64 results about "Calcium copper titanate" patented technology

The invention relates to a method for preparing high dielectric, low-loss and insulating calcium copper titanate ceramics, belonging to the technical field of high dielectric ceramic materials. The calcium copper titanate ceramics are prepared from initial raw materials of CaCO3 or CaO, CuO and TiO2, wherein after being mixed, the raw materials are processed by mix grinding and then processed by presintering at the temperature from 800 DEG C to 950 DEG C after mix grinding, hard blocks after presintering are cracked to be ground, and the powdered materials after presintering and grinding are prepared into green bodies with predetermined shapes; and the green bodies are heated to the sintering temperature ranging from 960 DEG C to 990 DEG C from room temperature, and heat preservation is carried out for 1 to 24 hours at the sintering temperature, thereby realizing the sintering densification of the ceramics. The preparation method controls performance parameters by controlling technological parameters, and structural changes and chemical reactions in a sintering process. The ceramic materials prepared by the method can meet the requirement on industrial application; and simultaneously, compared with the prior art, the preparation method can obviously reduce the energy consumption, is environment-friendly and reduces the production cost.

Complex metal oxide-containing pellets and their use for producing hydrogen. The complex metal oxide-containing pellets are suitable for use in a fixed bed reactor due to sufficient crush strength. The complex metal oxide-containing pellets comprise one or more complex metal oxides and at least one of in-situ formed calcium titanate and calcium aluminate. calcium titanate and calcium aluminate are formed by reaction of suitable precursors in a mixture with one or more complex metal carbonates. The complex metal oxide-containing pellets optionally comprise at least one precious metal.

The present invention belongs to the field of composite materials, and relates to a high dielectric constant ceramic/polymer matrix composite dielectric material and a preparation method thereof. The high dielectric constant ceramic/polymer matrix composite dielectric material is formed by carrying out hot pressing on polyvinylidene fluoride and calcium copper titanate ceramic mixed powder. The preparation method comprises the following steps: preparing materials, carrying out mixing grinding, and carrying out hot pressing molding. The ceramic/polymer matrix composite dielectric material has the following characteristics that: a dielectric constant is high, a filling amount of a filler is easily controlled, and engineering practicability is provided.

The invention discloses a method for preparing a composite inorganic metal oxide, which comprises the following steps: firstly, preparing a precursor of the composite inorganic metal oxide; and then, treating the precursor by a calcining or burning method, wherein the precursor is a homogeneous liquid substance formed by mixing liquid polylol and more than two metal organic salts, and the contentratio of all metal elements in the precursor accords with the requirement of forming the composite inorganic metal oxide. The method can prepare powder of various composite inorganic metal oxides of nano-scale crystal grains, which comprise barium titanate, calcium copper titanate, lithium titanate, strontium titanate, barium zirconate or strontium zirconate and the like.

The invention provides a preparation method of a polymer-based dielectric composite material of a silica-coated calcium copper titanate nanofiber. The method comprises the following steps: preparing acalcium copper titanate nanofiber through an electrospinning technology, uniformly coating the calcium copper titanate nanofiber with a layer of silica by using the hydrolysis characteristic of tetraethyl orthosilicate in an alkaline solution, and uniformly dispersing the obtained filler in a polymer matrix through a solution dispersion technology or a melt blending technology to produce a composite film. The inorganic ceramic filler is coated with the silica insulating layer in the preparation method, so the dielectric loss of the composite material is reduced and the breakdown strength is improved while preserving the high dielectric properties. The composite material can be applied to high-energy density dielectric capacitors as a dielectric layer due to its excellent dielectric properties.

The invention discloses a cyanate resin base composite material with a low percolation threshold and a high dielectric constant and a preparation method thereof. The cyanate resin base composite material is characterized by comprising the following components by volume: 10%-15% of calcium copper titanate, 0.5%-3.0% of expanded graphite sheets and 89.5%-82.0% of cyanate, wherein the granularity of the calcium copper titanate ranges from 1 micrometer to 2 micrometers; the diameters of the expanded graphite sheets are 10-50 micrometers, and radius-thickness ratio is between 300 and 500. The preparation method of the cyanate resin base composite material comprises the following steps of: mixing the calcium copper titanate, the expanded graphite sheets and the cyanate; and melting at 80-100 DEG C, then raising temperature to 120-150 DEG C, and pre-polymerizing until obvious sedimentation of the calcium copper titanate and the expanded graphite sheets exists. The invention can obviously enhance the dielectric constant of the cyanate resin base composite material by regulating the relative content of added components in the cyanate resin base composite material and utilizing synergistic effect generated among physically and chemically treated components, has the advantages of great low percolation threshold, low dielectric loss, good heat resistance, low cost, simple preparation method, and the like and has wide application prospect in the fields of electronic engineering, electrical engineering, and the like as a composite material with the high dielectric constant.

