CN-121517209-B - Anti-reduction two-phase-opposite ferroelectric energy storage ceramic and preparation method and application thereof

Abstract

The invention relates to the technical field of ceramics, in particular to anti-reduction two-phase-opposite ferroelectric energy storage ceramic and a preparation method and application thereof. The structural general formula of the ceramic is Pb a La b Zr c Ti d O e +xwt%Y 2 O 3 , wherein a=0.5-1.5, b=0.01-0.1, c=0.5-1.5, d=0.005-0.05, e=1.6-4.7, and 0< x <8. By adding the Y 2 O 3 with specific content, the stability of the ceramic antiferroelectric phase is improved, the dispersion relaxation of ceramic materials is promoted, the breakdown electric field of the antiferroelectric ceramic is improved, the reduction resistance of the ceramic is also improved, the prepared ceramic has the energy storage density of 10-12J/cm 3 and the energy storage efficiency of more than 80% by matching with a specific casting process, and can be used for an energy storage capacitor and has good application prospect in a pulse power system.

Inventors

• ZHAO YE
• CAO LEI
• HAN PEI
• LU CHUNXIAO
• ZHANG LIWEN
• LI YONG

Assignees

• 内蒙古科技大学

Dates

Publication Date

20260508

Application Date

20260114

Claims (8)

1. 1. The anti-reduction two-phase anti-ferroelectric energy storage ceramic is characterized by having a structural general formula of Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 O 3 +xwt%Y 2 O 3 , wherein x is more than or equal to 3 and less than or equal to 5, and Y 2 O 3 and Pb 0.94 La 0.04 Zr 0.99 Ti 0.01 O 3 can generate a second phase yttrium zirconate of the ceramic.
2. 2. The ceramic of claim 1, wherein the ceramic is prepared from Pb 3 O 4 、La 2 O 3 、ZrO 2 、TiO 2 and Y 2 O 3 .
3. 3. The ceramic of claim 2, wherein the raw materials for preparing the ceramic further comprise a solvent and an auxiliary agent, and the auxiliary agent comprises at least one of a dispersing agent, a binder, a plasticizer and a homogenizing agent.
4. 4. A method for preparing the ceramic according to claim 3, which is characterized by comprising the following steps of preparing Pb 3 O 4 、La 2 O 3 、ZrO 2 、TiO 2 and Y 2 O 3 according to the stoichiometric ratio of the general formula of the ceramic structure, ball-milling and mixing Pb 3 O 4 、La 2 O 3 、ZrO 2 、TiO 2 and Y 2 O 3 uniformly, drying, presintering, ball-milling again to obtain powder, ball-milling and mixing the powder with a solvent and an auxiliary agent to form casting slurry, preparing a casting film through a casting process, laminating and pressing to obtain a ceramic green body, discharging glue of the ceramic green body, and then carrying out piling sintering in a reducing atmosphere to obtain the ceramic.
5. 5. The method for preparing ceramic according to claim 4, wherein the pre-sintering treatment is performed by adopting a secondary pre-sintering process, the temperature of the secondary pre-sintering process is 700-900 ℃, the heating rate is 1-8 ℃ per minute, the cooling rate is 3-15 ℃ per minute, and the heat preservation time is 2-5 hours.
6. 6. The method for preparing ceramic according to claim 4, wherein the temperature of the adhesive discharge is 450-700 ℃, the temperature rising rate is 0.5-3 ℃ per minute, the temperature lowering rate is 3-5 ℃ per minute, and the heat preservation time is 3-5 hours.
7. 7. The method for preparing ceramic according to claim 4, wherein the reducing atmosphere comprises nitrogen and hydrogen, the volume ratio of the nitrogen to the hydrogen is 200 (0.5-3), the temperature of the pile-up sintering is 1000-1200 ℃, the heating rate is 3-8 ℃ per minute, the cooling rate is 3-10 ℃ per minute, and the heat preservation time is 3-5 h.
8. 8. Use of a ceramic according to any one of claims 1-3 for the manufacture of a dielectric storage capacitor.

