A kind of antiferroelectric-like relaxation ceramic material and its preparation method and application

Abstract

The application belongs to the technical field of inorganic nonmetallic functional ceramic materials, and discloses a kind of antiferroelectric-like relaxor ceramic material and its preparation method and application, the chemical formula of the material is (1- x )(0.9Bi 0.5 Na 0.5 TiO3‑0.1BiMg 2 / 3 Nb 1 / 3 O3)‑ x CaTiO3, wherein 0.05≤ x ≤0.4, and the eigenvalue is x =0.3. By adopting stepwise solid-phase reaction method, 0.9Bi 0.5 Na 0.5 TiO3‑0.1BiMg 2 / 3 Nb 1 / 3 O3, CaTiO3 ceramic powder is synthesized in advance, then mixed by ball milling according to stoichiometric ratio, and sintered into ceramic. The prepared ceramic material has two-phase coexistence, flaky / honeycomb-shaped hetero-domain structure, polarization texture and vortex characteristics, and shows high reversible polarization strength, large breakdown field strength and excellent service stability, and has potential application in high-power pulse devices.

Description

Technical Field

[0001] This invention belongs to the field of inorganic non-metallic functional ceramic materials technology, specifically relating to an antiferroelectric relaxor ceramic material, its preparation method, and its application in high-power pulse devices. Background Technology

[0002] Dielectric capacitors remain unparalleled in applications requiring high power density, nanosecond response, and extreme temperature tolerance simultaneously. However, the rapid integration of renewable energy and the emergence of next-generation pulsed power systems have set unprecedented performance targets for these devices, which are still constrained by the modest releasable energy storage density of existing dielectric materials. W rec The limitations of traditional ferroelectric materials include high saturation polarization intensity, but also undesirable hysteresis losses and low breakdown electric fields. E b Linear media have high...; while linear media have high... E b and energy storage efficiency ( η The reversible polarization intensity is approximately 100%, but its saturation polarization intensity is low. Relaxors possess high reversible polarization intensity due to the presence of polar nanoregions or even polar clusters in the paraelectric matrix. E b This has become a promising compromise, but achieving high reversible polarization intensity and high... E b The ideal combination remains a huge challenge.

[0003] To address these challenges, researchers have begun to tailor the size and configuration of polar nanodomains to modulate energy storage properties. Among these, polarization texturing—the directional manipulation of nanodipoles—can effectively enhance reversible polarization intensity, thereby improving energy storage performance. W rec ,but η Further optimization is still needed. Furthermore, polarized vortices, with their continuously rotating polarization characteristics, offer a new path for ultra-low-loss capacitor energy storage. While this strategy can maintain high... η ,but W rec Further improvements are needed. These research results provide a breakthrough for integrating polarization texture and polarization vortex into the same bulk ceramic to further optimize the energy storage properties of the material. Summary of the Invention

[0004] Therefore, the present invention is aimed at large reversible polarization intensity and high E b The contradictory relationship, utilizing the coexistence of heterovalent ions at A and B sites to generate a local field, Mg 2+ With Nb 5+A scheme to optimize the energy storage properties of relaxor by synergistically constructing polarization texture and polarization vortexes based on the large difference in ionic radius and the twinning characteristics of CaTiO3 is proposed. This paper proposes a quasi-antiferroelectric relaxor ceramic material, its preparation method and application.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The first technical objective of this invention is to provide a type of antiferroelectric relaxor ceramic material, the chemical formula of which is (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x CaTiO3, where 0.05 ≤ x ≤ 0.4.

[0007] Furthermore, the characteristic values ​​of the chemical formula of the material are: x = 0.3.

[0008] The second technical objective of this invention is to provide a method for preparing an antiferroelectric relaxor ceramic material, which uses a solid-state reaction method to synthesize 0.9Bi 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 The antiferroelectric relaxor ceramic material described above is prepared by ball milling and mixing O3 and CaTiO3 ceramic powders according to stoichiometric ratio and sintering them into ceramic.

[0009] Furthermore, the 0.9Bi 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 The pre-synthesis temperature of O3 ceramic powder is 800~950 ℃, the time is 2~5 h, and the heating rate is 1-10 ℃ / min.

[0010] Furthermore, the pre-synthesis temperature of the CaTiO3 ceramic powder is 1000~1200 ℃, the time is 2~5 h, and the heating rate is 1-10 ℃ / min.

[0011] It should be noted that, using 0.9Bi 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 The phase formation temperature difference and ion lattice mismatch between the two material systems, O3 ceramic powder and CaTiO3 ceramic powder, induce polarization texture and vortex generation.

[0012] Furthermore, the (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x The sintering heating rate of CaTiO3 ceramic materials is 1~10 ℃ / min, the sintering temperature is 1200~1300 ℃, and the time is 2~5 h.

[0013] The third technical objective of this invention is to provide an application of the antiferroelectric relaxor ceramic material described above in high-power pulse devices.

