24results about How to "High piezoelectric coefficient" patented technology

The invention relates to a bismuth scandate-lead titanate based piezoelectric ceramic material and a preparation method and application thereof, the chemical general formula of the bismuth scandate-lead titanate based piezoelectric ceramic material is (1-y) Bi (Sc (1-x) Mex) O3-yPbTiO3, Me is a late transition metal element, x is 0.03-0.3, and y is 0.63-0.64. Compared with the prior art, the piezoelectric anisotropy and the piezoelectric property of the piezoelectric ceramic are improved by doping the rear transition group metal element Me on the basis of the BiScO3-PbTiO3 binary system piezoelectric ceramic material, the piezoelectric constant d33 is greater than 500pC / N, and the piezoelectric anisotropy d33 / d31 is greater than 3.5.

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 belongs to the technical field of piezoelectric ceramics, and discloses a lead-free piezoelectric ceramic and a preparation method thereof. The general formula of the lead-free piezoelectric ceramic is 0.95 (K < 0.48 > Na < 0.52 >) NbO < 3-0.05 > (Bi < 0.5 > Na < 0.5 >) HfO < 3-0.002 > Fe < 2 > O < 3-x > CuO, wherein x is greater than or equal to 0.005 and less than or equal to 0.015. On the basis of constructing an orthogonal-tetragonal phase boundary (O-T phase boundary), CuO is introduced for doping, and by controlling the doping amount, not only can a defect dipole be introduced, but also multi-phase coexistence can be maintained, and a nano-scale domain can be increased. Multi-phase coexistence and a nano-scale domain ensure a relatively low polarization potential barrier, so that a high-voltage coefficient is maintained; the defect dipole can effectively inhibit domain wall movement and reduce loss; and the mechanical quality factor is obviously improved while the piezoelectric coefficient is kept at a relatively high level.

The invention discloses an MEMS loudspeaker, a manufacturing method thereof and an electronic device, and the method comprises the steps: providing a semiconductor substrate which comprises a first surface and a second surface which are opposite to each other, and sequentially forming a vibrating diaphragm layer, an insulating layer and a first electrode layer on the first surface of the semiconductor substrate; forming a lithium niobate piezoelectric layer on the first electrode layer; forming a second electrode layer on the lithium niobate piezoelectric layer; patterning the lithium niobate piezoelectric layer, the first electrode layer, the insulating layer and the diaphragm layer to form a vibration structure and a fixed end which are separated by a groove; a flexible covering layer covering the bottom and the side wall of the groove is formed, and the vibration structure is connected with the fixed end through the flexible covering layer; and etching the semiconductor substrate from the second surface of the semiconductor substrate to form a cavity. The sound pressure level of the MEMS loudspeaker can be improved by adopting lithium niobate as the piezoelectric layer, and the amplitude of the vibration structure can be improved by adopting the flexible covering layer to connect the vibration structure and the fixed end.

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 relates to the technical field of sensors, in particular to a Te nanotube-based thermoelectric-piezoelectric single-channel two-parameter sensor and a manufacturing method thereof. The sensor comprises a multi-layer composite film structure which sequentially comprises a polyimide flexible substrate, a lower electrode indium tin oxide conductive layer, a SiO2 dielectric layer, a Te nanotube film sensing layer, a polydimethylsiloxane packaging protection layer and an upper electrode gold layer from bottom to top, and gold wires are led out from the upper electrode gold layer and the lower electrode indium tin oxide conductive layer through elargol to serve as unique output ends; the polyimide flexible substrate serves as a flexible support, and the upper electrode gold layer, the lower electrode indium tin oxide conductive layer and an external circuit form a loop to output signals. The thermoelectric-piezoelectric single-channel two-parameter sensor can simultaneously output thermoelectric-piezoelectric signals in a single channel, has excellent flexibility, is simple in preparation method and low in cost, can realize large-scale preparation and miniaturized application, and has great potential in the fields of medical health, human-computer interaction and the like.

