A high energy storage antiferroelectric multilayer capacitor with heterostructure and preparation method thereof

Abstract

The present invention belongs to the technical field of electronic information materials and components, and discloses a high-energy storage antiferroelectric multilayer capacitor with a heterostructure and a preparation method thereof. The antiferroelectric multilayer capacitor with a heterostructure comprises multiple antiferroelectric material layers stacked from bottom to top, with an electrode disposed between two adjacent antiferroelectric material layers; the multiple antiferroelectric material layers simultaneously include antiferroelectric material layers with a large electrostrain and antiferroelectric material layers with a small electrostrain; and the upper and lower layers adjacent to each antiferroelectric material layer with a large electrostrain are both antiferroelectric material layers with a small electrostrain. The present invention uses both antiferroelectric material layers with a large electrostrain and antiferroelectric material layers with a small electrostrain, and ensures that the upper and lower layers adjacent to each antiferroelectric material layer with a large electrostrain are both antiferroelectric material layers with a small electrostrain. The resulting high-energy storage antiferroelectric multilayer capacitor with a heterostructure has both high energy storage density and high energy storage efficiency.

Description

Technical Field

[0001] The present invention belongs to the technical field of electronic information materials and components, and more specifically, relates to a high-energy storage antiferroelectric multilayer ceramic capacitor with a heterogeneous structure and a preparation method thereof. Background Art

[0002] Dielectric capacitors, such as dielectric ceramic capacitors, are widely used in military applications such as aerospace and advanced weaponry due to their ultra-high discharge power density, as well as in consumer and industrial applications such as mobile communications, new energy vehicles, and smart grids. However, current dielectric ceramic capacitors offer only low energy storage density, which cannot meet the demands of electronic devices moving towards greater integration, miniaturization, and lightweighting. Therefore, there is an urgent need to develop dielectric ceramic capacitors with high energy storage performance.

[0003] The key factor affecting the energy storage performance of dielectric ceramic capacitors is the energy storage dielectric material, which primarily includes linear dielectrics, ferroelectrics, relaxor ferroelectrics, and antiferroelectrics. Antiferroelectrics, due to their electric field-induced antiferroelectric-ferroelectric phase transition, exhibit a unique double hysteresis loop, and their dielectric constant increases with increasing electric field, making them considered ideal energy storage media. However, while existing antiferroelectric energy storage materials (such as lead zirconate-based materials) can typically be modified through doping to increase energy storage density, this often results in a decrease in energy storage efficiency. This means that these materials struggle to achieve both improved energy storage density and improved energy storage efficiency. Due to their low energy storage efficiency, the device generates more Joule heat during operation, hindering its reusability, thus placing higher demands on energy storage efficiency. Furthermore, while the interdigitated electrode structure of existing antiferroelectric multilayer ceramic capacitors can further improve energy storage density, due to their small size and poor heat dissipation, the heat generated by energy loss is more likely to lead to thermal breakdown, thus affecting the normal operation of the capacitor. Therefore, improving energy storage efficiency can not only save costs but also extend the life of the device. In the context of energy conservation and emission reduction, it is of great significance to achieve the combination of high energy storage density and high energy storage efficiency. Summary of the Invention

[0004] In response to the above defects or improvement needs of the prior art, the purpose of the present invention is to provide a high-energy storage antiferroelectric multilayer capacitor with a heterostructure and a preparation method thereof, wherein the structure of the multilayer antiferroelectric material layer is improved, and the multilayer antiferroelectric material layer is constructed using an antiferroelectric material layer with a larger electrostrain and an antiferroelectric material layer with a smaller electrostrain as the active layer of the device, so that except for the upper end face and the lower end face of the active layer, the upper antiferroelectric material layer and the lower antiferroelectric material layer adjacent to each antiferroelectric material layer with a larger electrostrain are both antiferroelectric material layers with a smaller electrostrain. The obtained heterostructured high-energy storage antiferroelectric multilayer capacitor has both high energy storage density and high energy storage efficiency, which can effectively solve the problem that the existing antiferroelectric multilayer capacitors are difficult to achieve both high energy storage density and high energy storage efficiency and have poor reliability.

[0005] To achieve the above objectives, according to one aspect of the present invention, there is provided an antiferroelectric multilayer capacitor having a heterostructure, characterized in that it comprises a plurality of antiferroelectric material layers stacked from bottom to top, wherein electrodes are provided on the upper and lower surfaces of each antiferroelectric material layer, and two adjacent antiferroelectric material layers share a common electrode;

[0006] The multilayer antiferroelectric material layer is prepared by the same sintering process. According to the electrostrain of each antiferroelectric material layer in the multilayer antiferroelectric material layer, the multilayer antiferroelectric material layer includes both an antiferroelectric material layer with a larger electrostrain and an antiferroelectric material layer with a smaller electrostrain. In addition, in the multilayer antiferroelectric material layer, except for the upper end surface and the lower end surface, the upper antiferroelectric material layer and the lower antiferroelectric material layer adjacent to each antiferroelectric material layer with a larger electrostrain are both antiferroelectric material layers with a smaller electrostrain.

[0007] Among them, the electrostrain S of the antiferroelectric material layer with larger electrostrain is greater than 0.20%, the electrostrain S of the antiferroelectric material layer with smaller electrostrain is less than or equal to 0.20%, and the electrostrain difference ΔS between the two is greater than 0.10%; the electrostrain S of each antiferroelectric material layer corresponds to the electric field strength corresponding to when the polarization intensity of each antiferroelectric material in the multi-layer antiferroelectric material layer reaches saturation, and the minimum electric field strength is used as the electrostrain test electric field, and each antiferroelectric material layer is subjected to electrostrain testing.

