic. These results demonstrates that Zr doping can effectively optimize the Eb as well as the energy storage properties of ceramics, and the prepared BNCBST-0.05Zr HEC is attractive dielectric materials in energy-storage devices.

Enhanced energy storage properties of all-polymer dielectrics by cross-linking

Polymer dielectrics with good energy storage properties are need for advanced electric devices. Herein, a new class of all organic dielectric cross-linkable polymers, poly(methyl methacrylate-glycidyl methacrylate) (P(MMA-GMA)) prepared by radical polymerization, is reported. A comprehensive investigation was conducted to examine the impact of the cross-linked monomer GMA content on the energy storage properties. The crosslinking significantly enhances the breakdown strength and suppresses the leakage currents. Consequently, the copolymer P(MMA-GMA) containing 7 mol% GMA exhibits a high discharge energy density of 16.5 J/cm3 at 750 MV/m, coupled with a high discharge efficiency of 82%. Even at an elevated temperature of 100 °C, it still possesses a good energy performance of a discharge energy density of 12.1 J/cm3 and a relatively high efficiency of 80.1% at 650 MV/m. This study offers a simple and effective approach to fabricating all-organic polymer dielectrics with good energy storage properties.

Enhanced energy storage properties of Bi0.5Na0.5TiO3-based ceramics via regulating the doping content and sintering temperature

Eco-friendly lead-free energy-storage ceramics featuring high energy storage properties and ultra-high stability have been regarded to be one of the most potential materials in the field of energy storage. In this work, a new element system, (1-x)(0.6Bi0.5Na0.5TiO3-0.4SrTiO3)-xBi[Zn2/3(Nb0.5Ta0.5)1/3]O3 ((1-x)BNST-xBZNT) lead-free ceramics, were synthesized via a conventional solid-state sintering technology. And the phase structure, microstructure and energy storage properties of the (1-x)BNST-xBZNT ceramics were comprehensively studied. After the introduction of BZNT, the average grain size of the materials is greatly decreased, thereby enhancing the dielectric breakdown strength (DBS). Additionally, the thermal stability of the ceramics is significantly improved via regulating the doping content and sintering temperature. Furthermore, the ferroelectric long-range order of the ceramics is decomposed into randomly-oriented polar nano-domains (PNRs) after introducing BZNT, leading to strong relaxor behavior and significantly reducing remanent polarization (Pr). As a result, even under a relatively low electric field of 139 kV/cm, the 0.98BNST-0.02BZNT ceramic sintered at 1150 °C possesses high values of energy storage efficiency (η) value of 92.78% and total energy storage density (Wtot) of 1.67 J/cm3 as well as remarkable thermal stability (25–175 °C), frequency stability (20–70 Hz) and fatigue resistant stability (100-105 cycles). This investigation provides a useful reference for developing advanced energy storage ceramics by regulating the doping content and sintering temperature.

Simultaneously realizing ultrahigh energy storage density and efficiency in BaTiO3-based dielectric ceramics by creating highly dynamic polar nanoregions and intrinsic conduction

Nowadays, it is urgent to explore advanced and eco-friendly energy storage capacitors based on lead-free relaxor ferroelectric (RFE) ceramics in order to meet the ever-increasing requirements in pulsed power systems. BaTiO3 (BT)-based RFE ceramics are considered as ones of the best high-temperature energy storage materials due to their good thermal stability. However, relatively low recoverable energy storage density (Wrec<5 J/cm3) has been a key bottleneck restricting the practical applications of them. Here, a novel strategy is proposed to create highly dynamic PNRs and the intrinsic conduction by introducing Bi(M1-0.015xTa0.015x)O3+0.015x (BMO-Ta, M=Mg2/3Ta1/3) to BT matrix. As a consequence, the designed (1-x)BT-x(BMO-Ta) ceramics exhibit dramatically enhanced energy storage properties including ultrahigh Wrec and efficiency (η), because of the coexistence of very slim polarization hysteresis (P-E) loops, large polarization difference (ΔP) and giant dielectric breakdown electric strength (Eb). Wrec and η of the x=0.25 ceramic reach up to 9.03 J/cm3 and 95.2% under 720 kV/cm, respectively. Furthermore, it shows excellent temperature/frequency/cycling stability over a wide range of 20−200 °C, 1−500 Hz and 1−3.3 × 105 cycles, respectively (the variations of Wrec and η are < 3% and < 4%, respectively). The findings in this paper not only indicate excellent comprehensive properties achieved in the novel (1-x)BT-x(BMO-Ta) system, but also provide an effective approach to explore advanced energy storage capacitors in other lead-free ceramic systems.

Enhanced energy storage properties in Nb-doped (Na0.5Bi0.5)TiO3-SrTiO3 lead-free relaxor ferroelectric ceramics

In this article, optimized energy-storage density obtained at low electric field and accompanied with high efficiencies was achieved simultaneously by donor-doping Nb5+ into 0.65(Na1/2Bi1/2)TiO3–0.35SrTiO3 system. The donor addition of Nb5+ may force Ti4+ to become Ti3+ due to the imbalance of ion valence after the Nb5+ substitution of Ti4+, leading to the formation of Ti3+-Nb5+ ion pair. The self-built electric field generated by Ti3+-Nb5+ ion pair is conducive to obtain slim P-E loops with high P max and negligible P r. Accordingly, a high recoverable energy densities of 1.04 J/cm3 with a high energy efficiencies of 86.7% was achieved under 82 kV/cm at x = 0.25 mol.% due to the enhanced E b and P max-Pr values. This work provides a promising approach for designing high-performance lead-free energy storage ceramics under low electric fields.