The invention discloses a lead-free piezoelectric ceramic material and a preparation method thereof, the chemical general formula of the lead-free piezoelectric ceramic material is (0.96-x) K < 0.48 > Na < 0.52 > Nb < 0.98 > Sb < 0.02-0.04 > Bi < 0.5 > Na < 0.5 > ZrO < 3-x > Bi < 0.5 > Ag < 0.5 > ZrO < 3 >, x is greater than or equal to 0.005 and less than or equal to 0.03, and y is greater than or equal to 0.05 and less than or equal to 0.03. The content of the Ag element in the ceramic material is 0.15-0.87 wt%; according to the ceramic material, a compound Bi0. 5Ag0. 5ZrO3 is introduced on the basis of KNNS-BNZ-based ceramic to regulate and control a piezoelectric ceramic structure, so that phase transformation temperatures TR-O and TO-T are transferred to room temperature, and a three-phase coexistence phase boundary of a nanoscale trigonal phase (R)-orthorhombic phase (O)-tetragonal phase (T) is constructed in a room temperature region.

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.

The present invention provides a self-assembled omnidirectional high-temperature vibration sensor array based on two-dimensional crystal piezoelectric materials, belonging to the field of vibration sensor technology, wherein each unit includes a single crystal silicon substrate; a stress layer formed on the single crystal silicon substrate; a heterojunction formed on the stress layer, the heterojunction including a gate electrode, a dielectric layer, a two-dimensional crystal piezoelectric material layer, a source electrode, a drain electrode and a nano protective layer arranged in sequence; driven by the stress layer, the heterojunction is self-assembled into a curled semicircular three-dimensional structure. A multi-layer (≥3) circular array is performed on the above structure to obtain a three-dimensional self-assembled omnidirectional piezoelectric vibration sensor array structure. The present invention also discloses a method for making a self-assembled omnidirectional high-temperature vibration sensor array based on two-dimensional crystal piezoelectric materials. The miniaturization of the omnidirectional vibration sensor is achieved through monolithic integration, and high sensitivity, wide range and high temperature resistance detection are also achieved.

This invention relates to the field of piezoelectric ceramic materials technology, and provides a sodium bismuth titanate ceramic material with a non-stoichiometric composition at the A-site, its preparation method, and its applications. The chemical formula of the sodium bismuth titanate ceramic material is Na. 0.5‑y Bi 0.5‑x TiO3, wherein 0≤x≤0.4, 0≤y≤0.4. This invention, through compositional design and control, prepares sodium bismuth titanate piezoelectric ceramics with non-chemically composed A-sites via solid-state sintering. Different A-site defects respectively improve the coercivity and piezoelectric coefficient of the sodium bismuth titanate piezoelectric ceramics. The matrix Na... 0.5 Bi 0.5 The coercive field of TiO3 ceramics is 70 kV / cm, and the piezoelectric coefficient d is... 33 A piezoelectric ceramic sample with a coercive field of 81 kV / cm at x = 0.03 and y = 0 can achieve a piezoelectric coefficient d of 95 pC / N. 33 .

The invention discloses a piezoelectric ceramic substrate and a preparation method thereof, the piezoelectric ceramic substrate comprises a potassium sodium niobate-bismuth sodium zirconate piezoelectric ceramic material component and a barium titanate microcrystalline glass material component, and the molar ratio of the element Nb to the element Ba in the piezoelectric ceramic substrate is (97-99.9): (0.01-3). The preparation method comprises the following steps: proportionally weighing prepared potassium sodium niobate-sodium bismuth zirconate piezoelectric ceramic powder and barium titanate glass ceramic powder, wherein the potassium sodium niobate-sodium bismuth zirconate piezoelectric ceramic powder accounts for 95.0-99.5 wt%, and the barium titanate glass ceramic powder accounts for 0.5-5 wt%; and the mixed powder is sequentially subjected to rolling ball milling, granulation, compression molding, glue discharging and sintering, and then the piezoelectric ceramic substrate with the molar ratio of the element Nb to the element Ba being (97-99.9): (0.01-3) is prepared, wherein the molar ratio of the element Nb to the element Ba is equal to (97-99.9): (0.01-3).

