Moderate Fields, Maximum Potential: Achieving High Records with Temperature-Stable Energy Storage in Lead-Free BNT-Based Ceramics

Shi, Wen**g; Zhang, Leiyang; **g, Ruiyi; Huang, Yunyao; Chen, Fukang; Shur, Vladimir; Wei, **aoyong; Liu, Gang; Du, Hongliang; **, Li

doi:10.1007/s40820-023-01290-4

Moderate Fields, Maximum Potential: Achieving High Records with Temperature-Stable Energy Storage in Lead-Free BNT-Based Ceramics

Article
Open access
Published: 18 January 2024

Volume 16, article number 91, (2024)
Cite this article

Download PDF

You have full access to this open access article

Nano-Micro Letters Aims and scope Submit manuscript

Moderate Fields, Maximum Potential: Achieving High Records with Temperature-Stable Energy Storage in Lead-Free BNT-Based Ceramics

Download PDF

Wen**g Shi¹,
Leiyang Zhang¹,
Ruiyi **g¹,
Yunyao Huang¹,
Fukang Chen²,
Vladimir Shur³,
**aoyong Wei¹,
Gang Liu²,
Hongliang Du⁴ &
…
Li **¹

2206 Accesses
9 Citations
1 Altmetric
Explore all metrics

Highlights

Achieving ultrahigh energy-storage density (7.19 J cm⁻³) and outstanding storage efficiency (93.8%) at 460 kV cm⁻¹ in BNT-based relaxor ferroelectric ceramics under a moderate electric field.
Superior energy-storage performance accomplished through meticulous regulation of permittivity, enhancement of insulation quality, and strategic domain engineering via chemical formula optimization.
The intricate structure–property relationship elucidated with precision using high-resolution transmission electron microscopy.

Abstract

The increasing awareness of environmental concerns has prompted a surge in the exploration of lead-free, high-power ceramic capacitors. Ongoing efforts to develop lead-free dielectric ceramics with exceptional energy-storage performance (ESP) have predominantly relied on multi-component composite strategies, often accomplished under ultrahigh electric fields. However, this approach poses challenges in insulation and system downsizing due to the necessary working voltage under such conditions. Despite extensive study, bulk ceramics of (Bi_0.5Na_0.5)TiO₃ (BNT), a prominent lead-free dielectric ceramic family, have seldom achieved a recoverable energy-storage (ES) density (W_rec) exceeding 7 J cm⁻³. This study introduces a novel approach to attain ceramic capacitors with high ESP under moderate electric fields by regulating permittivity based on a linear dielectric model, enhancing insulation quality, and engineering domain structures through chemical formula optimization. The incorporation of SrTiO₃ (ST) into the BNT matrix is revealed to reduce the dielectric constant, while the addition of Bi(Mg_2/3Nb_1/3)O₃ (BMN) aids in maintaining polarization. Additionally, the study elucidates the methodology to achieve high ESP at moderate electric fields ranging from 300 to 500 kV cm⁻¹. In our optimized composition, 0.5(Bi_0.5Na_0.4K_0.1)TiO₃–0.5(2/3ST-1/3BMN) (B-0.5SB) ceramics, we achieved a W_rec of 7.19 J cm⁻³ with an efficiency of 93.8% at 460 kV cm⁻¹. Impressively, the B-0.5SB ceramics exhibit remarkable thermal stability between 30 and 140 °C under 365 kV cm⁻¹, maintaining a W_rec exceeding 5 J cm⁻³. This study not only establishes the B-0.5SB ceramics as promising candidates for ES materials but also demonstrates the feasibility of optimizing ESP by modifying the dielectric constant under specific electric field conditions. Simultaneously, it provides valuable insights for the future design of ceramic capacitors with high ESP under constraints of limited electric field.

High energy storage properties of Nd(Mg2/3Nb1/3)O3 modified Bi0.5Na0.5TiO3 lead-free ceramics

Article 20 February 2024

Broad-high operating temperature range and enhanced energy storage performances in lead-free ferroelectrics

Article Open access 15 September 2023

Bi0.5Na0.5TiO3-based ceramics with high energy storage density and good thermal stability

Article 21 November 2021

Use our pre-submission checklist

Avoid common mistakes on your manuscript.

1 Introduction

In contrast with supercapacitors, lithium–ion batteries, and fuel cells, dielectric ceramic capacitors have emerged as a focal point in pulse electrical devices owing to their remarkable power density, rapid charge–discharge response, and broad operating temperature range [1,2,3]. However, their current bottleneck resides in a relatively lower energy-storage (ES) density, impeding widespread integration into pulse electrical devices [4,5,6]. Consequently, there is a pressing need to engineer dielectric materials with heightened energy-storage performance (ESP). The assessment of a dielectric material's ESP typically involves parameters such as W (total ES density), W_rec (recoverable ES density), W_loss (dissipated ES density), and η (ES efficiency). These parameters are determined through the measurement of polarization versus electric field (P–E) curves and are calculated using the following equations [7]:

$$W = \mathop \int \limits_{0}^{{P_{\max } }} E\,{\text{d}}P$$

(1)

$$W_{{{\text{rec}}}} = \mathop \int \limits_{{P_{r} }}^{{P_{{{\text{max}}}} }} E\,{\text{d}}P$$

(2)

$$\eta = \frac{{W_{{{\text{rec}}}} }}{W}100\% = \frac{{W_{{{\text{rec}}}} }}{{W_{{{\text{rec}}}} + W_{{{\text{loss}}}} }}100\%$$

(3)

Here P_max, P_r, and E denote the maximum polarization, remnant polarization, and applied electric field (E-field), respectively. According to Eqs. (1–3), it is suggested that a dielectric material with a large ΔP (= P_max–P_r), high breakdown strength (BDS), and low P–E curve hysteresis would achieve high W_rec and η [8]. Dielectric materials are categorized into four types based on the characteristics of their P–E curves: linear dielectrics (LDs), normal ferroelectrics (FEs), antiferroelectrics (AFEs), and relaxor ferroelectrics (RFEs) [9]. LDs exhibit a linear relationship between E-field and induced polarization [10]. Despite this, their low P_max results in poor ESP. While FEs can achieve high P_max, the elevated P_r and substantial P–E hysteresis lead to poor P_r and η. Lead-containing AFEs, although possessing higher P_r, undergo an E-field-driven AFE-FE phase transition during electrical loading, resulting in lower η and a strain mutation at the critical E-field [11]. Consequently, RFEs outperform the other three types of dielectrics in terms of integrated ESP [12, 13].

The ESP of (Bi_0.5Na_0.5)TiO₃ (BNT)-based bulk RFE ceramics has been extensively investigated in recent years [5, 6]. Figure 1a presents the W_rec of BNT-based ceramics plotted against the applied E-field, and Table S1 (refer to Supporting Information) summarizes the composition, maximum applied E-field (E_max), W_rec, and η for compared BNT-based bulk ceramics. In Fig. 1a, it is evident that W_rec generally increases with the applied E-field. Consequently, reducing permittivity (ε_r) and enhancing BDS emerge as effective strategies for enhancing the ESP of BNT-based ceramics. While efforts to reduce permittivity and improve BDS are relatively comparable, two critical challenges have been overlooked for an extended period. (1) Although increasing BDS enhances material ES capacity, working with strong E-fields poses challenges for miniaturization and integration. Operation at high fields (> 500 kV cm⁻¹) not only requires connecting the transformer system to the dielectric ES ceramic but also compromises the overall insulation performance of the system [14, 15]. This increases the system’s cost while reducing its safety. Finding ceramic capacitors with high W_rec and η under low E-fields (300 kV cm⁻¹) can also be challenging. Therefore, it is imperative to explore innovative dielectric ceramics with high W_rec and η under moderate E-fields, as depicted in Fig. 1a. (2) Many studies have opted to delay saturation polarization to reduce ε_r and improve BDS [16, 17]. However, arbitrarily reducing ε_r can be detrimental. According to Eq. (4):

$$P = \varepsilon_{0} \varepsilon_{r} E$$

(4)

where ε₀ is the vacuum permittivity. Extremely low ε_r diminishes macroscopic polarization, negatively impacting W_rec according to Eq. (2). Conversely, extremely high ε_r can lead to rapid polarization saturation and dielectric breakdown at low E-fields, reducing η. Therefore, understanding how to scientifically tailor ε_r is crucial. In Fig. 1b, we employed Eq. (5) to calculate the ESP of LD materials:

$$W_{{{\text{cal}}}} = \frac{{\varepsilon_{0} \varepsilon_{r} E^{2} }}{2}$$

(5)

where W_cal is the theoretical calculated value of W_rec. As per Eq. (5), ES density is positively correlated with permittivity. However, RFEs are not linear dielectrics and exhibit substantial hysteresis, resulting in their W_rec typically being lower than W_cal. BDS, on the other hand, is associated with permittivity, with higher permittivity making breakdown easier under low E-fields, leading to lower ESP. To achieve ultrahigh ESP under a moderate E-field of 500 kV cm⁻¹, permittivity should be adjusted to around 1200, as shown in Fig. 1b.

