80 results about "Ferroelectric ceramics" patented technology

The invention discloses a preparation method and application of a vertically-oriented ferroelectric ceramic-polymer composite solid electrolyte, and belongs to the field of application of solid-state lithium metal batteries. The electrolyte membrane is composed of polyvinylidene fluoride, ferroelectric ceramic powder, lithium salt and the like. The ferroelectric ceramic can form dipoles under the action of an electric field, polyvinylidene fluoride conformation is induced to be converted from an alpha phase to a beta phase, the beta conformation has large dipole moment, dissociation of lithium salt can be promoted, and more free lithium ions are generated. Through multi-solvent blending, the freezing orientation technology can be adjusted, the ferroelectric ceramic-polymer composite solid electrolyte membrane of a vertical ordered structure is prepared, and the shortest path of transmission of lithium ions between a positive electrode and a negative electrode is achieved. The vertically oriented ferroelectric ceramic-polymer composite solid electrolyte can promote lithium salt dissociation, reduce the transportation tortuosity of lithium ions and increase the ionic conductivity. The battery assembled by the material can effectively inhibit the growth of lithium dendrites, and has excellent rate capability and cycling stability.

The invention discloses PZT-based ferroelectric ceramic with high radial resonant frequency and temperature stability as well as a preparation method and application of the PZT-based ferroelectric ceramic. The composition of the PZT-based ferroelectric ceramic is 0.1 Pb (Yb1 / 2Nb1 / 2) O3-0.9 Pb (Zr1-xTix) O3 (0.1 PYN-0. 9PZT). According to the invention, a large signal test system is adopted to obtain data similar to actual working conditions, and data fitting and differential processing are combined to more reliably evaluate the radial resonant frequency temperature stability. It is found that components with x equal to 0.56 are excellent in performance, and the radial resonant frequency temperature coefficient TCfr (25 DEG C) is 64 * 10 <-6 > / DEG C under small signal excitation; under large signal excitation, when Eac is increased from 5V / mm to 20V / mm, TCfr (25 DEG C) is changed from 0 * 10 <-6 > / DEG C to-68.3 * 10 <-6 > / DEG C. In addition, the component is simple in preparation method, low in raw material cost and wide in application prospect.

The invention discloses pure-phase bismuth ferrite-strontium titanate ceramic as well as a preparation method and application thereof, and belongs to the field of lead-free ferroelectric ceramic. Comprising the following steps: filling pure-phase BFO-STO precursor powder prepared by a hydrothermal method into a graphite mold, controlling the heating rate to a sintering temperature, and sintering under the conditions of external pressure and heat preservation, so as to finally prepare the BFO-STO ceramic. The BFO-STO ceramic is prepared through SPS sintering, volatilization of Bi < 3 + > and generation of impure phases are effectively inhibited, ferroelectric, dielectric and magnetic properties of the BFO ceramic are effectively improved, and possibility is provided for practical application of the BFO-STO ceramic in the fields of functional sensors, magnetic memories, piezoelectric generators, high-temperature inductors and the like.

The invention discloses a ferroelectric energy storage ceramic capacitor capable of being charged / discharged quickly and a preparation method, and relates to the field of functional ceramics and electronic devices, the ceramic component is (0.7-x) BiFeO3-0. 3BaTiO3-xBaZn1 / 3Nb2 / 3O3 + 0.1 wt% MnO2, the adopted preparation method is a high-temperature solid-phase reaction method, an upper top electrode and a bottom electrode are evaporated on the upper surface and the lower surface of a ceramic sample respectively, and the upper surface and the lower surface of the ceramic sample are subjected to high-temperature solid-phase reaction to obtain the ferroelectric energy storage ceramic capacitor capable of being charged / discharged quickly. A test result shows that the lead-free ferroelectric ceramic has relatively high energy storage density and charge-discharge rate; the preparation method has the outstanding advantages of simple preparation conditions, simple preparation process, stable energy storage characteristic, high charging and discharging speed and suitability for batch production.

