High-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with high breakdown and high polarization and preparation method of high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material

Abstract

The invention discloses a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with high breakdown and high polarization and a preparation method of the high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material, and belongs to the field of capacitor ceramic dielectric materials. A ferroelectric-paraelectric composite ceramic system is selected as the ceramic matrix material, the chemical formula is xBi < 0.5 > Na < 0.5 > TiO < 3-(1-x) > SrTiO < 3 >, and x is more than or equal to 0.2 and less than or equal to 0.8; and a SiO2 layer is attached to the ceramic substrate by adopting a spin coating process, and the high polarization characteristic of the ceramic substrate is retained while the breakdown resistance of the ceramic is enhanced by introducing an interface layer, so that excellent energy storage performance is obtained. The ferroelectric-paraelectric composite ceramic material is simple in preparation process flow, efficient in preparation and low in cost, the provided ferroelectric-paraelectric composite ceramic material is free of lead, environmentally friendly and excellent in performance, and the discharge energy density of the ferroelectric-paraelectric composite ceramic material under the breakdown strength of 670 kV / cm reaches up to 9.85 J / cm < 3 >.

Description

Technical Field

[0001] This invention relates to the field of capacitor ceramic dielectric materials, specifically to a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization, and its preparation method. Background Technology

[0002] Ceramic dielectric capacitors are highly competitive in electronic systems due to their high power density, strong voltage withstand capability, and outstanding reliability. However, their relatively poor energy storage density remains an obstacle to meeting the integration and miniaturization requirements of advanced electronic systems. Since ceramic dielectrics primarily store energy through polarization, and considering the polarization characteristics exhibited by their hysteresis loops, it is essential to optimize the polarization intensity and breakdown field strength of ceramic dielectrics to improve their energy storage density.

[0003] Ferroelectric dielectrics, such as BaTiO3 and Bi 0.5 Na 0.5 TiO3 and paraelectric dielectrics, such as SrTiO3 and SrZrO3, are two typical ceramic dielectrics, each with significant advantages: ferroelectric dielectrics have high polarization but low breakdown field strength and severe polarization hysteresis with the electric field; paraelectric dielectrics have high breakdown field strength and high energy storage efficiency, but low polarization. Therefore, because it is impossible to simultaneously possess both high polarization and high breakdown field strength, both ferroelectric and paraelectric ceramic dielectrics have relatively low energy storage densities, limiting their application in miniaturized and integrated energy storage circuits. Therefore, synergistically optimizing the relationship between polarization, breakdown field strength, and polarization electric field response of ceramic dielectric materials is key to improving the energy storage density and efficiency of ceramic dielectrics, and is also an inevitable requirement for ceramic dielectric materials to achieve practical applications in energy storage. Summary of the Invention

[0004] The purpose of this invention is to provide a method for preparing a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material that combines high breakdown and high polarization. The preparation process is simple, the material cost is low, the preparation is efficient, and it is lead-free and environmentally friendly.

[0005] Another object of the present invention is to provide a composite dielectric material prepared by a preparation method, which has excellent energy storage performance.

[0006] To achieve the above-mentioned technical objectives, the technical solution adopted by the present invention is as follows: On the one hand, the present invention provides a method for preparing a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material that combines high breakdown and high polarization, specifically including the following steps: a. First, based on the chemical formula Bi 0.5 Na 0.5TiO3 was weighed separately from raw material powders Bi2O3, Na2CO3, and TiO2, and SrCO3 and TiO2 were weighed separately according to the chemical formula SrTiO3. Anhydrous ethanol was added to each group of weighed powders, and the mixture was ball-milled using a planetary ball mill to obtain a uniformly mixed slurry. After drying, the slurry was calcined to synthesize a single perovskite structure powder. b. According to the chemical formula x Bi 0.5 Na 0.5 TiO3-(1- x SrTiO3, 0.2≤ x ≤0.8% of the synthesized Bi were weighed separately. 0.5 Na 0.5 TiO3 and SrTiO3 powders were ball-milled twice with anhydrous ethanol as the ball milling medium to obtain a uniformly mixed slurry. c. Add 12-20 wt% polyvinyl butyral and 5-10 wt% tributyl ester to the slurry obtained in step b, and tumble for 10-20 hours to obtain a casting slurry. Then cast the slurry to obtain a ceramic film tape, thus obtaining the ferroelectric-paraelectric composite ceramic material matrix. d. Spin-coating SiO2 sol onto a ferroelectric-paraelectric composite ceramic material matrix to obtain a green compact of the composite dielectric material; e. The green body obtained in step d is sintered. First, the temperature is raised to 600℃ and held for 2 hours to remove the binder. Then, the temperature is raised to 1100~1250℃ and held for 1~3 hours to densify the sinter. Then, it is cooled with the furnace to obtain the ferroelectric-paraelectric ceramic matrix composite dielectric material.

