Anti-reduction two-phase anti-ferroelectric energy storage ceramic, preparation method and application thereof

Abstract

The application relates to the technical field of ceramics, in particular to an anti-reduction two-phase anti-ferroelectric energy storage ceramic as well as a preparation method and application thereof. The structure general formula of the ceramic is Pb a La b Zr c Ti d O e +xwt%Y2O3, wherein a=0.5-1.5, b=0.01-0.1, c=0.5-1.5, d=0.005-0.05, e=1.6-4.7; 0<x<8. By adding Y2O3 with a specific content, the stability of the anti-ferroelectric phase of the ceramic is improved, the dispersion relaxation of the ceramic material is promoted, the breakdown electric field of the anti-ferroelectric ceramic is improved, and the anti-reduction performance of the ceramic is also improved; in combination with a specific flow casting process, the prepared ceramic has an energy storage density of 10-12 J / cm 3 , an energy storage efficiency of >80%, and can be used in energy storage capacitors and has a good application prospect in pulse power systems.

Description

Technical Field

[0001] This invention relates to the field of ceramic technology, specifically to a reduction-resistant two-phase antiferroelectric energy storage ceramic, its preparation method, and its application. Background Technology

[0002] With the rapid development of new energy vehicles, 5G communication, and high-power pulse technology, the application demand for high-voltage, high-power multilayer ceramic capacitors (MLCCs) is increasingly strong. Energy storage ceramic materials, as their core dielectric, have become a key direction for technological research and development. Antiferroelectric ceramics, due to their high current throughput during electric field-induced phase transitions, exhibit significant advantages in high-voltage, high-power scenarios. Among them, lead-based ceramics such as PLZT (lead-lanthanum-zirconium-titanium) and PLZST (lead-lanthanum-zirconium-strontium-titanium) have become mainstream research objects due to their excellent dielectric and ferroelectric properties. However, existing energy storage ceramics still face many technical bottlenecks. On the one hand, their resistance to reduction is insufficient, easily leading to problems such as oxygen vacancies and metallic lead precipitation, which damage the crystal structure and cause electrical performance degradation, making it difficult to adapt to the co-firing requirements of low-cost base metal (Ni, Cu) internal electrodes. On the other hand, their high-temperature stability is limited. Most ceramics exhibit dielectric constant fluctuations, decreased breakdown strength, and increased dielectric loss in environments above 150℃ due to enhanced domain wall movement and intensified defect migration, failing to meet the requirements of extreme operating conditions. In addition, the traditional solid-state preparation process has the problem of high sintering temperature (usually >1300℃), which can easily lead to abnormal grain growth and increased porosity, further affecting the energy storage efficiency and reliability of the material.

[0003] Chinese invention patent application CN115947598A discloses an antiferroelectric material that can be co-fired with a base metal internal electrode and its preparation method. It lowers the sintering temperature of PLZST-based ceramics to 960℃ by adding glass additives, while maintaining a sintering temperature of 2.52 J / cm² under a low-oxygen atmosphere. 3 The energy storage density and 80% energy storage efficiency achieved preliminary adaptation for base metal co-firing. However, this patent uses a single tetragonal phase structure design, resulting in a maximum energy storage density of only 3.72 J / cm³. 3 Furthermore, the reduction resistance depends on the physical barrier of the glass phase, and the deep synergy between reduction resistance and high energy storage has not been achieved from the intrinsic structure of the material. The stability over a wide temperature range has also not been effectively optimized. Summary of the Invention

[0004] The first aspect of this invention provides a reduction-resistant two-phase antiferroelectric energy storage ceramic, the general structural formula of which is: Pb a La b Zr c Ti d O e+xwt% Y2O3, where a = 0.5 - 1.5, b = 0.01 - 0.1, c = 0.5 - 1.5, d = 0.005 - 0.05, e = 1.6 - 4.7; 0 < x < 8.

[0005] Optionally, the value range of x is: 2 ≤ x ≤ 6.

[0006] Optionally, the value range of x is: 3 ≤ x ≤ 5.