The application relates to a high-entropy antiferroelectric ceramic with high polarization intensity and high energy storage performance as well as a preparation method and application thereof, wherein the chemical composition of the high-entropy antiferroelectric ceramic is (Pb 0.87 Ba 0.05 Sr 0.05 La 0.02 )(Zr 0.42 Hf 0.18 Sn 0.39 Ti 0.01 )O3. The application realizes a maximum polarization intensity of 69 muC / cm 2 under a 71kV / mm electric field through high-entropy design, and finally obtains a novel antiferroelectric dielectric ceramic with a storage density of 14.2 J / cm 3 , which can be used for multilayer ceramic capacitor preparation and has a wide application prospect in high-power pulse systems.

The application discloses a preparation method for regulating and controlling ferroelectric texture ceramic grain size by using a phase field method simulation technology, and comprises the following steps: preparing a series of microcrystalline powders with different size distributions; setting an initial phase field structure meeting the particle size distribution; establishing a phase field model for grain orientation growth; simulating and analoging the grain orientation growth process; preparing a film; preparing a green body with microcrystalline parallel distribution; and preparing ferroelectric texture ceramics with target grain size distribution. The application fully utilizes the computer simulation intelligent prediction guidance technology, does not need repeated trial and error experiments, saves time and effort, has good product reproducibility and stability, easily realizes accurate control of the ferroelectric texture ceramic grain size distribution, and is easy to be industrialized; the application effectively controls the occurrence of grain abnormal growth, maintains high grain orientation, and promotes the densification of the ceramic; and the application can not only prepare high-texture-density ferroelectric ceramics, but also regulate and control the grain size.

The invention discloses a heat treatment method of high-polarization-intensity bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic, which comprises the following steps: arranging an electrode on the surface of a bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic sintered body, and then putting the sintered body into a rapid annealing furnace; the preparation method comprises the following steps: heating to 550-650 DEG C from room temperature at a heating rate of 5-80 DEG C / s, carrying out heat preservation for 45-75 seconds, carrying out first rapid annealing, and cooling to room temperature at a cooling rate of 250-350 DEG C / s, thereby obtaining the bismuth ferrite-lead titanate-barium zirconate titanate based ferroelectric ceramic. The heat treatment method provided by the invention can rearrange defects in the ceramic, increase domain conversion switches, improve the performance of the ceramic, and improve the performance of the ceramic. Furthermore, the ferroelectric piezoelectric property of the polarized BF-PT-BZT ceramic is greatly improved, and meanwhile, the polarized BF-PT-BZT ceramic has high Curie temperature.

The application discloses a battery based on beta radiation volt effect of 147Pm doped ferroelectric ceramic and a preparation method thereof, and the battery comprises an upper electrode layer, 147 a Pm doped ferroelectric ceramic layer and a lower electrode layer; the upper electrode layer, the ferroelectric ceramic layer and the lower electrode layer are sequentially connected. 147 By doping Pm into the ferroelectric ceramic, the effective combination of the energy conversion device and the radioactive source is realized, the energy loss caused by the self-absorption of the radioactive source and the energy deposition on the surface of the energy conversion material is eliminated, and the energy utilization rate of the battery is greatly improved. 147 By doping Pm in the ferroelectric ceramic, the conductivity of the ferroelectric ceramic is effectively improved. 147 Pm is a radioactive element, and beta rays are radiated in the decay process; by doping Pm into the ferroelectric ceramic, the integration of the radioactive source and the energy conversion device is realized, the conductivity of the ferroelectric ceramic is greatly improved, and higher conversion efficiency is obtained.

The invention relates to a BNT-based lead-free relaxor antiferroelectric ceramic material as well as a preparation method and application of the BNT-based lead-free relaxor antiferroelectric ceramic material. The chemical composition of the BNT-based lead-free relaxation antiferroelectric ceramic material is (Bi < 0.5-x > Pr < x > Na < 0.5 >) TiO < 3 >-0.1 wt% MnCO3, wherein x is mole percent, and x is more than 0.10 and less than or equal to 0.20.

