11 results about "Spontaneous polarization" patented technology

The application discloses a screening method and device of piezoelectric anisotropic perovskite material, and high-throughput calculation and screening are performed on tetragonal phase ABO3 perovskite oxide material through first principle calculation, the correlation between piezoelectricity and lattice tetragonality, polarization displacement, spontaneous polarization and elastic constant is pointed out, and the method can be used for screening and guiding design of high-performance piezoelectric material. The application gives a three-dimensional representation of piezoelectric coefficient, re-evaluates the piezoelectric coefficient ratio |d 33 / d 31 | which is widely used at present, and points out the deficiency in representing piezoelectric anisotropy, and can be extended to anisotropy of other piezoelectric materials.

This invention discloses a method for establishing a phase-field model of a polycrystalline phase relaxor ferroelectric, the method comprising the following steps: 1. Determining the free energy of the polycrystalline phase relaxor ferroelectric; 2. Determining the order parameter of the polycrystalline phase relaxor ferroelectric as spontaneous polarization. P i 3. Represent free energy as spontaneous polarization P i The invention employs several methods: 1) introducing ferroelectric-ferroelectric phase boundaries and random local electric fields; 2) solving the Ginzburg-Landau partial differential equations to obtain the spatial evolution of spontaneous polarization, thereby determining the domain structure of polycrystalline relaxed ferroelectrics and ultimately establishing a phase-field model for polycrystalline relaxed ferroelectrics. Based on a model ferroelectric system, this invention, by considering ferroelectric-ferroelectric phase boundaries and random local electric fields, reproduces the unique domain structure characteristics of polycrystalline relaxed ferroelectrics with the coexistence of multiple nanometer-sized ferroelectric phases, establishes a phase-field model for polycrystalline relaxed ferroelectrics, and improves the theoretical model of polycrystalline relaxed ferroelectrics, which is beneficial for guiding the design of novel high-performance ferroelectric materials.

The present application relates to a kind of barrier layer structures with asymmetric insertion layer, including barrier layer, barrier layer is used to form source, gate and drain, insertion layer is embedded in barrier layer inside, insertion layer forms first insertion section between source to gate, forms second insertion section between gate to drain, the thickness of first insertion section is less than the thickness of second insertion section;A kind of power device, including barrier layer structure with asymmetric insertion layer.In the present application, the spontaneous polarization, piezoelectric polarization effect of asymmetric insertion layer is much stronger than barrier layer, the insertion layer of gate, drain side is thicker, resulting in local barrier being higher, electric field peak spontaneously migrates from gate edge to drain side and gradually reduces, the distribution of peak electric field is optimized, and the overall performance of device is improved;The breakdown voltage of the present application is effectively improved, peak electric field is significantly reduced, Ron is not degraded basically, current collapse effect is significantly inhibited, meet the design requirements of high-voltage GaN HEMT.

The application discloses a kind of multilayer co-extrusion forming process of anti-static ton barrel, belong to anti-static ton barrel technical field, comprising: by inside to outside sequentially by high clean induction layer, gradient dielectric adhesive layer, high barrier layer, adhesive layer, structural support layer and composite conductive outer layer of multilayer parison formed by multilayer co-extrusion;Blow molding and cooling setting;Ring copper alloy bus ring is embedded in barrel body bottom and installs elastic ground contact, and ground is led out by shielding wire.This application adds ternary hybrid conductive component in high clean induction layer and constructs quasi-continuous charge bridge, so that internal static charge is led out across interface;Gradient dielectric adhesive layer forms dielectric constant gradient and spontaneous polarization electric field, reduces charge migration energy barrier;Combination gradient cooling solidification filler orientation and inhibit thermal stress.This application realizes the efficient discharge of internal static electricity of ultrahigh resistivity liquid under the premise of maintaining the ultrahigh cleanliness of inner layer, simultaneously has excellent interlaminar bond strength and long-term environmental adaptability.

This invention discloses a ferroelectric liquid crystal composition comprising a first component, a second component, and a third component. The first component comprises one or more compounds of general formula I, the second component comprises one or more compounds of general formula II, and the third component comprises one or more compounds of general formula III. The ferroelectric liquid crystal composition has the advantages of high transmittance, high contrast, large phase transition range, small pitch, and high spontaneous polarization intensity. This invention also provides a display device comprising the ferroelectric liquid crystal composition.