Enhanced energy storage properties in PbZrO3 thin films via the incorporation of NiO

In this study, NiO–PbZrO3 composite films were deposited on SiO2/Si substrates buffered with LaNiO3 films via the sol-gel coating technique. The effects of NiO addition in PZO thin films on the microstructure, dielectric properties, leakage mechanism, ferroelectric properties and energy storage properties have been discussed. The dielectric constant increased with the addition of NiO, while the leakage current density decreased. Compared with pure PZO films, the maximum polarization of the composite films was improved. For the composite films prepared using the NiO precursor solution with 0.05 mol/L, the recoverable energy storage density of the NiO-PZO composite film is up to 19.6 J/cm3 under the electric field of 1038 kV/cm, which is 30% higher than that of the pure PZO film under the same conditions. Also, the energy storage efficiency of the composite film reaches 48%. Accordingly, we demonstrate a simple and convenient method by adding NiO to fabricate thin films with high energy storage performance.

Inner Mechanism of Enhanced Energy Storage Properties and Efficiency for CaTiO3 Modified 0.92NaNbO3-0.08Bi(Mg0.5Ti0.5)O3 Lead-Free Ceramics

Inner Mechanism of Enhanced Energy Storage Properties and Efficiency for CaTiO3 Modified 0.92NaNbO3-0.08Bi(Mg0.5Ti0.5)O3 Lead-Free Ceramics

Enhanced Energy Storage Properties in Paraelectrics via Entropy Engineering

AbstractElectrostatic energy storage capacitors based on dielectrics have attracted much attention due to their wide applications in advanced electrical technology and electronic devices. Generally, high energy density is achieved at a high electric field, while conduction loss becomes nonnegligible, which harms practical applications. Here distinctly suppressed leakage current in BaZr0.5Ti0.5O3‐based films by entropy engineering is realized. With increased entropy, the leakage current density decreases by two orders of magnitude at the electric field of 3 MV cm−1, leading to a markedly improved energy efficiency of 87% at an ultrahigh breakdown strength of 8 MV cm−1 in high‐entropy films. Thereby, a high energy density of 51.9 J cm−3 is achieved. This work demonstrates the effectiveness of entropy engineering in improving the breakdown strength of dielectric films and shows great potential in enhancing the energy storage performance of capacitors.

Synergistic enhanced energy storage performance of NBT-KBT ceramics by K0.5Na0.5NbO3 composition design

(1–x)(0.8Na0.5Bi0.5TiO3-0.2K0.5Bi0.5TiO3)-xK0.5Na0.5NbO3 (x = 0, 0.1, 0.2, 0.3, 0.4) (NBT-KBT-KNN) ceramic solid solution was synthesized by solid phase method through designing KNN composition. XRD, Raman and SEM results show that NBT-KBT-KNN ceramics form solid solutions with a stable perovskite structure. The dielectric temperature spectrum and impedance spectrum analysis confirmed that the relaxor ferroelectrics (RFE) properties enhanced with increasing KNN content. The piezoresponse force microscopy (PFM) results reveal that the introduced KNN disrupts the microdomains of NBT-KBT ceramics and promotes the formation of nanodomains, leading to enhanced energy storage properties. The breakdown electric field strength (BDS) was also increased with increasing KNN content, and maximum value was obtained at x = 0.2. The addition of KNN can obviously improve energy storage performance (ESP). At 255 kV cm–1, x = 0.2 produced excellent ESP with recoverable energy storage density (Wrec), amazingly normalized response (ξ), efficiency (η) and maximum polarization (Pmax) are 3.38 J cm–3, 132.55 J kV–1 m–2, 85.4 %, and 45.76 μC cm–2, respectively. ESP is also stable in terms of frequency and temperature at (1–100 Hz) and (20–140 °C). At 120 kV cm–1, the discharge energy density (Wdis), power density (PD), Current density (CD) and time for releasing 90 % of total energy density (t0.9), are 0.202 J cm–3, 23.43 MW cm–3, 390.42 A cm–2, and 56.6 ns. These findings demonstrate that NBT-KBT-KNN ceramics have the ability to be reliable energy storage and pulse power capacitors.

Enhanced energy storage properties of 0.93NaNbO3–0.07Bi(Mg0.5Zr0.5)O3 ceramics by doping linear perovskite material

Enhanced energy storage properties of 0.93NaNbO3–0.07Bi(Mg0.5Zr0.5)O3 ceramics by doping linear perovskite material

Synthesis of functionalized ZnO nanoflake loaded polyvinylidene fluoride composites with enhanced energy storage properties

AbstractPolymer composite films are ideal materials for advanced energy storage capacitor in electrical systems. Therefore herein, we fabricated a novel series of polyvinylidene fluoride (PVDF) based composites embedded with well dispersed ZnO@APTES {surface modified zinc oxide with (3‐Aminopropyl) triethoxysilane (APTES)} nanoflake (0, 20, 30, 40, 50) vol% through solution casting method. Hydrothermally synthesized two‐dimensional ZnO was pre‐treated with H2O2 and surface modified with APTES for perfect distribution of nanoflake into PVDF matrix. Surface modification and high aspect ratio morphology of ZnO@APTES enhanced the interfacial interaction between organic PVDF and inorganic ZnO through reduction in heterogeneity between them. Surface functionalization reduced the dielectric loss and improved the overall energy storage performance. Investigation of electrical properties proclaimed incorporating 30 Vol% ZnO@APTES in PVDF as optimized loading due to its appreciable Wrec (recoverable energy density) about 3.2 J/cm3. Relative comparison of the energy storage density (Wrec) of PVDF/ZnO@APTES (30) vol% with recent published works established its enhanced capacitive response and its future application in energy storing portable device.