95results about How to "Improve piezoelectric performance" patented technology

The invention discloses a nanoparticle / polyvinylidene fluoride composite piezoelectric gain photocatalytic antibacterial film and a preparation method and application thereof.The preparation method comprises the steps that a polyvinylidene fluoride solution serves as a core layer spinning solution, and photocatalytic nano sol serves as a skin layer spinning solution; and carrying out coaxial electrostatic spinning on the polyvinylidene fluoride solution and the photocatalytic nano sol to prepare the nano particle / polyvinylidene fluoride composite piezoelectric gain photocatalytic antibacterial film. According to the preparation method disclosed by the invention, nano-scale photocatalytic sol is fixed on the surface of micron-scale polyvinylidene fluoride in one step by utilizing an electrostatic spinning technology, so that the polyvinylidene fluoride is prevented from coating effective components, and the effective components are also prevented from blocking holes of polyvinylidene fluoride fibers; effective separation and directional migration of electrons and holes of sol on the surface are effectively promoted, and the capacity of photocatalytic nano sol for removing biological aerosol is improved. The preparation method is simple in industry, low in energy consumption and easy for large-scale production.

The invention discloses an invisible appliance based on a transparent piezoelectric film and a design method thereof. A perioral muscle pressure sensor is installed on the lip / cheek lingual surface of teeth of the invisible orthodontic appliance, an occlusal force sensor is installed on the occlusal surface, and a tooth surface counter-acting force sensor is installed on the inner side tissue surface, so that dynamic changes of perioral muscle pressure, occlusal force and orthodontic force can be monitored in real time. The invisible orthodontic appliance provided by the invention integrates a sensor with high piezoelectric coefficient and high flexibility, has high sensitivity and accuracy, can be used for testing dynamic changes of orthodontic mechanics and evaluating the influence of perioral muscle pressure, occlusal force and the like on treatment during physiological processes of chewing, breathing, swallowing, language and the like of a patient; a doctor optimizes an orthodontic scheme through the PC terminal and pays attention to the association between oral functional mechanics and malocclusion, bad oral habits, bruxism, temporomandibular joint disorder and other diseases, and the efficiency and accuracy of oral health management are improved.

The invention discloses a preparation method of a polyvinylidene fluoride-based polymer piezoelectric film, which comprises the following steps: S1, adding a poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer and a poly (vinylidene fluoride-trifluoroethylene) binary copolymer into a solvent, and uniformly mixing to obtain a mixed solution; and S2, drying the mixed solution obtained in the step S1 to obtain a polymer blend membrane, and performing combination and treatment on the blend membrane to obtain a membrane sample. The preparation method comprises the following steps: carrying out solution blending on a poly (vinylidene fluoride-trifluoroethylene-chlorofluoroethylene) terpolymer and a poly (vinylidene fluoride-trifluoroethylene) biopolymer as raw materials, controlling the mixing ratio of the two polymers, and carrying out post-treatment matching combination to prepare the polyvinylidene fluoride-based polymer piezoelectric film with high piezoelectric property.

The invention discloses a barium titanate-based leadless piezoelectric ceramic material and a preparation method and application thereof, and relates to the technical field of functional materials, the chemical formula of the barium titanate-based leadless piezoelectric ceramic material is Ba0. 9Sr0. 1Ti1-xSnxO3, x = 0-0.10, and x represents a mole fraction. By regulating and controlling the concentration of Sn ions in the BT-based lead-free piezoelectric ceramic, a multiphase structure with flat free energy is formed near the room temperature, meanwhile, an unconventional short-range disorderly-arranged polar snow-mud-state domain structure is induced, an extremely good domain change dynamic behavior is shown under the action of an external field, and the piezoelectric ceramic is prepared. Meanwhile, excellent piezoelectric property, electrostrictive property, electrocaloric property and mechanical property are obtained, and a candidate material is provided for a new generation of multifunctional high-precision electronic information devices.