Prior investigations suggest that lead-free bulk ES ceramics, comprising BaTiO₃ (BT)-based [18, 19], (K_0.5Na_0.5)NbO₃ (KNN)-based [20, 21], and BNT-based materials, exhibit high P_max values [5, 22,23,24]. Particularly within BNT-based materials, P_max can surpass 40 μC cm⁻² [18, 25, 26]. However, the strong hybridization between the 6s orbital of Bi³⁺ ion and the 2p orbital of O^2– ion not only yields high P_max but also high P_r [27]. In our previous study, we introduced SrTiO₃ (ST) into BNT-based ceramics, where Sr²⁺ entered the A-site, inducing A-site disorder [28]. Although this reduces P_max, it significantly decreases ε_r. In this investigation, we counterbalance the negative impact on polarization by incorporating Bi(Mg_2/3Nb_1/3)O₃ (BMN). On the one hand, this is conducive to enhancing P_max by introducing Nb⁵⁺ ions at the B-site and increasing the content of Bi³⁺ ions at the A-site. Calculations indicate that the activation energy (E_a) of grain boundaries rises with the increase in ST-BMN content. On the other hand, elevated E_a improves the material’s insulating capabilities, as depicted in Fig. 1c. Additionally, the introduction of different ions into the A-site and B-site effectively disrupts long-range order through local E-field fluctuations [29, 30]. Based on the findings of T. Karthik et al. and **g et al., it can be shown that (Bi_0.5Na_0.4K_0.1)TiO₃ (referred to as BNKT) is situated in close proximity to the morphotropic phase boundary (MPB) [31, 32]. This particular positioning results in the manifestation of lower coercive field (E_c) and bigger polarization when compared to BNT. BNKT ceramics located near the MPB can transform macroscopic ferroelectric domains into polar nanoregions (PNRs), fostering increased η, and enhancing the materials’ ESP. Consequently, under a moderate E-field, the (1–x)BNKT−x(2/3ST-1/3BMN) ceramics are anticipated to demonstrate superior ESP. Following the outlined strategy in Fig. 1, ST-BMN has been employed to modulate the domain, heighten the E_a of grain boundaries, and adjust the ε_r to approximately 1200. This approach aims to produce ceramic capacitors showcasing exceptional ESP within the range of moderate E-fields (300–500 kV cm⁻¹). Ultimately, a breakthrough in the performance of BNT-based materials has been achieved, attaining a W_rec of 7.19 J cm⁻³ and an ultrahigh η of 93.9% under a moderate E-field of 460 kV cm⁻¹, along with outstanding thermal stability spanning a temperature range of 30–140 °C.

2 Experimental Section

2.1 Sample Preparation

The conventional solid-state reaction technique, combined with the viscous polymer process, was employed for the fabrication of (1–x)BNKT−x(2/3ST-1/3BMN) ceramics, abbreviated as B-xSB, with x values of 0.35, 0.40, 0.45, and 0.50. The reactions and sintering were carried out at 880 and 1150 °C, respectively, for a duration of 2 h. Further details on the experimental procedures, encompassing sample preparation, structural characterization, and assessments of dielectric, ferroelectric, and ES properties, are provided in the Supplementary Information.

2.2 Structural Characterization

The phase structure was thoroughly examined using X-ray diffraction (XRD, Panalytical, Cambridge, UK) in the range of 10°–120°, with a swee** rate of 2° min⁻¹, a working voltage of 45 kV, and a working current of 40 mA (operating conditions: Cu-Kα, λ = 1.5418 Å). Prior to testing, the sintered ceramic samples were ground into powders and annealed at 500 °C for 4 h to alleviate internal stress. The refinement of the phase structure was conducted using the FULLPROF software package (version 2000). The microstructure of the sintered samples was visualized using a scanning electron microscope (SEM, Quanta, FEG 250, FEI, Hillsboro, USA). Dark-field images, selected area electron diffraction (SAED) patterns, and nanoscale high-resolution images were acquired using a specialized aberration-corrected transmission electron microscope (AC-TEM, Talos F200X, FEI, USA).

2.3 Dielectric, Ferroelectric, and ES Properties Measurement

The temperature-dependent dielectric properties, encompassing ε_r and dielectric loss tangent (tanδ) of the investigated samples, were assessed using a multi-frequency LCR meter (E4980A, Agilent, Palo Alto, USA). The test parameters included a temperature range of 30–400 °C, a heating rate of 2 °C min⁻¹, and test frequencies spanning 0.3–1000 kHz, respectively. P–E hysteresis loops and J–E curves for all samples were acquired using the Sawyer–Tower circuit (TF analyzer 2000, Aachen, Germany). Prior to the first-order reversal curve (FORC) and charge–discharge testing, a 2-mm diameter electrode was affixed to the surface of the samples, each with a thickness of approximately 100 μm. The direct ESP of the ceramic samples was evaluated using a charge–discharge testing system (CFD-003, TG Technology, Shanghai, China). W_dis and power density (P_D) were computed employing the formulas ${W}_{{\text{dis}}}=R\int {i}^{2}\left(t\right){\text{d}}t/V$ and ${P}_{D}=E{I}_{{\text{max}}}/2S$, where i(t), V, I_max, R, and S represent the time-dependent discharge current, effective volume, maximum discharge current, load resistance, and electrode area, respectively. FORC measurements were conducted using modulated triangle waveforms with a standard ferroelectric testing device (TF Analyzer 2000, aixACCT, Aachen, Germany). The Preisach density representing the distribution of FORC data was calculated from the descending segment of the primary hysteresis loop using a differential approach, as described by the following equation [33]:

$$\rho_{{{\text{FORC}}}}^{ - } \left( {E,E_{r} } \right) = \frac{{\partial^{2} P_{{{\text{FORC}}}}^{ - } \left( {E,E_{r} } \right)}}{{\partial E_{r} \partial E}}$$

(5)

Here ${P}_{{\text{FORC}}}^{-}$ denotes the polarization in the FORC analysis, E_r represents the reversal electric field, E is the actual applied electric field, and ${\rho }_{{\text{FORC}}}^{-}$ signifies the Preisach density of the FORC distribution. The presence of the minus sign indicates that the FORC analysis commences from the descending branch of the primary hysteresis loop.

3 Results and Discussion

3.1 XRD Structural Characterization

The XRD patterns of B-xSB ceramic powders, with scanning angles 2θ ranging from 20° to 70°, are presented in Fig. 2a. All component diffraction peaks align with the BNT PDF #46-0001. Additionally, traces of a second phase were detected, with diffraction peaks potentially coinciding with the PDF #32-0118 of Bi₂Ti₂O₇, consistent with the previous findings [34, 36]. Therefore, when the do** amount increases to 45%, the crystal lattice slightly expands. However, when the do** quantity is too low, it does not generate an apparent lattice expansion, consistent with the previous results by Wang et al. [37] and Sun et al. [38]. As x increases from 0.35 to 0.50, the content of R phase increases somewhat and then declines, as shown in Fig. 2e. The T phase to R phase ratio remains nearly constant. The preservation of a strong polar phase is beneficial for maintaining macroscopic polarization. Figure 2f depicts the evolution of (111) and (200) diffraction peaks as the temperature rises from 30 to 100 °C. Due to the thermal expansion of the crystal lattice, these two peaks shift only toward lower angles with increasing temperature. The shape of these two peaks remains unchanged across the temperature range, indicating the coexistence of R and T phases from room temperature (RT) to 100 °C.