The invention discloses a fluorine-containing polymer-based dielectric composite film. The dielectric composite film is prepared from conductive metal powder, calcium copper titanate, rubber particles and fluorine-containing polymer as raw materials in the presence of a compound liquid of N, N-dimethyl acetamide and polyacrylic acid as a solvent, wherein the mass ratio of components is (0-2.5): (10-30): (0-3): 10. The invention also discloses a preparation method of the composite film. The fluorine-containing polymer-based dielectric composite film is a dielectric composite film which has the advantages of high dielectric constant, high compressive strength, low dielectric loss and excellent elongation and controllable thickness.

The invention provides a capacitive pressure touch sensor. The capacitive pressure touch sensor comprises an upper electrode, a lower electrode and a binder bonded to the upper electrode and the lowerelectrode. The binder comprises a transparent resin adhesive and nanometer calcium copper titanate according to a mass ratio of 100: 0.1-20. The invention also provides an electronic component and anadhesive. Through use of a certain amount of CCTO with a certain particle size in the transparent resin adhesive, the adhesive is obtained. The adhesive can significantly improve touch sensitivity ofthe capacitive pressure touch sensor and basically does not influence the light transmittance.

The invention relates to the technical field of dielectric ceramic materials, and in particular relates to a preparation method for copper calcium titanate. The method comprises the following steps: (a) mixing a calcium source, a copper source and a titanium source, and performing grinding treatment to obtain a mixed material; and (b) performing laser excitation on the mixed material obtained in the step (a) under laser irradiation, and performing self-propagating sintering until the mixed material forms a black crystal, so as to obtain the calcium copper titanate, wherein the calcium source,the copper source and the titanium source are mixed according to a molar ratio of calcium to copper to titanium of 1:(2.8-3.5):(3.5-4.6). The preparation method provided by the invention has the advantages of a simple operation process, convenient control, high production efficiency, low production costs, and no added coupling agent, spinning aid, binder, solvent and the like in the synthetic process, and the costs are lower than those of a current method for preparing copper calcium titanate by high-temperature sintering.

The invention discloses a giant dielectric composite ceramic copper calcium titanate material and a preparation method and application thereof and belongs to the technical field of electronic ceramicmaterial preparation. According to the method, micro powder and nano powder which are synthesized by a solid-phase method and a sol-gel method are mixed for preparing the composite ceramic copper calcium titanate material, and the preparation process is simple, controllable and high in repeatability and yield. Moreover, by changing the composite ratio of the micro and nano powder, the crystal grain size and range of the composite ceramic copper calcium titanate material can be regulated and controlled, and therefore, the compact composite ceramic copper calcium titanate material with a high dielectric constant (5*104), low loss (0.051), high breakdown field strength (2,374V/cm) and high energy storage density (20kJ/m<3>) is obtained, wherein the energy storage density of the composite ceramic material is 12.7 times higher than that of ceramics prepared from micro powder and 12.1 times higher than that of ceramics prepared from nano powder. The composite ceramic copper calcium titanatematerial prepared by the method has high practicability, can be used as a dielectric material for preparing high-dielectric multilayer ceramic capacitors and dynamic random access memories, and can also serve as a pressure-sensitive ceramic material in the fields of electric power, electronic systems and the like.

The invention relates to a method for preparing dielectric ceramic materials and in particular relates to a method for preparing a copper titanate calcium-based ceramic with a core-shell structure. The method for preparing the copper titanate calcium-based ceramic with the core-shell structure comprises the following steps: (1) taking calcium nitrate, copper nitrate and tetrabutyl titanate as initial raw materials, adding citric acid, and preparing CCTO powder by utilizing a sol-gel method; (2) accurately weighing the CCTO powder, magnesium nitrate and tetrabutyl titanate according to a stoichiometric ratio of CCTO/xMgTiO3, weighing the citric acid, fully stirring the materials in ethanol, forming suspension, and finally obtaining CCTO/MgTiO3 mixed powder; and (3) fully grinding the powder, pressing into sheets under the pressure of 150 MPa, sintering at the temperature of 1080 DEG C for 10 hours, thereby obtaining the CCTO/xMgTiO3 ceramic.