The application discloses a ferroelectric liquid crystal composition, which comprises a first component and a second component, wherein the first component comprises one or more compounds of general formula I, and the second component comprises one or more compounds of general formula II. The ferroelectric liquid crystal composition has the advantages of high transmittance, large contrast, large phase transition range, small pitch and high spontaneous polarization intensity. The application further provides a display device comprising the ferroelectric liquid crystal composition.

This invention discloses a method and system for using ferroelectric lead titanate materials in lithium-mediated ammonia synthesis. The method involves growing an n-type semiconductor buffer layer on the surface of a porous current collector, assembling ferroelectric nanocrystals via electrophoretic deposition and annealing to form an oriented ferroelectric nanoarray layer, and constructing a multi-level heterojunction composite electrode with physical gaps. After high-voltage polarization to align the spontaneous polarization vectors perpendicularly, a nitrogen reduction reaction is driven in an organic electrolyte. This invention utilizes the interfacial Schottky barrier to block the hydrogen evolution side reaction and opens electron channels through the positive piezoelectric effect excited by lithium deposition stress; it utilizes the flexural electric effect induced by deposition morphology to drive proton directional transport along domain walls, and uses the mechanical compressive stress generated by the inverse piezoelectric effect to suppress lithium dendrite growth. This method achieves multi-field coupling control of force, electricity, and chemistry, significantly improving the Faraday efficiency and electrode stability of ammonia synthesis.

This invention discloses a natural gas energy-saving system and treatment method employing the synergistic effect of tourmaline ceramic particles and magnetization. The system includes a multi-stage precision filter, a tourmaline-based supported catalyst filled inside a magnetic-catalytic coupling reactor, and the spontaneous polarization characteristics of the tourmaline support synergistically activate natural gas molecules. An array of permanent magnets arranged in a Halebeck structure or a multi-pole opposing focusing structure is installed outside or inside the reactor to form a high-intensity gradient magnetic field in the catalyst bed. An intelligent control module is also included to monitor the natural gas composition and dynamically adjust the magnetic field strength. This invention, through deep coupling of the magnetic field and tourmaline catalysis, reduces the reaction activation energy and operating temperature, extends the catalyst life, and adapts to gas quality fluctuations by intelligently adjusting the magnetic field strength, thus solving the problems of easy deactivation of single catalysts and unstable single magnetization effects, effectively improving the stability of natural gas treatment.

This invention provides Na 0.5 Bi 0.5 The application of TiO3 materials in the catalytic degradation of organic pollutants; this invention discovers that Na… 0.5 Bi 0.5 TiO3 materials possess pyroelectric properties and exhibit spontaneous polarization dependent on temperature oscillations. This allows them to generate polarized charge carriers, thereby catalyzing the degradation of organic pollutants through pyroelectricity. The thermal energy generated by temperature fluctuations is efficiently converted into chemical energy, enabling the degradation of pollutants under conditions of temperature variation in darkness, natural nighttime temperature differences, and natural daytime temperature differences under illumination.

The application discloses a ferroelectric material modified perovskite solar cell and a preparation method thereof. The ferroelectric material modified perovskite solar cell is composed of a transparent conductive substrate, an electron transport layer, a perovskite active layer and a carbon electrode which are sequentially stacked. The active layer is prepared from a perovskite material doped with a ferroelectric material (C6H5CH2NH3)2CsPb2Br7. The doping concentration of the ferroelectric material is 0.01-0.05 mol%. The spontaneous polarization characteristics of (C6H5CH2NH3)2CsPb2Br are used to enhance the built-in electric field in the device, inhibit non-radiative recombination, significantly improve the photoelectric conversion efficiency and stability of the cell, and the process is simple and the cost is controllable. The technical bottleneck of poor stability, weak built-in electric field and poor material adaptability of the existing carbon-based perovskite solar cell is solved, and the application can be widely used in the fields of photovoltaic power generation, portable electronic device power supply and building photovoltaic integration.

This invention discloses a ferroelectric liquid crystal composition comprising a first component and a second component. The first component contains one or more compounds of general formula I, and the second component contains one or more compounds of general formula II. The ferroelectric liquid crystal composition has the advantages of high transmittance, high contrast, large phase transition range, small pitch, and high spontaneous polarization intensity. This invention also provides a display device comprising the ferroelectric liquid crystal composition.