The invention belongs to the technical field of biomedical materials, and discloses an intervertebral disc repair material based on an intervertebral disc degeneration staged treatment strategy as well as a preparation method and application of the intervertebral disc repair material. The intervertebral disc repair material comprises a sandwich-structure dual-electroactive stent and composite hydrogel attached to the dual-electroactive stent, the double-electroactive stent with the sandwich structure comprises a conductive porous stent with a conductive through pore channel structure and piezoelectric fiber films positioned on the upper side and the lower side of the conductive porous stent; the composite hydrogel comprises hydrogel and antioxidant nano enzyme uniformly dispersed in the hydrogel; the antioxidant nano-enzyme is a core-shell structure nano-particle with Co-Ni bimetallic oxide as a core and polydopamine as a shell. The degeneration early intervertebral disc is repaired through the antioxidant and anti-inflammatory nano-enzyme, the defective intervertebral disc after resection is repaired through the double electroactive scaffolds, and the electroactive scaffold enhanced composite hydrogel can replace the degeneration later intervertebral disc, so that corresponding treatment is achieved for different stages of intervertebral disc degeneration.

The invention provides a self-biased very-low-frequency mechanical transmitting antenna driven by piezoelectricity and a preparation method of the self-biased very-low-frequency mechanical transmitting antenna. The preparation method comprises the following steps: step 1, preparing a piezoelectric ceramic material; step 2, cutting and slotting; thirdly, resin is poured; step 4, cutting the layer sheets; step 5, packaging; step 6, polarization treatment; step 7, preparing a bonding layer; and 8, hot-pressing and compounding. Compared with an existing magnetoelectric antenna, the self-biased very-low-frequency mechanical transmitting antenna has the advantages of being self-biased, high in piezoelectric property, miniaturized, free of extra noise sources and electromagnetic interference and the like, has the advantages of being high in stress transmission efficiency, small in ohmic loss and the like, can meet the requirement for miniaturization of the magnetoelectric mechanical antenna, is easy to form a large-scale array, and is suitable for large-scale popularization and application. The magnetic emission performance under zero bias is improved, and the low-frequency communication effect is achieved.

The invention relates to the field of piezoelectric ceramic materials, in particular to BNT-based leadless piezoelectric ceramic and a preparation method thereof.The BNT-based leadless piezoelectric ceramic has the chemical structural general formula as follows: (1-y-z) Bi1 / 2Na1 / 2Ti1-x (M1 / 3V2 / 3) xO3-yNdAlO3-zLiTaO3, M is a divalent metal element, x is larger than 0 and smaller than or equal to 0.015, y is larger than or equal to 0.01 and smaller than or equal to 0.05, z is larger than or equal to 0.01 and smaller than or equal to 0.05, and it can be known through tests that the BNT-based leadless piezoelectric ceramic prepared through the method has excellent piezoelectric performance and can be applied to the field of piezoelectric ceramics. The method has wide application prospects in the fields of pressure sensors, acceleration sensors, sonic sensors and the like.

The invention discloses biological piezoelectric ceramic as well as a preparation method and application thereof, and belongs to the field of implantable and biodegradable sensor materials. A biological ceramic material hydroxyapatite (HA) and a lead-free piezoelectric ceramic material sodium bismuth titanate (BNT) are compounded, the obtained HA / BNT biological piezoelectric ceramic shows remarkable biodegradability and certain piezoelectric property, and a certain amount of potassium and lithium ions are further doped in BNT, so that the biodegradability of the HA / BNT biological piezoelectric ceramic is improved, and the biodegradability of the HA / BNT biological piezoelectric ceramic is improved. The obtained HA / BNKLT biological piezoelectric ceramic also shows remarkable biodegradability and certain piezoelectric property, and the two kinds of biological piezoelectric ceramics can meet the self-power supply requirement of an implantable biodegradable sensor. In addition, the biological piezoelectric ceramic provided by the invention can avoid the potential toxicity problem caused by barium ions and niobium ions in the prior art.

