Rare earth ion doped barium titanate-based ceramic material and preparation method thereof

Abstract

The invention relates to the technical field of barium titanate-based ceramic preparation, in particular to a rare earth ion doped barium titanate-based ceramic material and a preparation method thereof.High-purity tetragonal-phase barium titanate is prepared through a hydrothermal synthesis process, doped ions comprise two rare earth ion elements including europium and dysprosium, and one or more of sodium, magnesium, bismuth, niobium, cobalt, lanthanum and the like are cooperatively doped; barium titanate powder and ion-doped oxide powder are mixed according to a certain proportion, and the ion-doped barium titanate ceramic is prepared through solid-phase sintering. By adopting the formula and the preparation method disclosed by the invention, a barium titanate-based ceramic capacitor product with excellent dielectric property, high stability and low loss can be obtained, and the preparation method is suitable for preparing a high-temperature and high-performance multilayer ceramic capacitor.

Description

Technical Field

[0001] This invention relates to the technical field of barium titanate-based ceramic preparation, specifically to barium titanate-based ceramic materials doped with rare earth ions and their preparation methods. Background Technology

[0002] Multilayer ceramic capacitors (MLCCs), as indispensable passive components in modern electronic devices, are widely used in communications, computers, consumer electronics, and automotive electronics due to their advantages such as small size, large capacitance, and high reliability. Barium titanate ( Barium titanate, as a classic ferroelectric material, has a high dielectric constant and is one of the main dielectric materials for manufacturing MLCCs. However, pure barium titanate-based ceramics have a low Curie temperature (about 120°C), and their dielectric constant varies greatly with temperature and frequency, making it difficult to meet the requirements of high-temperature, high-stability capacitors.

[0003] Therefore, developing barium titanate-based ceramic materials based on rare earth ion synergistic multi-element co-doping to further meet the needs of high-end MLCC applications has significant practical application value. Summary of the Invention

[0004] Therefore, the purpose of this invention is to provide a rare earth ion-doped barium titanate-based ceramic material and its preparation method, so as to improve the dielectric properties, temperature stability and reliability of the material through the synergistic doping effect of multiple ions, and meet the application requirements of high-end MLCCs.

[0005] The technical solution provided by this invention is: a method for preparing barium titanate-based ceramic materials doped with rare earth ions, comprising:

[0006] Step 1: Using high-purity tetragonal barium titanate powder as the matrix; weigh the barium titanate powder and the oxide powder doped with ions according to the stoichiometric ratio;

[0007] Step 2: The barium titanate powder is mixed and refined with the ion-doped oxide powder, and then dried to obtain powder A;

[0008] Step 3: Add binder and solvent to powder A, then ball mill, dry, granulate, and sieve to obtain powder B;

[0009] Step 4: Compress powder B into tablets;

[0010] Step 5: The shaped powder B is solid-state sintered at high temperature to obtain a dense barium titanate-based ceramic sheet.

[0011] Preferably, the high-purity tetragonal barium titanate powder is prepared by hydrothermal synthesis and comprises:

[0012] (1) Weigh the titanium source and dispersant according to the stoichiometric ratio, add them to the ethanol solution, and stir for a certain period of time;

[0013] (2) Weigh out barium hydroxide octahydrate according to the stoichiometric ratio, add deionized water, and stir for a certain time at a certain temperature;

[0014] (3) Mix the titanium source solution with After mixing the solutions and stirring for a certain period of time, add the mineralizing agent and continue stirring.

[0015] (4) Pour the above solution into a hydrothermal reactor and place it in an oven to heat to a certain temperature and keep it warm for a certain time;

[0016] (5) The synthesized product is separated into solid and liquid phases, and after washing and drying, high-purity tetragonal barium titanate powder is obtained.

[0017] Preferably, the titanium source is one of titanium dioxide, tetrabutyl titanate, and ethyl titanate; the dispersant is one or more of ammonium polyacrylate, polyvinylpyrrolidone, and hexadecyltrimethylammonium bromide.

[0018] The molar ratio of the titanium source to barium hydroxide octahydrate is 1:(1~4), and the volume ratio of the ethanol solution to deionized water is 1:1.