[0007] The present invention defines the general structural formula of the ceramic as: Pb a La b Zr c Ti d O e +xwt% Y2O3, and a = 0.5 - 1.5, b = 0.01 - 0.1, c = 0.5 - 1.5, d = 0.005 - 0.05, e = 1.6 - 4.7; 0 < x < 8. By adding a specific content of Y2O3, not only the stability of the antiferroelectric phase of the ceramic is improved, the diffusional relaxation of the ceramic material is promoted, the breakdown electric field of the antiferroelectric ceramic is increased, but also the anti-reduction performance of the ceramic is enhanced. It may be that Y2O3 has a synergistic effect with the main perovskite structure: after Y2O3 is added in the initial mixing stage of the ingredients, through the secondary pre-sintering and sintering process in a reducing atmosphere, it reacts with the Zr element in the main phase to form a second-phase yttrium zirconate with a highly disordered defective fluorite structure. This second phase forms a stable two-phase coexistence system with the main perovskite structure. On the one hand, the highly disordered vacancies in the fluorite structure will induce the diffusional relaxation transition of the main antiferroelectric body, inhibit the violent movement of domain walls, shift the antiferroelectric-ferroelectric phase transition towards a higher electric field direction, significantly enhance the thermodynamic stability of the antiferroelectric phase, and reduce the energy loss during the phase transition process; on the other hand, the second-phase particles are uniformly dispersed in the main-phase matrix, which can effectively hinder the abnormal growth of grains, achieve grain refinement, and at the same time fill the micro-pores generated during the sintering process of the main phase, greatly improve the densification degree of the ceramic, reduce the charge transport channels such as oxygen vacancies and grain boundary defects, and thus significantly increase the breakdown electric field of the ceramic; in addition, as a highly stable oxide, the second phase formed by Y2O3 can build a physical barrier in a reducing atmosphere, inhibit the reduction precipitation of the Pb element in the main phase and the excessive generation of oxygen vacancies, protect the integrity of the perovskite lattice structure, and intrinsically enhance the anti-reduction performance of the ceramic. Within the defined element ratio range, this synergistic mechanism of main-phase relaxation regulation - second-phase structure reinforcement - anti-reduction barrier construction finally realizes the synchronous optimization of the stability of the antiferroelectric phase, breakdown electric field, and anti-reduction performance of the ceramic, ensuring that the material still has a high energy storage density of 10 - 12 J / cm 3 and a high energy storage efficiency of > 80% after sintering in a reducing atmosphere.

[0008] The values ​​are a = 0.8~1.2, b = 0.02~0.07, c = 0.8~1.2, d = 0.008~0.02, and e = 2.5~3.5.

[0009] The raw materials for preparing the ceramic include: Pb3O4, La2O3, ZrO2, TiO2 and Y2O3.

[0010] The raw materials for preparing the ceramic also include solvents and additives, wherein the additives include at least one of dispersants, binders, plasticizers, and homogenizers.

[0011] The solvent includes at least one of toluene, anhydrous ethanol, acetone, ethyl acetate, cyclohexane, ethylene glycol ethyl ether, and N,N-dimethylformamide.

[0012] The plasticizer includes at least one of polyethylene glycol, dibutyl phthalate, dioctyl phthalate, tributyl citrate, dioctyl adipate, epoxidized soybean oil, and dibutyl sebacate.

[0013] The dispersant includes at least one of tributyl phosphate, polycarboxylate ammonium salt, Span 80, Tween 80, sodium hexametaphosphate, and triethanolamine.

[0014] The adhesive includes at least one of polyvinyl butyral resin, polyvinyl alcohol, polymethyl methacrylate, epoxy resin, sodium carboxymethyl cellulose, and polyvinyl acetate.

[0015] The homogenizer includes at least one of cyclohexanone, isophorone, diacetone alcohol, propylene glycol methyl ether acetate, acetylacetone, and methyl isobutyl ketone.

[0016] Optionally, the solvent includes toluene and anhydrous ethanol, wherein the mass ratio of toluene to anhydrous ethanol is (1~4):1.

[0017] Optionally, the plasticizer includes polyethylene glycol and dibutyl phthalate; the mass ratio of polyethylene glycol to dibutyl phthalate is (1~2):1.

[0018] Optionally, the dispersant includes tributyl phosphate.

[0019] Optionally, the adhesive may include polyvinyl butyral resin.

[0020] Optionally, the homogenizer includes cyclohexanone.

[0021] A second aspect of the present invention provides a method for preparing ceramics, comprising the following steps:

[0022] Step 1: Prepare Pb3O4, La2O3, ZrO2, TiO2, and Y2O3 according to the stoichiometric ratio of the general formula for ceramic structure;

[0023] Step 2: Pb3O4, La2O3, ZrO2, TiO2 and Y2O3 are ball-milled and mixed evenly, dried, pre-sintered and then ball-milled again to obtain powder;

[0024] Step 3: The powder is ball-milled and mixed with solvent and additives to form a casting slurry, and a casting film is obtained through casting process. The film is then laminated and pressed to obtain a ceramic green body.