The invention relates to the technical field of functional ceramic preparation, and particularly discloses a preparation method of an A-site doped PLZST-based anti-ferroelectric ceramic material, the chemical general formula of the anti-ferroelectric ceramic material is (Pb0.99-xLax) (Zr0. 6Sn0. 4) 0.9 Ta0. 02O3, the doping amount of A-site La is accurately limited in a range of 0.01 < = x < = 0.04, and multiple effects caused by La doping are effectively balanced. In the preferable range, the A-site vacancy generated by Laintroduction can be fully utilized to refine crystal grains and inhibit oxygen vacancy, so that the breakdown electric field intensity and insulativity of the material are remarkably improved, and the adverse effect of excessive doping on the saturation polarization intensity of the material is avoided. The coordination of high breakdown field strength, low hysteresis loss and high saturation polarization is realized, so that the obtained ceramic material has high energy storage density and high energy storage efficiency.

The application relates to the technical field of inorganic nonmetal functional ceramic materials, and discloses a polar vortex structure relaxor ferroelectric ceramic material and a preparation method and application thereof, the material is of a chemical formula (1-x)(0.7NaNbO3-0.3Sr 0.7 Bi 0.2 TiO3)-xCaSnO3, wherein 0<=x<=0.2, and a characteristic value is x=0.1. By adopting a step-by-step solid-phase reaction method, NaNbO3, Sr 0.7 Bi 0.2 TiO3 and CaSnO3 ceramic powders are pre-synthesized, then are ball-milled according to a stoichiometric ratio and are sintered into ceramics. The prepared ceramic material has a multi-phase coexistence, core-shell and polar vortex structure, and exhibits high saturation polarization intensity, low hysteresis, large breakdown field strength and excellent service stability, and has potential application in high-power pulse devices. The material is environment-friendly and simple in process, and is expected to provide a new technical path for design and preparation of high-performance and high-stability nonlinear dielectric energy storage materials.

The application relates to a structural health monitoring system and application thereof. A preparation method of a carbon fiber reinforced thermoplastic composite material involved in the system comprises the following steps: providing a plurality of carbon fiber reinforced thermoplastic resin layers; prepositioning a multifunctional sensor unit array between adjacent thermoplastic resin layers, the multifunctional sensor unit array comprising a functional film containing ferroelectric ceramic, an electrode layer, and an insulating protective layer between the functional film and the carbon fiber layer; wherein the functional film comprises ferroelectric ceramic material with dielectric and piezoelectric response characteristics; and performing selective laser solidification on the layer area prepositioned with the multifunctional sensor unit array, so that the layer interface locally melts under the action of laser heating and embeds the multifunctional sensor unit array between adjacent layers; wherein the peak temperature of the laser heating area in the selective laser solidification process is not higher than 200 DEG C.

The invention belongs to the field of functional ceramics, and particularly relates to a BNT-based pyroelectric ceramic material as well as a preparation method and application thereof. In order to obtain a lead-free pyroelectric material with excellent pyroelectric performance and good temperature stability, the invention provides a BNT-based lead-free pyroelectric ceramic material, the chemical composition of the BNT-based lead-free pyroelectric material is (Bi < 0.5-x > Pr < x > Na < 0.5 >) TiO < 3-y > wt% MnO2, x is more than or equal to 0.01 and less than or equal to 0.04, and y is more than 0 and less than or equal to 0.1. BNT is selected as a base material, the Pr element is doped, the pyroelectric coefficient can be improved, and the lead-free pyroelectric infrared detector is expected to be applied to the field of lead-free pyroelectric infrared detection.

The invention relates to the technical field of solid refrigeration materials, in particular to a barium titanate-based ferroelectric ceramic electrocaloric material and a preparation method thereof. The electrocaloric material is of a three-layer structure and sequentially comprises a first outer layer, a middle layer and a second outer layer, the first outer layer and the second outer layer are made of BZT-BST doped B2O3 ceramic materials, and the middle layer is made of BZT-BST doped MgO ceramic materials; through the sandwich structure design, the middle layer bears most voltage, and the overall breakdown field strength is remarkably improved. Due to the introduction of B2O3, the sintering temperature is reduced, and firm co-firing with a metal electrode is realized; by doping MgO, the insulating property of the middle layer is improved, and meanwhile, the ferroelectric property of the system is kept. The material can realize the electrocaloric temperature change of 2.05 K and the heat absorption capacity of 4.6 * 10 <-3 > J under the conditions of a 90kV / cm electric field and room temperature, has high pressure resistance, large refrigerating capacity and good reliability, and is suitable for the solid-state refrigeration field such as heat management of electronic devices.

