Niobate-based lead-free dielectric energy storage ceramic material as well as preparation method and application thereof

Abstract

The invention belongs to the technical field of ceramic materials, and particularly relates to a niobate-based lead-free dielectric energy storage ceramic material as well as a preparation method and application thereof. The chemical formula of the dielectric energy storage ceramic material is (NaNbO3) (1-x) [(Ba1 / 3Ca1 / 3Sr1 / 3) (Zr1 / 2Ti1 / 2) O3] x, and x is larger than or equal to 0.01 and smaller than or equal to 0.2. An entropy modulation component is introduced into a niobate system, a nano polar island is constructed, and reversible quick response of the ceramic material to an electric field is achieved. The electrical microstructure of the sodium niobate ceramic is optimized, so that the relaxation time distribution of the material is normalized, and a structural basis is provided for excellent electrical properties. High energy storage performance is achieved in a wide temperature range, the energy storage density is 12 J cm <-3 >, and the energy storage efficiency is 95%.

Description

Technical Field

[0001] This invention belongs to the field of ceramic materials technology, and specifically relates to a niobate-based lead-free dielectric energy storage ceramic material, its preparation method, and its application. Background Technology

[0002] With the development of high power density in electrical and electronic applications such as electric vehicles, pulsed lasers, consumer electronics, aerospace, and smart grids, dielectric ceramic capacitors have become key energy storage components due to their nanosecond-level charge and discharge rates. Currently, mainstream lead-containing materials, such as lead lanthanum zirconate titanate ceramics (PLZT), face environmental regulatory restrictions, while lead-free alternatives (such as BaTiO3 or Na) are becoming increasingly important. 0.5 Bi 0.5 TiO3-based materials generally have high energy density (W). rec The problem of balancing efficiency (η) and remanent polarization in ferroelectrics: W rec Low efficiency and hysteresis in antiferroelectric phase transitions limit the improvement of η. Furthermore, performance degradation at high temperatures (>150℃) and in wide frequency ranges further restricts its application.

[0003] Entropy engineering introduces configurational entropy effects through multi-ion doping of crystals, which can stabilize the lattice of materials such as bismuth layered dielectrics and improve energy storage performance. However, its ambiguity in electrical microstructure and uncontrollable carrier transport lead to a decrease in breakdown field strength (E0). b Optimization is limited. Relaxor ferroelectrics utilize polar nanodomains (PNRs) to replace traditional ferroelectric domains, aiming to synergistically enhance W. rec The presence of η provides possibilities. Although the dynamics of PNRs have been studied in systems such as BaTiO3, the lack of atomic-scale mechanistic analysis in entropy-modified materials hinders the targeted regulation of performance.

[0004] While impedance spectroscopy (IS) can resolve the electrical microstructure of materials, current research focuses on mature materials. In most novel dielectric materials, the imaginary part of the dielectric modulus (M″) and the imaginary part of the impedance (Z″) spectrum exhibit single-peak overlap, making it impossible to distinguish grain / grain boundary responses. Although NaNbO3 (NN)-based materials possess antiferroelectric-ferroelectric phase transition characteristics similar to PLZT, the lack of resolution of their electrical microstructure has resulted in a lack of theoretical guidance for composition optimization, hindering their E... b It lags significantly behind lead-based systems in terms of η.

[0005] In summary, existing entropy-modified NN-based materials have three major drawbacks: First, the electrical microstructure is indistinguishable, hindering E... b First, the synergistic effect with η is problematic. Second, the dynamic mechanism of PNRs in NN-based materials is unclear. Third, component design relies on trial and error, making it difficult to establish a quantitative control path for "structure-performance". Developing entropy modulation strategies that can accurately analyze and optimize electrical microstructures is a key requirement for unlocking the potential of NN-based materials as dielectrics for energy storage capacitors. Summary of the Invention

[0006] In order to overcome at least one of the technical problems existing in the prior art, one of the objectives of the present invention is to provide a dielectric energy storage ceramic material.

[0007] The second objective of this invention is to provide a method for preparing dielectric energy storage ceramic materials.

[0008] The third objective of this invention is to provide a ceramic capacitor.

[0009] The fourth objective of this invention is to provide the application of the above-mentioned dielectric energy storage ceramic material or the above-mentioned ceramic capacitor in the field of electrical and electronic engineering.

[0010] To achieve the above objectives, the technical solution adopted by the present invention is as follows: The first aspect of the present invention provides a dielectric energy storage ceramic material, wherein the chemical formula of the dielectric energy storage ceramic material is (NaNbO3). (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x , where 0.01≤ x ≤0.2.