[0025] Step 4: After removing the binder from the ceramic green body, it is sintered in a reducing atmosphere to obtain ceramic.

[0026] The thickness of the cast film is 15-40 μm.

[0027] The pre-sintering treatment employs a two-stage pre-firing process. The temperature of the two-stage pre-firing is 700~900℃, the heating rate is 1~8℃ / min, the cooling rate is 3~15℃ / min, and the holding time is 2~5h.

[0028] Optionally, the temperature of the secondary pre-firing is 800~900℃, the heating rate is 1~4℃ / min, the cooling rate is 8~15℃ / min, and the holding time is 3~4h.

[0029] The temperature for discharging the adhesive is 450℃~700℃, the heating rate is 0.5~3℃ / min, the cooling rate is 3~5℃ / min, and the holding time is 3~5h.

[0030] Optionally, the temperature for discharging the adhesive is 500℃~600℃, the heating rate is 1~3℃ / min, the cooling rate is 3~5℃ / min, and the holding time is 4~5h.

[0031] The reducing atmosphere includes nitrogen and hydrogen, with a nitrogen to hydrogen volume ratio of 200:(0.5~3); the sintering temperature is 1000~1200℃, the heating rate is 3~8℃ / min, the cooling rate is 3~10℃ / min, and the holding time is 3~5h.

[0032] Optionally, the sintering method includes sintering in lead-containing powder.

[0033] Optionally, the volume ratio of nitrogen to hydrogen is 200:(0.5~2); the temperature of the sintering is 1100~1200℃, the heating rate is 3~8℃ / min, the cooling rate is 3~10℃ / min, and the holding time is 3~4h.

[0034] A third aspect of the present invention provides an application of ceramics in the manufacture of dielectric energy storage capacitors.

[0035] Beneficial effects

[0036] 1. The structural general formula of the ceramics defined by the present invention is: Pb a La b Zr c Ti d O e +xwt%Y2O3, where a = 0.5 - 1.5, b = 0.01 - 0.1, c = 0.5 - 1.5, d = 0.005 - 0.05, e = 1.6 - 4.7; 0 < x < 8. By adding a specific content of Y2O3, not only the stability of the antiferroelectric phase of the ceramics is improved, the diffuse relaxation of the ceramic material is promoted, the breakdown electric field of the antiferroelectric ceramics is enhanced, but also the anti-reduction performance of the ceramics is improved.

[0037] 2. By defining the value range of x in the structural general formula of the ceramics as: 3 ≤ x ≤ 5, the balance between high energy storage density and high energy storage efficiency of the ceramics can be achieved.

[0038] 3. The present invention adopts a specific secondary pre-sintering and multiple ball-milling processes, which can improve the density of the tape-cast film and also refine the grain size of the ceramics, thereby improving the breakdown electric field of the ceramics.

[0039] 4. The ceramic energy storage density of the ceramics prepared by the present invention in combination with a specific tape-casting process is 10 - 12 J / cm 3 , and the energy storage efficiency > 80%.

[0040] 5. The ceramics prepared by the present invention can be used in energy storage capacitors and have good application prospects in pulsed power systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 XRD curves of the ceramics prepared by the comparative example and the examples.

[0042] Figure 2 SEM curves of the ceramics prepared by the comparative example and the examples and the energy spectrum diagram of the surface of Comparative Example 2 (where PLZT in Comparative Example 2 refers to the phase composed of Pb, La, Zr and Ti; Y refers to the phase region composed of Y).

[0043] Figure 3 Electric hysteresis loops of the ceramics prepared by the comparative example and the examples under the breakdown electric field.

[0044] Figure 4 Energy storage density and energy storage efficiency of the ceramics prepared by the comparative example and the examples. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0045] Example 1

[0046] An anti-reduction two-phase antiferroelectric energy storage ceramic, the structural general formula of the ceramic is: Pb 0.94 La 0.04 Zr 0.99Ti 0.01 The ceramic preparation method, consisting of O3 + 2wt%Y2O3, includes the following steps:

[0047] (1) Powder was prepared in stoichiometric ratio, with the contents of Pb3O4, La2O3, ZrO2 and TiO2 being the same as those in the comparative example, and 2wt% Y2O3 was added based on the mass ratio of the actual prepared powder.