The invention discloses a PZT-54 / 46 ferroelectric ceramic for improving direct current pulse voltage resistance through acid leaching pretreatment and a preparation method thereof, namely, Pb3O4 with the purity of 99.75%, ZrO2 with the purity of 99.6% and TiO2 with the purity of 99.72% are taken as original raw materials and are proportioned according to a stoichiometric ratio, 1mol% of Pb3O4 is additionally added to compensate lead volatilization, an analytically pure nitric acid solution is added into the mixture for pretreatment, and the PZT-54 / 46 ferroelectric ceramic is prepared through acid leaching pretreatment. And drying by distillation, drying and grinding, sintering in a muffle furnace to obtain compact ceramic, and finally coating a silver electrode and polarizing. Compared with a traditional solid phase method without acid leaching pretreatment, the leakage current density of the PZT ceramic prepared by the method is reduced, and the direct current pulse compression strength of the ceramic is improved. And the high-reliability PZT-54 / 46 ferroelectric ceramic with excellent voltage resistance and stable ferroelectric performance is obtained.

The invention relates to the technical field of temperature detection and strain testing, and discloses a wireless passive / temperature strain two-parameter sensing element based on a precursor polymer ferroelectric composite ceramic film and a preparation method of the wireless passive / temperature strain two-parameter sensing element. The composite dielectric coating comprises a substrate, an insulating layer and a composite dielectric layer from bottom to top, and the composite dielectric layer is prepared by mixing a precursor ceramic polymer with ferroelectric ceramic powder through high-temperature pyrolysis; the temperature sensitive structure and the strain sensitive structure are both comb tooth structures and are matched with the internal inductor and the external inductor to form an independent LC resonant circuit, the dielectric constant or the polar plate distance is changed through the environment temperature and deformation, the LC resonant frequency is changed, the temperature and the strain are effectively measured, and the working state of a measured structural part can be visually reflected.

The application discloses a water-based tape casting slurry of a magnetoelectric composite ceramic sheet and a method for preparing the magnetoelectric composite ceramic sheet by water-based tape casting. 0.5 Na 0.4 K 0.1 TiO3, magnetic powder hexaferrite BaFe 12 O 19 , polyacrylic acid, polyurethane emulsion and polyacrylic acid emulsion mixture, polyethylene glycol and deionized water. The water-based tape casting process for preparing the magnetoelectric composite ceramic sheet comprises slurry preparation, tape casting, drying and sintering into a film, wherein a magnetic field is applied during the drying process of the wet film, and a composite structure of the magnetic powder oriented in the ferroelectric matrix is constructed. The magnetoelectric composite ceramic sheet prepared by the application has ferroelectricity and ferromagnetism, has a high magnetoelectric voltage coefficient and a magnetic dielectric response, and can be used in the fields of functional devices such as magnetoelectric sensors and energy converters; meanwhile, the ceramic sheet preparation process is simple, the conditions are easy to control, is environment-friendly and is suitable for batch production.

The screening device for preparing the ferroelectric ceramics comprises a material barrel, a net barrel, a swinging mechanism and a driving mechanism are arranged in the material barrel, the swinging mechanism comprises a swinging rod and a springback assembly, the driving mechanism is used for driving the swinging rod and the net barrel to rotate, the net barrel screens materials through self rotation, and the springback assembly is used for driving the swinging rod to rotate reversely and reset. The swing rod knocks the net cylinder through forward and reverse rotation to trigger vibration, the swing rod comprises a rotating disc, a rocker arm and a pendulum bob, and the swing rod knocks the net cylinder through the pendulum bob. The motor is used for driving the mesh cylinder to rotate, meanwhile, the swing rod can be driven to rotate, materials can be screened through rotation of the mesh cylinder, the second cover shell can be hit through rotation of the swing rod to enable the mesh cylinder to vibrate, and therefore the materials can be prevented from blocking meshes in the mesh cylinder, and the material screening efficiency of the mesh cylinder is maintained.

The application relates to a high-entropy antiferroelectric ceramic material with high energy storage performance and a preparation method and application thereof. 0.2 Ca 0.2 Pb 0.2 Bi 0.2‑x La x Na 0.2 )TiO3, wherein 0 The application successfully designs and obtains a high-entropy antiferroelectric ceramic for the first time, has excellent high energy storage efficiency and high energy storage density, and is widely applied to multilayer ceramic capacitors.