[0011] The chemical formula of the dielectric energy storage ceramic material in this invention was determined by XRD data and the amount of raw materials used.

[0012] In some embodiments of the present invention, 0.1 ≤ x ≤0.16.

[0013] In some embodiments of the present invention x The range of values ​​is any one of 0.01, 0.02, 0.03, 0.04, 0.05, 0.06, 0.07, 0.08, 0.09, 0.1, 0.11, 0.12, 0.13, 0.14, 0.15, 0.16, 0.17, 0.18, 0.19, 0.2, or any combination thereof; in some embodiments of the present invention, x The values ​​are 0.1, 0.13, or 0.16.

[0014] The second aspect of the present invention provides a method for preparing the dielectric energy storage ceramic material described in the first aspect of the present invention, comprising the following steps: Sodium source, niobium source, barium source, calcium source, strontium source, titanium source and zirconium source are ground and mixed, and then pre-calcined to obtain pre-calcined powder; The pre-fired powder is mixed with a binder and then pressed into shape to obtain a ceramic green body; The ceramic green body is debinded and then sintered to obtain the dielectric energy storage ceramic material.

[0015] In some embodiments of the present invention, the sodium source includes at least one of Na2CO3 and Na(HCO3)2.

[0016] In some embodiments of the present invention, the niobium source includes at least one of Nb2O5, NbO, Nb2O2, NbO2, and Nb2O3.

[0017] In some embodiments of the present invention, the barium source includes at least one of BaO and BaCO3.

[0018] In some embodiments of the present invention, the calcium source includes at least one of CaO, CaCO3, and Ca(HCO3)2.

[0019] In some embodiments of the present invention, the strontium source includes at least one of SrO, SrCO3, and Sr(HCO3)2.

[0020] In some embodiments of the present invention, the titanium source includes TiO2.

[0021] In some embodiments of the present invention, the zirconium source includes ZrO2.

[0022] In some embodiments of the present invention, the pre-calcination temperature is 800~1000℃; in some embodiments of the present invention, the pre-calcination temperature is any value of 800℃, 850℃, 900℃, 950℃, 1000℃ or a range formed by any two of them.

[0023] In some embodiments of the present invention, the pre-calcination time is 2 to 4 hours; in some embodiments of the present invention, the pre-calcination time is any value of 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, or a range formed by any two of them.

[0024] In some embodiments of the present invention, the heating rate of the pre-calcination is 3~6℃ / min; in some embodiments of the present invention, the heating rate of the pre-calcination is any value of 3℃ / min, 3.5℃ / min, 4℃ / min, 4.5℃ / min, 5℃ / min, 5.5℃ / min, 6℃ / min or a range formed by any two of these values.

[0025] In some embodiments of the present invention, the sintering temperature is 800~1500℃; in some embodiments of the present invention, the sintering temperature is any value of 800℃, 850℃, 900℃, 950℃, 1000℃, 1100℃, 1200℃, 1300℃, 1400℃, 1500℃ or a range formed by any two of them.

[0026] In some embodiments of the present invention, the sintering time is 2 to 4 hours; in some embodiments of the present invention, the sintering time is any value of 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, or a range formed by any two of them.

[0027] In some embodiments of the present invention, the heating rate of the sintering is 3~6℃ / min; in some embodiments of the present invention, the heating rate of the sintering is any value of 3℃ / min, 3.5℃ / min, 4℃ / min, 4.5℃ / min, 5℃ / min, 5.5℃ / min, 6℃ / min or a range formed by any two of these values.

[0028] In some embodiments of the present invention, the temperature for discharging adhesive is 550~650℃; in some embodiments of the present invention, the temperature for discharging adhesive is any value or a range formed by any two of 550℃, 560℃, 570℃, 580℃, 590℃, 600℃, 610℃, 620℃, 630℃, 640℃, and 650℃.

[0029] In some embodiments of the present invention, the glue removal time is 2 to 3 hours; in some embodiments of the present invention, the glue removal time is any value of 2 hours, 2.2 hours, 2.4 hours, 2.5 hours, 2.6 hours, 2.8 hours, 3 hours, or a range formed by any two of these values.

[0030] In some embodiments of the present invention, the heating rate of the adhesive removal is 1~10℃ / min; in some embodiments of the present invention, the heating rate of the adhesive removal is any value or a range formed by any two of 1℃ / min, 2℃ / min, 3℃ / min, 4℃ / min, 5℃ / min, 6℃ / min, 7℃ / min, 8℃ / min, 9℃ / min, and 10℃ / min.