[0008] As a further preferred embodiment of the present invention, the antiferroelectric material layer with large electrostrain is made of (Pb 1-m- 1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic material, the antiferroelectric material used in the antiferroelectric material layer with small electro-induced strain is selected from (Pb 1-n-1.5x Ban La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials, (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic material; the value range of x, y, z, m, n, and p is 0.02 to 0.06;

[0009] Note that (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic material antiferroelectric material layer is A layer, using (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic material antiferroelectric material layer is B layer, using (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 The antiferroelectric material layer of the O3 antiferroelectric ceramic material is the C layer, then,

[0010] The multilayer antiferroelectric material layer is an antiferroelectric material layer with a total of 2 layers formed by stacking layer A-layer B, or an antiferroelectric material layer with a total of 2 layers formed by stacking layer B-layer C, or an antiferroelectric material layer with a total of 3 layers formed by stacking layer A-layer A-layer B-layer C-layer, or an antiferroelectric material layer with a total of 5 layers formed by stacking layer A-layer A-layer B-layer C-layer C, or an antiferroelectric material layer with a total of 7 layers formed by stacking layer A-layer A-layer A-layer B-layer C-layer C-layer;

[0011] Alternatively, the multilayer antiferroelectric material layer is formed by periodically stacking layer A-layer B, or by periodically stacking layer B-layer C, or by periodically stacking layer A-layer B-layer C, or by periodically stacking layer A-layer A-layer B-layer C-layer C, or by periodically stacking layer A-layer A-layer A-layer B-layer C-layer C.

[0012] As a further preferred embodiment of the present invention, the thickness of each antiferroelectric material layer itself does not exceed 50 μm.

[0013] As a further preferred embodiment of the present invention, for the electrodes inside the multilayer antiferroelectric material layer, two adjacent electrodes are staggered in the left and right directions to form an interdigitated electrode structure as a whole;

[0014] Antiferroelectric material sacrificial layers are stacked above and below the multi-layer antiferroelectric material layers.

[0015] According to another aspect of the present invention, the present invention provides a method for preparing the above-mentioned antiferroelectric multilayer capacitor having a heterostructure, characterized in that it comprises the following steps:

[0016] S1. Preparing antiferroelectric material powder with large electro-strain and antiferroelectric material powder with small electro-strain, respectively, and tape-casting them to obtain a monolayer film of antiferroelectric material with large electro-strain and a monolayer film of antiferroelectric material with small electro-strain; then, slicing and cutting these monolayer films, and printing metal as an electrode on the upper surface of the cut monolayer film by screen printing;

[0017] Among them, the antiferroelectric material with larger electrostrain is (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic material, the antiferroelectric material with smaller electro-induced strain is selected from (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials, (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic material; the value range of x, y, z, m, n, and p is 0.02 to 0.06;

[0018] S2. stacking the monolayer films with electrodes from bottom to top so that, except for the upper and lower end faces, the upper and lower layers adjacent to each antiferroelectric material monolayer film having a larger electrostrain are both antiferroelectric material monolayer films having a smaller electrostrain, followed by hot pressing to obtain a capacitor green body having a multilayer heterostructure, and then performing cold isostatic pressing;

[0019] S3. The green body after cold isostatic pressing is subjected to debinding treatment to remove organic matter introduced during the casting process, and then sintered. After cooling, silver electrode slurry is applied to the left and right end surfaces, and the end electrodes are prepared by sintering to obtain an antiferroelectric multilayer capacitor with a heterostructure.

[0020] As a further preferred embodiment of the present invention, in step S2, before the hot pressing, it further includes forming antiferroelectric material sacrificial layers above and below the stacked structure;

[0021] In step S3, the sintered end is heated to 600°C at 5°C / min, kept at this temperature for 10-30 minutes, and cooled in the furnace.

[0022] As a further preferred embodiment of the present invention, in step S1, (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic materials are based on (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 is prepared by mixing raw materials of PbO, BaCO3, La2O3, ZrO2 and SnO2 in the nominal chemical dosage ratio of the metal elements, and then performing the first ball milling and the first drying; then pre-calcining, and the second ball milling and the second drying are performed to obtain (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic materials;

[0023] (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials are based on (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 is prepared by mixing raw materials of PbO, BaCO3, La2O3, ZrO2, SnO2 and TiO2 in the nominal chemical dosage ratio of the metal elements in the mixture, and then performing the first ball milling process and the first drying process; then pre-calcining, and performing the second ball milling process and the second drying process to obtain (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials;

[0024] (Pb 1.01-p-1.5z Cap La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic materials are based on (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 The raw materials of PbO, CaCO3, La2O3, ZrO2 and SnO2 are mixed in the nominal chemical dosage ratio of the metal elements in O3, and then subjected to the first ball milling treatment and the first drying; then pre-calcined, and subjected to the second ball milling treatment and the second drying, to obtain (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic material.

[0025] As a further preference of the present invention, for each antiferroelectric ceramic material:

[0026] The ball milling speed of the first ball milling treatment is 200-500 r / min, and the ball milling time is 3-48 h; the drying temperature of the first drying treatment is 50-110° C., and the drying time is 3-12 h;

[0027] The pre-firing temperature is 800-950℃ and the pre-firing time is 2-5h;

[0028] The ball milling speed of the second ball milling treatment is 200-500 r / min, and the ball milling time is 3-48 hours; the drying temperature of the second drying treatment is 50-110° C., and the drying time is 3-12 hours.

[0029] As a further preferred embodiment of the present invention, in step S1, the casting process comprises dispersing the corresponding antiferroelectric ceramic material powder with a dispersant, a defoaming agent, a binder and a plasticizer in a solvent, ball milling and mixing at a speed of 200 to 500 r / min for 3 to 48 hours to obtain a casting slurry, vacuum degassing for 10 to 60 minutes, and casting the casting slurry on a casting machine at a speed of 0.5 to 5 m / min and drying to obtain a single-layer film;

[0030] Preferably, the thickness of the single-layer film obtained by casting is 5 to 50 μm.

[0031] As a further preferred embodiment of the present invention, in step S2, the metal is silver, palladium, copper, nickel, platinum or an alloy of two or more thereof; the thickness of the screen-printed electrode is 0.5 to 3 μm;

[0032] The hot pressing treatment temperature of the hot pressing is 60-80°C, the pressure value is 2-20Mpa, and the holding time is 1-30min;

[0033] The pressure value of cold isostatic pressing treatment is 50~200Mpa, and the holding time is 10~30min;

[0034] In step S3, the debinding treatment is carried out at a temperature of 500 to 600° C. for 30 to 300 minutes;

[0035] The sintering process is carried out at a temperature of 1100 to 1200° C. for 2 to 6 hours.