[0007] Preferably, the ball milling speed in steps a and b is 200~300 r / min, and the ball milling time is 5 hours.

[0008] Preferably, the calcination conditions described in step a are calcination at 800~1000℃ for 2~5 hours.

[0009] Preferably, the ceramic membrane strip mentioned in step c is selected as a single-component ceramic membrane strip or a different-component ceramic membrane strip, depending on the designed ceramic structure. x of x Bi 0.5 Na 0.5 TiO3-(1- x SrTiO3 films are stacked together to obtain a ceramic matrix.

[0010] Preferably, the ceramic film strip described in step c has a thickness of 20~100µm.

[0011] Preferably, the SiO2 sol preparation method in step d is as follows: ① Add tetraethyl orthosilicate to anhydrous ethanol and stir for 20-60 minutes to obtain solution A; ② Add ammonia water to anhydrous ethanol and stir for 20-60 minutes to obtain solution B; ③ Add solution B dropwise to solution A at a volume ratio of tetraethyl orthosilicate to ammonia of 6-8:1. After the addition is complete, continue stirring for 20-60 minutes. Then add polyethylene glycol to the system and stir for 1-3 hours. Seal and refrigerate for 3-7 days to obtain SiO2 sol.

[0012] On the other hand, the present invention also provides a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization, prepared by the above-described method.

[0013] Compared with the prior art, the present invention has the following advantages: 1. This invention uses tape casting for layered design and spin-coating SiO2 into the BNT-ST-based green ceramic system, which enables the ceramic dielectric material to have excellent breakdown field strength and polarization intensity and high discharge energy density. This work provides a feasible way to optimize ceramic properties and shows great potential in the field of high energy storage.

[0014] 2. Compared with other methods, the spin-coating method used in this invention to add a SiO2 layer to the surface of a ceramic substrate is simpler and less costly. Furthermore, samples can be prepared under mild conditions without the need for high temperature, high vacuum, or high pressure, effectively reducing contamination, saving energy, and improving cost-effectiveness, making it suitable for industrial applications. Attached Figure Description

[0015] Figure 1 The surface scanning electron microscope morphology of the sample obtained in Example 3; Figure 2 The sample prepared in Comparative Example 1 P - E Backline; Figure 3 It is the sample prepared in Example 1. P - E Backline; Figure 4 The sample prepared in Comparative Example 2 P - E Backline; Figure 5 The sample obtained in Example 2 P - E Backline; Figure 6 The sample prepared in Comparative Example 3 P - E Backline; Figure 7 It is the sample prepared in Example 3. P - E Return line. Detailed Implementation

[0016] To address the challenge of existing ceramic materials simultaneously possessing high polarization strength and high breakdown field strength, this invention combines a layered design with a spin-coating process. The layered design combines a ferroelectric layer with high polarization strength and a paraelectric layer with high breakdown field strength, thus achieving a balance between polarization and breakdown, resulting in a ceramic dielectric with excellent overall energy storage performance and high design flexibility. Furthermore, the layered process can be matched with the fabrication process of multilayer ceramic capacitors, facilitating the device fabrication of dielectric materials.

[0017] Spin coating is a rapid and simple method for applying a thin coating layer to a substrate surface. Spin coating technology utilizes centrifugal force to evenly distribute a thin coating layer on a flat substrate. A small amount of liquid coating material is applied to the center of the substrate, which is then placed on a spinning device, and the substrate is rapidly rotated to distribute the coating material. During spin coating, the coating thickness can be controlled by changing factors such as rotation speed, coating solution viscosity, and solvent volatility. SiO2 is an excellent insulating material with low conductivity, low dielectric constant, and high breakdown strength. Spin coating SiO2 onto the surface of ceramic materials as a low-dielectric barrier layer can improve the overall breakdown strength. Moreover, the spin coating process is simple, efficient, and low-cost, making it suitable for industrial applications.

