16results about How to "Improve piezoelectric performance" patented technology

High-performance P(VDF-TrFE) based composite film and preparation method thereof, and nanogenerator containing the composite film, the present application relates to piezoelectric composite material technical field, specifically relates to a kind of P(VDF-TrFE) / ZnO / CMWCNTs composite film and preparation method thereof, and piezoelectricity / friction electricity nanogenerator containing the composite film;The composite film is P(VDF-TrFE) / ZnO / CMWCNTs composite film, with P(VDF-TrFE) copolymer mass as benchmark, the addition amount of each component is as follows: P(VDF-TrFE) copolymer: TrFE molar content is 30%;ZnO nanoparticles: mass fraction is 0.36~1.80%;CMWCNTs: mass fraction is 0.01~0.03%;Overcome the technical defects, such as filler ratio out of control in existing P(VDF-TrFE) composite system, process parameter is not clear, piezoelectric property is low, and the output performance of nanogenerator based on it is poor, and stability is insufficient.

This application provides a high-voltage electrochemical composite hydrogel for wound skin repair and its preparation method. The high-voltage electrochemical composite hydrogel is prepared by using hydroxyethyl cellulose and acrylamide monomers as raw materials to form an interpenetrating network structure. Polyvinylidene fluoride (PVDF) and ZnO nanowires are used as piezoelectric materials, and are formed by interweaving PVDF and ZnO nanowires within the hydrogel. This high-voltage electrochemical composite hydrogel significantly improves the crystallization orientation and polarization efficiency of PVDF through mechanical stretching and polarization, resulting in an order-of-magnitude improvement in the piezoelectric properties of the composite hydrogel. Simultaneously, it retains the excellent flexibility and biocompatibility of the hydrogel, showing broad application prospects in flexible sensors, self-powered devices, and human-computer interfaces.

The invention discloses a texture preparation method for high-performance lead-free piezoelectric ceramics of bismuth ferrite-barium titanate. The general formula of the ceramic composition is as follows, where the molar fraction ratio of BiFeO3 and BaTiO3 is 2:1, x, y, t, and m all represent molar fractions, and 0 < x ≤ 0.05, 0 < y ≤ 0.05, 0 < t ≤ 0.05, 0 < m ≤ 0.05. In the sintering stage of the invention, a temperature gradient field is constructed to make the ceramic grains grow texture-directionally, and a textured piezoelectric ceramic with a piezoelectric constant d 33 reaching above 1000 pC / N at 350 °C and a T dr reaching above 350 °C is obtained. The preparation process of the invention is simple, and the prepared ceramic has excellent high-temperature performance and can be applied to the field of high-temperature piezoelectricity.

The application discloses a PZT-based textured piezoelectric ceramic and a phase transition assisted polarization preparation method and application thereof, and belongs to the technical field of piezoelectric materials. The preparation method comprises the following steps: preparing PMeN-PZT matrix powder; preparing a textured piezoelectric ceramic; and sequentially polishing the textured piezoelectric ceramic, sintering silver electrodes and performing phase transition assisted polarization to obtain the PZT-based textured piezoelectric ceramic; wherein the phase transition assisted polarization step is: heating the textured piezoelectric ceramic after sintering silver electrodes to a polarization temperature, the polarization temperature is higher than the trigonal-tetragonal phase transition temperature and lower than the Curie temperature, and the polarization is performed under a polarization electric field of 300 V / mm-1000 V / mm, then the polarization is naturally cooled to room temperature, and the electric field is removed. The technical problems of low piezoelectric / electromechanical / dielectric performance caused by insufficient polarization in traditional heating polarization and the technical problem that piezoelectric materials are difficult to have high piezoelectric performance and high Curie temperature at the same time are solved.

The invention provides piezoelectric ceramic which is obtained by replacing Bi < 3 + > in Bi4Ti3O12 with Nd < 3 + > and replacing Ti < 4 + > in Bi4Ti3O12 with W < 6 + >. The structural formula of the piezoelectric ceramic is Bi < 4-x > Nd < x > Ti < 2.925 > W < 0.075 > O < 12 >, wherein x is greater than or equal to 0.01 and less than or equal to 0.05. The invention also provides a preparation method and application of the piezoelectric ceramic. Nd < 3 + > with smaller ion radius is introduced to replace Bi < 3 + >, and W < 6 + > is combined to replace Ti < 4 + >, so that the crystal structure of the ceramic can be finely adjusted, and the electrical property of the ceramic can be improved. Nd doping has great influence on the microstructure and macroscopic performance of the ceramic. Preferably, when x is equal to 0.03, the piezoelectric ceramic with very high piezoelectric property and resistivity is obtained.