The invention discloses a method for preparing a porous copper calcium titanate CaCu3Ti4O12 (abbreviated as CCTO) thin film. The method uses lanthanum nickelate LaNiO3 (abbreviated as LNO) as a buffer layer, and adopts a solution chemical method to coat on a substrate covered with LNO. CCTO wet film; through heat treatment, a CCTO film with a porous structure is obtained. The invention does not need a template, and can prepare a CCTO film material with a porous structure on the surface under low-cost process conditions, and has broad application prospects in the fields of porous ceramics, high-density energy storage, and the like.

The invention provides a manganese-zinc power ferrite material and a preparation method thereof. The ferrite material comprises the following main components: 73-74 wt% of ferric oxide, 3-4 wt% of zinc oxide and the balance of manganese oxide, and comprises the following auxiliary components: 500-1000 ppm of calcium carbonate, 200-500 ppm of silicon dioxide, 2000-5000 ppm of cobaltosic oxide, 100-200 ppm of zirconium oxide, 200-600 ppm of niobium pentoxide, 100-200 ppm of zirconium oxide, 200-1000 ppm of titanium dioxide and 1000-2000 ppm of copper calcium titanate. The high-frequency loss of the manganese-zinc power ferrite material is reduced through trace additives such as copper calcium titanate, the power loss of the manganese-zinc ferrite material is greatly reduced while the magnetic conductivity and saturation flux density performance are kept not deteriorated, and the manganese-zinc power ferrite material has high saturation flux density.

The invention belongs to the field of direct-current cable accessory materials, and particularly relates to a silicon rubber-based non-linear cable accessory material and a preparation method thereof.The preparation method comprises the following steps: firstly, preparing copper calcium titanate particles in certain particle size through a sol-gel method and by carrying out high-temperature calcination and ball milling; secondly, dispersing the copper calcium titanate particles in double-component liquid silicon rubber through in-situ polymerization; finally, carrying out hot-pressing and vulcanization forming, thus preparing the silicon rubber-based non-linear cable accessory material. The silicon rubber-based non-linear cable accessory material prepared by the invention has excellent conductance nonlinearity and relatively stable direct-current breakdown electric field strength and is capable of effectively improving conductance gradient between different materials, increasing the transportation capability of a current carrier and weakening an accumulative effect of space charges in the position of an interface, so that removing of local electric field distortion can be realized, electric field distribution in a cable accessory can be homogenized, the accessory insulation performance can be enhanced, the failure occurrence probability can be reduced, and the service life ofthe cable accessory can be prolonged. The preparation method and needed equipment are simple, the cost is low, and implementation is easy.

The invention discloses a sintering method for preparing copper calcium titanate CaCu3Ti4O12 (CCTO) ceramic with low dielectric loss and high dielectric constant based on reducing-oxidizing atmospheresynergistic sintering. The invention belongs to the field of ceramic sintering. The following technical schemes are adopted: a CCTO ceramic green body is put into an atmosphere sintering furnace; theceramic green body is subjected to a heating stage I under the air atmosphere, a heat preservation stage I under the air atmosphere, a heating stage II under the air atmosphere, a heat preservation stage II under the atmosphere of introducing reducing mixed gas, a cooling stage I under the condition of introducing non-reducing gas without oxygen, a rapid cooling stage II under the condition of introducing oxygen-rich mixed gas, and a furnace cooling stage III in the atmosphere furnace to obtain the CCTO ceramic sintered body. The dielectric property of the CCTO ceramic obtained through the sintering method in the technical scheme is obviously improved, the dielectric constant reaches up to 5 *10 <4 > at the frequency of 1 kHz, and meanwhile the dielectric loss is lower than 0.02.

The invention provides a preparation method of a high-dielectric-property copper calcium titanate epitaxial film, which comprises the following steps of firstly, preparing calcium, copper and titanium solutions by using a sol-gel method, and then synthesizing copper calcium titanate sol, secondly, cleaning an SrTiO3 (001) substrate, and preparing a copper calcium titanate gel film on the substrate by using a dip-coating method, and finally, carrying out heat treatment under different atmospheres and temperatures to obtain the single-orientation CCTO film. The single-orientation copper calcium titanate film is prepared on the SrTiO3 (001) substrate by using a sol-gel method with simple equipment and low cost, so that the dielectric constant of the film is improved, the dielectric loss is reduced, and the high dielectric property of the copper calcium titanate film is realized. According to the preparation method, the requirement on film preparation equipment is remarkably reduced, the repeatability is high, and the preparation method is suitable for preparing high-quality copper calcium titanate films on substrates with different shapes. The dielectric constant of the film material reaches 104, and the dielectric loss is as low as 0.01.

