48 results about "Graphene flake" patented technology

The application discloses a flexible terahertz metamaterial sensor and a preparation method thereof, which comprises, from top to bottom, a reinforcing layer, a carbon nanotube film layer and a polymer substrate layer; the reinforcing layer is composed of a graphene and zinc oxide composite material; the reinforcing layer and the carbon nanotube film layer are consistent in shape and are both periodic strip structures. The super material sensor is based on the synergistic effect of a ternary system of zinc oxide / graphene / carbon nanotube, wherein zinc oxide nanoparticles grow directionally on a graphene sheet through a Zn-O-C bond, and a carbon nanotube film constructs a three-dimensional conductive network, thus solving the dielectric loss problem of a traditional noble metal-based sensor structure. The phonon resonance characteristics of zinc oxide are coupled with graphene plasmons, a high-efficiency charge transfer channel is formed at a heterojunction interface, and the conductivity and terahertz transmission efficiency are improved.

The present invention relates to a planar heating element comprising: a heating layer including graphene flakes, functionalized graphene and a nanohybrid material; and an electrode electrically connected to the heating layer, wherein the nanohybrid material has the functionalized graphene self-adsorbed on the surfaces of thermally conductive inorganic particles.

Provided is a composite thin film current collector for a battery or supercapacitor, the thin film comprising graphene sheets dispersed in or bonded by an electron-conducting polymer network (also referred to as conducting network polymer, crosslinked polymer, or hydrogel polymer) wherein the composite thin film has a thickness from 2 nm to 500 μm and an electrical conductivity from 10−4 to 104 S / cm and wherein the graphene sheets occupy from 10% to 99% by weight and the polymer network from 1% to 90% by weight of the total composite weight.

This application provides a thermal conductive agent, its preparation method, and an elastomer. The preparation method includes: providing graphene material, an oxidant, and a polymer material; mixing the graphene material and the oxidant in a certain proportion to obtain a mixture; subjecting the mixture to mechanochemical treatment, cleaning, and drying to obtain edge-hydroxylated graphene; mixing the edge-hydroxylated graphene with the polymer material in a certain proportion and performing an exfoliation process to obtain the thermal conductive agent. Using the preparation method provided in this application, the oxidant can capture electrons from the edge carbons of the graphene under the action of mechanical energy, introducing hydroxyl functional groups at the edges of the graphene sheets. This improves the compatibility of graphene and the polymer material during subsequent exfoliation, while maintaining the complete π-π conjugated structure in the middle of the graphene, which is beneficial for the transport of electrons and phonons, giving the thermal conductive agent high thermal conductivity, high carrier mobility, and excellent mechanical strength.

This invention provides an anti-icing graphene component with electrothermal properties and its preparation method. The method involves: laser irradiating the surface of a diamond substrate to form several parallel graphite modules on the diamond substrate surface; mechanically cleaving the outer layer of the graphite modules to form a graphene layer in each graphite module, with the angle between the graphene sheets in the graphene layer and the diamond substrate surface being 30-40°; electrochemically exfoliating the graphene layer to reduce the angle between the graphene sheets in the graphene layer and the diamond substrate surface to 80-90°, forming a near-vertical graphene layer at the micro-nano scale; and finally, hydrophobic treatment to obtain the anti-icing graphene component with electrothermal properties. This invention, through a parallel electrothermal circuit composed of vertical graphene modules, effectively improves the electrothermal performance of the component, resulting in more uniform heating, a higher maximum steady-state temperature, and higher electrothermal conversion efficiency. Simultaneously, it possesses hydrophobic properties, better meeting the requirements of aircraft electrothermal anti-icing and de-icing.