This invention relates to the field of piezoelectric materials technology, specifically to a chiral nitrogen-containing heterocyclic organic crystalline piezoelectric material and its preparation method. The organic crystalline piezoelectric material is N-cyanoethyl-( S )-2-methylpiperazine hydrochloride, whose core is a one-dimensional hydrogen-bonded chain construction strategy of unilaterally protonated chiral piperazine, with protonated N-cyanoethyl-( S Using 2-methylpiperazine cations as structural building blocks and chloride ions as charge balancers, a highly oriented one-dimensional hydrogen bond chain is constructed by regulating intermolecular hydrogen bonding. This enhances the ordered arrangement of molecular dipoles and optimizes the synergistic mode of lattice strain-polarization response, achieving a breakthrough in piezoelectric properties. The material exhibits a piezoelectric coefficient as high as ±80 pC / N and an electromechanical coupling coefficient as high as 0.35, far exceeding known chiral organic piezoelectric materials. Furthermore, it demonstrates excellent thermal stability and can be widely applied in demanding applications such as micro-pressure sensors, low-frequency vibration detectors, and micro energy harvesters.

This invention relates to the field of piezoelectric ceramics technology, and in particular to a composite ion-modified bismuth layered bismuth titanate calcium-based high-temperature piezoelectric ceramic and its preparation method. The general formula for high-temperature piezoelectric ceramics is: Ca 1‑x (LiCe) x / 2 Bi 3.75 Nd 0.25 Ti 3.935 Sc 0.065 O 15 , where x is a complex high-valence ion (LiCe). 4+ Twice the molar amount, x = 0.02, 0.05, 0.08, 0.10. This invention employs the above-mentioned composite ion-modified bismuth layered bismuth titanate calcium-based high-temperature piezoelectric ceramic and its preparation method to meet the application requirements in high-temperature environments while ensuring the material's environmental friendliness.

The invention discloses a preparation method of a catalyst for producing hydrogen peroxide through oxygen deficiency tandem piezoelectric-mechanical redox, and the preparation process of the catalyst comprises the following steps: firstly, constructing a zinc oxide substrate with a litchi-shaped structure through a water-phase thermally-induced self-assembly reaction; then introducing oxygen defects with controllable content on the surface of zinc oxide by adopting a liquid-phase mediated chemical reduction mode; and finally, performing in-situ auto-polymerization on the surface of the defective zinc oxide to form a polydopamine coating, thereby obtaining the target catalyst. The catalyst can efficiently and highly selectively prepare hydrogen peroxide through ultrasonic excitation under the conditions of pure water and normal temperature, has the advantages of mild reaction conditions, high generation rate, good stability, environmental protection and the like, and is suitable for the application scene of distributed hydrogen peroxide in-situ preparation.

The application discloses a high-temperature-resistant and corrosion-resistant full-temperature-range measuring ceramic temperature sensor and a preparation method thereof, and belongs to the technical field of temperature sensors.The high-temperature-resistant and corrosion-resistant full-temperature-range measuring ceramic temperature sensor comprises an ultrasonic sensing ceramic rod, one end of the ultrasonic sensing ceramic rod is sequentially provided with a crystallization orientation induction layer, a piezoelectric functional layer, a protective layer and a high-temperature-resistant electrode layer from inside to outside, and the piezoelectric functional layer is a (002) oriented columnar crystal AlScCrN coating.The application has the beneficial effect that the ceramic material is applied to temperature detection as a temperature sensor, the shortcomings that a traditional thermocouple has a slow response speed and cannot work in a corrosive environment are avoided, the ceramic temperature sensor can work from a low temperature of liquid nitrogen to a high temperature of 2500 DEG C, and the temperature measurement in a wide temperature range is realized for the first time.

This invention discloses a GTR membrane, its preparation method, and its application, belonging to the field of biomedical materials technology, and solves the problem of insufficient antibacterial effect of existing GTR membranes. The method includes the following steps: uniformly dispersing BaTiO3 in a Tris buffer solution; dissolving dopamine hydrochloride powder in the reaction system; stirring evenly; centrifuging to collect the precipitate; cleaning and drying to obtain PDA@BaTiO3 nanoparticles; adding the PDA@BaTiO3 nanoparticles to a silver ammonia solution; stirring at room temperature; centrifuging to collect the precipitate; cleaning and drying to obtain Ag@PDA@BaTiO3 particles; uniformly dispersing the Ag@PDA@BaTiO3 particles in a hexafluoroisopropanol solution of L-polylactic acid; electrospinning the reaction system to obtain a fiber membrane; and sequentially subjecting the membrane to ventilation, high-temperature annealing, and natural cooling to room temperature to obtain the GTR membrane. The GTR membrane provided by this invention possesses both piezoelectric and photothermal effects, exhibits rapid sterilization and long-lasting antibacterial activity, and has a simple preparation process.