[0031] In some embodiments of the present invention, the pressure during compression molding is 130~200MPa; in some embodiments of the present invention, the pressure during compression molding is any value of 130MPa, 140MPa, 150MPa, 160MPa, 170MPa, 180MPa, 190MPa, 200MPa or a range formed by any two of them.

[0032] In some embodiments of the present invention, the mass of the binder is 0.1 to 0.5% of the mass of the pre-fired powder; in some embodiments of the present invention, the mass of the binder is any one of 0.1%, 0.2%, 0.3%, 0.4%, 0.5% of the mass of the pre-fired powder, or a range formed by any two of these values.

[0033] In some embodiments of the present invention, the adhesive is selected from at least one of polyvinyl alcohol, polyvinyl butyral, carboxymethyl cellulose, polyacrylic acid, and polyvinylidene fluoride.

[0034] In some embodiments of the present invention, the grinding and mixing process uses alcohols as solvents; the mass ratio of solvent, grinding balls and raw materials is (2~2.5):(1.5~2):1.

[0035] In some embodiments of the present invention, the pre-calcined powder needs to be ground, dried and sieved before being mixed with the binder.

[0036] In some embodiments of the present invention, the sieving process refers to passing the dried powder through a 100-150 mesh sieve.

[0037] In some embodiments of the present invention, the drying temperature is 80~100°C.

[0038] In some embodiments of the present invention, the pre-calcined powder and the binder are mixed by ball milling.

[0039] In some embodiments of the present invention, the mass ratio of the binder, grinding balls and pre-fired powder is (2~2.5):(1.5~2):1.

[0040] In some embodiments of the present invention, the grinding ball is a zirconia grinding ball.

[0041] In some embodiments of the present invention, the grinding time is 22-28 hours.

[0042] In some embodiments of the present invention, the grinding speed is 100~1000 r / min.

[0043] A third aspect of the present invention provides a ceramic capacitor comprising the dielectric energy storage ceramic material described in the first aspect of the present invention.

[0044] The fourth aspect of the present invention provides the application of the dielectric energy storage ceramic material described in the first aspect of the present invention or the ceramic capacitor provided in the third aspect of the present invention in the field of electrical and electronic engineering.

[0045] In some embodiments of the present invention, the electrical and electronic fields include electric vehicles, pulsed lasers, consumer electronics, aerospace, or smart grids.

[0046] The beneficial effects of this invention are: by introducing (Ba) into niobate-based ceramic materials... 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 The entropy regulating component (NaNbO3) was used to construct a system based on (NaNbO3). (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x This invention relates to a perovskite-structured dielectric energy storage ceramic. By employing entropy modulation, the resolvable electrical microstructure is optimized, resulting in a ceramic material with high energy storage performance. Furthermore, the dielectric energy storage ceramic material of this invention can synergistically regulate lattice distortion and configurational entropy, inducing uniformly distributed sub-nanometer polar microregions (PNRs), and significantly normalizing the relaxation time in the electrical microstructure, achieving high energy storage performance. It also exhibits high discharge current and energy stability within a temperature range of 25–150 °C, demonstrating significant application value.

[0047] This invention constructs nano-polar islands by introducing entropy modulation components into the niobate system, achieving a reversible and rapid response of the ceramic material to an electric field. The electrical microstructure of the sodium niobate ceramic was optimized, normalizing the relaxation time distribution and providing a structural basis for excellent electrical performance. High energy storage performance was achieved over a wide temperature range, with an energy storage density of 12 J / cm³. -3 The energy storage efficiency is 95%.

[0048] The preparation method in this invention is simple, highly controllable, and uses common raw materials and reagents. It does not contain toxic elements such as lead and has broad application prospects. Attached Figure Description

[0049] Figure 1 The images show the XRD patterns of the ceramic materials in Examples 1-3 and Comparative Example 1.

[0050] Figure 2 The diagram shows the configurational entropy test results of the ceramic materials in Examples 1-3 and Comparative Example 1.

[0051] Figure 3 The diagram shows the unipolar hysteresis loop test results of the ceramic materials in Examples 1-3 and Comparative Example 1.

[0052] Figure 4The images are scanning electron microscope images of the ceramic materials in Examples 1-3 and Comparative Example 1.

[0053] Figure 5 The dielectric constant temperature spectrum of the ceramic materials in Examples 1-3 and Comparative Example 1 is shown.