A transparent or semi-transparent conductive thin film structure or pattern facilitating the insertion of dopant atoms, ions or molecules into a layered 2D material, the film structure comprising: a layered 2D material, an electrically insulating material, wherein the electrically insulating material is disposed below the layered 2D material, wherein the layered 2D material has at least one layer, wherein the layered 2D material is divided into islands of the 2D material, wherein the islands of the 2D material are spaced apart from each other by more than 0.5 nm and less than 1 meter, and wherein the islands of the 2D material are intercalation doped with at least one dopant, and wherein the at least one dopant comprises an intercalation dopant.

The application provides a graphene product with electrothermal performance and a preparation method, and the method comprises the following steps: performing laser irradiation treatment on the surface of a diamond substrate to form a high-orientation graphite layer on the surface of the diamond substrate; performing mechanical cleavage treatment on the outer layer of the high-orientation graphite layer to obtain a graphene layer formed by a plurality of graphene sheets, and the angle between the graphene sheets and the surface of the diamond substrate in the graphene layer is 30-40 degrees; and performing electrochemical exfoliation on the graphene layer, the pH of the electrolyte used in the electrochemical exfoliation is 9, the angle between the graphene sheets and the surface of the diamond substrate in the graphene layer is 80-90 degrees, a micro-nano scale nearly vertical graphene layer is formed, and the graphene product with electrothermal performance is obtained. The application also provides the product prepared by the above method. Compared with the prior art, the application can directly generate electrothermal graphene on the surface of the diamond in situ, and not only omits complex process steps such as reduction, but also has a service life far longer than that of ordinary graphene film electrothermal elements and excellent electrothermal performance.

A graphene-based thermally conductive film comprising a plurality of strips of a graphene film arranged so that graphene sheets of the graphene film are aligned in a direction perpendicular to the plane of the thermally conductive film, wherein the thermally conductive film comprises: a plurality of first area portions comprising strips of graphene film having a first rotational alignment in the plane of the thermally conductive film; and a plurality of second area portions comprising strips of graphene film having a second rotational alignment in the plane of the thermally conductive film, different from the first alignment.

The application discloses a high-conductivity and deep-low-temperature high-thermal-conductivity carbon film resistant to high-low temperature frequent alternation, characterized by comprising a carbon film body, the carbon film body serving as an electron donor, the carbon film body being composed of multiple layers of graphene sheet layers, a molybdenum chloride layer being inserted between two adjacent graphene sheet layers, and the molybdenum chloride layer being inserted between the graphene sheet layers in the form of an ionic compound and serving as an electron acceptor. The thermal conductivity of the carbon film can be as high as 4.6 times that of an original carbon film at deep low temperature. The carbon-based thermal-conductivity film has wide application prospects in the field of heat dissipation under extreme temperature such as aerospace and deep-sea exploration.

This invention relates to the field of metal surface treatment technology, specifically to tin-plated copper wire for preventing tin plating layer peeling and its production process. The production process of the tin-plated copper wire for preventing tin plating layer peeling includes: preparing a nano-alumina-pillared nano-graphene sheet composite material; pretreatment; pulse electroplating; post-plating washing; and passivation sealing. This invention first disperses carboxyl-modified graphene in anhydrous ethanol, then adds an aluminum source precursor. Electrostatic self-assembly allows the aluminum source to be adsorbed onto the graphene sheet surface. After acid-catalyzed gelation, aging, and calcination heat treatment, a nano-alumina-pillared nano-graphene sheet composite material is obtained. This composite material is then added together with polytetrafluoroethylene (PTFE) particles to a mixed tin plating solution. After pulse electroplating of the pretreated copper wire, the nano-alumina-pillared nano-graphene sheets and PTFE particles synergistically improve the bonding force between the tin plating layer and the copper wire substrate, thereby effectively preventing tin plating layer peeling.