The invention belongs to the field of ceramic materials, and particularly relates to a lead-free ferroelectric ceramic material and a preparation method thereof.The preparation method comprises the steps that aluminum nitrate nonahydrate and titanium isopropylate are dissolved in ethylene glycol and stirred, a citric acid solution is added, stirring continues, and a precursor solution A is prepared; dissolving bismuth nitrate pentahydrate in a citric acid solution, and stirring to prepare a precursor solution B; mixing the precursor solution A and the precursor solution B, stirring and drying to form gel; drying, grinding and crushing the gel, and calcining to obtain ceramic powder; the preparation method comprises the following steps: uniformly mixing ceramic powder and nano barium titanate powder by taking deionized water as a medium, and drying to obtain precursor powder; grinding and granulating the precursor powder and a 5wt% polyvinyl alcohol solution in an agate mortar, and then applying axial pressure to form a green body; and putting the green body into a corundum crucible with a cover, and sintering by using a two-step method to finally obtain the lead-free ferroelectric ceramic material. According to the invention, a universal combined optimization strategy is provided, and a strong relaxation ferroelectric system is developed.

The invention discloses a lead-free ferroelectric ceramic with a high electrostriction coefficient and a preparation method thereof, the chemical formula of the lead-free ferroelectric ceramic is Ba (Zr < 0.25 > Ti < 0.75 >) O < 3-x > (Ba < 0.7 > Ca < 0.3 >) TiO3, and x is more than 0.49 and less than 0.51; the preparation method comprises the following steps: 1, selecting raw materials; 2, respectively ball-milling the raw materials, mixing, drying and sieving; 3, pre-sintering treatment; 4, pelletizing after ball milling; 5, pressing a green body; and 6, sintering treatment. The tetragonal phase and orthogonal phase coexisting lead-free ferroelectric ceramic is obtained by doping different contents of tetragonal phase (Ba0. 7Ca0. 3) TiO3 into trilateral phase Ba (Zr0. 25Ti0. 75) O3, the crystal lattice stability is remarkably reduced by utilizing the symmetry of a multiphase coexisting crystal structure, the electrostriction coefficient of the lead-free ferroelectric ceramic is improved, and the lead-free ferroelectric ceramic is suitable for the fields of high-precision drivers, sensors and the like.

The invention relates to the technical field of dielectric refrigeration device materials, in particular to bismuth ferrite-based lead-free ferroelectric ceramic with a negative electrocaloric effect as well as a preparation method and application of the bismuth ferrite-based lead-free ferroelectric ceramic, the chemical composition of the bismuth ferrite-based lead-free ferroelectric ceramic is 0.7 BiFe < 0.999 > Mn < 0.001 > O < 3-0.3 > BaTi < 1-x > Sn < x > O < 3 >, and x is greater than or equal to 0 and less than or equal to 0.1. The bismuth-ferrite-based lead-free ferroelectric ceramic has a wide working temperature area, a working temperature range close to room temperature and a relatively large negative electrocaloric effect, does not cause harm to the ecological environment and human health in the preparation, use and waste processes, and is suitable for development of miniature refrigerators in the future.

The invention discloses a high-temperature-resistant dielectric energy storage ceramic material and a preparation method thereof.The high-temperature-resistant dielectric energy storage ceramic material is composed of BaCO3, CaCO3, SrCO3, Bi2O3, MgO and Nb2O5 oxides as raw materials according to the chemical general formula BaxCaySrzBikMg1 / 3Nb2 / 3O3 (wherein x, y, z and k are 0-1 mol%, and 2x + 2y + 2z + 3k = 2), the sintering temperature is lowered, and the problems that traditional ferroelectric ceramic is poor in thermal stability, low in dielectric constant, low in dielectric constant, low in dielectric constant and the like are effectively solved. And the breakdown strength is low. According to the prepared dielectric energy storage ceramic, at the high temperature of 270 DEG C, the electric breakdown strength reaches ultrahigh 700kV / cm, the energy storage density is 2.05 J / cm < 3 >, and the energy storage efficiency is 80.5%; the preparation method has the advantages of simple process, easily available raw materials and high production efficiency, and is suitable for large-scale actual production and application.