The invention provides a preparation method of a stretchable piezoelectric sensor based on oriented PVDF fiber, and relates to the technical field of intelligent sensors, the piezoelectric sensor comprises a packaging layer, a positive TPU film layer, a negative TPU film layer and a PVDF piezoelectric film, the outer surface of the positive TPU film layer and the outer surface of the negative TPU film layer are provided with carbon nanotube particles, and the PVDF piezoelectric film is arranged on the outer surface of the packaging layer. The packaging layer is located on the outer surface of the positive electrode TPU film layer, the outer surface of the negative electrode TPU film layer and the outer surface of the PVDF piezoelectric film. According to the preparation method of the stretchable piezoelectric sensor based on the oriented PVDF fibers, the PVDF nanofiber film with the oriented fiber characteristics is prepared through the electrostatic spinning technology; the PVDF piezoelectric film with high piezoelectric property and high stretchability is obtained by regulating and controlling electrostatic spinning process parameters, the film has high stability and shows good mechanical property through testing, meanwhile, after the film is packaged into a sensor, the open-circuit voltage under different elongation rates is stable through testing, and the mechanical strain of different surface characteristics can be effectively detected.

The invention discloses a design and manufacturing method of a diaphragm for a high-safety quick-charge type lithium battery, and the preparation method of the diaphragm comprises the following steps: adding mesocrystal anatase type TiO2, an MX2 type semiconductor nanomaterial and PVDF (Polyvinylidene Fluoride) into a polar solvent according to a molar ratio of (0.3-0.7): (0.2-0.5): (1.5-1.9), sequentially stirring at normal temperature, carrying out ultrasonic treatment, casting a mixed solution on an ITO (Indium Tin Oxide) conductive glass substrate, and carrying out vacuum drying to obtain the diaphragm for the high-safety quick-charge type lithium battery. The preparation method comprises the following steps: adding PVDF (Polyvinylidene Fluoride) into a reaction kettle, carrying out vacuum drying at 60-80 DEG C to form a TiO2-MX2-PVDF composite film, then spraying metal on the surface of the film, and finally carrying out polarization treatment on the metal-sprayed composite film with the applied voltage range of 3-9V and the frequency of 3-5mS to prepare the TiO2-MX2-PVDF composite diaphragm with the beta phase as the main component. According to the invention, the PVDF diaphragm is modified by using mesocrystal anatase TiO2 and MoS2 nano materials, so that the piezoelectric property of the PVDF diaphragm is remarkably improved, and a certain reverse overpotential is generated at the interface of the negative electrode and the diaphragm in combination with the stress generated by expansion of the silicon-based negative electrode in the silicon-based lithium ion battery, so that the risk of lithium precipitation at the interface of the negative electrode under fast charging is effectively inhibited, and the safety and the service life of the battery are remarkably improved.

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.

A piezoelectric ceramic and its preparation method and application, which mainly relate to the field of piezoelectric ceramics. This method is different from the two-step sintering process of the traditional sintering process. By effectively controlling the changes in the sintering temperature and the holding time and the formula of the raw materials, the densification sintering of lead-free piezoelectric ceramics is achieved; the piezoelectric ceramic preparation method provided by the present application reduces the volatilization of alkali metal elements such as K and Na at high temperatures, which is conducive to the stability of the stoichiometric ratio of the formula and reduces the generation of impurities, thereby improving the density and process stability of the ceramics; the piezoelectric ceramics of the present application have high piezoelectric properties, density and mechanical properties, and are also environmentally friendly; the piezoelectric ceramics provided by the present invention have broad application prospects and can be applied to the optical fiber scanner in the field of laser display and configured as an actuating part. The actuating part uses the inverse piezoelectric effect of the piezoelectric ceramic to control the optical fiber on the actuating part to vibrate and scan, thereby realizing laser scanning imaging.