3.2 Dielectric Properties

The phase evolutions of the B-xSB ceramics were further assessed through their dielectric properties. The temperature-dependent ε_r of B-xSB ceramic samples, measured at various frequencies, is illustrated in Fig. 2g. In this temperature range, each composition exhibits two dielectric anomalies, a common occurrence in BNT-based systems [12, 28, 32, 39]. The dielectric anomaly with high dielectric dispersion on the left is attributed to a normal dielectric relaxation, while the broad dielectric peak with low dielectric dispersion on the right is associated with a diffuse phase transition caused by the coexistence of R and T phases [40, 41] or a transformation from low-temperature PNRs to high-temperature PNRs [28, 42,43,44]. The dielectric anomaly peak on the left shifts toward higher temperatures with increasing frequency, indicative of a typical RFE characteristic [45, 46]. The temperature (T_m) at which the maximum permittivity (ε_m) occurs demonstrates a clear shift toward lower values as x increases from 0.35 to 0.5. This behavior can be attributed to the disruption of the long-range ferroelectric order and the simultaneous increase in PNRs content. Notably, ε_r decreases with increasing BMN concentration, reaching the lowest value for the x = 0.50 composition. The curves of ε_r/ε₅₀ (where ε₅₀ is the ε_r measured at 1 kHz and 50 °C) with increasing temperature are depicted in Fig. 2h. The x = 0.50 composition exhibits the lowest and most stable ε_r/ε₅₀, signifying superior temperature stability. Due to its low ε_r and excellent temperature stability, this composition holds great appeal for dielectric capacitor applications.

3.3 Surface Microstructures

SEM was employed to unveil the microstructures of B-xSB ceramics. In Fig. 2i, the average grain size (AGS) and density of B-xSB ceramics are depicted. The AGS and density exhibit slight variations with increasing BMN concentration, measuring between 1.60 and 1.68 μm and between 5.62 and 5.68 g cm⁻³, respectively. The surface morphologies of B-xSB ceramic samples, shown in Fig. 3a1–d1, reveal dense structures with minimal porosity. While no obvious second phase is observed in Fig. 3a1–b1, a small amount of second phase is apparent in Fig. 3c1–d1. As suggested by the XRD data, these second-phase materials are highly correlated to an oxide formed by the precipitation of Bi and Ti. This phenomenon of Bi precipitation is a recurring observation in BNT-based materials. Despite our concerted efforts to mitigate Bi precipitation during the sintering process through various methods, a minor amount of precipitation remains. It is important to note that similar observations of Bi precipitation have been documented in prior studies focusing on BNT-based materials [34, Full size image

Combining surface morphology and permittivity, we simulated the applied E-field to investigate potential distribution and local E-field distribution. SEM was utilized to individually portray grains and grain boundaries, and the ε_r intensity map is provided in Fig. 3a3–d3. Figure 3a4–d4 illustrates the potential distribution after simulating an external E-field of 150 kV cm⁻¹ downward. It is evident that as x increases, the potential difference between grains decreases significantly. As shown in Fig. 3a5–d5 (local E-field distribution), the regions represented by white circles exhibit the greatest potential difference and are more likely to experience breakdown, particularly at grain boundaries, elucidating the ceramics' susceptibility to grain boundary breakdown. When x = 0.50, the breakdown resistance performance improves. Moreover, the impedance of B-xSB ceramics was measured between 430 and 530 °C, as depicted in Fig. 3a6–d6. The grain boundary resistance was calculated using the (CR)(CR) model fitting, and E_a was determined using the Arrhenius formula [47]:

$$\sigma = A \cdot e^{{\frac{{ - E_{a} }}{{k_{B} \cdot T}}}}$$

(6)

where σ is conductivity, A is a constant, k_B is the Boltzmann constant, and T is temperature. Taking the derivative on both sides of the formula yields E_a. The results indicate that as ST-BMN concentrations increase, E_a rises from 0.90 eV (x = 0.35) to 1.21 eV (x = 0.50). The larger E_a inhibits carriers from crossing grain boundaries, effectively enhancing material insulation. These findings lay the groundwork for improving BDS.

3.4 Nanoscale Microstructures

The nanoscale microstructures of the x = 0.50 composition were meticulously examined using an AC-TEM. The bright-field image of a sample prepared through focused ion beam (FIB) is presented in Fig. 4a. High-resolution (HR)-TEM images of the x = 0.50 composition are detailed in Fig. 4b, where the distribution of cations is reflected by the imaging brightness. At the A-site, the brightness of Na⁺, Bi³⁺, K⁺, and Sr²⁺ cations is comparatively high, while at the B-site, the brightness of Nb⁵⁺, Mg²⁺, and Ti⁴⁺ cations is low. The brightness distribution is further illustrated in Fig. 4c insert, with high brightness in red and low brightness in blue. Figure 4c distinctly reveals the distribution of cations on the B-site (in yellow and green). The coordinates of the A-site atoms are extracted using the red region’s coordinates, and the theoretical coordinates of B-site atoms are calculated. Subsequently, the actual coordinates of B-site atoms are extracted based on the coordinates of the yellow and green regions, facilitating the simulation of the spontaneous polarization vector in each cell, as depicted in Fig. 4d. The background in Fig. 4d is an intensity map of polarization, showcasing the random orientation of spontaneous polarization vectors in each cell. Different colors represent polarization vectors in different directions, a characteristic of RFE, forming the basis for unique properties and the chemical foundation for the existence of PNRs. The strong polar and weak polar regions, depicted in dark blue and light blue backgrounds, respectively, are randomly distributed, and the dipoles within the white circle exhibit the same orientation, indicating PNRs. All PNRs have a diameter of less than 5 nm, indicating effective refinement by local E-field fluctuations, which enhances the ESP of the material [48,49,50].

Figure 4e and f shows selected area electron diffraction (SAED) patterns along [110]_pc and [111]_pc, where pc denotes pseudo-cubic. The presence of 1/2(ooo) superlattice points in [110] indicates the R phase, while the presence of 1/2(ooe) superlattice points in [111] indicates the T phase [51]. These patterns confirm that the composition with x = 0.50 possesses a phase structure consisting of coexisting R and T phases, consistent with the Rietveld fitting result of XRD. While TEM can reveal domain morphologies at the nanometer scale, it typically provides static results. In contrast, piezoresponse force microscopy (PFM) elucidates polarization switching behavior at the micrometer scale but faces challenges in capturing dynamic details, especially in relaxor ferroelectrics [52]. In these materials, PNRs rather than macroscopic domains respond to external driving fields. The switching behavior of individual PNR may vary due to local electric field variations, and historical responses can influence polarization switching behavior. FORC analysis is a valuable technique that can detect a range of residual states dependent on field history. It effectively represents the reaction of local structures in the presence of a uniform electric field and provides a statistical outcome of polarization switches in P–E loops. This approach incorporates spatial and historical polarization dynamics, offering direct insights into microstructures [53, 54]. FORCs of x = 0.35 and 0.50 ceramics were examined to illustrate macroscopically that in a sample with x = 0.50, all domains are converted into microscopic PNRs. Figure 4g and h–i depicts the principle and FORCs of ceramics with x = 0.35 and 0.50, respectively. In simpler terms, FORC is employed to quantify the number of polarization reversals: A higher value indicates more reversals, while a lower value signifies fewer reversals. The motion of domain barriers is recorded by tracking changes in domains through polarization reversals. In low E-fields, the low number of ferroelectric phases and the strong nonlinear polarization behavior of x = 0.35 ceramics at 30 kV cm⁻¹ indicate the inversion of ferroelectric domains and the movement of domain walls. This significant hysteresis is a consequence of weak ESP. Even when the sample with x = 0.50 is loaded to 150 kV cm⁻¹, there is no high-intensity distribution, indicating that ferroelectricity is diluted, RFE features are enhanced, and hysteresis is diminished. This is consistent with the exclusive discovery of tiny PNRs by TEM.