[0018] To make the contents of this invention easier to understand, the essential features and advantages of this invention are further illustrated below with reference to specific embodiments. This invention is not limited to the embodiments stated.

[0019] Comparative Example 1 The composition of the ferroelectric-paraelectric ceramic dielectric material in this comparative example is: 0.6Bi. 0.5 Na 0.5 The specific preparation steps for TiO3-0.4SrTiO3 (0.6BNT-0.4ST) are as follows: a. First, based on the chemical formula Bi 0.5 Na 0.5 TiO3 was weighed separately from raw material powders Bi2O3, Na2CO3, and TiO2. SrCO3 and TiO2 were weighed separately according to the chemical formula SrTiO3. Anhydrous ethanol was added to each weighed powder group, and the mixture was ball-milled using a planetary ball mill at a speed of 300 r / min for 5 h to obtain a uniformly mixed slurry, which was then dried at 80℃. b. Dry Bi 0.5 Na 0.5TiO3 powder was calcined at 850℃ for 5 hours, and SrTiO3 powder was calcined at 950℃ for 3 hours to synthesize a single perovskite structure powder; further, according to the chemical formula 0.6Bi 0.5 Na 0.5 Bi synthesized by weighing TiO3-0.4SrTiO3 0.5 Na 0.5 TiO3 and SrTiO3 powders were ball-milled twice with anhydrous ethanol as the ball milling medium at a speed of 300 r / min for 5 h to obtain a uniformly mixed slurry. c. Add 16wt% polyvinyl butyral and 8wt% tributyl ester to the obtained slurry, and tumble for 15 hours to obtain a casting slurry. Then cast to obtain a 30µm ceramic film tape, thus obtaining a ceramic matrix. d. The above-mentioned film strip green body is sintered. First, the temperature is raised to 600℃ and held for 2 hours to remove the binder. Then, the temperature is raised to 1170℃ and held for 3 hours to densify the sinter. Then, it is cooled in the furnace to obtain the ferroelectric-paraelectric ceramic composite dielectric material.

[0020] Example 1 In this embodiment, the composition of the ferroelectric-paraelectric ceramic matrix is: 0.6Bi. 0.5 Na 0.5 TiO3-0.4SrTiO3, with a SiO2 layer spin-coated onto the substrate surface, referred to as 0.6BNT-0.4ST@Si, the specific preparation steps are as follows: a. First, based on the chemical formula Bi 0.5 Na 0.5 TiO3 was weighed separately from raw material powders Bi2O3, Na2CO3, and TiO2. SrCO3 and TiO2 were weighed separately according to the chemical formula SrTiO3. Anhydrous ethanol was added to each weighed powder group, and the mixture was ball-milled using a planetary ball mill at a speed of 300 r / min for 5 h to obtain a uniformly mixed slurry, which was then dried at 80℃. b. Dry Bi 0.5 Na 0.5 TiO3 powder was calcined at 850℃ for 5 hours, and SrTiO3 powder was calcined at 950℃ for 3 hours to synthesize a single perovskite structure powder; further, according to the chemical formula 0.6Bi 0.5 Na 0.5 Bi synthesized by weighing TiO3-0.4SrTiO3 0.5 Na 0.5 TiO3 and SrTiO3 powders were ball-milled twice with anhydrous ethanol as the ball milling medium at a speed of 300 r / min for 5 h to obtain a uniformly mixed slurry. c. Add 16wt% polyvinyl butyral and 8wt% tributyl ester to the obtained slurry, and tumble for 15 hours to obtain a casting slurry. Then cast to obtain a 30µm ceramic film tape, thus obtaining a ceramic matrix. d. Spin-coating SiO2 sol onto a ferroelectric-paraelectric composite ceramic material matrix to obtain a green compact of the composite dielectric material; e. The above-mentioned film strip green body is sintered. First, the temperature is raised to 600℃ and held for 2 hours to remove the binder. Then, the temperature is raised to 1160℃ and held for 3 hours to densify the sinter. Then, it is cooled in the furnace to obtain the ferroelectric-paraelectric ceramic composite dielectric material.