A method for manufacturing phosphoric acid-based conductive particles for positive and negative electrodes, the method comprising the following steps: Step 500: taking multiple ceramic particles and a first alcohol aqueous solution, and mixing and grinding them using a grinder; Step 510: grinding the multiple ceramic particles to a size smaller than a certain value, then adding multiple lithium fluoride particles and organic materials to the grinder for further mixing and grinding to form a first mixed slurry; Step 520: taking a second alcohol aqueous solution, polyvinylpyrrolidone, sodium dodecyl sulfate, multiple first carbon nanotubes, and multiple graphene sheets, and thoroughly mixing them using a mixer to form a second mixed slurry; Step 530: adding the second mixed slurry to the grinder along with the first mixed slurry. Step 540: The above materials are taken out from the mill and placed in a vacuum concentrator to remove the first and second alcohol aqueous solutions to obtain a mixed powder; Step 550: The mixed powder is placed in a sintering furnace for sintering in a nitrogen atmosphere, and the temperature is gradually increased to a specific temperature to obtain the multiple conductive particles. The organic materials, polyvinylpyrrolidone, and sodium dodecyl sulfate will form multiple amorphous carbons under oxygen-free sintering. These multiple amorphous carbons will form an amorphous carbon layer covering the outer surface of each ceramic particle, and the multiple lithium fluoride particles, the graphene sheets, and the first carbon nanotubes will be distributed in the amorphous carbon layer to form multiple conductive particles.

This invention relates to the field of graphene and discloses a method for preparing highly dispersible graphene oxide with a high monolayer ratio at low temperatures. The method includes: S1: ball milling a mixture of graphite and activated carbon; S2: immersing the graphite / activated carbon mixture in an acidic solution containing hypochlorous acid and / or hypochlorite under light irradiation for a pre-oxidation reaction to exfoliate the graphite into a monodisperse state; S3: oxidizing the product of reaction S2 in a concentrated sulfuric acid / perchloric acid mixed acid system; S4: diluting the product of reaction S3 with water and then introducing a ferrous salt for a reduction reaction; and finally, separating and washing to obtain a graphene oxide dispersion. This invention can prepare highly dispersible graphene oxide with a high monolayer ratio under low temperature and mild conditions. Furthermore, during the preparation process, this invention utilizes the synergistic effect of activated carbon and chloride ions to fully disrupt the large π bonds of the conjugated aromatic domains in graphite, thereby increasing the flexibility of the graphene sheets and reducing viscosity.

The present application relates to a kind of high flexibility flame-retardant composite, bundled cable and its preparation method, belong to cable material technical field, by hydrothermal method synthesis CoFe2O4 Nanoparticle, then it is compounded with graphene oxide, copper nanowire, forms three-dimensional porous composite aerogel, after ultrasonic stripping, graphene oxide sheet layer forms stable conductive framework, the melting point of copper nanowire is higher, can keep continuous conductive network structure in high temperature heat treatment, avoid melting agglomeration, interface combination is more stable, CoFe2O4 Nanoparticle is embedded in sheet layer gap, realizes interface close combination after high temperature heat treatment, graphene oxide strengthens network continuity, copper nanowire is generated by reflection electromagnetic wave conductive loss, and the magnetic hysteresis loss of CoFe2O4 Nanoparticle forms complement, in wide frequency range, shielding effectiveness fluctuation is smaller, can effectively resist the interline electromagnetic coupling of strong electricity, weak electricity when bundled laying, guarantee signal transmission stability.

The present application relates to a kind of curvature gradient superstructure evaporative casting induced light high-strength structural materials, specifically, a kind of graphene-based superstructure material is disclosed, the graphene-based layer of the material is internally by graphene sheet layer in curvature gradient way interlock, tightly arranged composition.This material is light and high-strength.

A method for preparing a graphene-based composite includes the steps of: providing graphene films; aligning and stacking the graphene films along a first direction perpendicular to surfaces of the graphene films, followed by conducting a hot pressing treatment at a pressure ranging from 10 kg / cm2 to 12 kg / cm2 to allow the surfaces of the graphene films to fuse with each other, so as to form a graphene laminated structure; cutting the graphene laminated structure along the first direction or a second direction that is parallel to the first direction and that is oriented oppositely to the first direction, so as to obtain a graphene sheet having a cutting surface; and depositing copper onto the cutting surface of the graphene sheet by a sputtering process to form a copper film on the graphene sheet, so as to obtain the graphene-based composite.