[0054] Figure 6 The dielectric loss temperature spectra of the ceramic materials in Examples 1-3 and Comparative Example 1 are shown.

[0055] Figure 7 The spectrum diagrams show the imaginary part of impedance and the imaginary part of electrokinetic modulus of the ceramic materials in Examples 1-3 and Comparative Example 1. Detailed Implementation

[0056] The specific implementation of the present invention will be further described in detail below with reference to the accompanying drawings and examples, but the implementation and protection of the present invention are not limited thereto. It should be noted that any processes not specifically described in detail below are those that can be implemented or understood by those skilled in the art by referring to the prior art. Reagents or instruments used without specified manufacturers are all conventional products that can be purchased commercially.

[0057] The polyvinyl alcohol (PVA) used in the following examples and comparative examples was purchased from Aladdin Reagents.

[0058] Example 1 This example provides a niobate-based lead-free dielectric energy storage ceramic material with the chemical formula: (NaNbO3). (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x ,in x =0.10.

[0059] The niobate-based lead-free dielectric energy storage ceramic material in this example was prepared using a method including the following steps: 1. Select Na2CO3, Nb2O5, BaCO3, CaCO3, SrCO3, TiO2, and ZrO2 as raw materials. The amount of each substance used is determined by the proportion of metal elements in the chemical formula of the product. 2. According to the metallic elements in (NaNbO3) (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x (in xThe weight ratio of the raw materials was calculated using the molar stoichiometric ratio in (=0.10). The raw material powder was weighed and mixed. The mixed powder was then ball-milled once using isopropanol and ZrO2 balls as the ball milling media in a polytetrafluoroethylene tank. The mass ratio of isopropanol, ZrO2 balls and mixed powder was 2:2:1. The ball milling speed was 300 r / min and the ball milling time was 24 h. After that, it was dried to obtain a precursor mixed powder with uniform particle size distribution. 3. Calcine the powder after ball milling in step 2 to obtain pre-calcined powder. The pre-calcination temperature is 900℃ and the time is 3h. 4. The pre-calcined powder from step 3 is ball-milled using isopropanol and ZrO2 balls as the ball-milling media in a polytetrafluoroethylene jar. The mass ratio of isopropanol, ZrO2 balls to powder is 2:2:1. The ball-milling speed is 300 r / min and the ball-milling time is 24 h. After that, it is dried at 90℃ and passed through a 120-mesh sieve to obtain an intermediate powder with uniform particle size distribution after secondary ball milling. 5. Add 0.5 wt% PVA aqueous solution to the powder, grind and granulate in a mortar to obtain a powder with good flowability and dispersibility. 6. Place the powder obtained in step 5 into a mold and press it into a sheet at a pressure of 200 MPa to obtain a ceramic green body; 7. Place the ceramic green body obtained in step 6 into a muffle furnace for debinding treatment at a temperature of 550℃, a heating rate of 3℃ / min, and a time of 2h. 8. The green body obtained in step 7 after debinding is sintered at a heating rate of 5℃ / min, a sintering temperature of 1300℃, and a sintering time of 2h in air to obtain the niobate-based lead-free dielectric energy storage ceramic material in this example.

[0060] Example 2 This example provides a niobate-based lead-free dielectric energy storage ceramic material with the chemical formula: (NaNbO3). (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x ,in x =0.13.

[0061] The niobate-based lead-free dielectric energy storage ceramic material in this example can be prepared by referring to the preparation method in Example 1.

[0062] Example 3 This example provides a niobate-based lead-free dielectric energy storage ceramic material with the chemical formula: (NaNbO3). (1-x) [(Ba 1 / 3 Ca1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x ,in x =0.16.

[0063] The niobate-based lead-free dielectric energy storage ceramic material in this example can be prepared by referring to the preparation method in Example 1.

[0064] Comparative Example 1 This example provides a niobate-based lead-free dielectric energy storage ceramic material with the chemical formula: (NaNbO3). (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x ,in x =0.

[0065] The niobate-based lead-free dielectric energy storage ceramic material in this example can be prepared by referring to the preparation method in Example 1.

[0066] Performance testing: The X-ray diffraction patterns of the niobate-based lead-free dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 were measured using an X-ray diffractometer. Specific test results are as follows: Figure 1 As shown. By Figure 1 It can be seen that the niobate-based lead-free dielectric energy storage ceramic materials in Comparative Example 1 and Examples 1-3 are all stable perovskite phases without obvious two phases. In addition, three small peaks appeared between 35° and 45°, indicating the presence of a superlattice structure in the ceramic.