[0036] The above technical solution conceived by the present invention is compared with the existing technology. Based on the heterostructure design strategy, the present invention selects antiferroelectric materials with different electrostrain properties (wherein the electrostrain S of the antiferroelectric material with larger electrostrain is greater than 0.20%, and the electrostrain S of the antiferroelectric material with smaller electrostrain is less than 0.20%, and the strain difference ΔS is greater than 0.10%) to construct a heterostructure, so that the tensile strain and compressive strain are precisely distributed in the corresponding dielectric layers. The antiferroelectric multilayer capacitor prepared by the present invention has interlayer strain interaction. The in-plane mismatched tensile strain will reduce the domain size and reduce the loss caused by domain reversal, while the in-plane mismatched compressive strain will increase the domain size and improve the polarization strength. It can decouple the inherent conflict between high polarization and low loss (low ΔE), and achieve high energy storage density, high energy storage efficiency and excellent reliability.

[0037] Most of the research in the prior art focuses on optimizing the performance of a single material, while ignoring the strain coordination in the multilayer structure. Taking the lead zirconate-based antiferroelectric ceramic material as an example, the prior art reports a variety of lead zirconate-based antiferroelectric ceramic materials. Based on the present invention, a heterogeneous structure of a multilayer antiferroelectric ceramic material layer can be constructed, which includes an antiferroelectric ceramic material layer with a larger electro-strain and an antiferroelectric ceramic material layer with a smaller electro-strain, according to the different electro-strain sizes of various lead zirconate-based materials. Among them, the antiferroelectric ceramic material layer with a larger electro-strain is made of (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic materials (0.02≤m≤0.06, 0.02≤y≤0.06; such as, (Pb 0.98-1.5y Ba 0.02 La y )(Zr 0.6 Sn 0.4 )O3), the antiferroelectric ceramic material used in the antiferroelectric ceramic material layer with small electro-induced strain is selected from (Pb 1-n-1.5x Ba n Lax )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials (0.02≤n≤0.06, 0.02≤x≤0.06; such as, (Pb 0.96-1.5x Ba 0.04 La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3)、(Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic materials (0.02≤p≤0.06, 0.02≤z≤0.06; such as, (Pb 0.95-1.5z Ca 0.06 La z )(Zr 0.6 Sn 0.4 ) 0.995 O3); and, except for the upper end face and the lower end face, the upper antiferroelectric ceramic material layer and the lower antiferroelectric ceramic material layer adjacent to each antiferroelectric ceramic material layer with larger electrostrain are both antiferroelectric ceramic material layers with smaller electrostrain. A multilayer ceramic capacitor is formed by forming antiferroelectric material layers with different electrostrains, thereby utilizing the antiferroelectric-ferroelectric phase transition characteristics induced by the electric field and the different electrostrain characteristics (that is, by utilizing the in-plane mismatch strain between the dielectric layers during the charging and discharging process to adjust the domain size, domain reversal behavior and polarization characteristics of the antiferroelectric material), thereby significantly improving the energy storage efficiency while maintaining a high energy storage density and improving the reliability of the capacitor.

[0038] The heterostructured multilayer capacitor prepared by the present invention has interlayer strain interaction. During the charge and discharge process, the in-plane mismatch strain between the dielectric layers is used to adjust the domain size, domain reversal behavior and polarization characteristics of the antiferroelectric material, thereby simultaneously improving the energy storage density and energy storage efficiency of the capacitor and extending the service life of the device. This is of great significance for the development of high-performance antiferroelectric multilayer capacitors.

[0039] Taking lead zirconate-based antiferroelectric ceramic materials as an example, unlike the existing technology where single lead zirconate-based materials cannot balance energy storage density and energy storage efficiency, the present invention achieves both by designing a multilayer antiferroelectric material structure with varying electrostrain levels, resulting in a capacitor with both high energy storage density and high energy storage efficiency. Taking Table 1 below as an example, the energy storage density of the device in Example 1 obtained based on the present invention is 20.0 J cm -3, the energy storage efficiency is 95.2%, while Comparative Examples 1, 2, and 3, which use a single material to construct a multilayer antiferroelectric ceramic material layer, either have good energy storage density but unsatisfactory energy storage efficiency, or good energy storage efficiency but unsatisfactory energy storage density, and cannot take both into account. Higher energy storage efficiency also means a decrease in the proportion of Joule heat generated, which reduces the requirements for heat dissipation and is very consistent with the development trend of integration, miniaturization, and lightweighting. Moreover, as shown in Table 1 below, Comparative Examples 1, 2, and 3, which use a single material to construct a multilayer antiferroelectric ceramic material layer, either have a high saturation polarization intensity or a high breakdown electric field intensity, and the two are mutually exclusive and cannot be taken into account; while the device of Example 1 obtained based on the present invention has both high saturation polarization intensity and high breakdown electric field intensity. Of course, in addition to the lead zirconate-based antiferroelectric ceramic material, the present invention can also use other antiferroelectric materials, as long as the electrostrain of each antiferroelectric material layer in the formed multilayer antiferroelectric material layer is large and the electrostrain is small (the electrostrain of the larger one is S>0.20%, the electrostrain of the smaller one is S≤0.20%, and the strain difference ΔS between the two is greater than 0.10%), and the sintering temperature zones of the antiferroelectric materials are compatible so that the multilayer antiferroelectric material layer can be prepared by the same sintering process (for example, (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3、(Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3、(Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 Taking O3 material as an example, the value ranges of x, y, z, m, n, and p are all 0.02 to 0.06, and their sintering temperatures are all between 1200 and 1300°C; of course, if the casting process is used first and then sintering is performed, the sintering temperature can be lowered, for example, a sintering temperature of 1100 to 1200°C can be used).

[0040] In addition, the method of the present invention has a simple preparation process and good production process compatibility, which is conducive to industrial batch production.

[0041] In summary, the present invention constructs an antiferroelectric multilayer capacitor with a heterogeneous structure, and the obtained device has the characteristics of high energy storage density and high energy storage efficiency. Taking the use of lead zirconate-based antiferroelectric ceramic materials as an example, it effectively solves the problems of high energy storage density and high energy storage efficiency being difficult to achieve and poor reliability in lead zirconate-based antiferroelectric multilayer ceramic capacitors under the existing technology, provides a new design and preparation idea for the research and development of antiferroelectric multilayer ceramic capacitors with high energy storage density, high energy storage efficiency and excellent reliability, promotes the practical application of lead zirconate-based antiferroelectric ceramic materials, and helps to promote the development of electronic components towards integration, miniaturization and lightweight. BRIEF DESCRIPTION OF THE DRAWINGS

[0042] Figure 1 This is a schematic diagram of the structure of a single antiferroelectric multilayer ceramic capacitor prepared in Comparative Example 1 of the present invention. Comparative Examples 2 and 3 also use this structure, only needing to replace "medium A" with the corresponding dielectric material (in this invention, (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 material is recorded as A, and (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 material is marked as B, (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 material is recorded as C).