[0019] Preferably, the step of pouring the above solution into a hydrothermal reactor and placing it in an oven to heat to a certain temperature and hold it at that temperature for a certain time includes: using a two-stage process, with the first stage heating temperature at 100℃ and holding for 10~15h, and the second stage heating temperature at 200℃ and holding for 24~48h, to obtain the synthesized product.

[0020] Preferably, the doping ions in step 1 include rare earth elements Eu and Dy, and co-doping elements;

[0021] The co-doping element includes one or more of Na, Mg, Bi, Nb, Co, and La;

[0022] The total amount of the two rare earth elements Eu and Dy accounts for 0.1% to 1% of the molar percentage of the barium titanate powder; the total amount of the co-doping elements accounts for 0.5% to 3% of the molar percentage of the barium titanate powder.

[0023] Preferably, in step 2, the barium titanate powder and the oxide powder doped with ions are mixed and refined using a high-energy ball milling method, wherein the ball milling time is 1-2 hours, the rotation speed is 2500-3000 rpm, and the ball milling medium is anhydrous ethanol.

[0024] Preferably, the adhesive in step 3 is one of gum arabic, polyvinyl alcohol, polyvinyl butyral, polyacrylic acid, and hydroxymethyl cellulose;

[0025] The solvent is one of deionized water and anhydrous ethanol.

[0026] Preferably, the tableting in step 4 includes: using a powder tableting machine to compress the powder into tablets at 15~30MPa to obtain green tablets; and then using a cold isostatic press to densify the green tablets at 100~200MPa for a holding time of 5~20min.

[0027] Preferably, the sintering process in step 5 is as follows: increasing the temperature from room temperature to 600℃ at a rate of 1~2℃ / min and holding for 1~3h, then increasing the temperature to 1050~1250℃ at a rate of 3~5℃ / min and holding for 1~3h.

[0028] The present invention also provides a rare earth ion-doped barium titanate-based ceramic material prepared by the aforementioned preparation method.

[0029] This invention provides a rare-earth ion-doped barium titanate-based ceramic material and its preparation method. Through multi-element synergistic doping, the synergistic control of lattice, defect and domain structure is achieved at the microscopic level, ultimately enabling the material to have high dielectric constant, low loss and excellent stability over a wide temperature range, meeting the needs of high-end MLCC applications and having important practical application value. Attached Figure Description

[0030] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with the invention and, together with the description, serve to explain the principles of the invention.

[0031] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, for those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0032] Figure 1 XRD pattern of barium titanate powder prepared by hydrothermal synthesis according to an embodiment of the present invention;

[0033] Figure 2 SEM images of barium titanate powder prepared by hydrothermal synthesis according to embodiments of the present invention;

[0034] Figure 3 The images are SEM images of the ion-doped barium titanate powders provided in Examples 1-4 of this invention. Detailed Implementation

[0035] The present invention will be further explained below with reference to specific implementation schemes, but this explanation does not limit the scope of the invention.

[0036] To address the issues of low Curie temperature (approximately 120°C) and significant variations in dielectric constant with temperature and frequency in pure barium titanate-based ceramics, which make it difficult to meet the requirements of high-temperature, high-stability capacitors, this embodiment provides a method for preparing rare-earth ion-doped barium titanate ceramics based on synergistic doping technology. This method is applicable to the field of electronic components such as capacitors, particularly in the manufacture of multilayer ceramic capacitors. Specifically, it includes the following:

[0037] Step 1: Using high-purity tetragonal barium titanate powder as the matrix; weigh the barium titanate powder and the oxide powder doped with ions according to the stoichiometric ratio;