A process for producing a graphene reinforced aluminum metal matrix composite material, including the steps of providing a flowable aluminum material, combining multiple flattened sheets of graphene or a graphene powder with the aluminum material, and processing the combination to create the aluminum metal matrix composite material incorporating the graphene and orienting the graphene to enhance conductivity. A current carrying article providing high conductive properties is also disclosed and includes an aluminum metal matrix composite combined with an oriented graphene in order to achieve enhanced electrical conductivity.

The application belongs to the technical field of thermal interface materials, and particularly relates to a graphene foam composite heat-conducting gasket, a preparation method thereof and an electronic device. The composite heat-conducting gasket comprises a graphene foam core body. The preparation process of the graphene foam core body comprises the following steps: after the graphene foam is loaded with nano liquid metal particles, the graphene foam is subjected to nano liquid metal vapor welding treatment in a closed space, so that the nano liquid metal forms metal welding points in situ at graphene sheet layer joint nodes. The graphene foam is used as the core body, the nano liquid metal particles are loaded, and the metal vapor welding treatment is performed in the closed space, so that the nano liquid metal forms the metal welding points in situ at the graphene sheet layer joint nodes, and the structural strength of the graphene foam is significantly improved. Then, the adhesive is coated, and the layers are subjected to heat pressing and compounding, so that an integrated laminated structure is formed. The heat-conducting gasket prepared by the application meets the heat dissipation requirement of high heat flow density electronic devices.

This invention relates to the field of flame-retardant composite materials, specifically to flame-retardant composite materials based on the synergistic reinforcement of talc and graphene sheets and their applications. It addresses the problem that existing polymer materials struggle to simultaneously achieve reinforcement, flame retardancy, and lightweighting, and require large quantities of high-performance additives. The process involves first mixing talc sheets, graphene, a composite flame retardant, and a dispersant in a high-speed mixer, then cooling to room temperature to obtain a premix. A polymer matrix is ​​then added to a twin-screw extruder. The premix and other auxiliary additives are added through a side feed port, melt-blended, water-cooled, air-dried, and pelletized to obtain composite material particles. These particles are then vacuum-dried and injection-molded to obtain the flame-retardant composite material. The flame-retardant composite material possesses excellent flame-retardant and mechanical properties, exhibiting outstanding overall performance and being more suitable for industrial production.

The present application relates to the technical field of advanced inorganic non-metallic material preparation, and particularly relates to a wet compounding preparation process of graphene modified conductive thermoplastic polyurethane. The present application provides a solution to the problems in the prior art, such as easy agglomeration of graphene filler, mechanical performance decline caused by increased filler addition, insufficient anisotropic regulation of thermal / electric conductivity, large amount of organic solvent, high recovery cost, and complex process difficult to be continuous; graphene oxide and TPU emulsion are dispersed, oriented and arranged in a low-boiling azeotropic solvent through microfluidic laminar shear; then, a vertical ice crystal template is constructed by using directional-bidirectional freezing technology, and the freeze-dried material is selectively photothermally reduced by using 808nm laser pulses, polydopamine is introduced on the surface of GO, and silver nanowires are filled in the interlayer gap of graphene sheets to realize a multi-scale conductive network. Finally, the performance of the composite material is improved and the process is optimized.