[0021] The method for preparing SiO2 sol in step d is as follows: ① Add anhydrous ethanol to beaker A, then add tetraethyl orthosilicate and stir magnetically for 30 minutes; ② Add anhydrous ethanol to beaker B, then add ammonia and stir magnetically for 30 minutes; ③According to the volume ratio of tetraethyl orthosilicate to ammonia water of 6.5:1, the solution in beaker B is added dropwise to beaker A using a dropper. After the addition is complete, the mixture is stirred for 30 minutes. Then, polyethylene glycol is added to beaker B and the mixture is magnetically stirred for 2 hours. The mixture is then sealed and refrigerated for 5 days to obtain SiO2 sol.

[0022] Comparative Example 2 The composition of the ferroelectric-paraelectric ceramic dielectric material in this comparative example is: 0.4Bi. 0.5 Na 0.5 The preparation steps for TiO3-0.6SrTiO3 (0.4BNT-0.6ST) are the same as those for Comparative Example 1, except that the sintering temperature in step d is changed to 1200℃. The other process parameters are also the same as those for Comparative Example 1.

[0023] Example 2 In this embodiment, the composition of the ferroelectric-paraelectric ceramic matrix is: 0.4Bi. 0.5 Na 0.5 TiO3-0.6SrTiO3, with a SiO2 layer spin-coated on the substrate surface, referred to as 0.4BNT-0.6ST@Si, the specific preparation steps are the same as in Example 1, except that the sintering temperature in step d is changed to 1180℃, and the other process parameters are also the same as in Example 1.

[0024] Comparative Example 3 The ferroelectric-paraelectric ceramic matrix in this comparative example employs a multilayer design, with the multilayer matrix composition being 0.6Bi. 0.5 Na 0.5 TiO3-0.4SrTiO3 and 0.4Bi 0.5 Na 0.5The specific preparation steps for TiO3-0.6SrTiO3 are as follows: a) First, according to the chemical formula Bi 0.5 Na 0.5 TiO3 was weighed separately from raw material powders Bi2O3, Na2CO3, and TiO2. SrCO3 and TiO2 were weighed separately according to the chemical formula SrTiO3. Anhydrous ethanol was added to each weighed powder group, and the mixture was ball-milled using a planetary ball mill at a speed of 300 r / min for 5 h to obtain a uniformly mixed slurry, which was then dried at 80℃. b. Dry Bi 0.5 Na 0.5 TiO3 powder was calcined at 850℃ for 5 hours, and SrTiO3 powder was calcined at 950℃ for 3 hours to synthesize a single perovskite structure powder; further, according to the chemical formula 0.6Bi 0.5 Na 0.5 TiO3-0.4SrTiO3 and 0.4Bi 0.5 Na 0.5 Bi synthesized from TiO3 and 0.6SrTiO3 were weighed separately. 0.5 Na 0.5 TiO3 and SrTiO3 powders were ball-milled twice with anhydrous ethanol as the ball milling medium at a speed of 300 r / min for 5 h to obtain uniformly mixed 0.6BNT-0.4ST and 0.4BNT-0.6ST slurries, respectively. c. Add 16 wt% polyvinyl butyral and 8 wt% tributyl ester to the obtained slurry, and tumble for 15 hours to obtain a casting slurry. Then cast 0.6BNT-0.4ST and 0.4BNT-0.6ST ceramic film tapes with a thickness of 30 µm respectively. d. The 0.6BNT-0.4ST and 0.4BNT-0.6ST ceramic film strips are pressed together by hot pressing to form a laminated ceramic 0.6BNT-0.4ST / 0.4BNT-0.6ST film strip; e. The above-mentioned film strip green body is sintered. First, the temperature is raised to 600℃ and held for 2 hours to remove the binder. Then, the temperature is raised to 1180℃ and held for 3 hours to densify the sinter. Then, it is cooled in the furnace to obtain the ferroelectric-paraelectric ceramic composite dielectric material.