[0038] The doping ions include two rare earth elements, Eu and Dy, with a total doping amount accounting for 0.1% to 1% of the molar percentage of barium titanate. Co-doping elements include one or more of Na, Mg, Bi, Nb, Co, and La, with a total doping amount accounting for 0.5% to 3% of the molar percentage of barium titanate. This invention, through the co-doping of Eu, Dy, Bi, and Nb ions, jointly regulates the crystal structure and defect state of barium titanate-based ceramics, thereby effectively improving the Curie temperature and dielectric properties of the material. and Mainly through position A ( The size effect of doped ions, the introduction of internal stress, and The lone pair electron effect enhances lattice rigidity and stabilizes the ferroelectric phase, thereby shifting the Curie temperature to higher temperatures and broadening the dielectric peak to improve temperature stability. B-site ( Doped This reduces dielectric loss by suppressing oxygen vacancy generation and enhancing oxygen octahedral stability, and induces relaxor ferroelectric behavior. The synergistic effect of multivalent ion doping, while suppressing harmful defects and optimizing microstructure, can achieve an increase in Curie temperature and a comprehensive enhancement of dielectric properties, making it more suitable for high-temperature electronic devices such as high-performance multilayer ceramic capacitors.

[0039] In addition, the high-purity tetragonal barium titanate powder prepared by hydrothermal synthesis includes the following steps:

[0040] (1) Weigh the titanium source and dispersant according to the stoichiometric ratio, add them to the ethanol solution, and stir for a certain period of time;

[0041] (2) Weigh out barium hydroxide octahydrate according to the stoichiometric ratio. Add deionized water and stir at a certain temperature for a certain time;

[0042] (3) Mix the titanium source solution with After mixing the solutions and stirring for a certain period of time, add 142 mL / L ammonia water as a mineralizing agent and continue stirring.

[0043] (4) Pour the above solution into a hydrothermal reactor and place it in an oven to heat to a certain temperature and keep it warm for a certain time;

[0044] (5) The synthesized product is separated into solid and liquid phases, and after washing and drying, high-purity tetragonal barium titanate powder is obtained.

[0045] like Figure 1 As shown, the diffraction peaks marked with 2θ in the spectrum at 22°, 32°, 40°, and 47° all correspond to... Characteristic crystal planes such as (110), (111), and (200) are observed. Peak position comparison reveals that the positions of these peaks correspond to the standard perovskite structure. The XRD characteristic peaks are in perfect agreement; the absence of extra impurity peaks in the spectrum indicates that the sample is a single pure phase. .

[0046] like Figure 2 As shown in the figure, the left figure shows that the prepared powder particles are widely distributed and have good overall dispersion; the right figure shows that the particles have a spherical / near-polyhedral morphology, with regular and uniform morphology and a size concentrated in 100-200nm, without serious agglomeration, which reflects the characteristics of controllable morphology and good dispersibility of the powder prepared by this process.

[0047] More preferably, the titanium source in step (1) is titanium dioxide (TiO2). ), tetrabutyl titanate ( ), ethyl titanate ( One of them;

[0048] Preferably, the dispersant in step (1) is one or more of ammonium polyacrylate, polyvinylpyrrolidone, and hexadecyltrimethylammonium bromide;

[0049] Preferably, the molar ratio of titanium to barium in steps (1) and (2) is 1:(1~4), and the volume ratio of alcohol to water is 1:1;

[0050] Preferably, the stirring time in steps (1), (2), and (3) is 10 to 30 minutes;

[0051] Preferably, the stirring temperature in step (2) is 40~80℃;

[0052] Preferably, the stirring time after adding the mineralizer in step (3) is 5~15 min;

[0053] Preferably, the heating process in step (4) is a two-stage process, with the first stage heating temperature at 100℃ and holding for 10~15h, and the second stage heating temperature at 200℃ and holding for 24~48h.

[0054] Preferably, the detergent in step (5) consists of deionized water, acetic acid, N,N-dimethylformamide, and anhydrous ethanol in sequence.

[0055] This invention utilizes a simple hydrothermal synthesis process to prepare high-purity barium titanate matrix materials with controllable dimensions and uniform structure.