[0048] (2) The powder prepared in step (1) is initially mixed by wet ball milling, dried and ground, compacted in a crucible and pre-fired using a two-stage pre-fired method. The pre-fired heating rate is 3℃ / min, and the temperature is raised to 850℃. Then, the temperature is lowered to 800℃ at a cooling rate of 10℃ / min and kept at that temperature for 3 hours. The temperature is then lowered to room temperature at a cooling rate of 3℃ / min.

[0049] (3) Grind and ball mill the pre-calcined block obtained in step (2), dry and grind it through a 200-mesh sieve to obtain powder. According to the casting slurry formula, prepare the following (by weight): 48% solvent (toluene: anhydrous ethanol = 3:1), 2% dispersant (tributyl phosphate), 4% plasticizer (polyethylene glycol: dibutyl phthalate mass ratio = 1:1, of which polyethylene glycol: Shanghai Chemical Reagent Co., Ltd.), 6% binder (polyvinyl butyral, Sinopharm Chemical Reagent Co., Ltd.), 2% homogenizer (cyclohexanone). Make up the balance of powder, ball mill for 12 hours and then carry out casting process to obtain a 20μm thick casting film.

[0050] (4) Cut and stack the cast film obtained in step (3) to 1 mm, press it through a tablet press and a cold isostatic press to obtain a ceramic green body, and then debind and sinter the ceramic green body in sequence. The debinding temperature is 600℃, the heating rate is 1℃ / min, the cooling rate is 4℃ / min, and the holding time is 5h. The sintering operation will be carried out in a reducing atmosphere (sintering in lead-containing powder). The volume ratio of reducing gas during sintering is 200:1 for nitrogen and 1200℃, the heating rate is 5℃ / min, the cooling rate is 7℃ / min, the holding time is 3h, and the temperature is cooled to room temperature.

[0051] Example 2

[0052] A reduction-resistant two-phase antiferroelectric energy storage ceramic, the general structural formula of which is: Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 The ceramic preparation method, consisting of O3 + 4wt%Y2O3, includes the following steps:

[0053] (1) Powder was prepared in stoichiometric ratio, with the contents of Pb3O4, La2O3, ZrO2 and TiO2 being the same as those in the comparative example, and 4wt% Y2O3 was added based on the actual mass ratio of the prepared powder.

[0054] (2) The powder prepared in step (1) is initially mixed by wet ball milling, dried and ground, compacted in a crucible and pre-fired using a two-stage pre-fired method. The pre-fired heating rate is 3℃ / min, and the temperature is raised to 850℃. Then, the temperature is lowered to 800℃ at a cooling rate of 10℃ / min and kept at that temperature for 3 hours. The temperature is then lowered to room temperature at a cooling rate of 3℃ / min.

[0055] (3) Grind the pre-fired block obtained in step (2) and ball mill it to refine it. Dry and grind it through a 200-mesh sieve to obtain powder. Prepare it according to the casting slurry formula (same as in Example 1). After ball milling for 12 hours, perform casting process to obtain a 20μm thick casting film.

[0056] (4) Cut and stack the cast film obtained in step (3) to 1 mm, press it through a tablet press and a cold isostatic press to obtain a ceramic green body, and then debind and sinter the ceramic green body in sequence. The debinding temperature is 600℃, the heating rate is 1℃ / min, the cooling rate is 4℃ / min, and the holding time is 5h. The sintering operation will be carried out in a reducing atmosphere (sintering in lead-containing powder). The volume ratio of reducing gas during sintering is 200:1 for nitrogen and 1160℃, the heating rate is 5℃ / min, the cooling rate is 7℃ / min, the holding time is 3h, and the temperature is cooled to room temperature.

[0057] Example 3

[0058] A reduction-resistant two-phase antiferroelectric energy storage ceramic, the general structural formula of which is: Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 The ceramic preparation method, consisting of O3 + 6wt%Y2O3, includes the following steps:

[0059] (1) Powder was prepared in stoichiometric ratio, with the contents of Pb3O4, La2O3, ZrO2 and TiO2 being the same as those in the comparative example, and 6wt% Y2O3 was added based on the actual mass ratio of the prepared powder.