3.5 Ferroelectric and ES Performance

Subsequently, the ferroelectric and ES properties of B-xSB ceramic samples were thoroughly assessed. Figure 5a illustrates the unipolar P–E hysteresis loops of B-xSB samples with x = 0.35, 0.40, 0.45, and 0.50. Owing to the decrease in ε_r, the E_max that can be applied to the sample before electrical breakdown increases with the rising values of x. For B-xSB samples with x ranging from 0.35 to 0.50, the respective E_max values are 310, 330, 430, and 460 kV cm⁻¹ at a test frequency of 10 Hz. All B-xSB samples exhibited slim hysteresis loops, characteristic of RFE ceramics [9]. As x increases, the P–E loops become slimmer. Corresponding J–E curves are presented in Fig. 5b, revealing two distinct current peaks at 50 kV cm⁻¹. The RFE nature of B-xSB samples disrupts long-range ferroelectric order, resulting in the appearance of PNRs. When an applied E-field is present, PNRs become oriented but are unable to grow into macrodomains and return to random orientation when the E-field drops from E_max to zero. Consequently, the J–E curves exhibit twin peaks at low E-fields. Given the ruled-out AFE nature of BNT-based solid solutions [55, 56], the very slim P–E loops combined with double current peaks in J–E curves should be described as an AFE-like RFE (AL-RFE) characteristic [8, 57], rather than a relaxor AFE characteristic [58,68,69,70,71,72,73,74,75,76,77,78]. Details regarding the composition, E_max, W_rec, and η of the compared BNT-based bulk ceramics are summarized in Table S3. Clearly, the ESP of the x = 0.50 composition surpasses that of existing BNT-based ceramics. Generally, increasing the E-field improves W_rec. However, in the high E-field region, it appears that augmenting the electric field does not directly enhance W_rec. Although the E_max values of 0.8BNT-0.2Sr(Nb_0.5Al_0.5)O₃ [74] and 0.85[0.7BNT–0.3(Bi_0.1Sr_0.85)TiO₃]–0.15KNbO₃ [72] ceramics are 520 and 569 kV cm⁻¹, respectively, their W_rec values are 6.64 and 5.63 J cm⁻³, which are inferior to the W_rec of our ceramic. Conversely, even with high W_rec values of 7.02 and 6.3 J cm⁻³ at 390 and 420 kV cm⁻¹, the η values of 0.78BNT-0.22NaNbO₃ [65] and 0.85(0.94BNT-0.06BT)-0.15Bi(Mg_2/3Nb_1/3)O₃ [25] ceramics, at 85% and 80% respectively, are significantly lower than our ceramic (94%). Consequently, we achieve a comprehensive improvement in ESP with both high W_rec and high η in the x = 0.50 ceramic sample. In Fig. 5g, the ESP of the x = 0.50 ceramic is compared to that of various representative dielectric ceramic materials, including linear ST-based systems, AFE AgNbO₃ (AN)-based and NaNbO₃ (NN)-based systems, and RFE BT-based, KNN-based, BF-based, and BNT-based systems. Details of the composition, E_max, W_rec, and η of the compared systems, are summarized in Table S4. It is evident that linear ST-based systems often have low W_rec (< 4 J cm⁻³), but AFE AN-based and NN-based systems exhibit higher W_rec (4–7 J cm⁻³) and low η (50–90%). In contrast, RFE BT-based and KNN-based systems show medium W_rec (2–4 J cm⁻³) and fluctuating η (50–95%) under a moderate E-field. Although some BNT-based systems achieve higher W_rec and very high η (> 90%), the E_max has approached 520–600 kV cm⁻¹. In contrast, our x = 0.50 composition exhibits high W_rec (> 7 J cm⁻³) and high η (94%) simultaneously at a moderate E_max (460 kV cm⁻¹), indicating a comprehensive improvement in ESP. These findings demonstrate that by manipulating ε_r, we were able to create B-xSB ceramics with exceptional ESP in a moderate E-field. As a result, it has emerged as one of the most promising candidate materials for pulse ES ceramic devices.

Temperature stability is a critical criterion for pulse ES ceramic devices [79, 80]. The temperature stability of the ESP for the x = 0.50 composition was evaluated using temperature-dependent P–E and J–E curves, as illustrated in Fig. 5h. These curves were measured at 365 kV cm⁻¹ and 10 Hz, with temperatures ranging from 30 to 140 °C. Typically, in RFEs, P_r and E_c increase with rising temperature due to thermal activation of defects, which is detrimental to the stability of W_rec and η [7, 9, 81]. As the temperature increases, the P–E loops remain thin, and P_max decreases slightly from 42.7 to 37.0 μC cm⁻². The two current peaks indicated by the black arrows show almost no movement with rising temperature. These findings suggest that the ESP in the x = 0.50 composition exhibits good thermal stability. Despite a slight reduction in temperature, the W_rec of the x = 0.50 composition decreases from 5.64 J cm⁻³ at 30 °C to 5.06 J cm⁻³ at 140 °C, a 10% reduction, as shown in Fig. 5i. Because the P_r and E_c of the x = 0.50 composition remained reasonably steady, its η is extraordinarily high, with minimal variations ranging from 93.9 to 95.9%. The temperature-dependent ESP of the x = 0.50 composition is compared to other previously reported BNT-based ceramics in Fig. 5j–k [62, 64, 65, 74, 82, 83]. The constituents of these BNT-based ceramics are summarized in Table S5 (see Supplementary Information). The W_rec in those BNT-based ceramics typically declines to some extent as temperature rises, with none exceeding 4 J cm⁻³. In contrast, the W_rec of our x = 0.50 composition is significantly higher than the values of various BNT-based ceramics in the 30–140 °C temperature range, surpassing 5 J cm⁻³ at this temperature range, as shown in Fig. 5j. Furthermore, upon comparing the η, it is evident that the η of the x = 0.50 composition remains around 95%. Even with rising temperature, the trend is upward, as illustrated in Fig. 5k. In conclusion, in addition to the ultrahigh ESP at RT, the ESP of the x = 0.50 composition demonstrates ultrahigh W_rec and exceptional η over a wide temperature range, outperforming other BNT-based ceramics.

3.6 Charge–Discharge Performance

Finally, we evaluate the charge–discharge performance of the x = 0.50 composition, a pivotal criterion for pulse capacitor devices [84]. The sample thickness is 100 μm, and the electrode area is 3.14 mm². Charge–discharge tests employ a 100-Ω resistor. A dielectric ceramic with rapid charge/discharge characteristics is well-suited for pulse power supply. Room temperature electric current versus time (I–t) curves measured in an overdamped discharge mode are presented in Fig. 6a. The I_max increases with the escalating electric field. W_dis attains its peak value of 3.89 J cm⁻³ under 400 kV cm⁻¹, as depicted in Fig. 6b. The time at which W_dis releases 90% of its total energy, often denoted as t_0.9, is crucial for calculating discharge speed. At 100 kV cm⁻¹, the t_0.9 for the x = 0.50 composition is approximately 0.21 μs, diminishing with increasing electric field. At 400 kV cm⁻¹, t_0.9 is less than 0.12 μs. Figure 6c illustrates the temperature-dependent I–t curves from 40 to 140 °C, determined at overdamped discharge mode under an E-field of 300 kV cm⁻¹. The t_0.9 remains below 0.13 μs at all measured temperatures, as demonstrated in Fig. 6d. The I–t curves of underdamped discharge at different E-fields are presented in Fig. 6e, and the calculated current density (C_D) and power density (P_D) are displayed in Fig. 6f. The discharge of the x = 0.50 composition is confirmed to be complete after only two oscillations. At 400 kV cm⁻¹, C_D and P_D are exceedingly high at 767.5 A cm⁻² and 153.5 MW cm⁻³, respectively. These features indicate that the x = 0.50 composition ceramics exhibit significant potential for use in pulse power devices [7, 82].

4 Conclusions

In summary, we propose an approach to achieve optimal ESP under constrained E-field conditions by tailoring the ε_r. Ultimately, the x = 0.50 composition demonstrates an extraordinary η of 93.8% and an impressive W_rec of 7.19 J cm⁻³ at a moderate E-field. The temperature-dependent ESP of the x = 0.50 composition is also notably robust. Across the temperature range of 30–140 °C, W_rec consistently exceeds 5 J cm⁻³ with high efficiency (above 95%). In contrast with other BNT-based bulk ceramic capacitors, the B-0.5SB ceramic, with its exceptional ESP, undoubtedly stands out as a promising candidate for future ES devices. Moreover, the B-0.5SB ceramic exhibits an ultrahigh current density and power density, simulating real-world application scenarios. Although this study employed linear dielectrics as a model and acknowledges some discrepancies between research results and theoretical conclusions, it addresses a crucial research gap concerning the attainment of high ESP in a restricted E-field. To conclude, this strategy, involving the modification of ε_r, enhancement of insulating properties, and incorporation of domain engineering, proves effective. It is anticipated that these findings will contribute to and guide future research and development endeavors in the realm of ceramic capacitors.