This invention relates to the field of relaxor ferroelectric ceramic dielectric energy storage materials, specifically to a sodium bismuth titanate-based relaxor ferroelectric ceramic and its preparation method, wherein the chemical composition of the sodium bismuth titanate-based relaxor ferroelectric ceramic is (1-x)BNLT. ‑x BAN, of which BNLT is 0.9Bi 0.5 Na 0.5 TiO3-0.1Bi 0.5 Li 0.5 TiO3, BAN is BaAl 0.5 Nb 0.5 The value of O3 and x ranges from 0.06 to 0.18. When x = 0.15, the ceramic exhibits excellent performance with a recoverable energy storage density (Wrec) of not less than 14.0 J / cm³ and an energy storage efficiency (η) of not less than 84% under an electric field of 775 kV / cm. This invention employs a solid-state reaction sintering process, which is simple to prepare and low in cost, making it suitable for high-performance energy storage capacitors in pulsed power systems.

The invention discloses a sodium niobate-based ferroelectric ceramic and a preparation method thereof, and belongs to the field of dielectric ceramics. The chemical composition general formula of the sodium niobate-based ferroelectric ceramic is (Na < 0.874-0.874 x > Yb < 0.0085-0.0085 x > Tm < 0.0085-0.0085 x > Bi < 0.075-0.75 x > Ba < 0.5 a > Sr < 0.5 b >) (Nb < 0.85-0.85 x > Ti < 0.15-0.15 x > Sn < 0.5 c > Hf < 0.5 d >) O3, a = b = c = d, and x is greater than or equal to 2 and less than or equal to 6; the ceramic is of an ABO3 type perovskite structure, and in the ABO3 type perovskite structure, Bi ions are in a compound occupation form in which the A site and the B site coexist. The preparation method comprises the following steps: (1) proportioning and refining to obtain mixed powder; (2) performing pre-synthesis and powder treatment to obtain uniform powder; (3) preparing a molded green body; (4) removing organic matters; and (5) densifying and sintering to obtain the ferroelectric ceramic. The sodium niobate-based ferroelectric ceramic provided by the invention can achieve the effects of high Wrec, high eta, wide temperature range and excellent stability at the same time.

The invention relates to the technical field of capacitors and preparation systems, and provides a lead-free positive dielectric adjustable antiferroelectric ceramic capacitor and a preparation system, a ceramic body adopts a lead-free raw material, harm is reduced, elements with smaller ion radiuses are doped into bismuth ferrite, a tolerance factor is reduced, the antiferroelectricity of the bismuth ferrite is stabilized, and the anti-ferroelectric performance of the capacitor is improved. The anti-ferroelectric stability of bismuth ferrite is improved, hysteresis is reduced, the anti-ferroelectric stability is improved, the corresponding preparation system of the lead-free forward dielectric adjustable anti-ferroelectric ceramic capacitor can improve the production continuity while forming adaptive production with a ceramic body, and the practicability is further enhanced. The ceramic body comprises a first component, a second component and a third component, the first component is a + 3 valence antiferroelectric stabilizer A, the second component is a paraelectric solid solution component, the third component is Mn3O4 and MnO2, the A is selected from rare earth elements such as Sm, La and Dy, the radius of the rare earth elements is smaller than that of Bi < 3 + >, and the paraelectric solid solution component comprises LnScO3, LnAlO3 and LnGaO3.

The invention belongs to the technical field of powder preparation by a wet chemical method, and provides a sodium bismuth titanate powder material and a preparation method thereof, the powder material is rhombohedral phase (Bi0. 5Na0. 5) TiO3, the particle morphology of the powder material is a nanocube, and the average size is 76nm. The (Bi0. 5Na0. 5) TiO3 nanocube is prepared through a two-step heating hydrothermal method, has the advantages of being simple in process, low in cost, good in stability and repeatability, capable of being produced on a large scale and the like, and has wide application prospects in the fields of sodium bismuth titanate, sodium bismuth titanate-based ferroelectric ceramics, barium titanate-based thermal sensitive ceramics and the like. The (Bi0. 5Na0. 5) TiO3 nanocube powder prepared by the invention is used as a raw material, (Bi0. 5Na0. 5) TiO3 ceramic sintered at 1100 DEG C for 4 hours has good sinterability and ferroelectricity, the relative density of the (Bi0. 5Na0. 5) TiO3 ceramic is 95% or above, and the maximum polarization intensity, the remanent polarization intensity and the coercive field of the (Bi0. 5Na0. 5) TiO3 ceramic are 40.02 mu C / cm < 2 >, 27.78 mu C / cm < 2 > and 87.5 kV / cm respectively.