[0025] Example 3 In this embodiment, the ferroelectric-paraelectric ceramic matrix adopts a multilayer design, and the composition of the multilayer matrix is ​​0.6Bi. 0.5 Na 0.5 TiO3-0.4SrTiO3 and 0.4Bi 0.5 Na 0.5TiO3-0.6SrTiO3, with a SiO2 layer spin-coated onto the surface of this laminated substrate, referred to as 0.6BNT-0.4ST / 0.4BNT-0.6ST @Si, the specific preparation steps are as follows: a. First, based on the chemical formula Bi 0.5 Na 0.5 TiO3 was weighed separately from raw material powders Bi2O3, Na2CO3, and TiO2. SrCO3 and TiO2 were weighed separately according to the chemical formula SrTiO3. Anhydrous ethanol was added to each weighed powder group, and the mixture was ball-milled using a planetary ball mill at a speed of 300 r / min for 5 h to obtain a uniformly mixed slurry, which was then dried. b. Dry Bi 0.5 Na 0.5 TiO3 powder was calcined at 850 °C for 5 h, and SrTiO3 powder was calcined at 950 °C for 3 h to synthesize a single perovskite structure powder; further, according to the chemical formula 0.6Bi 0.5 Na 0.5 TiO3-0.4SrTiO3 and 0.4Bi 0.5 Na 0.5 Bi synthesized from TiO3 and 0.6SrTiO3 were weighed separately. 0.5 Na 0.5 TiO3 and SrTiO3 powders were ball-milled twice with anhydrous ethanol as the ball milling medium at a speed of 300 r / min for 5 h to obtain uniformly mixed 0.6BNT-0.4ST and 0.4BNT-0.6ST slurries, respectively. c. Add 16 wt% polyvinyl butyral and 8 wt% tributyl ester to the obtained slurry, and tumble for 15 hours to obtain a casting slurry. Then cast 0.6BNT-0.4ST and 0.4BNT-0.6ST ceramic film tapes with a thickness of 30 µm respectively. d. The 0.6BNT-0.4ST and 0.4BNT-0.6ST ceramic film strips are pressed together by hot pressing to form a laminated ceramic 0.6BNT-0.4ST / 0.4BNT-0.6ST film strip; e. Spin-coating SiO2 sol onto a multilayer ceramic film substrate to obtain a green compact of composite dielectric material; f. The above-mentioned film strip green body is sintered. First, the temperature is raised to 600℃ and held for 2 hours to remove the binder. Then, the temperature is raised to 1170℃ and held for 3 hours to densify the sinter. Then, it is cooled in the furnace to obtain the ferroelectric-paraelectric ceramic composite dielectric material.

[0026] The method for preparing SiO2 sol in step e is the same as in Example 1.

[0027] The performance of the ceramic dielectric materials prepared in Examples 1-3 and Comparative Examples 1-3 was tested, as follows: 1. Microscopic morphology analysis was performed on Example 3, and the results are as follows: Figure 1 As shown, the sample surface exhibits uniform grain morphology and high density, with no obvious pores observed, indicating that the sintering quality of the example is good.

[0028] 2. The ceramic dielectric materials prepared in Examples 1-3 and Comparative Examples 1-3 were subjected to... P - E Backtracking test, P - E The return lines are respectively as follows Figures 2 to 7 As shown.

[0029] Based on the following formula, Figures 2 to 7 The discharge energy storage density and energy storage efficiency of each embodiment can be calculated: (1) (2) (3) in W total The energy storage density of the dielectric, W dis This represents the actual discharge energy density of the dielectric. W loss For the energy loss generated, P max For maximum polarization, P r For remanent polarization, η For energy storage efficiency.

[0030] The specific performance test results are summarized in Table 1.

[0031] Table 1. Energy storage performance parameters of the samples prepared in the examples Figure 2 The sample prepared in Comparative Example 1 P - E Backline; Figure 3 It is the sample prepared in Example 1. P - E Backline; Figure 4 The sample prepared in Comparative Example 2 P - E Backline; Figure 5 The sample obtained in Example 2 P - E Backline; Figure 6 The sample prepared in Comparative Example 3P - E Backline; Figure 7 It is the sample prepared in Example 3. P - E Return line.

[0032] Combination Figures 2 to 7 As shown in Table 1, the breakdown field strength of Comparative Example 1 and Comparative Example 2 is relatively low. The breakdown field strength of Examples 1 and 2, prepared by spin-coating SiO2 onto the BNT-ST system, is increased. This demonstrates that spin-coating SiO2 can increase the breakdown field strength and improve the discharge energy density. This is because a SiO2 layer is attached to the ceramic substrate. By introducing an interface layer, the breakdown resistance of the ceramic is enhanced while retaining the high polarization characteristics of the ceramic substrate, and its energy storage efficiency is improved to a certain extent. The stacked design of Comparative Example 3 also significantly improved the breakdown field strength and polarization intensity of the ceramic sample. Due to the stacked design, combined with the characteristics of ferroelectric and paraelectric ceramic dielectrics, the high polarization of ferroelectric ceramics and the high breakdown field strength of paraelectric ceramics are combined in the stacked ceramics. Simultaneously, the coexistence of multiple ferroelectric and paraelectric properties can reduce polarization hysteresis, ultimately achieving a breakdown field strength of 540 kV / cm. Further spin-coating of SiO2 into Comparative Example 3 yielded Example 3, which showed a further improvement in breakdown field strength to 670 kV / cm, achieving an ultra-high energy storage density of 9.85 J / cm². 3 Furthermore, the energy storage efficiency of the embodiments modified by spin coating was improved to a certain extent.