[0067] The configurational entropy of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 is calculated using the following formulas:

[0068] in R It is the ideal gas constant; N and M These represent the total number of ion types at the cation and anion sites, respectively. x i and x j They are the first i and the j The mole fraction of each ion among all cations / anions is calculated as follows: Figure 2 As shown. By Figure 2 It can be seen that, with xAs the value increases, the configuration entropy also increases, eventually reaching the medium entropy range from low entropy.

[0069] The unipolar hysteresis loops of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 were tested respectively, and the specific test results are as follows: Figure 3 As shown, Figure 3 The data were obtained by testing samples coated with upper and lower electrodes using the Radiant Precision Multiferroic II ferroelectric material testing system from the United States. These samples were prepared by grinding the niobate-based dielectric energy storage ceramic materials from Examples 1-3 and Comparative Example 1 to approximately 0.2 mm, and then coating their upper and lower surfaces with silver metal electrodes. Figure 3 It can be seen that, with (Ba) 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 Increased O3 doping enhances the relaxation properties of ceramic materials. According to... Figure 3 The test results show the energy storage performance of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1, as detailed in Table 1 below.

[0070] Table 1 Energy storage performance of niobate-based dielectric energy storage ceramic materials

[0071] As shown in Table 1, compared with Comparative Example 1, Embodiments 1-3 of the present invention introduce (Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2Ti 1 / 2 O3 can significantly improve the maximum breakdown field strength (E). max Total energy storage density (W) total ), recyclable energy storage density (W) rec ) and energy storage efficiency (η), and as (Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 As the O3 doping concentration increases, E max W total W rec Both the η and η values ​​increase accordingly.

[0072] Scanning electron microscopy (SEM) images of the surface of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 were obtained. Specific test results are shown below. Figure 4 As shown. By Figure 4 It can be seen that, with (Ba)1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2Ti 1 / 2 As the O3 doping amount increases, the grain size on the surface of the ceramic material gradually decreases.

[0073] The dielectric constant temperature spectra of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 were tested respectively. The specific test results are as follows: Figure 5 As shown, Figure 5 The four small figures a, b, c, and d in the figure are the dielectric constant temperature spectra of Comparative Example 1, Example 1, Example 2, and Example 3, respectively. Figure 5 The data were obtained by measuring samples with electrodes on both the upper and lower surfaces using a Keysight 4294A impedance analyzer. The samples were placed in a temperature-controlled stage. The instrument's V+ and I+ terminals were connected to the upper electrode of the sample via wires and probes, and the instrument's V- and I- terminals were connected to the lower electrode of the sample via wires and probes. The test frequencies were selected as 1 kHz, 10 kHz, and 100 kHz. Before testing, the instrument underwent open-circuit calibration and was held at the test temperature for 5 minutes to ensure system stability. The electrode-coated samples were prepared by grinding the niobate-based dielectric energy storage ceramic materials from Examples 1-3 and Comparative Example 1 to 0.05 mm, and then coating their upper and lower surfaces with silver metal electrodes. Figure 5 It can be seen that the phase transition temperature corresponding to the maximum dielectric constant increases with (Ba) 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 The O3 doping level decreases as the doping concentration increases, until it drops below room temperature.

[0074] The dielectric loss temperature spectra of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 were tested respectively. The specific test results are as follows: Figure 6 As shown in the figure, the data in this graph was obtained by measuring samples with electrodes on both the upper and lower surfaces using a Keysight 4294A impedance analyzer. The samples were placed in a temperature-controlled stage. The instrument's V+ and I+ terminals were connected to the upper electrode of the sample via wires and probes, and the instrument's V- and I- terminals were connected to the lower electrode of the sample via wires and probes. The test frequencies were selected as 1 kHz, 10 kHz, and 100 kHz. Before testing, the instrument underwent open-circuit calibration and was held at the test temperature for 5 minutes to ensure system stability. The samples with electrodes were prepared by grinding the niobate-based dielectric energy storage ceramic materials from Examples 1-3 and Comparative Example 1 to 0.05 mm, and then coating their upper and lower surfaces with silver metal electrodes. Figure 6It can be seen that within the temperature range of 25℃ to 250℃, the dielectric loss of each embodiment is less than 0.02, which meets general application requirements. Among them, the dielectric loss of Embodiment 1 above 200℃ is less than that of Embodiments 2 and 3. At 250℃, the dielectric loss value of Embodiment 1 is 0.006, the dielectric loss value of Embodiment 2 is 0.011, and the dielectric loss value of Embodiment 3 is 0.012.