The invention belongs to the field of solid electrolyte materials, and provides a PVDF-BST ceramic nanofiber composite solid electrolyte and a preparation method thereof.The PVDF-BST ceramic nanofiber composite solid electrolyte comprises a polyvinylidene fluoride (PVDF) polymer matrix and Ba0. 6Sr0. 4TiO3 (BST) ceramic nanofibers evenly dispersed in the matrix; the BST ceramic nanofiber is a ferroelectric ceramic fiber with a perovskite structure, the diameter of the BST ceramic nanofiber is 200-500nm, the filling proportion of the BST ceramic nanofiber is 2-10wt%, the PVDF matrix contains one or more lithium salts of LiClO4, LiPF6 or LiTFSI, and the thickness of the composite film is 50-100mu m; in the invention, the ionic conductivity is high, the interface stability is good, the material can be used for an all-solid-state lithium ion battery, the cycle performance and safety of the battery are obviously improved, and the preparation process is beneficial to industrialization.

The application discloses a hybrid unconventional ferroelectric ceramic material with a layered perovskite structure and a preparation method thereof. 1+x Ln 2‑x Sc2O7, Ln=Nd, Sm, Eu, one or more of them, 0.0 1.05 Nd 1.95 Sc2O7, Sr 1.1 Sm 1.9 Sc2O7, Sr 1.15 Eu 1.85 Sc2O7. The preparation method comprises the following steps: (a) according to the chemical formula Sr 1.05 Nd 1.95 Sc2O7, Sr 1.1 Sm 1.9 Sc2O7, Sr 1.15 Eu 1.85 Sc2O7, raw materials SrCO3, Nd2O3, Sm2O3, Eu2O3 and Sc2O3 are weighed, ball-milled, dried, sieved, and then calcined; (b) the powder prepared in the step (a) is sieved after secondary ball-milling; (c) the powder prepared in the step (b) is added with a binder, pressed into a tablet, sintered after plastic arrangement, and thus the ceramic material is prepared. Under the test conditions of room temperature, a test frequency of 2 Hz and a highest applied electric field of 400 kV / cm, the measured residual ferroelectric polarization value of the Sr 1.05 Nd 1.95 Sc2O7 ceramic is 0.9-1.1 muC / cm 2 , Sr 1.1 Sm 1.9 Sc2O7 ceramic is 2-3 muC / cm 2 , Sr 1.15 Eu 1.85 Sc2O7 ceramic is 0.5-0.75 muC / cm 2 .

The invention discloses pure-phase bismuth ferrite ceramic as well as a preparation method and application thereof, and belongs to the field of lead-free ferroelectric ceramic. Comprising the following steps: putting pure-phase bismuth ferrite precursor powder prepared by a hydrothermal method into a graphite mold, controlling the heating rate, heating to a sintering temperature, applying pressure, keeping the temperature, sintering, and finally preparing the pure-phase bismuth ferrite ceramic. According to the pure-phase bismuth ferrite ceramic prepared through SPS sintering, volatilization of Bi < 3 + > and generation of impure phases are effectively inhibited. The bismuth ferrite ceramic shows good magnetic performance, the magnetic performance is enhanced, good dielectric stability is shown, and the bismuth ferrite ceramic has certain ferroelectricity and good energy storage performance. Aiming at the problems that pure-phase bismuth ferrite ceramic is difficult to prepare by a traditional solid-phase reaction method, a mixed phase is generated due to Bi < 3 + > volatilization and oxygen vacancy defects caused by high-temperature sintering, multiferroic performance is unstable and the like, the preparation process of the bismuth ferrite ceramic is optimized by adopting a mode of combining a hydrothermal method and spark plasma sintering (SPS).