[0043] Figure 2 Schematic diagram of the structure of the heterostructure antiferroelectric multilayer ceramic capacitor prepared in Examples 1 and 3 of the present invention.

[0044] Figure 3 Schematic diagram of the structure of the heterostructure antiferroelectric multilayer ceramic capacitor prepared in Examples 2 and 4 of the present invention.

[0045] Figure 4 These are cross-sectional scanning electron microscope (SEM) images of the PB4L4ZST antiferroelectric multilayer ceramic capacitor prepared in comparative example 1 of the present invention, the PB2L2ZS antiferroelectric multilayer ceramic capacitor prepared in comparative example 2, the PC6L2ZS antiferroelectric multilayer ceramic capacitor prepared in comparative example 3, and the heterostructure antiferroelectric multilayer ceramic capacitor prepared in Example 1 after sintering.

[0046] Figure 5The energy storage density and energy storage efficiency of the PB4L4ZST antiferroelectric multilayer ceramic capacitor prepared in Comparative Example 1, the PB2L2ZS antiferroelectric multilayer ceramic capacitor prepared in Comparative Example 2, the PC6L2ZS antiferroelectric multilayer ceramic capacitor prepared in Comparative Example 3, and the heterostructure antiferroelectric multilayer ceramic capacitor prepared in Example 1 under maximum electric field are shown in the figure. The specific values ​​(unit: kV cm -1 ) is the corresponding breakdown electric field strength.

[0047] Figure 6 This is a cyclic stability graph of the energy storage density and energy storage efficiency of the heterostructure antiferroelectric multilayer ceramic capacitor prepared in Example 1 of the present invention.

[0048] Figure 7 The capacitors prepared in Comparative Example 1, Comparative Example 2 and Comparative Example 3 are 350 kV cm -1 Electrostrain curves obtained by electrostrain testing under electric field strength conditions (i.e., electrostrain curves of the three antiferroelectric materials PB4L4ZST, PB2L2ZS, and PC6L2ZS). DETAILED DESCRIPTION

[0049] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the present invention is further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely for the purpose of explaining the present invention and are not intended to limit the present invention. In addition, the technical features involved in the various embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.

[0050] In the following examples, unless otherwise specified, all reagents used were commercially available reagents; all detection means and methods used were conventional detection means and methods in the art. The quantitative tests in the following examples were all repeated three times, and the data are the average or mean ± standard deviation of the three repeated experiments.

[0051] The embodiments below focus on the multiple layers of antiferroelectric material layers (i.e., active layers, antiferroelectric material layers printed with electrodes) in antiferroelectric multilayer capacitors. Similar to conventional operations, antiferroelectric material sacrificial layers (i.e., antiferroelectric material layers without printed electrodes, used to protect the middle active layer and prevent sintering and bending; the antiferroelectric material used in the sacrificial layer is the same as the antiferroelectric material system used in the active layer, i.e., a lead zirconate-based system) can be stacked above and below the multiple layers of antiferroelectric material layers. In other words, the middle part of the device is the active layer, and the upper and lower parts are sacrificial layers; for the active layer, electrodes are provided on the upper and lower surfaces of each active layer, the upper and lower surfaces of the middle layer share electrodes with the adjacent layers, and a separate electrode is provided on the upper surface of the uppermost layer and the lower surface of the lowermost layer of the active layer; the sacrificial layers on the upper and lower sides are stacked by antiferroelectric film strips without printed electrodes.

[0052] Comparative Example 1

[0053] This comparative example is prepared with reference to the prior art (Pb 0.9 Ba 0.04 La 0.04 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 (abbreviated as PB4L4ZST) antiferroelectric ceramic material, and further preparing PB4L4ZST antiferroelectric multilayer ceramic capacitors. Specifically comprising the following steps:

[0054] (1) According to the chemical formula (Pb 0.9 Ba 0.04 La 0.04 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3, weigh the raw materials PbO, BaCO3, La2O3, ZrO2, SnO2 and TiO2, ball mill them at a speed of 400 r / min for 6 h, and then dry them at a temperature of 80°C for 6 h to obtain a mixed powder;

[0055] (2) The PB4L4ZST mixed powder was pre-calcined at 850°C for 3 h and subjected to a secondary ball milling treatment at a ball milling speed of 400 r / min for 6 h, followed by drying at a drying temperature of 80°C for 6 h;

[0056] (3) The PB4L4ZST pre-calcined powder was mixed with a dispersant, a defoaming agent, a binder, a plasticizer and a solvent by ball milling at a speed of 400 r / min for 6 h to obtain a casting slurry (the formula of the casting slurry can be set with reference to the relevant prior art. In each comparative example and embodiment of the present invention, including this example, the solvent is a mixed solution of anhydrous ethanol and toluene, which is used to dissolve the added organic matter; the binder is a mixed solution of polyvinyl butyral and ethanol, which is used to wrap the ceramic powder particles and form a three-dimensional resin frame after curing, so that the casting film has a certain degree of flexibility; the defoaming agent is a three-dimensional resin frame). Oleic acid glycerol is used to eliminate some bubbles generated during the stirring process; the dispersant is polyethylene glycol, which is used to disperse the ceramic particles to facilitate the wrapping of the binder; the plasticizer is butyl benzyl phthalate, which is used to improve the flexibility and ductility of the cast film tape for processing and storage; the pre-calcined and ball-milled powder can be mixed with the above-mentioned organic matter in a certain proportion by ball milling to obtain a mixed solution, and vacuum degassing is carried out for 30 minutes. The cast slurry is cast on a casting machine at a speed of 1m / min and dried to obtain a cast film with a thickness of 20μm, forming a PB4L4ZST antiferroelectric single-layer thick film;

[0057] (4) Slicing the PB4L4ZST antiferroelectric single-layer thick film, and printing 70Ag / 30Pd alloy as an inner electrode layer on the upper surface of the cut thick film by screen printing (of course, in addition to the commonly used 70Ag / 30Pd, other common metal electrode materials such as silver, palladium, copper, nickel, platinum or their alloys can also be used), with a thickness of 1 μm;

[0058] (5) The PB4L4ZST antiferroelectric single-layer thick film with electrodes was staggered to form an interdigitated electrode structure, and then hot pressed at a temperature of 70°C, a pressure of 5 MPa, and a holding time of 10 min; the cold isostatic pressing pressure was 100 MPa and the holding time was 20 min to obtain an antiferroelectric multilayer ceramic capacitor green body with a single structure;

[0059] (6) The green body after cold isostatic pressing is placed in a muffle furnace, debinded at 600°C for 120 minutes (debinding is to volatilize the organic matter introduced by the casting operation, thereby facilitating the dense growth of the ceramic in the subsequent sintering process), sintered at 1120-1150°C for 300 minutes, and taken out after naturally cooling to room temperature. Silver paste is applied to both ends as terminal electrodes, and silver is burned (i.e., silver electrode paste is applied to both ends of the sintered multilayer ceramic capacitor, and the end is burned. The process is: heating to 600°C at 5°C / min, keeping warm for 10-20 minutes, and cooling with the furnace; the same below). The PB4L4ZST antiferroelectric multilayer ceramic capacitor (structure as shown) is obtained. Figure 1 shown).

