7results about How to "Improve piezoelectric performance" patented technology

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.

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.

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.

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.