References

Z. Yao, Z. Song, H. Hao, Z. Yu, M. Cao et al., Homogeneous/inhomogeneous-structured dielectrics and their energy-storage performances. Adv. Mater. 29, 1601727 (2017). https://doi.org/10.1002/adma.201601727
Article Google Scholar
J. Li, F. Li, Z. Xu, S. Zhang, Multilayer lead-free ceramic capacitors with ultrahigh energy density and efficiency. Adv. Mater. 30, 1802155 (2018). https://doi.org/10.1002/adma.201802155
Article Google Scholar
J. Li, Z. Shen, X. Chen, S. Yang, W. Zhou et al., Grain-orientation-engineered multilayer ceramic capacitors for energy storage applications. Nat. Mater. 19, 999–1005 (2020). https://doi.org/10.1038/s41563-020-0704-x
Article Google Scholar
L. Yang, X. Kong, F. Li, H. Hao, Z. Cheng et al., Perovskite lead-free dielectrics for energy storage applications. Prog. Mater. Sci. 102, 72–108 (2019). https://doi.org/10.1016/j.pmatsci.2018.12.005
Article Google Scholar
G. Wang, Z. Lu, Y. Li, L. Li, H. Ji et al., Electroceramics for high-energy density capacitors: current status and future perspectives. Chem. Rev. 121, 6124–6172 (2021). https://doi.org/10.1021/acs.chemrev.0c01264
Article Google Scholar
Z. Yang, H. Du, L. **, D. Poelman, High-performance lead-free bulk ceramics for electrical energy storage applications: design strategies and challenges. J. Mater. Chem. A 9, 18026–18085 (2021). https://doi.org/10.1039/D1TA04504K
Article Google Scholar
G. Liu, Y. Li, B. Guo, M. Tang, Q. Li et al., Ultrahigh dielectric breakdown strength and excellent energy storage performance in lead-free Barium titanate-based relaxor ferroelectric ceramics via a combined strategy of composition modification, viscous polymer processing, and liquid-phase sintering. Chem. Eng. J. 398, 125625 (2020). https://doi.org/10.1016/j.cej.2020.125625
Article Google Scholar
L. Zhang, R. **g, Y. Huang, Q. Hu, D.O. Alikin et al., Enhanced antiferroelectric-like relaxor ferroelectric characteristic boosting energy storage performance of (Bi_0.5Na_0.5)TiO₃-based ceramics via defect engineering. J. Materiomics 8, 527–536 (2022). https://doi.org/10.1016/j.jmat.2022.01.007
Article Google Scholar
L. **, F. Li, S. Zhang, Decoding the fingerprint of ferroelectric loops: comprehension of the material properties and structures. J. Am. Ceram. Soc. 97, 1–27 (2014). https://doi.org/10.1111/jace.12773
Article Google Scholar
H.Y. Zhou, X.Q. Liu, X.L. Zhu, X.M. Chen, CaTiO₃ linear dielectric ceramics with greatly enhanced dielectric strength and energy storage density. J. Am. Ceram. Soc. 101, 1999–2008 (2018). https://doi.org/10.1111/jace.15371
Article Google Scholar
H. Wang, Y. Liu, T. Yang, S. Zhang, Ultrahigh energy-storage density in antiferroelectric ceramics with field-induced multiphase transitions. Adv. Funct. Mater. 29, 1807321 (2019). https://doi.org/10.1002/adfm.201807321
Article Google Scholar
J. Lv, Q. Li, Y. Li, M. Tang, D. ** et al., Significantly improved energy storage performance of NBT-BT based ceramics through domain control and preparation optimization. Chem. Eng. J. 420, 129900 (2021). https://doi.org/10.1016/j.cej.2021.129900
Article Google Scholar
L. Zhang, M. Zhao, Y. Yang, Y. Li, M. Tang et al., Achieving ultrahigh energy density and ultrahigh efficiency simultaneously via characteristic regulation of polar nanoregions. Chem. Eng. J. 465, 142862 (2023). https://doi.org/10.1016/j.cej.2023.142862
Article Google Scholar
H. Palneedi, M. Peddigari, G.-T. Hwang, D.-Y. Jeong, J. Ryu, High-performance dielectric ceramic films for energy storage capacitors: progress and outlook. Adv. Funct. Mater. 28, 1803665 (2018). https://doi.org/10.1002/adfm.201803665
Article Google Scholar
L. Chen, H. Yu, J. Wu, S. Deng, H. Liu et al., Large energy capacitive high-entropy lead-free ferroelectrics. Nano-Micro Lett. 15, 65 (2023). https://doi.org/10.1007/s40820-023-01036-2
Article Google Scholar
J. Shi, Y. Zhao, J. He, T. Li, F. Zhu et al., Deferred polarization saturation boosting superior energy-storage efficiency and density simultaneously under moderate electric field in relaxor ferroelectrics. ACS Appl. Energy Mater. 5, 3436–3446 (2022). https://doi.org/10.1021/acsaem.1c04017
Article Google Scholar
J. Zhao, T. Hu, Z. Fu, Z. Pan, L. Tang et al., Delayed polarization saturation induced superior energy storage capability of BiFeO₃-based ceramics via introduction of non-isovalent ions. Small 19, e2206840 (2023). https://doi.org/10.1002/smll.202206840
Article Google Scholar
W. Wang, L. Zhang, R. **g, Q. Hu, D.O. Alikin et al., Enhancement of energy storage performance in lead-free Barium titanate-based relaxor ferroelectrics through a synergistic two-step strategy design. Chem. Eng. J. 434, 134678 (2022). https://doi.org/10.1016/j.cej.2022.134678
Article Google Scholar
W. Wang, L. Zhang, C. Li, D.O. Alikin, V.Y. Shur et al., Effective strategy to improve energy storage properties in lead-free (Ba_0.8Sr_0.2)TiO₃-Bi(Mg_0.5Zr_0.5)O₃ relaxor ferroelectric ceramics. Chem. Eng. J. 446, 137389 (2022). https://doi.org/10.1016/j.cej.2022.137389
Article Google Scholar
X. Ren, L. **, Z. Peng, B. Chen, X. Qiao et al., Regulation of energy density and efficiency in transparent ceramics by grain refinement. Chem. Eng. J. 390, 124566 (2020). https://doi.org/10.1016/j.cej.2020.124566
Article Google Scholar
Z. Yang, F. Gao, H. Du, L. **, L. Yan et al., Grain size engineered lead-free ceramics with both large energy storage density and ultrahigh mechanical properties. Nano Energy 58, 768–777 (2019). https://doi.org/10.1016/j.nanoen.2019.02.003
Article Google Scholar
G. Liu, Y. Li, M. Shi, L. Yu, P. Chen et al., An investigation of the dielectric energy storage performance of Bi(Mg_2/3Nb_1/3)O₃-modifed BaTiO₃ Pb-free bulk ceramics with improved temperature/frequency stability. Ceram. Int. 45, 19189–19196 (2019). https://doi.org/10.1016/j.ceramint.2019.06.166
Article Google Scholar
G. Liu, Y. Li, J. Gao, D. Li, L. Yu et al., Structure evolution, ferroelectric properties, and energy storage performance of CaSnO₃ modified BaTiO₃-based Pb-free ceramics. J. Alloys Compd. 826, 154160 (2020). https://doi.org/10.1016/j.jallcom.2020.154160
Article Google Scholar
T. Wang, L. Zhang, A. Zhang, J. Liu, L. Kong et al., Synergistic enhanced energy storage performance of NBT-KBT ceramics by K_0.5Na_0.5NbO₃ composition design. J. Alloys Compd. 948, 169725 (2023). https://doi.org/10.1016/j.jallcom.2023.169725
Article Google Scholar
B. Guo, Y. Yan, M. Tang, Z. Wang, Y. Li et al., Energy storage performance of Na_0.5Bi_0.5TiO₃ based lead-free ferroelectric ceramics prepared via non-uniform phase structure modification and rolling process. Chem. Eng. J. 420, 130475 (2021). https://doi.org/10.1016/j.cej.2021.130475
Article Google Scholar
G. Liu, Y. Wang, G. Han, J. Gao, L. Yu et al., Enhanced electrical properties and energy storage performances of NBT-ST Pb-free ceramics through glass modification. J. Alloys Compd. 836, 154961 (2020). https://doi.org/10.1016/j.jallcom.2020.154961
Article Google Scholar
L. Zhang, S. Cao, Y. Li, R. **g, Q. Hu et al., Achieving ultrahigh energy storage performance over a broad temperature range in (Bi_0.5Na_0.5)TiO₃-based eco-friendly relaxor ferroelectric ceramics via multiple engineering processes. J. Alloys Compd. 896, 163139 (2022). https://doi.org/10.1016/j.jallcom.2021.163139
Article Google Scholar
G. Liu, J. Dong, L. Zhang, Y. Yan, R. **g et al., Phase evolution in (1–x)(Na_0.5Bi_0.5)TiO₃₋_xSrTiO₃ solid solutions: a study focusing on dielectric and ferroelectric characteristics. J. Materiomics 6, 677–691 (2020). https://doi.org/10.1016/j.jmat.2020.05.005