Provided are compositions and materials that have varistor properties and are suitable for use in electrical stress control devices and surge arrestor devices. The compositions and materials include a polymeric material and calcined calcium copper titanate filler material and have a reversible non-linear current-voltage characteristic.

The invention relates to a method for degrading antibiotics by using a double perovskite photocatalyst, i.e., calcium copper titanate. According to the method, a frequently used antibiotic, i.e., tetracycline, is used as a pollutant probe molecule, and xenon lamp irradiation is carried out in the presence of double perovskite photocatalyst calcium copper titanate (CaCu3Ti4O12) compounds with different morphologies so as to degrade the antibiotic. Degradation results show that the photocatalysis degradation efficiency of the antibiotic reaches 99% or above within 50 min; and results of high-performance liquid chromatography and high-resolution mass spectrometry prove that the antibiotic is eventually degraded into CO2 and H2O. The CaCu3Ti4O12 catalyst prepared in the invention presents high-grade photocatalytic activity in single photocatalytic degradation of organic pollutants and still has high photocatalytic activity after cyclically used a plurality of times. The method can substantially meet demands of application of clean energy and environmental treatment; and an experimental base is laid for innovation and progress of treating technologies for harmful substances in environmental treatment with a novel catalysis material and a novel catalysis technology as breakthrough points.

The invention discloses a calcium copper titanate-doped nonlinear silicone rubber composite material. The nonlinear silicone rubber composite material comprises a silicone rubber matrix material and a CaCu3Ti4O12 powder doped in the silicone rubber matrix material. The invention also discloses a preparation method of the calcium copper titanate-doped nonlinear silicone rubber composite material. The preparation method comprises the following steps: adding the CaCu3Ti4O12 powder to the silicone rubber raw material, fully mixing the CaCu3Ti4O12 powder and the silicone rubber raw material, placing the obtained mixture in a hot pressing die, and carrying out hot press molding to obtain the silicone rubber composite material with double nonlinear electrical properties. The nonlinear silicone rubber composite material is suitable for insulating parts working in extremely non-uniform electric field environment, has good self-adaptability to the electric field environment, and can effectively equalize the electric field, inhibit partial discharge and alleviate the aging of an insulating medium; and the material can keep good insulating characteristics in the low electric field strength region.

The invention relates to a high dielectric ceramic/PVDF composite material and a preparation method thereof, wherein the preparation method comprises the following steps: 1) preparing ceramic powder Ca1-xNixCu3Ti4O12; and 2) compounding: 2.1) dissolving polyvinylidene fluoride PVDF in N,N-dimethylformamide DMF to obtain a PVDF solution; 2.2) adding the prepared ceramic powder Ca1-xNixCu3Ti4O12 into the PVDF solution, and fully stirring for a period of time, to obtain a gelatinous mixed solution; and 2.3) coating the gelatinous mixed solution, and carrying out drying treatment to obtain the Ca1-xNixCu3Ti4O12/PVDF composite material. The technical problems of low dielectric strength and limited energy storage density of conventional dielectric ceramics are solved. The dielectric loss of theceramic is reduced by replacing the calcium ion in the calcium copper titanate ceramic by Ni dedoping.

The invention discloses a ceramic-based ternary composite material with weak negative dielectric property and a preparation method. The preparation method comprises the following steps: 1, respectively weighing titanium nitride, multi-walled carbon nanotubes and copper calcium titanate, then mixing, the mass of the multi-walled carbon nanotubes accounts for 6-12% of the total mass of the mixture, and crushing the mixture to obtain slurry; 2, drying the slurry, and grinding the solid to obtain powder; 3, adding polyvinyl alcohol into the powder, granulating the mixture, and carrying out dry pressing molding to obtain a green body; and step 4, sintering the green body to obtain the ceramic-based ternary composite material. Compared with metal materials, pure titanium nitride and the like, the negative dielectric constant of the titanium nitride/multi-walled carbon nanotube/copper calcium titanate ternary composite material prepared by the method is lower than 200 and can approach zero near a specific frequency, and the titanium nitride/multi-walled carbon nanotube/copper calcium titanate ternary composite material particularly has important application value in the aspects of high-power microwave devices, attenuation porcelain and the like in the military field. Besides, the preparation technology provided by the invention is simple and convenient in process, can realize batch production of products, and has a good technical transformation prospect.