The invention relates to the technical field of space dust measurement, in particular to a flexible film sensor, which comprises a packaging layer, a fixed substrate, an electrode layer and a sensing unit, and is characterized in that the sensing unit is a PVDF (Polyvinylidene Fluoride) film; the electrode layer comprises an upper electrode layer and a lower electrode layer, and each of the upper electrode layer and the lower electrode layer is of a multi-layer stacked structure prepared through a magnetron sputtering process by taking a PVDF film as a substrate; the fixed substrate comprises an upper fixed substrate and a lower fixed substrate, the upper fixed substrate is fixedly assembled with the upper electrode layer, and the lower fixed substrate is fixedly assembled with the lower electrode layer; the packaging layer comprises an upper packaging layer and a lower packaging layer, the upper packaging layer is fixedly connected with the upper fixing substrate through bolts, and the lower packaging layer is fixedly connected with the lower fixing substrate through bolts. The sensor is used for dust momentum characteristic measurement, the sensitivity of the sensor is improved by performing Au / Cr metal magnetron sputtering on the PVDF film, and meanwhile, the response layer is the polarized PVDF film and has a high piezoelectric coefficient.

The invention discloses a cantilever beam structure containing a piezoelectric single crystal film, a laser modification auxiliary preparation method of the cantilever beam structure and an MEMS device, and belongs to the technical field of MEMS. Laser modification and a wet etching process are combined to accurately and quickly etch a single crystal lithium niobate or lithium tantalate substrate sheet to obtain a cantilever beam structure containing a piezoelectric single crystal film, a cavity is formed in an internal area of the substrate sheet, the piezoelectric single crystal film is arranged on the surface layer of one surface of the substrate sheet relatively close to the cavity and covers the cavity, and the piezoelectric single crystal film is arranged on the surface layer of the other surface of the substrate sheet. At least one micropore is formed in the position, opposite to the edge of the cavity, of the edge of the piezoelectric single crystal film, and the cavity is communicated with the outside of the base piece through the micropore. According to the invention, the single crystal lithium niobate or lithium tantalate film and the cantilever beam structure are prepared at the same time and are used in the MEMS device, and the same material structure design of the cavity layer and the piezoelectric single crystal film layer can effectively solve the problems of stress matching and compensation of the cavity layer and the piezoelectric single crystal film layer; and the problem that the performance of the device is reduced due to internal lattice mismatch caused by a traditional piezoelectric single crystal film deposition method is solved.

The present application relates to the technical field of lithium metal battery, and especially relates to a negative electrode interface protection layer and a preparation method, a lithium metal negative electrode and a lithium metal battery. The preparation method comprises the following steps: under stirring, adding bismuth ferrite into a PVDF-HFP solution in batches, ultrasonic dispersion and mixing, obtaining a precursor solution, dropping the precursor solution on a copper foil, adopting a two-stage spin coating process to form a wet film, drying, obtaining a copper foil loaded with a composite protection layer BFO / PVDF-HFP, and carrying out high-voltage corona polarization treatment on the copper foil loaded with the composite protection layer BFO / PVDF-HFP, thereby obtaining the negative electrode interface protection layer. The negative electrode interface protection layer is more sensitive to the stress response of the lithium metal negative electrode volume strain and lithium dendrite, and generates a stronger piezoelectric field more quickly. Under the action of the electric field, the lithium ion flux is larger and more uniform, the lithium deposition is more uniform and dense, the growth of lithium dendrites is effectively inhibited, and the lithium metal is protected while the lithium deposition / peeling behavior is more effectively regulated.