[0014] As can be seen from the above technical solution, compared with the prior art, the beneficial effects of the present invention are as follows:

[0015] 1. This invention defines the material having Pbnm and P 4 / mbm The coexistence of two phases, the sheet-like / honeycomb heterodomain structure, and the polarization texture and vortex features exhibit high reversible polarization intensity, large breakdown field strength, and excellent service stability, making it a potential candidate for high-power pulse devices.

[0016] 2. The materials of this invention are environmentally friendly and the process is simple, which is expected to provide a new technical path for the design and preparation of high-performance, high-stability nonlinear dielectric energy storage materials. Attached Figure Description

[0017] 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, the drawings in the following description are only embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the provided drawings without creative effort.

[0018] Figure 1 For (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x Refined X-ray diffraction pattern of CaTiO3 ceramic material: (a) x = 0.05、(b) x = 0.3 and (c) x = 0.4.

[0019] Figure 2 For (1- x (0.9Bi) 0.5 Na0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x Scanning electron microscope image of CaTiO3 ceramic material: (a) x = 0.05、(b) x = 0.3 and (c) x = 0.4.

[0020] Figure 3 For (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x CaTiO3 ceramic material (a) E b The relationship between lower polarization intensity and electric field intensity ( P - E (a) Relationship curve, (b) W rec and η Follow E The relationship of change and (c) E b The following components W rec and η .

[0021] Figure 4 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 (a) Scanning electron microscope image of O3-0.3CaTiO3 ceramic material and (b) elemental surface scan image.

[0022] Figure 5 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 Three-dimensional image of time-of-flight secondary ion mass spectrometry of O3-0.3CaTiO3 ceramic material.

[0023] Figure 6 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 (a) Transmission electron microscope image of O3-0.3CaTiO3 ceramic material and (b) Selected area electron diffraction pattern of regions 1-3.

[0024] Figure 7 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 High-angle annular dark-field-scanning transmission electron microscope images of (a) region 1 and (b) region 2 of O3-0.3CaTiO3 ceramic material and their polarization vector distribution diagrams.

[0025] Figure 8 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)-0.3CaTiO3 ceramic materials under different (a) temperatures, (b) frequencies, and (c) cycles P - E Curve and (df) corresponding W rec and η . Detailed Implementation

[0026] The technical solutions in the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0027] Raw material sources: Bi2O3 (99.9%, Sinopharm Shanghai Chemical Reagent Co., Ltd.), Na2CO3 (98.0%, Sinopharm Shanghai Chemical Reagent Co., Ltd.), TiO2 (99.0%, Sinopharm Shanghai Chemical Reagent Co., Ltd.), MgO (99%, Sinopharm Shanghai Chemical Reagent Co., Ltd.), Nb2O5 (99.9%, Sinopharm Shanghai Chemical Reagent Co., Ltd.) and CaCO3 (99.0%, Sinopharm Shanghai Chemical Reagent Co., Ltd.).

[0028] The present invention relates to (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x The preparation process of CaTiO3 ceramic materials is as follows:

[0029] (1) Weigh the required oxide or carbonate according to the stoichiometric ratio, then place the weighed raw material in a tetrafluoroethylene ball mill jar and wet-mill for 20 h, then discharge, dry, and pre-calcine at 800~950 ℃ and 1000~1200 ℃ for 2~5 h to obtain 0.9Bi. 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3, CaTiO3 ceramic powder;

[0030] (2) Weigh the above ceramic powder according to the stoichiometric ratio, ball mill, discharge and dry, then use 8~10% polyvinyl alcohol as a binder to granulate the mixed powder, and press it into ceramic green sheets through a molding die under a pressure of 10~100 MPa.

[0031] (3) The ceramic green sheets are arranged and bonded at 550~600℃, and then heated to 1200~1300℃ at a heating rate of 1~10℃ / min, and sintered for 2~5 h to obtain (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3) - x CaTiO3 ceramic materials.

[0032] Examples 1-5

[0033] 0.9Bi 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3 ceramic powder: Weigh the required Bi2O3, Na2CO3, TiO2, MgO and Nb2O5 according to the stoichiometric ratio, place the weighed raw materials in an agate ball mill jar and wet grind for 20 h, then discharge, dry, press into blocks, and pre-fire at 850 ℃ for 4 h at a heating rate of 3 ℃ / min.

[0034] CaTiO3 ceramic powder: Weigh the required CaCO3 and TiO2 according to the stoichiometric ratio, place the weighed raw materials in an agate ball mill jar and wet grind for 20 h, then discharge, dry, press into blocks, and pre-fire at 1100℃ for 3 h at a heating rate of 3 ℃ / min.

[0035] (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- xCaTiO3 ceramic material: The obtained 0.9Bi 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3 and CaTiO3 ceramic powders were weighed according to stoichiometric ratio and wet-milled in an agate ball mill jar for 20 h. After discharge and drying, the mixed powder was granulated using 8-10% polyvinyl alcohol as a binder. The granules were then pressed into ceramic green sheets using a molding die at 20 MPa. After debinding at 550 ℃, the green sheets were sintered at 1210-1215 ℃ for 2 h at a heating rate of 3 ℃ / min to obtain (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x CaTiO3 ceramic materials, among which x = 0.05, 0.1, 0.2, 0.3, 0.4.