Article Google Scholar
S. Wu, B. Fu, J. Zhang, H. Du, Q. Zong et al., Superb energy storage capability for NaNbO₃-based ceramics featuring labyrinthine submicro-domains with clustered lattice distortions. Small 19, e2303915 (2023). https://doi.org/10.1002/smll.202303915
Article Google Scholar
H. Wang, S. Wu, B. Fu, J. Zhang, H. Du et al., Hierarchically polar structures induced superb energy storage properties for relaxor Bi_0.5Na_0.5TiO₃-based ceramics. Chem. Eng. J. 471, 144446 (2023). https://doi.org/10.1016/j.cej.2023.144446
Article Google Scholar
T. Karthik, S. Asthana, Enhanced mechanical and ferroelectric properties through grain size refinement in site specific substituted lead free Na_0.5–xK x Bi_0.5 TiO₃ (x = 0–0.10) ceramics. Mater. Lett. 190, 273–275 (2017). https://doi.org/10.1016/j.matlet.2017.01.025
Article Google Scholar
R. **g, L. Zhang, Q. Hu, D.O. Alikin, V.Y. Shur et al., Phase evolution and relaxor to ferroelectric phase transition boosting ultrahigh electrostrains in (1–x)(Bi_1/2Na_1/2)TiO_3-_x(Bi_1/2K_1/2)TiO₃ solid solutions. J. Materiomics 8, 335–346 (2022). https://doi.org/10.1016/j.jmat.2021.09.002
Article Google Scholar
C. Wang, X. Yang, Z. Wang, C. He, X. Long, Investigation of switching behavior of acceptor-doped ferroelectric ceramics. Acta Mater. 170, 100–108 (2019). https://doi.org/10.1016/j.actamat.2019.03.033
Article Google Scholar
T. Kainz, M. Naderer, D. Schütz, O. Fruhwirth, F.A. Mautner et al., Solid state synthesis and sintering of solid solutions of BNT–xBKT. J. Eur. Ceram. Soc. 34, 3685–3697 (2014). https://doi.org/10.1016/j.jeurceramsoc.2014.04.040
Article Google Scholar
Y. Liu, Y. Li, Z. Zheng, W. Kang, K. ** et al., Dielectric temperature stability of Nb-modified Bi_0.5(Na_0.78K_0.22)_0.5TiO₃ lead-free ceramics. Ceram. Int. 47, 4933–4936 (2021). https://doi.org/10.1016/j.ceramint.2020.10.067
Article Google Scholar
R.D. Shannon, Revised effective ionic radii and systematic studies of interatomic distances in halides and chalcogenides. Acta Crystallogr. Sect. A 32, 751–767 (1976). https://doi.org/10.1107/s0567739476001551
Article Google Scholar
T. Wang, L. **, C. Li, Q. Hu, X. Wei, Relaxor ferroelectric BaTiO₃–Bi(Mg_2/3Nb_1/3)O₃ ceramics for energy storage application. J. Am. Ceram. Soc. 98, 559–566 (2015). https://doi.org/10.1111/jace.13325
Article Google Scholar
C. Sun, X. Chen, J. Shi, F. Pang, X. Dong et al., Simultaneously with large energy density and high efficiency achieved in NaNbO₃-based relaxor ferroelectric ceramics. J. Eur. Ceram. Soc. 41, 1891–1903 (2021). https://doi.org/10.1016/j.jeurceramsoc.2020.10.049
Article Google Scholar
L. **, W. Luo, L. Wang, Y. Tian, Q. Hu et al., High thermal stability of electric field-induced strain in (1–x)(Bi_0.5Na_0.5)TiO₃-xBa_0.85Ca_0.15Ti_0.9Zr_0.1O₃ lead-free ferroelectrics. J. Eur. Ceram. Soc. 39, 277–286 (2019). https://doi.org/10.1016/j.jeurceramsoc.2018.09.019
Article Google Scholar
W. Jo, S. Schaab, E. Sapper, L.A. Schmitt, H.-J. Kleebe et al., On the phase identity and its thermal evolution of lead free (Bi_1/2Na_1/2)TiO₃^-6 mol% BaTiO₃. J. Appl. Phys. 110, 074106 (2011). https://doi.org/10.1063/1.3645054
Article Google Scholar
Y. Hiruma, Y. Imai, Y. Watanabe, H. Nagata, T. Takenaka, Large electrostrain near the phase transition temperature of (Bi_0.5Na_0.5)TiO₃–SrTiO₃ ferroelectric ceramics. Appl. Phys. Lett. 92, 262904 (2008). https://doi.org/10.1063/1.2955533
Article Google Scholar
H. Zhang, P. Xu, E. Patterson, J. Zang, S. Jiang et al., Preparation and enhanced electrical properties of grain-oriented (Bi_1/2Na_1/2)TiO₃-based lead-free incipient piezoceramics. J. Eur. Ceram. Soc. 35, 2501–2512 (2015). https://doi.org/10.1016/j.jeurceramsoc.2015.03.012
Article Google Scholar
J. Zang, W. Jo, H. Zhang, J. Rödel, Bi_1/2Na_1/2TiO₃–BaTiO₃ based thick-film capacitors for high-temperature applications. J. Eur. Ceram. Soc. 34, 37–43 (2014). https://doi.org/10.1016/j.jeurceramsoc.2013.07.020
Article Google Scholar
G. Viola, H. Ning, X. Wei, M. Deluca, A. Adomkevicius et al., Dielectric relaxation, lattice dynamics and polarization mechanisms in Bi_0.5Na_0.5TiO₃-based lead-free ceramics. J. Appl. Phys. 114, 014107 (2013). https://doi.org/10.1063/1.4812383
Article Google Scholar
A.A. Bokov, Z.-G. Ye, Recent progress in relaxor ferroelectrics with perovskite structure. J. Mater. Sci. 41, 31–52 (2006). https://doi.org/10.1007/s10853-005-5915-7
Article Google Scholar
V.V. Shvartsman, D.C. Lupascu, Lead-free relaxor ferroelectrics. J. Am. Ceram. Soc. 95, 1–26 (2012). https://doi.org/10.1111/j.1551-2916.2011.04952.x
Article Google Scholar
T. Wang, J. Hu, H. Yang, L. **, X. Wei et al., Dielectric relaxation and Maxwell-Wagner interface polarization in Nb₂O₅ doped 06.5BiFeO₃–0.35BaTiO₃ ceramics. J. Appl. Phys. 121, 084103 (2017). https://doi.org/10.1063/1.4977107
Article Google Scholar
L.E. Cross, Relaxor ferroelectrics. Ferroelectrics 76, 241–267 (1987). https://doi.org/10.1080/00150198708016945
Article Google Scholar
H. Pan, S. Lan, S. Xu, Q. Zhang, H. Yao et al., Ultrahigh energy storage in superparaelectric relaxor ferroelectrics. Science 374, 100–104 (2021). https://doi.org/10.1126/science.abi7687
Article Google Scholar
H. Pan, F. Li, Y. Liu, Q. Zhang, M. Wang et al., Ultrahigh-energy density lead-free dielectric films via polymorphic nanodomain design. Science 365, 578–582 (2019). https://doi.org/10.1126/science.aaw8109
Article Google Scholar
C. Zhu, Z. Cai, B. Luo, L. Guo, L. Li et al., High temperature lead-free BNT-based ceramics with stable energy storage and dielectric properties. J. Mater. Chem. A 8, 683–692 (2020). https://doi.org/10.1039/c9ta10347c
Article Google Scholar
L. Zhang, R. **g, Y. Huang, Q. Hu, D.O. Alikin et al., Ultrahigh electrostrictive effect in potassium sodium niobate-based lead-free ceramics. J. Eur. Ceram. Soc. 42, 944–953 (2022). https://doi.org/10.1016/j.jeurceramsoc.2021.11.037
Article Google Scholar
W. Wang, L. Zhang, W. Shi, Y. Yang, D. Alikin et al., Enhanced energy storage properties in lead-free (Na_0.5Bi_0.5)_0.7Sr_0.3TiO₃-based relaxor ferroelectric ceramics through a cooperative optimization strategy. ACS Appl. Mater. Interfaces 15, 6990–7001 (2023). https://doi.org/10.1021/acsami.2c21969
Article Google Scholar
W. Wang, L. Zhang, Y. Yang, W. Shi, Y. Huang et al., Enhancing energy storage performance in Na_0.5Bi_0.5TiO₃-based lead-free relaxor ferroelectric ceramics along a stepwise optimization route. J. Mater. Chem. A 11, 2641–2651 (2023). https://doi.org/10.1039/D2TA09395B
Article Google Scholar
W. Jo, T. Granzow, E. Aulbach, J. Rödel, D. Damjanovic, Origin of the large strain response in (K_0.5Na_0.5)NbO₃-modified (Bi_0.5Na_0.5)TiO₃–BaTiO₃ lead-free piezoceramics. J. Appl. Phys. 105, 094102 (2009). https://doi.org/10.1063/1.3121203
Article Google Scholar
G. Viola, Y. Tian, C. Yu, Y. Tan, V. Koval et al., Electric field-induced transformations in bismuth sodium titanate-based materials. Prog. Mater. Sci. 122, 100837 (2021). https://doi.org/10.1016/j.pmatsci.2021.100837
Article Google Scholar
W. Shi, L. Zhang, R. **g, Q. Hu, X. Zeng et al., Relaxor antiferroelectric-like characteristic boosting enhanced energy storage performance in eco-friendly (Bi_0.5Na_0.5)TiO₃-based ceramics. J. Eur. Ceram. Soc. 42, 4528–4538 (2022). https://doi.org/10.1016/j.jeurceramsoc.2022.04.057
Article Google Scholar