The invention provides bismuth ferrite-barium titanate piezoelectric ceramic with a heterostructure and a preparation method of the bismuth ferrite-barium titanate piezoelectric ceramic. The ceramic is formed by sequentially laminating and pressing a layer A, a layer B and a layer B, the structural general formula of the layer A is BaTi (1-x) SnxO3; the general structural formula of the layer B is as follows: 0.75 BiFeO3 <-0.25 > BaTiO3 <-y >% MnO2; 0 < x < = 0.16, and 0 < y < = 1. The preparation method comprises the following steps: sequentially laminating and pressing the A-layer raw material and the B-layer raw material into a sheet according to A, B and A to obtain a plain sheet, and then carrying out glue removal, electroplating and polarization on the plain sheet. The piezoelectric ceramic disclosed by the invention has piezoelectric property and thermal stability at the same time.

The invention discloses a piezoelectric polymer and a blood pressure monitoring device based on the piezoelectric polymer, and relates to the technical field of blood pressure monitoring, the piezoelectric polymer comprises polyvinylidene fluoride, polyvinyl alcohol and N, N-dimethylacetamide according to the weight ratio of (61-71): (19-22): (400-500); the blood pressure monitoring device comprises a pressure sensor and a signal processing system, and the pressure sensor is in communication connection with the signal processing system; a sensitive material in the pressure sensor is a piezoelectric polymer; the piezoelectric polymer has higher piezoelectric property and has higher sensitivity to the real-time change state of the blood pressure in the blood pressure monitoring process, the detection result can be more accurate, and the device is suitable for being used in the treatment process of critical patients.

The invention discloses a preparation method of a full-flexible PZT film, which comprises the following steps: (1) uniformly depositing an LSMO coating on a fluorophlogopite substrate, and crystallizing the LSMO coating; (2) spin-coating a plurality of PZT thin film layers on the crystallized LSMO coating to obtain a PZT / LSMO / mica product; (3) preparing a flexible supporting layer on the PZT thin film layer; and (4) immersing the product in an etching solution to completely dissolve the LSMO coating so as to obtain the full-flexible PZT film. The invention also discloses a preparation method of the full-flexible PZT sensor. The preparation method comprises the following steps: S1, designing the interdigital electrode and printing the interdigital electrode on the PET substrate; and S2, transferring the full-flexible PZT thin film to a PET substrate, and then performing packaging and polarization to obtain the full-flexible PZT sensor. The full-flexible PZT sensor with the characteristics of high performance and ultrasensitivity is obtained on the flexible PET substrate through a transfer strategy with high cost performance, so that not only is the excellent electrical property of the perovskite structure film improved, but also higher mechanical flexibility is shown.

The invention relates to preparation of a samarium and cobalt co-doped bismuth ferrite nano material and application of the samarium and cobalt co-doped bismuth ferrite nano material in the field of piezoelectric light concerted catalysis. Compared with pure-phase BiFeO3, the samarium and cobalt co-doped bismuth ferrite nano material synthesized by a coprecipitation method shows a remarkably enhanced piezoelectric optical effect. Under the synergistic effect of ultrasound and light, the samarium and cobalt co-doped bismuth ferrite nano material can achieve efficient degradation of rhodamine B and remarkable improvement of hydrogen production efficiency, the degradation rate constant is 14.36 times that of pure-phase BiFeO3, and the hydrogen production efficiency is 1.73 times that of pure-phase bismuth ferrite. By doping the samarium element, the piezoelectric coefficient of bismuth ferrite is improved, and the efficiency of piezoelectric light concerted catalytic reaction is further improved. The cobalt element is doped into the bismuth ferrite, so that the photocatalytic activity of the bismuth ferrite is improved, and the piezoelectric light synergistic catalytic performance of the material is effectively improved. The invention provides a method for improving rhodamine B degradation and water decomposition of the material to generate hydrogen through element doping, and the method has the characteristics of simple process flow and strong operability, and has wide application prospects.