[0056] Step 2: Mix and refine the powder using high-energy ball milling technology, and then dry it to obtain powder A;

[0057] Preferably, the high-energy ball milling time is 1~2 hours, the rotation speed is 2500-3000 rpm, the ball milling medium is anhydrous ethanol, and the drying temperature is 80~110℃;

[0058] Step 3: Add binder and solvent to powder A, then ball mill, dry, granulate, and sieve to obtain powder B;

[0059] Preferably, the adhesive is one of gum arabic, polyvinyl alcohol (PVA), polyvinyl butyral (PVB), polyacrylic acid (PAA), and carboxymethyl cellulose (CMC);

[0060] Preferably, the solvent is one of deionized water and anhydrous ethanol;

[0061] Preferably, the ball milling time is 0.5~2h, the rotation speed is 300~500rpm, and the sieve size is 60~150 mesh;

[0062] Step 4: Press powder B into tablets to obtain a green body, preferably with a thickness of about 1.5 mm and a diameter of 12 mm;

[0063] Preferably, the tableting process is divided into two parts: the powder is compressed into tablets using a powder tableting machine at 15-30 MPa, and then the green tablets are densified using a cold isostatic press at 100-200 MPa for a holding time of 5-20 minutes.

[0064] Step 5: The shaped powder B is solid-state sintered at high temperature to obtain a dense barium titanate-based ceramic sheet.

[0065] Preferably, the sintering process is as follows: heating from room temperature to 600°C at a rate of 1~2°C / min, holding for 1~3 hours, and heating to 1050~1250°C at a rate of 3~5°C / min, holding for 1~3 hours.

[0066] The preparation process of ion-doped barium titanate-based ceramics provided by this invention is simple, has good repeatability, and is suitable for large-scale production; the dielectric constant of the obtained ion-doped barium titanate-based ceramics can reach 2000-4000, and the Curie temperature is higher than 150℃, meeting the requirements for high-temperature and high-stability MLCCs.

[0067] Example 1:

[0068] Matrix powder preparation: using anatase phase As a titanium source, Using barium as the source, with an alcohol-to-water ratio of 1:1 and a barium-to-titanium molar ratio of 3:1, 1 mmol / L CTAB and 50 g / L PVP were added as dispersants; high-purity tetragonal phase was synthesized via a two-step hydrothermal method. The powder was subjected to hydrothermal treatment at 100℃ for 12 hours, followed by heating to 200℃ and holding for 36 hours. After washing and drying, a matrix powder with a particle size <150 nm was obtained. Figure 1 The image shown is the XRD pattern of barium titanate powder;

[0069] Doping and mixing: Weigh out the matrix powder separately. 450 g of powder, add 0.2 mol% 0.2 mol% 1 mol% After mixing with an appropriate amount of anhydrous ethanol, the mixture is placed in a high-energy ball mill, and the total slurry volume is controlled to not exceed 2 / 3 of the ball mill jar volume. The mixture is ball-milled at 3000 rpm for 1.5 h, and the ball-milled slurry is dried overnight at 100℃.

[0070] Granulation and molding: Take the dried powder and add 5 wt% of 10% gum arabic and deionized water at a water-to-powder ratio of 1:1. Place the mixture in a ball mill and mix at 350 rpm for 0.5 h. Dry again. Grind using a mortar and pestle and pass through a 60-mesh sieve. Take 1 g of powder and press it into shape in a 12 mm mold at a molding pressure of 20 MPa. Then, cold isostatic pressing is applied to obtain a green body at a pressure of 120 MPa for 5 min.

[0071] Sintering and processing: The green body is heated to 600℃ at 2℃ / min and held for 2 h to remove the binder; then heated to 1150℃ at 3℃ / min and held for 2 h; the sintered ceramic sheet is polished, coated with silver paste, dried, and then heated to 550℃ at 2℃ / min and held for 1 h to prepare ceramic electrode sheet.

[0072] Dielectric performance test: The dielectric performance of the ceramic electrode sheet was tested at room temperature under 1MHz power. The results are shown in Table 1.

[0073] Example 2:

[0074] Matrix powder preparation: using tetrabutyl titanate ( (The titanium source is) Using barium as the source, with an alcohol-to-water ratio of 1:1 and a barium-to-titanium molar ratio of 3:1, 1 mmol / L CTAB and 50 g / L PVP were added as dispersants; high-purity tetragonal phase was synthesized via a two-step hydrothermal method. The powder was subjected to hydrothermal treatment at 100℃ for 12 h, followed by heating to 200℃ and holding for 36 h. After washing and drying, a matrix powder with a particle size of <150 nm was obtained.