[0060] (2) The powder prepared in step (1) is initially mixed by wet ball milling, dried and ground, compacted in a crucible and pre-fired using a two-stage pre-fired method. The pre-fired heating rate is 3℃ / min, and the temperature is raised to 850℃. Then, the temperature is lowered to 800℃ at a cooling rate of 10℃ / min and kept at that temperature for 3 hours. The temperature is then lowered to room temperature at a cooling rate of 3℃ / min.

[0061] (3) Grind the pre-fired block obtained in step (2) and ball mill it to refine it. Dry and grind it through a 200-mesh sieve to obtain powder. Prepare it according to the casting slurry formula (same as in Example 1). After ball milling for 12 hours, perform casting process to obtain a 20μm thick casting film.

[0062] (4) Cut and stack the cast film obtained in step (3) to 1 mm, press it through a tablet press and a cold isostatic press to obtain a ceramic green body, and then debind and sinter the ceramic green body in sequence. The debinding temperature is 600℃, the heating rate is 1℃ / min, the cooling rate is 4℃ / min, and the holding time is 5h. The sintering operation will be carried out in a reducing atmosphere (sintering in lead-containing powder). The volume ratio of reducing gas during sintering is 200:1 for nitrogen and 1140℃, the heating rate is 5℃ / min, the cooling rate is 7℃ / min, the holding time is 3h, and the temperature is cooled to room temperature.

[0063] Comparative Example 1

[0064] A general formula for ceramic structures: Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 O3, the ceramic preparation method includes the following steps:

[0065] (1) Powders were prepared in stoichiometric ratios, with the molar ratio of Pb3O4, La2O3, ZrO2 and TiO2 powders being 1.455:0.088:4.379:0.044.

[0066] (2) The powder prepared in step (1) is initially mixed by wet ball milling for 24 hours. After the components are fully mixed, dried and ground, it is compacted in a crucible and pre-fired using a two-stage pre-fired method. The pre-fired heating rate is 3℃ / min, and the temperature is raised to 850℃. Then, the temperature is lowered to 800℃ at a cooling rate of 10℃ / min and held for 3 hours. The temperature is then lowered to room temperature at a cooling rate of 3℃ / min.

[0067] (3) Grind the pre-fired block obtained in step (2) and ball mill it to refine it. Dry and grind it through a 200-mesh sieve to obtain powder. Prepare it according to the casting slurry formula (same as in Example 1). After ball milling for 12 hours, perform casting process to obtain a 20μm thick casting film.

[0068] (4) Cut and stack the cast film obtained in step (3) and press it. After stacking for 1 mm, press it with a tablet press and a cold isostatic press to obtain a ceramic green body. The ceramic green body is then debonded and sintered in sequence. The debonding and sintering temperature is 550℃, the heating rate is 1℃ / min, the cooling rate is 4℃ / min, and the holding time is 5h. The sintering operation will be carried out in a reducing atmosphere (sintering in lead-containing powder). The volume ratio of reducing gas during sintering is 200:1 for nitrogen and 1180℃, the heating rate is 5℃ / min, the cooling rate is 7℃ / min, and the holding time is 3h.

[0069] Comparative Example 2

[0070] The general structural formula of a ceramic is: Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 The ceramic preparation method, consisting of O3 + 8wt%Y2O3, includes the following steps:

[0071] (1) Powder was prepared in stoichiometric ratio, with the contents of Pb3O4, La2O3, ZrO2 and TiO2 being the same as those in the comparative example, and 8wt% Y2O3 was added based on the actual mass ratio of the prepared powder.

[0072] (2) The powder prepared in step (1) is initially mixed by wet ball milling, dried and ground, compacted in a crucible and pre-fired using a two-stage pre-fired method. The pre-fired heating rate is 3℃ / min, and the temperature is raised to 850℃. Then, the temperature is lowered to 800℃ at a cooling rate of 10℃ / min and kept at that temperature for 3 hours. The temperature is then lowered to room temperature at a cooling rate of 3℃ / min.

[0073] (3) Grind the pre-fired block obtained in step (2) and ball mill it to refine it. Dry and grind it through a 200-mesh sieve to obtain powder. Prepare it according to the casting slurry formula (same as in Example 1). After ball milling for 12 hours, perform casting process to obtain a 20μm thick casting film.

[0074] (4) Cut and stack the cast film obtained in step (3) to 1 mm, press it through a tablet press and a cold isostatic press to obtain a ceramic green body, and then debind and sinter the ceramic green body in sequence. The debinding temperature is 550℃, the heating rate is 1℃ / min, the cooling rate is 4℃ / min, and the holding time is 5h. The sintering operation will be carried out in a reducing atmosphere (sintering in lead-containing powder). The volume ratio of reducing gas during sintering is 200:1 for nitrogen and 1180℃, the heating rate is 5℃ / min, the cooling rate is 7℃ / min, the holding time is 3h, and the temperature is cooled to room temperature.