This invention provides a 1D / 2D dual piezoelectric photocatalytic composite material, its preparation method, and its application, relating to the field of wastewater treatment technology. The 1D / 2D dual piezoelectric photocatalytic composite material of this invention comprises a heterojunction structure consisting of one-dimensional rod-shaped barium titanate and a two-dimensional bismuth-rich halide oxide; the one-dimensional rod-shaped barium titanate is rod-shaped BaTiO3 grown along the c-axis orientation; the two-dimensional bismuth-rich halide oxide is Bi... x O y X z X is at least one of Cl, Br, or I; the BaTiO3 and Bi x O y X z The molar ratio is (1-10):(1-10); the lattice matching degree of the heterojunction is >90%. This invention constructs a 1D / 2D dual piezoelectric heterojunction structure with high lattice matching degree, combined with a curing method involving chemical bonding of a hydroxylated modified layer and a silane coupling agent, and uses an aeration-driven approach to achieve synergistic enhancement of piezoelectric effect and photocatalytic performance. This significantly improves carrier separation efficiency and catalyst stability, reduces energy consumption, and provides a new direction for the efficient treatment of organic wastewater, showing promising application prospects.

The invention relates to a piezoelectric copolymer film preparation method for an MEMS hydrophone, and the method comprises the following steps: 1, carrying out the surface oxidation treatment of a substrate, selecting a monocrystalline silicon wafer as the substrate, carrying out the ultrasonic cleaning of the substrate for more than 10 min through acetone, absolute ethyl alcohol and ultrapure water in sequence, and then drying the substrate, a 250-250nm insulating silicon dioxide layer is prepared on a monocrystalline silicon substrate by adopting a wet oxygen oxidation treatment method, and the insulating silicon dioxide layer is used for ensuring the insulation between the piezoelectric MEMS device and the monocrystalline silicon substrate and improving the binding force among the lower electrode layer, the piezoelectric copolymer film layer and the substrate. According to the invention, the preparation of the film of 5-10 microns can be realized.

The present invention provides a solid electrolyte. The solid electrolyte may include a compound in which a cation and an anion are combined, wherein the cation includes thiophenium, and the anion includes fluorine.

This invention discloses a core-shell composite piezoelectric fiber material and its preparation method. The invention first prepares a core-shell composite nanofiber with PVDF-TrFE as the shell and PC as the core using a coaxial spinning process. Using PC as the core increases the elastic modulus of the composite piezoelectric fiber, resulting in a larger piezoelectric potential than pure PVDF-TrFE fibers under the same strain. Simultaneously, PC forms hydrogen bonds at the interface with PVDF-TrFE, increasing the crystallinity of the PVDF-TrFE shell and thus improving the piezoelectric properties. The core-shell composite piezoelectric fiber has a d... 33 The piezoelectric coefficient can reach 49.1 pC N. ‑1 It is 110% higher than that of pure PVDF-TrFE.

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 invention discloses a piezoelectric ceramic for a piezoelectric ceramic fan and a preparation method thereof, the chemical formula of the ceramic material is m% Me2O3-(1-x-y-z) Pb (Mg1 / 3Nb2 / 3) O3-xPb (Zn1 / 2Nb2 / 3) O3-yPbTiO3-zPbZrO3, Me is any one or two of Pr, Ho, Eu, Dy, Nd, Yb, La, Sm, Y, Er and Lu, m% refers to the molar percentage of Me2O3 in (1-x-y-z) Pb (Mg1 / 3Nb2 / 3) O3-xPb (Zn1 / 2Nb2 / 3) O3-yPbTiO3-zPbZrO3, 0.05 < = x < = 0.8, 0.05 < = y < During preparation, step-by-step synthesis and two-step sintering are adopted, the component gradient and proportion can be regulated and controlled, obtained ceramic grains are fine and uniform and high in density, Me2O3 rare earth element is doped into a multiphase piezoelectric ceramic matrix, good temperature stability and high piezoelectric coefficient are obtained within the range of-60 DEG C to 120 DEG C, and d33 is not lower than 1695 pC / N. The piezoelectric ceramic fan has important application in the field of piezoelectric ceramic fans, and is expected to be widely applied in the fields of precise positioning systems, medical imaging equipment, sensors and actuators, energy collection and conversion, consumer electronics, unmanned aerial vehicles and micro aircrafts.