[0075] Doping and mixing: Weighing 450 g of powder, add 0.1 mol% 0.2 mol% 0.75 mol% 2.0 mol% After mixing with an appropriate amount of anhydrous ethanol, the mixture is placed in a high-energy ball mill, and the total slurry volume is controlled to not exceed 2 / 3 of the ball mill jar volume. The mixture is ball-milled at 2500 rpm for 1.5 h, and the ball-milled slurry is dried overnight at 100℃.

[0076] Granulation and molding: Take the dried powder, add 5 wt% of 10% gum arabic and deionized water (water-to-powder ratio 1:1), and ball mill the mixture at 350 rpm for 1 hour. Dry again; grind using a mortar and pestle, and pass through a 60-mesh sieve. Take 1 g of powder and press it into shape in a 12 mm mold at a molding pressure of 20 MPa. Then, cold isostatic pressing is applied to obtain a green body at a pressure of 120 MPa for 5 minutes.

[0077] Sintering and processing: The green body is heated to 600℃ at 2℃ / min and held for 2 h to remove the binder; then it is heated to 1200℃ at 3℃ / min and held for 2 h; the sintered ceramic sheet is polished, coated with silver paste, dried, and then heated to 560℃ at 2℃ / min and held for 2 h to prepare ceramic electrode sheet.

[0078] Dielectric performance test: The dielectric performance of the ceramic electrode sheet was tested at room temperature under 1MHz power. The results are shown in Table 1.

[0079] Example 3:

[0080] Matrix powder preparation: using tetrabutyl titanate ( (The titanium source is) Using barium as the source, with an alcohol-to-water ratio of 1:1 and a barium-to-titanium molar ratio of 2:1, 1 mmol / L CTAB and 50 g / L PVP were added as dispersants; high-purity tetragonal phase was synthesized via a two-step hydrothermal method. The powder was subjected to hydrothermal treatment at 100℃ for 12 h, followed by heating to 200℃ and holding for 36 h. After washing and drying, a matrix powder with a particle size of <150 nm was obtained.

[0081] Doping and mixing: Weighing 450 g of powder, add 0.5 mol% 0.1 mol% 0.5 mol% and 2.0 mol% After mixing with an appropriate amount of anhydrous ethanol, the mixture is placed in a high-energy ball mill, and the total slurry volume is controlled to not exceed 2 / 3 of the ball mill jar volume. The mixture is ball-milled at 3000 rpm for 2 hours, and the ball-milled slurry is dried overnight at 100℃.

[0082] Granulation and molding: Take the dried powder, add 5 wt% of 10% gum arabic and deionized water (water-to-powder ratio 1:1), and ball mill the mixture at 450 rpm for 1 hour. Dry again; grind using a mortar and pestle, and pass through a 60-mesh sieve. Take 1 g of powder and press it into shape in a 12 mm mold at a molding pressure of 20 MPa. Then, cold isostatic pressing is used to obtain a green body at a pressure of 120 MPa for 5 minutes.

[0083] Sintering and processing: The green body is heated to 600℃ at 2℃ / min and held for 2 h to remove the binder; then heated to 1200℃ at 3℃ / min and held for 2 h; the sintered ceramic sheet is polished, coated with silver paste, dried, and then heated to 580℃ at 2℃ / min and held for 2 h to prepare ceramic electrode sheet.

[0084] Dielectric performance test: The dielectric performance of the ceramic electrode sheet was tested at room temperature under 1MHz power. The results are shown in Table 1.

[0085] Example 4:

[0086] Matrix powder preparation: using ethyl titanate ( (The titanium source is) Using barium as the source, with an alcohol-to-water ratio of 1:1 and a barium-to-titanium molar ratio of 4:1, 1 mmol / L LCTAB and 50 g / L PVP were added as dispersants; high-purity tetragonal phase was synthesized via a two-step hydrothermal method. The powder was subjected to hydrothermal treatment at 100℃ for 12 h, followed by heating to 200℃ and holding for 36 h. After washing and drying, a matrix powder with a particle size of <150 nm was obtained.