The invention discloses a piezoelectric nanomaterial for triggering mitochondrial fusion and a preparation method and application thereof, and belongs to the technical field of biology, and the piezoelectric nanomaterial provided by the invention can supplement electron depolarization mitochondrial membrane potential (delta psi) in a targeted manner under ultrasonic stimulation. The depolarization of the delta psi significantly promotes the mitochondrial fusion and inhibits the fission of the mitochondrial by activating mechanisms such as long optic nerve atrophy 1 (OPA1) and calcium ion influx, so that mitochondrial fusion proteins mitofusin 1 (Mfn1) and mitofusin 2 (Mfn2) are activated, the recruitment of dynamic protein related protein 1 (Drp1) is inhibited, the expression of mitochondrial fission protein 1 (Fis1) is reduced, and a JC-1 dye evaluates the delta psi, so that the depolarization of the delta psi is realized. The observed mitochondrial dynamic change is in positive correlation, the mitochondrial fusion is regulated by using the nano material, and a new method is provided for targeting tumor metabolism and improving cancer treatment results.

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 embodiment of the present invention discloses a textured one-dimensional all-inorganic lead-based halogen perovskite polymer composite fiber, a piezoelectric device and a preparation method; the preparation method comprises: mixing a Cs source, a Pb source, a polymer, a ligand and an organic solution to prepare a precursor solution; wherein the Cs source is CsX, the Pb source is PbX2, wherein X is any one of Cl, Br and I; the polymer is any one of polyvinylidene fluoride, polystyrene and polymethyl methacrylate; the ligand is any combination of oleic acid and oleylamine; the organic solution is N,N-dimethyl Any combination of methylformamide and dimethyl sulfoxide; in the precursor solution, the mass ratio of Cs source and Pb source to the precursor solution is 4-20%, the mass ratio of oleylamine and oleic acid to the precursor solution is 3-12%, and the mass ratio of polymer to the precursor solution is 4-16%; the precursor solution is subjected to an electrospinning process to obtain a textured one-dimensional CsPbX3 / polymer composite fiber; wherein the electrospinning voltage is set to 10-20 kV, the temperature is set to 20-80°C, and the speed of the collecting drum is set to 100-1000 r / min.

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.

The invention discloses a preparation method of a poly (vinylidene fluoride-trifluoroethylene) electrostatic spinning piezoelectric film. The preparation method comprises the following steps: annealing and regulating the content of oriented amorphous components of a poly (vinylidene fluoride-trifluoroethylene) film; the content of an oriented amorphous region in the piezoelectric film after annealing treatment is greatly increased; the remanent polarization is improved by increasing the content of the oriented amorphous region. According to the electrostatic spinning piezoelectric film, poly (vinylidene fluoride-trifluoroethylene) serves as an object, lamellar crystal orientation and defects are induced through a drawing force field generated under the electrostatic spinning technology, generation of oriented amorphous components of different structures is promoted in limited lamellar crystals in cooperation with later annealing treatment, and the electrostatic spinning piezoelectric film with the high piezoelectric performance 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.

The invention discloses a paper-based piezoelectric nano-generator and a preparation method thereof, and belongs to the technical field of nano-generators, the paper-based piezoelectric nano-generator is characterized in that BCZT ceramic particles with different crystal phases are prepared through a solid phase method, and then a first-layer film and a second-layer composite film are prepared through layer-by-layer tape casting and scraper height regulation and control methods. Compared with a one-layer film only containing one crystal phase, in the two-layer composite film containing two different crystal phases, two crystal phase BCZT ceramic particles are co-doped, so that the piezoelectric nano generator has two working modes of d33 and d31, and in the two-layer composite film, a three-dimensional hydrogen bond engineering strategy established between layers enables the two-layer composite film to have better mechanical properties. Different working modes and higher mechanical properties are combined, so that the piezoelectric nano generator prepared from the two layers of composite films can be used in a harsh mechanical environment.