N. Luo, K. Han, M.J. Cabral, X. Liao, S. Zhang et al., Constructing phase boundary in AgNbO₃ antiferroelectrics: pathway simultaneously achieving high energy density and efficiency. Nat. Commun. 11, 4824 (2020). https://doi.org/10.1038/s41467-020-18665-5
Article Google Scholar
A. **e, R. Zuo, Z. Qiao, Z. Fu, T. Hu et al., NaNbO₃-(Bi_0.5Li_0.5)TiO₃ lead-free relaxor ferroelectric capacitors with superior energy-storage performances via multiple synergistic design. Adv. Energy Mater. 11, 2101378 (2021). https://doi.org/10.1002/aenm.202101378
Article Google Scholar
J. Jiang, X. Meng, L. Li, S. Guo, M. Huang et al., Ultrahigh energy storage density in lead-free relaxor antiferroelectric ceramics via domain engineering. Energy Storage Mater. 43, 383–390 (2021). https://doi.org/10.1016/j.ensm.2021.09.018
Article Google Scholar
Q. Hu, X. Wei, Abnormal phase transition and polarization mismatch phenomena in BaTiO₃-based relaxor ferroelectrics. J. Adv. Dielect. 9, 1930002 (2019). https://doi.org/10.1142/s2010135x19300020
Article Google Scholar
F. Yan, K. Huang, T. Jiang, X. Zhou, Y. Shi et al., Significantly enhanced energy storage density and efficiency of BNT-based perovskite ceramics via A-site defect engineering. Energy Storage Mater. 30, 392–400 (2020). https://doi.org/10.1016/j.ensm.2020.05.026
Article Google Scholar
X. Zhao, W. Bai, Y. Ding, L. Wang, S. Wu et al., Tailoring high energy density with superior stability under low electric field in novel (Bi_0.5Na_0.5)TiO₃-based relaxor ferroelectric ceramics. J. Eur. Ceram. Soc. 40, 4475–4486 (2020). https://doi.org/10.1016/j.jeurceramsoc.2020.05.078
Article Google Scholar
D. Li, Y. Lin, Q. Yuan, M. Zhang, L. Ma et al., A novel lead-free Na_0.5Bi_0.5TiO₃-based ceramic with superior comprehensive energy storage and discharge properties for dielectric capacitor applications. J. Materiomics 6, 743–750 (2020). https://doi.org/10.1016/j.jmat.2020.06.005
Article Google Scholar
H. Qi, R. Zuo, Linear-like lead-free relaxor antiferroelectric (Bi_0.5Na_0.5)TiO₃–NaNbO₃ with giant energy-storage density/efficiency and super stability against temperature and frequency. J. Mater. Chem. A 7, 3971–3978 (2019). https://doi.org/10.1039/C8TA12232F
Article Google Scholar
H. Yang, F. Yan, Y. Lin, T. Wang, Novel strontium titanate-based lead-free ceramics for high-energy storage applications. ACS Sustain. Chem. Eng. 5, 10215–10222 (2017). https://doi.org/10.1021/acssuschemeng.7b02203
Article Google Scholar
Y. Huang, L. Zhang, R. **g, Q. Hu, D.O. Alikin et al., Thermal stability of dielectric and energy storage performances of Ca-substituted BNTZ ferroelectric ceramics. Ceram. Int. 47, 6298–6309 (2021). https://doi.org/10.1016/j.ceramint.2020.10.208
Article Google Scholar
G. Liu, J. Dong, L. Zhang, L. Yu, F. Wei et al., Na_0.25Sr_0.5Bi_0.25TiO₃ relaxor ferroelectric ceramic with greatly enhanced electric storage property by a B-site ion do**. Ceram. Int. 46, 11680–11688 (2020). https://doi.org/10.1016/j.ceramint.2020.01.199
Article Google Scholar
R. Kang, Z. Wang, X. Lou, W. Liu, P. Shi et al., Energy storage performance of Bi_0.5Na_0.5TiO₃-based relaxor ferroelectric ceramics with superior temperature stability under low electric fields. Chem. Eng. J. 410, 128376 (2021). https://doi.org/10.1016/j.cej.2020.128376
Article Google Scholar
G. Liu, L. Hu, Y. Wang, Z. Wang, L. Yu et al., Investigation of electrical and electric energy storage properties of La-doped Na_0.3 Sr_0.4Bi_0.3TiO₃ based Pb-free ceramics. Ceram. Int. 46, 19375–19384 (2020). https://doi.org/10.1016/j.ceramint.2020.04.280
Article Google Scholar
L. Yu, J. Dong, M. Tang, Y. Liu, F. Wu et al., Enhanced electrical energy storage performance of Pb-free A-site La³⁺-doped 0.85Na_0.5Bi_0.5TiO₃–0.15CaTiO₃ ceramics. Ceram. Int. 46, 28173–28182 (2020). https://doi.org/10.1016/j.ceramint.2020.07.316
Article Google Scholar
X. Zhang, D. Hu, Z. Pan, X. Lv, Z. He et al., Enhancement of recoverable energy density and efficiency of lead-free relaxor-ferroelectric BNT-based ceramics. Chem. Eng. J. 406, 126818 (2021). https://doi.org/10.1016/j.cej.2020.126818
Article Google Scholar
X. Qiao, F. Zhang, D. Wu, B. Chen, X. Zhao et al., Superior comprehensive energy storage properties in Bi_0.5Na_0.5TiO₃-based relaxor ferroelectric ceramics. Chem. Eng. J. 388, 124158 (2020). https://doi.org/10.1016/j.cej.2020.124158
Article Google Scholar
F. Yan, X. Zhou, X. He, H. Bai, S. Wu et al., Superior energy storage properties and excellent stability achieved in environment-friendly ferroelectrics via composition design strategy. Nano Energy 75, 105012 (2020). https://doi.org/10.1016/j.nanoen.2020.105012
Article Google Scholar
D. Hu, Z. Pan, X. Zhang, H. Ye, Z. He et al., Greatly enhanced discharge energy density and efficiency of novel relaxation ferroelectric BNT–BKT-based ceramics. J. Mater. Chem. C 8, 591–601 (2020). https://doi.org/10.1039/C9TC05528B
Article Google Scholar
L. Yang, X. Kong, Z. Cheng, S. Zhang, Ultra-high energy storage performance with mitigated polarization saturation in lead-free relaxors. J. Mater. Chem. A 7, 8573–8580 (2019). https://doi.org/10.1039/c9ta01165j
Article Google Scholar
T. Li, P. Chen, F. Li, C. Wang, Energy storage performance of Na_0.5Bi_0.5TiO₃-SrTiO₃ lead-free relaxors modified by AgNb_0.85Ta_0.15O₃. Chem. Eng. J. 406, 127151 (2021). https://doi.org/10.1016/j.cej.2020.127151
Article Google Scholar
Z. Jiang, H. Yang, L. Cao, Z. Yang, Y. Yuan et al., Enhanced breakdown strength and energy storage density of lead-free Bi05Na05TiO3-based ceramic by reducing the oxygen vacancy concentration. Chem. Eng. J. 414, 128921 (2021). https://doi.org/10.1016/j.cej.2021.128921
Article Google Scholar
Z. Yang, H. Du, L. **, Q. Hu, H. Wang et al., Realizing high comprehensive energy storage performance in lead-free bulk ceramics via designing an unmatched temperature range. J. Mater. Chem. A 7, 27256–27266 (2019). https://doi.org/10.1039/C9TA11314B
Article Google Scholar
G. Zhang, P. Liu, B. Fan, H. Liu, Y. Zeng et al., Large energy density in Ba doped Pb_0.97La_0.02(Zr_0.65Sn_0.3Ti_0.05)O₃ antiferroelectric ceramics with improved temperature stability. IEEE Trans. Dielectr. Electr. Insul. 24, 744–748 (2017). https://doi.org/10.1109/TDEI.2017.006161
Article Google Scholar
L. **, W. Luo, L. Hou, Y. Tian, Q. Hu et al., High electric field-induced strain with ultra-low hysteresis and giant electrostrictive coefficient in Barium strontium titanate lead-free ferroelectrics. J. Eur. Ceram. Soc. 39, 295–304 (2019). https://doi.org/10.1016/j.jeurceramsoc.2018.09.005
Article Google Scholar
H. Ye, F. Yang, Z. Pan, D. Hu, X. Lv et al., Significantly improvement of comprehensive energy storage performances with lead-free relaxor ferroelectric ceramics for high-temperature capacitors applications. Acta Mater. 203, 116484 (2021). https://doi.org/10.1016/j.actamat.2020.116484
Article Google Scholar
A.K. Yadav, H. Fan, B. Yan, C. Wang, J. Ma et al., Enhanced storage energy density and fatigue free properties for 0.94Bi_0.50(Na_0.78K_0.22)_0.50Ti₁₋_x(Al_0.50Nb_0.50)xO₃–_0.06BaZrO₃ ceramics. Ceram. Int. 46, 17044–17052 (2020). https://doi.org/10.1016/j.ceramint.2020.03.292
Article Google Scholar
A. **e, H. Qi, R. Zuo, Achieving remarkable amplification of energy-storage density in two-step sintered NaNbO₃–SrTiO₃ antiferroelectric capacitors through dual adjustment of local heterogeneity and grain scale. ACS Appl. Mater. Interfaces 12, 19467–19475 (2020). https://doi.org/10.1021/acsami.0c00831
Article Google Scholar