The invention provides a two-dimensional heterojunction piezoelectric material for water treatment and a preparation method thereof, and belongs to the technical field of water treatment. The two-dimensional heterojunction piezoelectric material has a heterojunction structure formed by cobalt sulfide and molybdenum disulfide, and molybdenum disulfide has a 1T crystal phase and a 2H crystal phase. The two-dimensional heterojunction piezoelectric material has good conductivity, charge separation efficiency and stability, when the two-dimensional heterojunction piezoelectric material is applied to water treatment, the two-dimensional heterojunction piezoelectric material generates surface charges under the action of mechanical force and catalyzes and degrades various organic pollutants in water, application is flexible, and environmental adaptability is high.

The application discloses KNN-based lead-free piezoelectric ceramics and a preparation method and application thereof, and belongs to the technical field of piezoelectric ceramics. 0.52 Na 0.48 ) （1‑a‑b） Ce a Li b Nb （1‑c） Ta c O3, wherein 0.005<=a<=0.02, 0.01<=b<=0.08; 0.01<=c<=0.1; a sintering aid is added to the KNN-based lead-free piezoelectric ceramic, and the sintering aid is a niobium borate-based glass powder. The three elements Li, Ta and Ce are cooperatively doped, and the electromechanical coupling coefficient is significantly improved; the Ce element is doped into the piezoelectric ceramic matrix to avoid local composition segregation, compensate the temperature coefficient, and inhibit the lattice mutation caused by the phase transition near the Curie temperature; the piezoelectric performance of the piezoelectric ceramic material can be improved, and the temperature stability of the piezoelectric ceramic can also be improved.

The application discloses a piezoelectric fuel cell and application thereof. The electrode of the application comprises a conductive substrate and a catalytic film fixed on the conductive substrate material, and the catalytic film comprises granular tetragonal phase BaTiO3, has good piezoelectric performance, strong active material loading firmness, simple preparation, low cost and other advantages, and can fully utilize mechanical energy and organic wastewater in the environment when used in the fuel cell, so that stable power generation and degradation of organic pollutants are simultaneously realized. Meanwhile, the tetragonal phase BaTiO3 of the catalytic film on the electrode of the application can improve the conductive performance and piezoelectric performance of the electrode by loading SnO2 or doped SnO2, and the electrode loaded with SnO2 or doped with SnO2 also has good piezoelectric performance, strong active material loading firmness, and simultaneously realizes stable power generation and effective degradation of organic pollutants, and is suitable for the fields of environmental protection and energy.

The invention relates to a metal halide piezoelectric body / P (VDF-TrFE) composite piezoelectric nanofiber, which is characterized in that nanocrystalline is formed in situ in a P (VDF-TrFE) matrix by using a metal halide piezoelectric body, and formation of a P (VDF-TrFE) polar beta phase is induced. A metal halide piezoelectric body and P (VDF-TrFE) are jointly dissolved in an organic solvent, nanofibers are prepared in one step through an electrostatic spinning method, nanocrystals grow in situ in a polymer through the metal halide piezoelectric body, and the P (VDF-TrFE) is jointly promoted to form a polar beta phase under the uniaxial stretching effect of the electrostatic spinning process. The polymer nano composite material has high piezoelectric property and high flexibility, and the preparation method has the advantages of simplicity and rapidness in operation, low energy consumption and the like.

This invention discloses a barium titanate-based piezoelectric ceramic with high temperature stability and its preparation method. The ceramic has the following characteristics: Ba 1‑x Ca x Ti 1‑y Zr y O3, 0.17≤x≤0.19, 0.11≤y≤0.13. The ceramic uses BaTiO3 as the basic research system. By replacing some barium ions with calcium ions and some titanium ions with zirconium ions, the phase transition temperature of barium titanate is adjusted, so that it maintains stable piezoelectric properties over a wider temperature range, i.e., it has high temperature stability. Furthermore, by doping with calcium and zirconium sources to change the morphology and distribution of electric domains, the piezoelectric coefficient of the ceramic is increased.

The present application relates to a kind of PZT-based piezoelectric ceramic material with large electric strain under low electric field and high Curie temperature and its preparation method.The chemical composition of the PZT-based piezoelectric ceramic material is: Pb 1‑2n‑1.5x La x Sr n Ba n (Zr y Ti 1‑y )O3-zwt%Sn, wherein 0.004≤x≤0.007, 0.52≤y≤0.6, 0.3≤z≤0.7, 0.01≤n≤0.04.The preparation method of the PZT-based piezoelectric ceramic material includes the following steps: (1) batching; (2) calcination; (3) granulation; (4) plastic, sintering.