Description

Anti-reduction two-phase-opposite ferroelectric energy storage ceramic and preparation method and application thereof Technical Field The invention relates to the technical field of ceramics, in particular to anti-reduction two-phase-opposite ferroelectric energy storage ceramic and a preparation method and application thereof. Background With the rapid development of new energy automobiles, 5G communication and high-power pulse technology, the application requirements of high-voltage high-power multilayer ceramic capacitors (MLCC) are increasingly vigorous, and energy storage ceramic materials are used as core media of the MLCC, so that the MLCC becomes a key direction of technology research and development. The antiferroelectric ceramic has remarkable advantages in high-voltage and high-power scenes due to high current throughput capability when the electric field induces phase transition, wherein lead-based ceramics such as PLZT (lead lanthanum zirconium titanium) base, PLZST (lead lanthanum zirconium strontium titanium) base and the like become main flow research objects by virtue of excellent dielectric and ferroelectric properties. However, the existing energy storage ceramics still have a plurality of technical bottlenecks. On the one hand, the reduction resistance is insufficient, the problems of oxygen vacancy, metal lead precipitation and the like are easy to occur, the lattice structure is destroyed, the electrical property is reduced, and the co-firing requirement of the low-cost base metal (Ni and Cu) inner electrode is difficult to adapt. On the other hand, the high-temperature stability is limited, and most ceramics cannot meet the use requirement of extreme working conditions because of the phenomena of dielectric constant fluctuation, breakdown strength reduction and dielectric loss increase caused by domain wall motion enhancement and defect migration aggravation in the environment with the temperature of more than 150 ℃. In addition, the conventional solid-phase method has the problem of high sintering temperature (usually more than 1300 ℃), abnormal growth of grains and increase of pores are easy to cause, and the energy storage efficiency and reliability of the material are further affected. The Chinese patent application CN115947598A discloses an antiferroelectric material which can be co-fired with an internal electrode of base metal and a preparation method thereof, wherein the sintering temperature of PLZST-base ceramic is reduced to 960 ℃ by adding glass auxiliary agent, and the energy storage density of 2.52J/cm 3 and the energy storage efficiency of 80% are still maintained under the low-oxygen atmosphere, so that preliminary base metal co-firing adaptation is realized. However, the patent adopts a single tetragonal phase structure design, the energy storage density is only 3.72J/cm 3 at most, the anti-reduction performance depends on the physical barrier of a glass phase, the deep synergy of anti-reduction and high energy storage is not realized from the intrinsic structure of the material, and the stability of a wide temperature area is not effectively optimized. Disclosure of Invention The invention provides an anti-reduction two-phase anti-ferroelectric energy storage ceramic which has a structural general formula of Pb aLabZrcTidOe+xwt%Y2O3, wherein a=0.5-1.5, b=0.01-0.1, c=0.5-1.5, d=0.005-0.05, e=1.6-4.7, and 0< x <8. Optionally, the value range of x is 2-6. Optionally, the value range of x is 3-5. The structural general formula of the limited ceramic is Pb aLabZrcTidOe+xwt%Y2O3, wherein a=0.5-1.5, b=0.01-0.1, c=0.5-1.5, d=0.005-0.05, e=1.6-4.7, and 0< x <8. By adding the Y 2O3 with specific content, the stability of the ceramic antiferroelectric phase is improved, the dispersion relaxation of the ceramic material is promoted, the breakdown electric field of the antiferroelectric ceramic is improved, and the reduction resistance of the ceramic is also improved. It is possible that Y 2O3 and the main phase perovskite structure produce synergistic effect, Y 2O3 reacts with Zr element in the main phase to form high-unordered defective fluorite structure second phase yttrium zirconate after being added in the primary mixing stage of ingredients and through the secondary presintering and reducing atmosphere sintering process, and the second phase and the main phase perovskite structure form a stable two-phase coexistence system. On one hand, vacancies with high disordered arrangement in fluorite structure can induce main opposite ferroelectric to generate diffusion relaxation transformation, inhibit violent movement of domain wall, make antiferroelectric-ferroelectric phase shift to high electric field direction, obviously raise thermodynamic stability of antiferroelectric phase, reduce energy loss in phase change process, on the other hand, second phase particles are uniformly dispersed in main phase matrix, can effectively prevent abnormal growth of crystal grains, implement