[0075] Performance testing methods and data

[0076] Performance tests were conducted on the examples and comparative examples.

[0077] 1. Perform XRD testing, such as... Figure 1 As shown, Comparative Examples 1 and 2, as well as Examples 1, 2, and 3, all formed pure perovskite structures; the splitting peak at 44.5° indicates that the main phase has a tetragonal perovskite crystal structure; the synthesis of the second phase yttrium zirconate can be confirmed by comparison with the PDF card (PDF#97-019-5418); the diffraction peaks of the comparative examples and examples show obvious crystal structures, indicating that a stable crystal structure can still be obtained under reducing atmosphere sintering conditions.

[0078] 2. Perform SEM testing, such as... Figure 2 As shown, Example 2, as the optimal composition, exhibits a more complete morphological structure in SEM testing. Compared with Comparative Example 1, Comparative Example 2, Example 1, and Example 3, it shows denser packing, indicating that the addition of an appropriate amount of Y2O3 promotes grain growth and improves the densification of the ceramic.

[0079] 3. Au (gold) electrodes are formed on the upper and lower surfaces of the sample by ion sputtering to test its performance (using the ferroelectric integrated testing system from Radiant, USA), PE test (…). Figure 3 ), energy storage density and efficiency ( Figure 4 The data is listed in Table 1.

[0080] Table 1

[0081]

[0082] As shown in Table 1, it can also be done through Figure 4 Through intuitive performance comparison, the regulatory effect of Y2O3 addition on the performance of antiferroelectric energy storage ceramics is clearly demonstrated: 4wt% is the optimal addition ratio, at which point the second phase works synergistically with the main phase to achieve a balance between high energy storage density and high energy storage efficiency; excessive or no addition of Y2O3 will lead to a decrease in performance.

Claims

1. A reduction-resistant two-phase antiferroelectric energy storage ceramic, characterized in that, The general structural formula of the ceramic is: Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 O3+xwt%Y2O3; where x takes values ​​in the range of 3≤x≤5; and Y2O3 can react with Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 O3 forms the second phase of ceramic, yttrium zirconate.

2. The ceramic according to claim 1, characterized in that, The raw materials for preparing the ceramic include: Pb3O4, La2O3, ZrO2, TiO2 and Y2O3.

3. The ceramic according to claim 2, characterized in that, The raw materials for preparing the ceramic also include solvents and additives, wherein the additives include at least one of dispersants, binders, plasticizers, and homogenizers.

4. A method for preparing ceramics according to claim 3, characterized in that, Includes the following steps: Pb3O4, La2O3, ZrO2, TiO2, and Y2O3 were prepared according to the stoichiometric ratio of the general formula for ceramic structure. Pb3O4, La2O3, ZrO2, TiO2, and Y2O3 were ball-milled and mixed evenly, dried, pre-sintered, and then ball-milled again to obtain powder. The powder was ball-milled and mixed with solvent and additives to form a casting slurry, and a casting film was prepared by casting process. The film was then laminated and pressed to obtain a ceramic green body. After the ceramic green body was debinded, it was sintered in a reducing atmosphere to obtain ceramic.

5. The method for preparing ceramics according to claim 4, characterized in that, The pre-sintering treatment employs a two-stage pre-firing process. The temperature of the two-stage pre-firing is 700~900℃, the heating rate is 1~8℃ / min, the cooling rate is 3~15℃ / min, and the holding time is 2~5h.

6. The method for preparing ceramics according to claim 4, characterized in that, The temperature for discharging the adhesive is 450℃~700℃, the heating rate is 0.5~3℃ / min, the cooling rate is 3~5℃ / min, and the holding time is 3~5h.

7. The method for preparing ceramics according to claim 4, characterized in that, The reducing atmosphere includes nitrogen and hydrogen, with a nitrogen to hydrogen volume ratio of 200:(0.5~3); the sintering temperature is 1000~1200℃, the heating rate is 3~8℃ / min, the cooling rate is 3~10℃ / min, and the holding time is 3~5h.

8. An application of the ceramic according to any one of claims 1-3, characterized in that, It is used in the manufacture of dielectric energy storage capacitors.

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