Download references

Acknowledgements

This work was supported by the National Natural Science Foundation of China (Grant No. 51761145024), the Key Research and Development Program of Shaanxi (Program No. 2022KWZ-22), the Natural Science Basic Research Program of Shaanxi (Program No. 2023-JC-YB-441), the Youth Innovation Team of Shaanxi Universities, and the Fundamental Research Funds of Shaanxi Key Laboratory of Artificially-Structured Functional Materials and Devices (AFMD-KFJJ-21203). The research was made possible by Russian Science Foundation (Project No. 23-42-00116). The equipment of the Ural Center for Shared Use “Modern nanotechnology” Ural Federal University (Reg. No. 2968) which is supported by the Ministry of Science and Higher Education RF (Project No. 075-15-2021-677) was used. The SEM work was done at International Center for Dielectric Research (ICDR), **’an Jiaotong University, **’an, China. The authors also thank Shiyanjia Lab (www.shiyanjia.com/paperaward.html) for providing assistance with TEM characterization.

Author information

Authors and Affiliations

Electronic Materials Research Laboratory, Key Laboratory of the Ministry of Education, School of Electronic Science and Engineering, **’an Jiaotong University, **’an, 710049, People’s Republic of China
Wen**g Shi, Leiyang Zhang, Ruiyi **g, Yunyao Huang, **aoyong Wei & Li **
School of Materials and Energy, Southwest University, Chongqing, 400715, People’s Republic of China
Fukang Chen & Gang Liu
School of Natural Sciences and Mathematics, Ural Federal University, Ekaterinburg, 620000, Russia
Vladimir Shur
Multifunctional Electronic Ceramics Laboratory, College of Engineering, **’an International University, **’an, 710077, People’s Republic of China
Hongliang Du

Authors

Wen**g Shi
View author publications
You can also search for this author in PubMed Google Scholar
Leiyang Zhang
View author publications
You can also search for this author in PubMed Google Scholar
Ruiyi **g
View author publications
You can also search for this author in PubMed Google Scholar
Yunyao Huang
View author publications
You can also search for this author in PubMed Google Scholar
Fukang Chen
View author publications
You can also search for this author in PubMed Google Scholar
Vladimir Shur
View author publications
You can also search for this author in PubMed Google Scholar
**aoyong Wei
View author publications
You can also search for this author in PubMed Google Scholar
Gang Liu
View author publications
You can also search for this author in PubMed Google Scholar
Hongliang Du
View author publications
You can also search for this author in PubMed Google Scholar
Li **
View author publications
You can also search for this author in PubMed Google Scholar

Corresponding authors

Correspondence to Gang Liu, Hongliang Du or Li **.

Ethics declarations

Conflict of interest

The authors declare no interest conflict. They have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.

Supplementary Information

Below is the link to the electronic supplementary material.

Supplementary file1 (PDF 1034 kb)

Rights and permissions

Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.

Reprints and permissions

About this article

Cite this article

Shi, W., Zhang, L., **g, R. et al. Moderate Fields, Maximum Potential: Achieving High Records with Temperature-Stable Energy Storage in Lead-Free BNT-Based Ceramics. Nano-Micro Lett. 16, 91 (2024). https://doi.org/10.1007/s40820-023-01290-4

Download citation

Received: 30 June 2023
Accepted: 16 November 2023
Published: 18 January 2024
DOI: https://doi.org/10.1007/s40820-023-01290-4

Keywords

Use our pre-submission checklist

Avoid common mistakes on your manuscript.

Moderate Fields, Maximum Potential: Achieving High Records with Temperature-Stable Energy Storage in Lead-Free BNT-Based Ceramics

Highlights

Abstract

Similar content being viewed by others

High energy storage properties of Nd(Mg2/3Nb1/3)O3 modified Bi0.5Na0.5TiO3 lead-free ceramics

Broad-high operating temperature range and enhanced energy storage performances in lead-free ferroelectrics

Bi0.5Na0.5TiO3-based ceramics with high energy storage density and good thermal stability

1 Introduction

2 Experimental Section

2.1 Sample Preparation

2.2 Structural Characterization

2.3 Dielectric, Ferroelectric, and ES Properties Measurement

3 Results and Discussion

3.1 XRD Structural Characterization

3.2 Dielectric Properties

3.3 Surface Microstructures

3.4 Nanoscale Microstructures

3.5 Ferroelectric and ES Performance

3.6 Charge–Discharge Performance

4 Conclusions

References

Acknowledgements

Author information

Authors and Affiliations

Corresponding authors

Ethics declarations

Conflict of interest

Supplementary Information

Supplementary file1 (PDF 1034 kb)

Rights and permissions

About this article

Cite this article

Keywords

Navigation

Moderate Fields, Maximum Potential: Achieving High Records with Temperature-Stable Energy Storage in Lead-Free BNT-Based Ceramics

Highlights

Abstract

Similar content being viewed by others

High energy storage properties of Nd(Mg2/3Nb1/3)O3 modified Bi0.5Na0.5TiO3 lead-free ceramics

Broad-high operating temperature range and enhanced energy storage performances in lead-free ferroelectrics

Bi0.5Na0.5TiO3-based ceramics with high energy storage density and good thermal stability

1 Introduction

2 Experimental Section

2.1 Sample Preparation

2.2 Structural Characterization

2.3 Dielectric, Ferroelectric, and ES Properties Measurement

3 Results and Discussion

3.1 XRD Structural Characterization

3.2 Dielectric Properties

3.3 Surface Microstructures

3.4 Nanoscale Microstructures

3.5 Ferroelectric and ES Performance

3.6 Charge–Discharge Performance

4 Conclusions

References

Acknowledgements

Author information

Authors and Affiliations

Corresponding authors

Ethics declarations

Conflict of interest

Supplementary Information

Supplementary file1 (PDF 1034 kb)

Rights and permissions

About this article

Cite this article

Share this article

Keywords

Search

Navigation