[0033] This invention employs a layered design through tape casting and spin-coating SiO2 into a BNT-ST-based green ceramic system, resulting in ceramic dielectric materials with excellent breakdown field strength and polarization intensity, as well as high discharge energy density. This work provides a feasible approach to optimizing ceramic properties and shows great potential in the field of high-energy storage.

[0034] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any modifications, equivalent substitutions, and improvements made by those skilled in the art within the scope of the technology disclosed in the present invention, and within the spirit and principles of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A method for preparing a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material possessing both high breakdown and high polarization, characterized in that, Includes the following steps: a. First, based on the chemical formula Bi 0.5 Na 0.5 TiO3 was weighed separately from raw material powders Bi2O3, Na2CO3, and TiO2, and SrCO3 and TiO2 were weighed separately according to the chemical formula SrTiO3. Anhydrous ethanol was added to each group of weighed powders, and the mixture was ball-milled using a planetary ball mill to obtain a uniformly mixed slurry. After drying, the slurry was calcined to synthesize a single perovskite structure powder. b. According to the chemical formula x Bi 0.5 Na 0.5 TiO3-(1- x SrTiO3, 0.2≤ x ≤0.8% of the synthesized Bi were weighed separately. 0.5 Na 0.5 TiO3 and SrTiO3 powders were ball-milled twice with anhydrous ethanol as the ball milling medium to obtain a uniformly mixed slurry. c. Add 12-20 wt% polyvinyl butyral and 5-10 wt% tributyl ester to the slurry obtained in step b, and tumble for 10-20 hours to obtain a casting slurry. Then cast the slurry to obtain a ceramic film tape, thus obtaining the ferroelectric-paraelectric composite ceramic material matrix. d. Spin-coating SiO2 sol onto a ferroelectric-paraelectric composite ceramic material matrix to obtain a green compact of the composite dielectric material; e. The green body obtained in step d is sintered. First, the temperature is raised to 600℃ and held for 2 hours to remove the binder. Then, the temperature is raised to 1100~1250℃ and held for 1~3 hours to densify the sinter. Then, it is cooled with the furnace to obtain the ferroelectric-paraelectric ceramic matrix composite dielectric material.

2. The method for preparing a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization as described in claim 1, characterized in that: The ball milling speed in steps a and b is 200~300 r / min, and the ball milling time is 5 hours.

3. The preparation method of a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization as described in claim 1, characterized in that: The calcination conditions described in step a are calcination at 800~1000℃ for 2~5 hours.

4. The preparation method of a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization as described in claim 1, characterized in that: The ceramic membrane tape mentioned in step c, depending on the designed ceramic structure, can be selected as a single-component ceramic membrane tape or a tape with different components. x of x Bi 0.5 Na 0.5 TiO3-(1- x SrTiO3 films are stacked together to obtain a ceramic matrix.

5. The preparation method of a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization according to claim 1, characterized in that: The ceramic film strip described in step c has a thickness of 20~100 µm.

6. The method for preparing a high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material with both high breakdown and high polarization according to claim 1, characterized in that: The method for preparing SiO2 sol in step d is as follows: ① Add tetraethyl orthosilicate to anhydrous ethanol and stir for 20-60 minutes to obtain solution A; ② Add ammonia water to anhydrous ethanol and stir for 20-60 minutes to obtain solution B; ③ Add solution B dropwise to solution A at a volume ratio of tetraethyl orthosilicate to ammonia of 6-8:

1. After the addition is complete, continue stirring for 20-60 minutes. Then add polyethylene glycol to the system and stir for 1-3 hours. Seal and refrigerate for 3-7 days to obtain SiO2 sol.

7. A high-energy-storage ferroelectric-paraelectric ceramic-based composite dielectric material possessing both high breakdown and high polarization, characterized in that, It is prepared by the preparation method according to any one of claims 1 to 6.

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