The invention relates to a preparation method and application of a biomass charcoal / PDMS composite material with piezoelectric characteristics, and the preparation method comprises the following steps: taking biomass as a raw material, carrying out gelation reaction at low temperature, and then carrying out bidirectional freezing treatment to obtain an ordered three-dimensional body structure of at least centimeter level; and carrying out freeze drying treatment on the obtained three-dimensional body structure to obtain the collagen aerogel. The collagen aerogel is subjected to high-temperature treatment in a protective atmosphere, biomass carbon aerogel is obtained, and the treatment temperature is 800-1600 DEG C; dissolving a PDMS prepolymer in an ethyl acetate solvent to form a PDMS prepolymer solution, wherein the volume ratio of the PDMS prepolymer to the ethyl acetate solvent is 1: (0.5-10); and completely immersing the obtained biomass charcoal aerogel in the PDMS prepolymer solution, dipping for 10-60 minutes, then putting into a drying oven, and carrying out curing reaction at the temperature of 50-80 DEG C, so as to finally obtain the biomass charcoal / PDMS composite material. According to the composite material, the piezoelectric sensitivity and the response speed of the composite material are improved through interface interaction and a stress transfer mechanism.

The present invention belongs to the field of piezoelectric catalysis technology, and specifically relates to an adenine / SDBS / UiO-66 composite catalyst, a preparation method and an application thereof. Adenine / UiO-66 (AD-U) material was synthesized by adding a connecting agent adenine, and then a surfactant (sodium dodecylbenzene sulfonate, SDBS) was introduced to prepare an adenine / SDBS / UiO-66 (AD-U-S) composite material. The optimized AD-U-S catalyst has an efficiency of up to 98% in degrading DCF in 30 minutes, which is 20 minutes earlier than the AD-U catalyst. Therefore, the AD-U-S catalyst has better piezoelectric response performance, a larger specific surface area and a higher charge transfer efficiency. The preparation conditions of the present invention are easy to control, environmentally friendly, simple in process, and good in operability. The obtained material has the characteristics of high catalytic efficiency, low energy consumption, high stability, and no secondary pollution.

The utility model relates to a double-helix type piezoelectric composite material structure, which comprises an upper electrode, a lower electrode, a polymer phase and a piezoelectric ceramic phase, and particularly, the piezoelectric ceramic phase is of a double-helix structure, and the piezoelectric ceramic phase and the polymer phase are alternately distributed at intervals. According to the utility model, the conventional piezoelectric ceramic phase arrangement mode is changed, and the piezoelectric ceramic phase is designed into a double-helix structure, so that the sound field directivity of the transducer is effectively improved, and meanwhile, under the limitation of the width, the electromechanical coupling coefficient, piezoelectric property and the like of a composite material as well as the sensitivity, bandwidth and the like of the transducer can be improved; the formed 2-2 and 1-3 type piezoelectric composite material structures effectively suppress crosstalk of transverse vibration, reduce energy loss generated by transverse coupling motion, enable a thickness vibration mode to be purer, and meet performance requirements of sensor elements with different functions.

The invention discloses a bismuth layered sodium bismuth titanate high-temperature piezoelectric ceramic material and a preparation method and application thereof, the general formula of the bismuth layered sodium bismuth titanate high-temperature piezoelectric ceramic material is Na < 0.5 > Bi < 4.5 > Ti < 4-x > Nb < x > O < 15 + x / 2 >: Sr, the ratio of Sr to Na < 0.5 > Bi < 4.5 > Ti < 4-x > Nb < x > O < 15 + x / 2 > is 0.02: 1, and x is more than or equal to 0.04 and less than or equal to 0.08. The dielectric loss of the bismuth layered sodium bismuth titanate high-temperature piezoelectric ceramic material is 0.0037, the Curie temperature is 669 DEG C, the piezoelectric constant is 31.5 pC / N, the mechanical quality factor Qm is 3576, the electromechanical coupling coefficient kp is 15.2%, and the high-temperature resistivity at 500 DEG C is 5.7 * 10 < 7 > omega.cm. The bismuth layered sodium bismuth titanate high-temperature piezoelectric ceramic material has a wide application prospect in the field of high-temperature piezoelectric devices.