[0087] Doping and mixing: Weighing 450 g of powder, add 0.5 mol% 0.5 mol% 0.5 mol% and 2.0 mol% After mixing with an appropriate amount of anhydrous ethanol, the mixture is placed in a high-energy ball mill, and the total slurry volume is controlled to not exceed 2 / 3 of the ball mill jar volume. The mixture is ball-milled at 3000 rpm for 2 hours, and the ball-milled slurry is dried overnight at 100℃.

[0088] Granulation and molding: Take the dried powder, add 5 wt% of 10% gum arabic and deionized water (water-to-powder ratio 1:1), and ball mill the mixture at 500 rpm for 1 hour. Then dry again. Grind the mixture in a mortar and pestle and pass it through a 60-mesh sieve. Take 1 g of powder and press it into shape in a 12 mm mold at a molding pressure of 20 MPa. Then, cold isostatic pressing is applied to obtain a green body at a pressure of 200 MPa for 5 minutes.

[0089] Sintering and processing: The green body is heated to 600℃ at 2℃ / min and held for 2 h to remove the binder; then heated to 1200℃ at 3℃ / min and held for 2 h; the sintered ceramic sheet is polished, coated with silver paste, dried, and then heated to 600℃ at 2℃ / min and held for 2 h to prepare ceramic electrode sheet.

[0090] Dielectric performance test: The dielectric performance of the ceramic electrode sheet was tested at room temperature under 1MHz power. The results are shown in Table 1.

[0091] like Figure 3 As shown in the SEM images of the ion-doped barium titanate powders prepared in Examples 1-4, the powder particles are mainly spherical / near-polyhedral in shape, with nanoscale size and relatively regular morphology. After ball milling, the particles did not show obvious breakage, but a small amount of small particle agglomeration was present. Under different doping elements, the particle size and local agglomeration degree were slightly different, but the overall powder morphology was still good.

[0092] Comparative Example 1:

[0093] The preparation and performance testing process of barium titanate ceramics without ions is used as a comparison with the performance of ceramics with ions.

[0094] Matrix powder preparation: using anatase phase As a titanium source, Using barium as the source, with an alcohol-to-water ratio of 1:1 and a barium-to-titanium molar ratio of 3:1, and with appropriate amounts of CTAB and PVP added as dispersants, high-purity tetragonal phase was synthesized via a two-step hydrothermal method. The powder was subjected to hydrothermal treatment at 100℃ for 12 h, followed by heating to 200℃ and holding for 36 h. After washing and drying, a matrix powder with a particle size of <150 nm was obtained.

[0095] Granulation and molding: Take the dried powder and add 5 wt% of 10% gum arabic and deionized water at a water-to-powder ratio of 1:1. Place the mixture in a ball mill and mix at 350 rpm for 0.5 h. Dry again. Grind using a mortar and pestle and pass through a 60-mesh sieve. Take 1 g of powder and press it into shape in a 12 mm mold at a molding pressure of 20 MPa. Then, cold isostatic pressing is applied to obtain a green body at a pressure of 120 MPa for 5 min.

[0096] Sintering and processing: The green body is heated to 600℃ at 2℃ / min and held for 2 h to remove the binder; then heated to 1200℃ at 3℃ / min and held for 2 h; the sintered ceramic sheet is polished, coated with silver paste, dried, and then heated to 550℃ at 2℃ / min and held for 1 h to prepare ceramic electrode sheet.

[0097] Dielectric performance test: The dielectric performance of the ceramic electrode sheet was tested at room temperature under 1MHz power. The results are shown in Table 1.

[0098] Table 1. Dielectric constants (1MHz) of barium titanate-based ceramic materials co-doped with Eu and Dy ions.

[0099]

[0100] Although preferred embodiments of this application have been described, those skilled in the art, upon learning the basic inventive concept, can make other changes and modifications to these embodiments. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments as well as all changes and modifications falling within the scope of this application.