[0060] Comparative Example 2

[0061] This comparative example is prepared with reference to the prior art (Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3 (abbreviated as PB2L2ZS) antiferroelectric ceramic material, and further preparing a PB2L2ZS antiferroelectric multilayer ceramic capacitor. Specifically comprising the following steps:

[0062] (1) According to the chemical formula (Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3, weigh the raw materials PbO, BaCO3, La2O3, ZrO2 and SnO2, ball mill them at a speed of 400 r / min for 6 h, and then dry them at a temperature of 80°C for 6 h to obtain a mixed powder;

[0063] (2) The PB2L2ZS mixed powder was pre-calcined at 900°C for 3 h and subjected to a secondary ball milling treatment at a ball milling speed of 400 r / min for 6 h, followed by drying at a drying temperature of 80°C for 6 h;

[0064] (3) The PB2L2ZS pre-calcined powder was mixed with a dispersant, a defoaming agent, a binder, a plasticizer and a solvent by ball milling at a speed of 400 r / min for 6 h to obtain a casting slurry, and the foaming was removed by vacuum for 30 min. The casting slurry was cast on a casting machine at a speed of 1 m / min and dried to obtain a casting film with a thickness of 20 μm, thereby forming a PB2L2ZS antiferroelectric single-layer thick film;

[0065] (4) Slicing the PB2L2ZS antiferroelectric single-layer thick film, and printing 70Ag / 30Pd alloy as an inner electrode layer on the surface of the cut thick film by screen printing, with a thickness of 1 μm;

[0066] (5) The PB2L2ZS antiferroelectric single-layer thick film with electrodes was staggered to form an interdigitated electrode structure, and then hot pressed at a temperature of 70°C, a pressure of 5 MPa, and a holding time of 10 min; the cold isostatic pressing pressure was 100 MPa and the holding time was 20 min to obtain an antiferroelectric multilayer ceramic capacitor green body with a single structure;

[0067] (6) The green body after cold isostatic pressing is placed in a muffle furnace, debinded at 600°C for 120 minutes, sintered at 1120-1150°C for 300 minutes, and taken out after naturally cooling to room temperature. Silver paste is applied to both ends as terminal electrodes, and silver is burned to obtain the PB2L2ZS antiferroelectric multilayer ceramic capacitor (structure as shown in FIG). Figure 1 shown).

[0068] Comparative Example 3

[0069] This comparative example is prepared with reference to the prior art (Pb 0.92 Ca 0.06 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995 O3 (abbreviated as PC6L2ZS) antiferroelectric ceramic material, and further preparing PC6L2ZS antiferroelectric multilayer ceramic capacitors. Specifically comprising the following steps:

[0070] (1) According to the chemical formula (Pb 0.92 Ca 0.06 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995 The raw materials PbO, CaCO3, La2O3, ZrO2 and SnO2 were weighed according to the stoichiometric ratio of each element in O3, and ball milled at a speed of 400 r / min for 6 h, and then dried at a drying temperature of 80 ° C for 6 h to obtain a mixed powder;

[0071] (2) The PC6L2ZS mixed powder was pre-calcined at 900°C for 3 h and subjected to a secondary ball milling treatment at a ball milling speed of 400 r / min for 6 h, followed by drying at a drying temperature of 80°C for 6 h;

[0072] (3) The PC6L2ZS pre-calcined powder was mixed with a dispersant, a defoaming agent, a binder, a plasticizer, and a solvent by ball milling at a speed of 400 r / min for 6 h to obtain a casting slurry, and the foaming was removed by vacuum for 30 min. The casting slurry was cast on a casting machine at a speed of 1 m / min and dried to obtain a casting film with a thickness of 20 μm, thereby forming a PC6L2ZS antiferroelectric single-layer thick film;

[0073] (4) Slicing the PC6L2ZS antiferroelectric single-layer thick film, and printing 70Ag / 30Pd alloy as an inner electrode layer on the surface of the cut thick film by screen printing, with a thickness of 1 μm;

[0074] (5) The PC6L2ZS antiferroelectric single-layer thick film with electrodes was staggered to form an interdigitated electrode structure, and then hot pressed at a temperature of 70°C, a pressure of 5 MPa, and a holding time of 10 min; the cold isostatic pressing was performed at a pressure of 100 MPa and a holding time of 20 min to obtain an antiferroelectric multilayer ceramic capacitor green body with a single structure;

[0075] (6) The green body after cold isostatic pressing is placed in a muffle furnace, debinded at 600°C for 120 minutes, sintered at 1120-1150°C for 300 minutes, and taken out after naturally cooling to room temperature. Silver paste is applied to both ends as terminal electrodes, and silver is burned to obtain the PC6L2ZS antiferroelectric multilayer ceramic capacitor (structure as shown in FIG. Figure 1 shown).