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 provides a piezoelectric laminated body and a piezoelectric element. The piezoelectric laminated body has high piezoelectric performance and higher reliability compared with the prior art when provided with a seed layer. The piezoelectric laminate and the piezoelectric element are sequentially provided with a lower electrode layer, a seed crystal layer and a piezoelectric film on a substrate, the piezoelectric film is mainly composed of a first perovskite oxide containing Pb, Zr, Ti and Nb, and the seed crystal layer is mainly composed of a second perovskite oxide lattice-matched with the first perovskite oxide. The piezoelectric film has a proportion of crystal grains having a grain size of 100 nm or less in a crystal grain size distribution obtained by electron backscatter diffraction of 15% or less, and satisfies Ec + + Ec < Ec +-Ec-55 kV / cm < = Ec + < = 75 kV / cm, and 75 kV / cm < = Ec +-Ec < = 100 kV / cm, where Ec + is a positive-side coercive field and Ec-is a negative-side coercive field in polarization-electric field characteristics.

The invention relates to the field of piezoelectric ceramic materials, and in particular to a method for preparing a potassium sodium niobate-based lead-free piezoelectric ceramic. A two-step molten salt method is adopted to synthesize a KNN prefabricated powder, the KNN prefabricated powder, a BNT prefabricated powder and a LS prefabricated powder are mixed and ball-milled and dried, a binder is added to granulate, sieve and press to obtain a green body, the green body is heated to 500-600 DEG C in a first stage, kept warm for debinding for 1-5 hours, and then heated to 1000-1150 DEG C in a second stage, kept warm for sintering for 1-5 hours. The potassium sodium niobate-based lead-free piezoelectric ceramic prepared by the invention has excellent piezoelectric properties and can meet the application requirements of small components, precision instrument control and other equipment.

The invention relates to the field of piezoelectric ceramic materials, in particular to a preparation method of potassium-sodium niobate-based lead-free piezoelectric ceramic, which comprises the following steps: synthesizing KNN prefabricated powder by adopting a two-step molten salt method, mixing, ball-milling and drying the KNN prefabricated powder, BNT prefabricated powder and LS prefabricated powder, adding a binder, granulating, sieving, pressing to obtain a green body, heating the green body to 500-600 DEG C in the first stage, keeping the temperature and discharging glue for 1-5 hours, and cooling to room temperature to obtain the potassium-sodium niobate-based lead-free piezoelectric ceramic. The potassium-sodium niobate-based leadless piezoelectric ceramic prepared by the preparation method disclosed by the invention has excellent piezoelectric property, and can meet the application requirements of equipment such as small-sized components, precise instrument control and the like.

The invention relates to a PZT-based piezoelectric ceramic, a preparation method thereof and a piezoelectric device. The chemical general formula of the PZT-based piezoelectric ceramic is as follows: 0.35 Pb (Ni < 1 / 3 > Nb < 2 / 3 >) O < 3 >-0.26 Pb < 0.92 > Ba < 0.04 > Sr < 0.04 > ZrO < 3 >-0.39 Pb < 0.92 > Ba < 0.04 > Sr < 0.04 > TiO < 3 >. According to the PZT-based piezoelectric ceramic provided by the technical scheme of the invention, PZT is taken as a matrix, and PNN is introduced as a third component, so that the piezoelectric property of pure PZT is improved. Experiments prove that the piezoelectric coefficient d33 of the PZT-based piezoelectric ceramic can reach 1182pC / N, and the PZT-based piezoelectric ceramic is beneficial to wide application. In addition, the invention also relates to a preparation method of the PZT-based piezoelectric ceramic, and a piezoelectric device comprising the PZT-based piezoelectric ceramic or the PZT-based piezoelectric ceramic prepared by any one of the preparation methods of the PZT-based piezoelectric ceramic.