[0075] The imaginary parts of impedance and electrokinetic modulus of the niobate-based dielectric energy storage ceramic materials in Examples 1-3 and Comparative Example 1 were tested respectively. The specific test results are as follows: Figure 7 As shown, Figure 7 The four smaller figures a, b, c, and d in the figure are the spectrum diagrams of the imaginary part of the impedance and the imaginary part of the electrodynamic modulus for Comparative Example 1, Example 1, Example 2, and Example 3, respectively. Figure 7 The data were obtained by measuring samples with electrodes on both the upper and lower surfaces using a Keysight 4294A impedance analyzer. The samples were placed in a temperature-controlled hot stage. The instrument's V+ and I+ terminals were connected to the upper electrode of the sample via wires and probes, and the instrument's V- and I- terminals were connected to the lower electrode of the sample via wires and probes. The test frequencies were selected as 1 kHz, 10 kHz, and 100 kHz. Before testing, the instrument underwent open-circuit calibration and was held at the test temperature (550 °C) for 5 minutes to ensure system stability. The electrode-coated samples were prepared by grinding the niobate-based dielectric energy storage ceramic materials from Examples 1-3 and Comparative Example 1 to 0.5 mm, and then coating their upper and lower surfaces with silver metal electrodes. Figure 7 It can be seen that, following (Ba) 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 As the O3 doping amount increases, the intensity of the high-frequency impedance peak weakens relative to the low-frequency impedance peak, and the high-frequency electrokinetic modulus peak also shifts to the low frequency, which represents the homogenization of the electrical microstructure.

[0076] In summary, this invention introduces (Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 O3 significantly alters the configurational entropy of ceramic materials, thereby greatly affecting their dielectric energy storage characteristics, giving them both excellent energy storage properties and high reliability.

[0077] The embodiments of the present invention have been described in detail above. However, the present invention is not limited to the above embodiments. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the present invention. Furthermore, the embodiments of the present invention and the features thereof can be combined with each other unless otherwise specified.

Claims

1. A dielectric energy storage ceramic material, characterized in that: The chemical formula of the dielectric energy storage ceramic material is (NaNbO3). (1-x) [(Ba 1 / 3 Ca 1 / 3 Sr 1 / 3 (Zr) 1 / 2 Ti 1 / 2 )O3] x , where 0.01≤ x ≤0.

2.

2. The dielectric energy storage ceramic material according to claim 1, characterized in that: 0.1≤ x ≤0.16。 3. The dielectric energy storage ceramic material according to claim 1, characterized in that: x The values ​​are 0.1, 0.13, or 0.

16.

4. The method for preparing the dielectric energy storage ceramic material according to any one of claims 1 to 3, characterized in that: Includes the following steps: Sodium source, niobium source, barium source, calcium source, strontium source, titanium source and zirconium source are ground and mixed, and then pre-calcined to obtain pre-calcined powder; The pre-fired powder is mixed with a binder and then pressed into shape to obtain a ceramic green body; The ceramic green body is debinded and then sintered to obtain the dielectric energy storage ceramic material.

5. The method for preparing the dielectric energy storage ceramic material according to claim 4, characterized in that: The temperatures for pre-calcination and sintering are 800~1500℃, respectively; And / or, the pre-calcination and sintering times are 2-4 hours respectively; And / or, the heating rates for the pre-calcination and the sintering are 3~6℃ / min, respectively.

6. The method for preparing the dielectric energy storage ceramic material according to claim 4, characterized in that: The glue removal has at least one of the following characteristics: (a1) The temperature for discharging the adhesive is 550~650℃; (a2) The time for degreasing is 2-3 hours; (a3) The heating rate of the glue removal process is 1~10℃ / min.

7. The method for preparing the dielectric energy storage ceramic material according to claim 4, characterized in that: The pressure during the pressing process is 130~200MPa.

8. The method for preparing dielectric energy storage ceramic material according to claim 4, characterized in that: The mass of the binder is 0.1 to 0.5% of the mass of the pre-fired powder.

9. A ceramic capacitor, characterized in that: Includes the dielectric energy storage ceramic material as described in any one of claims 1 to 3.

10. The application of the dielectric energy storage ceramic material according to any one of claims 1 to 3 or the ceramic capacitor according to claim 9 in the field of electrical and electronic engineering.

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