[0076] Example 1

[0077] This embodiment provides a heterostructure with an "ABC" periodic cycle (the period is 2) (Pb 0.9 Ba 0.04 La 0.04 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3-(Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3-(Pb 0.92 Ca 0.06 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995 O3 (abbreviated as PB4L4ZST-PB2L2ZS-PC6L2ZS) antiferroelectric multilayer ceramic capacitor and its preparation method. Specifically comprising the following steps:

[0078] (1) Prepare (Pb 0.9 Ba 0.04 La 0.04 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3、(Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3, and (Pb 0.92 Ca 0.06 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995O3 antiferroelectric powder, and the preparation method is consistent with the method in step (1) of Comparative Examples 1, 2 and 3 respectively;

[0079] (2) PB4L4ZST, PB2L2ZS and PC6L2ZS powders were pre-calcined and ball-milled for a second time, and then dried. The specific methods were consistent with those in step (2) of Comparative Examples 1, 2 and 3, respectively;

[0080] (3) The PB4L4ZST, PB2L2ZS and PC6L2ZS pre-calcined powders are respectively mixed with a dispersant, a defoaming agent, a binder, a plasticizer and a solvent by ball milling, and then subjected to tape casting treatment. The specific method is consistent with the method in step (3) of comparative examples 1, 2 and 3, respectively, to finally form PB4L4ZST, PB2L2ZS and PC6L2ZS antiferroelectric single-layer thick films;

[0081] (4) Slicing the PB4L4ZST, PB2L2ZS, and PC6L2ZS antiferroelectric single-layer thick films, and printing 70Ag / 30Pd alloy as an inner electrode layer on the surface of the cut thick films by screen printing, with a thickness of 1 μm;

[0082] (5) stacking and hot pressing and cold isostatic pressing of PB4L4ZST, PB2L2ZS and PC6L2ZS antiferroelectric single-layer thick films with electrodes in an "ABC" cycle (the cycle is 2; i.e., ABCABC has a total of 6 layers), and the specific methods are consistent with the methods in step (5) of comparative examples 1, 2 and 3, respectively, to finally obtain an antiferroelectric multilayer ceramic capacitor green body with a heterogeneous structure;

[0083] (6) The green body after cold isostatic pressing is placed in a muffle furnace for debinding and sintering. The specific methods are consistent with the methods in step (6) of comparative examples 1, 2 and 3. After cooling naturally to room temperature, the green body is taken out, silver paste is applied to both ends as terminal electrodes, and silver is burned to obtain the PB4L4ZST-PB2L2ZS-PC6L2ZS antiferroelectric multilayer ceramic capacitor with heterostructure (structure as shown in FIG). Figure 2 shown).

[0084] Example 2

[0085] This embodiment provides a heterostructure with an "AABCC" periodic cycle (the period is 2) (Pb 0.9 Ba 0.04 La 0.04 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3-(Pb 0.9 Ba 0.04 La 0.04 )(Zr 0.65 Sn0.3 Ti 0.05 )O3-(Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3-(Pb 0.92 Ca 0.06 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995 O3-(Pb 0.92 Ca 0.06 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995 O3 (abbreviated as PB4L4ZST-PB4L4ZST-PB2L2ZS-PC6L2ZS-PC6L2ZS) antiferroelectric multilayer ceramic capacitor and its preparation method.

[0086] Compared with Example 1, the present embodiment differs in that: in step (5), the antiferroelectric single-layer thick film with electrodes is stacked in an interlaced manner according to the "AABCC" cycle (the cycle period is 2; that is, AABCCAABCC has a total of 10 layers) to form an interdigitated electrode structure, followed by hot pressing, the hot pressing temperature is 70°C, the pressure value is 5 MPa, and the holding time is 10 minutes; the cold isostatic pressing pressure value is 100 MPa, and the holding time is 20 minutes, to obtain an antiferroelectric multilayer ceramic capacitor green body with a heterogeneous structure; the remaining steps are the same as Example 1. The structure of the PB4L4ZST-PB4L4ZST-PB2L2ZS-PC6L2ZS-PC6L2ZS antiferroelectric multilayer ceramic capacitor is as follows: Figure 3 shown.

[0087] Example 3

[0088] This embodiment provides a heterostructure with an "ABC" periodic cycle (the period is 2) (Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3-(Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3-(Pb 0.96 Ca 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )0.995 O3 (abbreviated as PB2L2ZST-PB2L2ZS-PC2L2ZS) antiferroelectric multilayer ceramic capacitor and its preparation method.

[0089] The difference between this embodiment and embodiment 1 is that: step (1) is as follows: 0.95 Ba 0.02 La 0.02 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3、(Pb 0.95 Ba 0.02 La 0.02 )(Zr 0.6 Sn 0.4 )O3 and (Pb 0.96 Ca 0.02 La 0.02 )(Zr 0.6 Sn 0.4 ) 0.995 The stoichiometric ratio of each element in O3 was calculated. The raw materials PbO, BaCO3, CaCO3, La2O3, ZrO2, SnO2 and TiO2 were weighed and mixed in batches by ball milling. The remaining steps were the same as in Example 1. The structure of the PB2L2ZST-PB2L2ZS-PC2L2ZS antiferroelectric multilayer ceramic capacitor is shown in FIG. Figure 2 shown.

[0090] Example 4

[0091] This embodiment provides a heterostructure with an "AABCC" periodic cycle (the period is 2) (Pb 0.85 Ba 0.06 La 0.06 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3-(Pb 0.85 Ba 0.06 La 0.06 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3-(Pb 0.85 Ba 0.06 La 0.06 )(Zr 0.6 Sn 0.4 )O3-(Pb 0.86 Ca 0.06 La 0.06 )(Zr 0.6 Sn 0.4 ) 0.995 O3-(Pb 0.86 Ca 0.06La 0.06 )(Zr 0.6 Sn 0.4 ) 0.995 O3 (abbreviated as PB6L6ZST-PB6L6ZST-PB6L6ZS-PC6L6ZS-PC6L6ZS) antiferroelectric multilayer ceramic capacitor and its preparation method.

[0092] The difference between this embodiment and embodiment 2 is that: step (1) is as follows: 0.85 Ba 0.06 La 0.06 )(Zr 0.65 Sn 0.3 Ti 0.05 )O3、(Pb 0.85 Ba 0.06 La 0.06 )(Zr 0.6 Sn 0.4 )O3 and (Pb 0.86 Ca 0.06 La 0.06 )(Zr 0.6 Sn 0.4 ) 0.995 The stoichiometric ratio of each element in O3 was calculated. The raw materials PbO, BaCO3, CaCO3, La2O3, ZrO2, SnO2 and TiO2 were weighed and mixed in batches by ball milling. The remaining steps were the same as those in Example 2. The structure of the PB6L6ZST-PB6L6ZST-PB6L6ZS-PC6L6ZS-PC6L6ZS antiferroelectric multilayer ceramic capacitor is shown in FIG. Figure 3 shown.

[0093] Result analysis:

[0094] The performance of the antiferroelectric multilayer ceramic capacitors prepared in Comparative Examples 1, 2, 3 and Example 1 was tested. The test results are shown in Table 1.