[0036] Figure 1 For (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x The refined X-ray diffraction pattern of CaTiO3 ceramic materials shows that the addition of a small amount of CaTiO3 promotes partial ferroelectric trigonal... R 3 c Transformed into four sides P 4 bm Phase, while the addition of high concentrations of CaTiO3 induces orthogonalization. Pbnm Xianghe Shundian Sifang P 4 / mbm Phase formation.

[0037] Figure 2 For (1- x (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x Scanning electron microscope images of CaTiO3 ceramic materials show that all ceramic samples exhibit a dense microstructure with interspersed black and white grains, and the number of black grains increases with the increase of CaTiO3 addition.

[0038] Figure 3 For (1- x (0.9Bi) 0.5Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)- x CaTiO3 ceramic materials P - E Curves and corresponding W rec and η The results showed that as the amount of CaTiO3 added increased, the ceramic material... PE The curve gradually evolved from a waist-cinching shape to a linear curve, especially... x = 0.3% of the composition exhibits an antiferroelectric-like structure. PE Curves; Although the addition of CaTiO3 reduced the maximum polarization and remanent polarization, it simultaneously enhanced their... E b ; x =0.3 component in E b = 640 kV cm -1 At that time, obtain W rec = 11.17 J cm -3 , η = 94.5%.

[0039] Experimental Example

[0040] Selecting eigenvalues x =0.3, that is, 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 The microstructure and service stability of the O3-0.3CaTiO3 ceramic material were analyzed.

[0041] Figure 4 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 Scanning electron microscope images and elemental surface scans of O3-0.3CaTiO3 ceramic materials show that the black grains in the ceramic materials are Bi-deficient and Mg-rich phases.

[0042] Figure 5 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 Three-dimensional time-of-flight secondary ion mass spectrometry images of O3-0.3CaTiO3 ceramic materials, showing that Bi 3+ Mg2+ There is a clear bias in the analysis.

[0043] Figure 6 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 Transmission electron microscopy (TEM) images and corresponding selected area electron diffraction (SED) patterns of O3-0.3CaTiO3 ceramic materials show that the ceramic material exhibits a lamellar / honeycomb heterodomain structure, with the lamellar domain structure possessing strong... Pbnm Diffraction lattice, while honeycomb domain structure has relatively weak diffraction. Pbnm Diffraction lattice.

[0044] Figure 7 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 High-angle annular dark-field-scanning transmission electron microscope images and polarization vector distribution maps of O3-0.3CaTiO3 ceramic materials. The results show that region 1 has a polar texture with a small number of polar vortex features between the polar textures, while region 2 has a large number of polar vortex features.

[0045] Figure 8 It is 0.7 (0.9Bi) 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)-0.3CaTiO3 ceramic material at 480 kVcm -1 Temperature, frequency, and cyclic stability under an electric field were measured, with results showing performance within the temperature range of 20–200 °C. W rec and η The values ​​were 5.63 ± 0.14 J / cm. -3 With 98.3±5.5%, in the frequency range of 10~200 Hz W rec and η The values ​​were 5.92 ± 0.04 J / cm. -3 With 97.4±3.1%, in 1~10 5 Within the loop count range W rec and η The values ​​were 6.04 ± 0.05 J / cm. -3 With a stability of 98.8±1.6%, it demonstrates excellent service stability.

[0046] The above description of the disclosed embodiments enables those skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the invention is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A type of antiferroelectric relaxor ceramic material, characterized in that, The chemical formula of the material is (1-x)(0.9Bi). 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)-xCaTiO3, where 0.05 ≤ x ≤ 0.4; The preparation method of the antiferroelectric relaxor ceramic material is as follows: 0.9Bi is pre-synthesized using a stepwise solid-state reaction method. 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 The antiferroelectric relaxor ceramic material described above is prepared by ball milling and mixing O3 and CaTiO3 ceramic powders according to stoichiometric ratio and sintering them into ceramic.

2. The antiferroelectric relaxor-like ceramic material according to claim 1, characterized in that, The chemical formula of the antiferroelectric relaxor ceramic material is 0.7(0.9Bi). 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 O3)-0.3CaTiO3.

3. The antiferroelectric relaxor-like ceramic material according to claim 1, characterized in that, The 0.9Bi 0.5 Na 0.5 TiO3-0.1BiMg 2 / 3 Nb 1 / 3 The pre-synthesis temperature of O3 ceramic powder is 800~950 ℃, the time is 2~5 h, and the heating rate is 1-10℃ / min.

4. The antiferroelectric relaxor-like ceramic material according to claim 1, characterized in that, The pre-synthesis temperature of the CaTiO3 ceramic powder is 1000~1200 ℃, the time is 2~5 h, and the heating rate is 1-10 ℃ / min.

5. The antiferroelectric relaxor-like ceramic material according to claim 1, characterized in that, In the sintering process, the heating rate is 1~10 ℃ / min, the sintering temperature is 1200~1300 ℃, and the time is 2~5 h.

6. The application of the antiferroelectric relaxor ceramic material as described in claim 1 in high-power pulse devices.

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