[0101] Obviously, those skilled in the art can make various modifications and variations to this application without departing from the spirit and scope of this application. Therefore, if such modifications and variations fall within the scope of the claims of this application and their equivalents, this application also intends to include such modifications and variations.

Claims

1. A method for preparing barium titanate-based ceramic materials doped with rare earth ions, characterized in that, include: Step 1: Use high-purity tetragonal barium titanate powder as the matrix; Weigh the barium titanate powder and the oxide powder doped with ions according to the stoichiometric ratio. Step 2: The barium titanate powder is mixed and refined with the ion-doped oxide powder, and then dried to obtain powder A; Step 3: Add binder and solvent to powder A, then ball mill, dry, granulate, and sieve to obtain powder B; Step 4: Compress powder B into tablets; Step 5: The formed powder B is sintered in a solid state at a high temperature to obtain a dense barium titanate-based ceramic sheet.

2. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 1, characterized in that, The high-purity tetragonal barium titanate powder is prepared by hydrothermal synthesis and includes: (1) Weigh the titanium source and dispersant according to the stoichiometric ratio, add them to the ethanol solution, and stir for a certain period of time; (2) Weigh out barium hydroxide octahydrate according to the stoichiometric ratio, add deionized water, and stir for a certain time at a certain temperature; (3) Mix the titanium source solution with After mixing the solutions and stirring for a certain period of time, add the mineralizing agent and continue stirring. (4) Pour the above solution into a hydrothermal reactor and place it in an oven to heat to a certain temperature and keep it warm for a certain time; (5) The synthesized product is separated into solid and liquid phases, and after washing and drying, high-purity tetragonal barium titanate powder is obtained.

3. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 2, characterized in that, The titanium source is one of titanium dioxide, tetrabutyl titanate, and ethyl titanate; the dispersant is one or more of ammonium polyacrylate, polyvinylpyrrolidone, and hexadecyltrimethylammonium bromide. The molar ratio of the titanium source to barium hydroxide octahydrate is 1:(1~4), and the volume ratio of the ethanol solution to deionized water is 1:

1.

4. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 2, characterized in that, The step of pouring the above solution into a hydrothermal reactor and placing it in an oven to heat to a certain temperature and hold it at that temperature for a certain time includes: using a two-stage process, with the first stage heating temperature at 100℃ and holding at that temperature for 10~15h, and the second stage heating temperature at 200℃ and holding at that temperature for 24~48h, to obtain the synthesized product.

5. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 1, characterized in that, The doping ions mentioned in step 1 include rare earth elements Eu and Dy, as well as co-doping elements; The co-doping element includes one or more of Na, Mg, Bi, Nb, Co, and La; The total amount of the two rare earth elements Eu and Dy accounts for 0.1% to 1% of the molar percentage of the barium titanate powder; the total amount of the co-doping elements accounts for 0.5% to 3% of the molar percentage of the barium titanate powder.

6. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 1, characterized in that, In step 2, the barium titanate powder and the oxide powder doped with ions are mixed and refined using a high-energy ball milling method. The ball milling time is 1-2 hours, the rotation speed is 2500-3000 rpm, and the ball milling medium is anhydrous ethanol.

7. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 1, characterized in that, The adhesive mentioned in step 3 is one of gum arabic, polyvinyl alcohol, polyvinyl butyral, polyacrylic acid, and hydroxymethyl cellulose; The solvent is one of deionized water and anhydrous ethanol.

8. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 1, characterized in that, The tableting process in step 4 includes: using a powder tableting machine to compress the powder into tablets at 15-30 MPa to obtain green tablets; and then using a cold isostatic press to densify the green tablets at 100-200 MPa for a holding time of 5-20 minutes.

9. The preparation method of barium titanate-based ceramic material based on rare earth ion doping according to claim 1, characterized in that, The sintering process described in step 5 is as follows: the temperature is increased from room temperature to 600℃ at a rate of 1~2℃ / min and held for 1~3 hours; then the temperature is increased to 1050~1250℃ at a rate of 3~5℃ / min and held for 1~3 hours.

10. The rare earth ion-doped barium titanate-based ceramic material prepared by any one of the preparation methods according to claims 1-9.

Images