[0095] Table 1: Performance comparison of Comparative Examples 1, 2, 3 and Example 1

[0096]

[0097] It can be seen from the above table that the heterostructure antiferroelectric multilayer ceramic capacitor prepared by the preparation method of the present invention has excellent energy storage performance.

[0098] Figure 4Cross-sectional SEM images of sintered antiferroelectric multilayer ceramic capacitors from Comparative Example 1 (PB4L4ZST), Comparative Example 2 (PB2L2ZS), Comparative Example 3 (PC6L2ZS), and Example 1 (PB4L4ZST-PB2L2ZS-PC6L2ZS) are shown. The images demonstrate the dense ceramic microstructure and a clear metal electrode-ceramic interface.

[0099] Figure 5 The energy storage density and energy storage efficiency of the antiferroelectric multilayer ceramic capacitors of Comparative Example 1, Comparative Example 2, Comparative Example 3 and Example 1 under the maximum electric field are shown in the figure. It can be seen from the figure that Comparative Example 1 has a lower energy storage density (10.5 J cm -3 ), comparative example 2 has a lower energy storage efficiency (82.2%), comparative example 3 has a lower energy storage efficiency (84.1%), while the heterostructured PB4L4ZST-PB2L2ZS-PC6L2ZS antiferroelectric multilayer ceramic capacitor has a high energy storage density (20.0 J cm -3 ) and high energy storage efficiency (95.2%).

[0100] Figure 6 This is a cyclic stability diagram of the energy storage density and energy storage efficiency of the heterostructure antiferroelectric multilayer ceramic capacitor prepared in Example 1 of the present invention. As can be seen from the figure, Example 1 has a high energy storage capacity of 500 kV cm -1 Under an external electric field, after 100,000 cycles of charge and discharge, the energy storage density changes within a range of <4%, and the energy storage efficiency remains at 94%, indicating that Example 1 has excellent cycle stability and is beneficial for practical applications.

[0101] Figure 7 The electrostrain curves for the antiferroelectric multilayer ceramic capacitors obtained in Comparative Examples 1, 2, and 3 show that the electrostrains of PB4L4ZST, PB2L2ZS, and PC6L2ZS are 0.16%, 0.27%, and 0.10%, respectively. PB4L4ZST and PC6L2ZS exhibit low electrostrain, while PB2L2ZS exhibits high electrostrain. Furthermore, the differences in electrostrain are all greater than 0.10%.

[0102] The above embodiments are merely examples. As long as the upper antiferroelectric ceramic material layer and / or the lower antiferroelectric ceramic material layer adjacent to each antiferroelectric ceramic material layer with a larger electro-strain (corresponding to material B) are antiferroelectric ceramic material layers with a smaller electro-strain (e.g., material A, material C), it will suffice. For example, except Figure 2 The "ABC" cycle shown, Figure 3In addition to the "AABCC" cycle shown, "AB" cycle, "BC" cycle, etc. can also be used; for example, considering that material A and material C can improve energy storage efficiency, other variations such as "AAABCCC" periodic stacking can be further adopted; the cycle period n can be a positive integer greater than 1; of course, the cycle period can also be omitted (corresponding to cycle period n = 1). In addition, the preparation process of the antiferroelectric powder material, the capacitor end burning process, the material and preparation process of the sacrificial layer, etc. can all be carried out with reference to the existing technology.

[0103] In addition, the above embodiment uses the tape casting method to prepare a thick antiferroelectric ceramic material layer as an example (thickness 1 to 50 μm). If antiferroelectric ceramic material films of different thicknesses are used, they can also obtain antiferroelectric multilayer ceramic capacitors with heterogeneous structures, while improving energy storage density and energy storage efficiency. Moreover, the smaller the film thickness, the greater the breakdown electric field strength, which is conducive to further improving energy storage density. Of course, in addition to antiferroelectric ceramic materials, the present invention can also use other antiferroelectric materials to obtain antiferroelectric multilayer capacitors with heterogeneous structures, as long as the electrostrain of each antiferroelectric material layer in the formed multilayer antiferroelectric material layer is large and the electrostrain is small (the electrostrain of the larger electrostrain layer is S>0.20% and the electrostrain of the smaller electrostrain layer is S≤0.20%, and the strain difference ΔS between the two is>0.10%), and the sintering temperature zones of the antiferroelectric materials are compatible, so that the multilayer antiferroelectric material layer can be prepared by the same sintering process.

[0104] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An antiferroelectric multilayer capacitor having a heterostructure, characterized in that: The invention comprises a plurality of antiferroelectric material layers stacked from bottom to top, wherein electrodes are provided on the upper and lower surfaces of each antiferroelectric material layer, and two adjacent antiferroelectric material layers share a common electrode; The multilayer antiferroelectric material layer is prepared by the same sintering process. According to the electrostrain of each antiferroelectric material layer in the multilayer antiferroelectric material layer, the multilayer antiferroelectric material layer includes both an antiferroelectric material layer with a larger electrostrain and an antiferroelectric material layer with a smaller electrostrain. In addition, in the multilayer antiferroelectric material layer, except for the upper end surface and the lower end surface, the upper antiferroelectric material layer and the lower antiferroelectric material layer adjacent to each antiferroelectric material layer with a larger electrostrain are both antiferroelectric material layers with a smaller electrostrain. Among them, the electrostrain S of the antiferroelectric material layer with larger electrostrain is greater than 0.20%, the electrostrain S of the antiferroelectric material layer with smaller electrostrain is less than or equal to 0.20%, and the electrostrain difference ΔS between the two is greater than 0.10%; the electrostrain S of each antiferroelectric material layer corresponds to the electric field strength corresponding to when the polarization intensity of each antiferroelectric material in the multi-layer antiferroelectric material layer reaches saturation, and the minimum electric field strength is used as the electrostrain test electric field, and each antiferroelectric material layer is subjected to electrostrain testing.

2. The antiferroelectric multilayer capacitor having a heterostructure according to claim 1, wherein: The antiferroelectric material layer with large electro-induced strain is made of (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic material, the antiferroelectric material used in the antiferroelectric material layer with small electro-induced strain is selected from (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials, (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic material; the value range of x, y, z, m, n, and p is 0.02 to 0.06; Note that (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic material antiferroelectric material layer is A layer, using (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic material antiferroelectric material layer is B layer, using (Pb 1.01-p- 1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 The antiferroelectric material layer of the O3 antiferroelectric ceramic material is the C layer, then, The multilayer antiferroelectric material layer is an antiferroelectric material layer with a total of 2 layers formed by stacking layer A-layer B, or an antiferroelectric material layer with a total of 2 layers formed by stacking layer B-layer C, or an antiferroelectric material layer with a total of 3 layers formed by stacking layer A-layer A-layer B-layer C-layer, or an antiferroelectric material layer with a total of 5 layers formed by stacking layer A-layer A-layer B-layer C-layer C, or an antiferroelectric material layer with a total of 7 layers formed by stacking layer A-layer A-layer A-layer B-layer C-layer C-layer; Alternatively, the multilayer antiferroelectric material layer is formed by periodically stacking layer A-layer B, or by periodically stacking layer B-layer C, or by periodically stacking layer A-layer B-layer C, or by periodically stacking layer A-layer A-layer B-layer C-layer C, or by periodically stacking layer A-layer A-layer A-layer B-layer C-layer C.

3. The antiferroelectric multilayer capacitor having a heterostructure according to claim 1, wherein: The thickness of each antiferroelectric material layer itself does not exceed 50 μm.

4. The antiferroelectric multilayer capacitor having a heterostructure according to claim 1, wherein: For the electrodes inside the multilayer antiferroelectric material layer, two adjacent electrodes are staggered in the left and right directions to form an interdigitated electrode structure as a whole; Antiferroelectric material sacrificial layers are stacked above and below the multi-layer antiferroelectric material layers.

5. The method for preparing an antiferroelectric multilayer capacitor having a heterostructure according to any one of claims 1 to 4, characterized in that: The following steps are involved: S1. Preparing antiferroelectric material powder with large electro-strain and antiferroelectric material powder with small electro-strain, respectively, and tape-casting them to obtain a monolayer film of antiferroelectric material with large electro-strain and a monolayer film of antiferroelectric material with small electro-strain; then, slicing and cutting these monolayer films, and printing metal as an electrode on the upper surface of the cut monolayer film by screen printing; Among them, the antiferroelectric material with larger electrostrain is (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic material, the antiferroelectric material with smaller electro-induced strain is selected from (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials, (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic material; the value range of x, y, z, m, n, and p is 0.02 to 0.06; S2. stacking the monolayer films with electrodes from bottom to top so that, except for the upper and lower end faces, the upper and lower layers adjacent to each antiferroelectric material monolayer film having a larger electrostrain are both antiferroelectric material monolayer films having a smaller electrostrain, followed by hot pressing to obtain a capacitor green body having a multilayer heterostructure, and then performing cold isostatic pressing; S3. The green body after cold isostatic pressing is subjected to debinding treatment to remove organic matter introduced during the casting process, and then sintered. After cooling, silver electrode slurry is applied to the left and right end surfaces, and the end electrodes are prepared by sintering to obtain an antiferroelectric multilayer capacitor with a heterostructure.

6. The preparation method according to claim 5, characterized in that: In step S2, before the hot pressing, it also includes forming antiferroelectric material sacrificial layers above and below the stacked structure; In step S3, the sintered end is heated to 600°C at 5°C / min, kept at this temperature for 10-30 minutes, and cooled in the furnace.

7. The preparation method according to claim 5, characterized in that: In step S1, (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic materials are based on (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 is prepared by mixing raw materials of PbO, BaCO3, La2O3, ZrO2 and SnO2 in the nominal chemical dosage ratio of the metal elements, and then performing the first ball milling and the first drying; then pre-calcining, and the second ball milling and the second drying are performed to obtain (Pb 1-m-1.5y Ba m La y )(Zr 0.6 Sn 0.4 )O3 antiferroelectric ceramic materials; (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials are based on (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 is prepared by mixing raw materials of PbO, BaCO3, La2O3, ZrO2, SnO2 and TiO2 in the nominal chemical dosage ratio of the metal elements in the mixture, and then performing the first ball milling process and the first drying process; then pre-calcining, and performing the second ball milling process and the second drying process to obtain (Pb 1-n-1.5x Ba n La x )(Zr 0.65 Sn 0.3 Ti 0.05 )O3 antiferroelectric ceramic materials; (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic materials are based on (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 The raw materials of PbO, CaCO3, La2O3, ZrO2 and SnO2 are mixed in the nominal chemical dosage ratio of the metal elements in O3, and then subjected to the first ball milling treatment and the first drying; then pre-calcined, and subjected to the second ball milling treatment and the second drying, to obtain (Pb 1.01-p-1.5z Ca p La z )(Zr 0.6 Sn 0.4 ) 0.995 O3 antiferroelectric ceramic material.

8. The preparation method according to claim 7, wherein: For each antiferroelectric ceramic material: The ball milling speed of the first ball milling treatment is 200-500 r / min, and the ball milling time is 3-48 h; The drying temperature of the first drying is 50-110°C and the drying time is 3-12 hours; The pre-firing temperature is 800-950℃ and the pre-firing time is 2-5h; The ball milling speed of the second ball milling treatment is 200-500 r / min, and the ball milling time is 3-48 hours; the drying temperature of the second drying treatment is 50-110° C., and the drying time is 3-12 hours.

9. The preparation method according to claim 5, wherein: In step S1, the casting process is to disperse the corresponding antiferroelectric ceramic material powder together with a dispersant, a defoaming agent, a binder and a plasticizer in a solvent, ball milling and mixing at a speed of 200 to 500 r / min for 3 to 48 hours to obtain a casting slurry, vacuum degassing for 10 to 60 minutes, and casting the casting slurry on a casting machine at a speed of 0.5 to 5 m / min and drying to obtain a single-layer film.

10. The preparation method according to claim 9, characterized in that: In step S1 , the thickness of the single-layer film obtained by casting is 5 to 50 μm.

11. The preparation method according to claim 5, characterized in that: In step S2, the metal is silver, palladium, copper, nickel, platinum or an alloy of two or more thereof; the thickness of the screen-printed electrode is 0.5 to 3 μm; The hot pressing treatment temperature of the hot pressing is 60-80°C, the pressure value is 2-20Mpa, and the holding time is 1-30min; The pressure value of cold isostatic pressing treatment is 50~200Mpa, and the holding time is 10~30min; In step S3, the debinding treatment is carried out at a temperature of 500 to 600° C. for 30 to 300 minutes; The sintering process is carried out at a temperature of 1100 to 1200° C. for 2 to 6 hours.

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