This invention relates to the field of fuel additive technology, specifically to a nano-magnesium hydride-attapulgite composite fuel additive and its preparation method. The additive consists of nano-magnesium hydride, a modified attapulgite carrier, and a cerium-based combustion-supporting catalyst, with a mass ratio of 1:(5-20):(0.01-0.1). The modified attapulgite carrier is a surface-grafted graphene-coated composite carrier material. This application achieves anchoring by isolating nano-magnesium hydride particles through a physical barrier network of graphene sheets and by overcoming the strong chemical interaction between the grafted functional groups and nano-magnesium hydride, thus solving the core problems of unstable dispersion, easy agglomeration and deactivation, and insufficient carrier compatibility and anchoring ability. Under the high-temperature environment of the combustion chamber, the highly active hydrogen species released by the decomposition of nano-magnesium hydride can hydrogenate and crack fuel macromolecules and soot precursors, accelerating the combustion chain reaction. The cerium-based compounds provide continuous active oxygen for deep oxidation of soot through their oxygen storage and release function.

The application provides a high-wear-resistance self-lubricating high-speed ball bearing retainer, which comprises a retainer body and a microcapsule wear-resistant lubricating coating coated on all surfaces of the retainer body; the retainer body is made by multiple times of impregnation, solidification and molding processing of plain cotton cloth with alcohol-soluble linear phenolic resin; the microcapsule wear-resistant lubricating coating is made by mixing film-forming resin, lubricating oil microcapsules, wear-resistant fillers and diluents; the lubricating oil microcapsules are core-shell structure microcapsules with urea-formaldehyde resin coated lubricating oil, and the graphene oxide has a diameter of 1-5 mu m and a thickness of 2-3 nm. In view of the defects of the prior art, the application provides a high-wear-resistance self-lubricating long-service-life high-speed ball bearing retainer with higher strength and stronger stability and a preparation method thereof.

The application relates to the technical field of graphene and discloses a graphene dispersion liquid preparation method based on ultrasonic assistance, which comprises the following steps: mixing graphene powder, a solvent, nano-silicon dioxide, a dispersion catalyst, a stabilizer and a reducing agent to form a preliminary mixture; pretreating the preliminary mixture with a surface modifier; applying ultrasonic treatment to the preliminary mixture for 5-60 minutes; filtering and centrifugally separating the mixture after the ultrasonic treatment, removing undispersed particles, and obtaining a graphene dispersion liquid with excellent stability and dispersion efficiency; by adding nano-silicon dioxide, the surface characteristics of the nano-silicon dioxide are used to enhance the space stability between graphene sheet layers, and the graphene sheet layers are prevented from re-agglomerating. The dispersion catalyst accelerates the dispersion process and improves the dispersion efficiency. The pretreatment step of the surface modifier significantly improves the affinity between the graphene and the solvent, and further promotes the uniform dispersion of the graphene.

The application discloses a graphene flake cutting device, and belongs to the technical field of cutting devices. The technical scheme points of the graphene flake cutting device are as follows: a support comprising a guide roller; two shaft bodies installed on the support; the shaft bodies are provided with a plurality of roller bodies; an upper cutter assembly installed on one of the shaft bodies, the upper cutter assembly comprising an upper cutter body and an upper cutter holder; a lower cutter assembly installed on the other shaft body, the lower cutter assembly comprising a lower cutter body and a lower cutter holder; the upper cutter holder and the lower cutter holder are respectively sleeved on the two shaft bodies and abut against the roller bodies; the two ends of the shaft body are provided with sleeve seats abutting against the roller bodies or the upper cutter holder or the lower cutter holder; the sleeve seats are used for limiting the movement of the roller bodies, the upper cutter holder and the lower cutter holder along the axis of the shaft body; and a cutting gap is arranged between the lower cutter body and the lower cutter holder. The graphene flake cutting device can cut the flake.

A graphene composite conductive material and a preparation method thereof, the graphene composite conductive material is prepared from the following raw materials in parts by weight: 12-25 parts of MnO2 / graphene composite material, 15-25 parts of graphite powder, 35-50 parts of polymer resin, 1-8 parts of filler. By utilizing the large specific surface area of graphene, it enhances electron migration efficiency; not only does this facilitate the uniform growth of MnO2 particles on the graphene sheets, but the uniform loading of MnO2 also prevents the aggregation and stacking of graphene sheets during the composite process; graphite powder and graphene layer form an effective conductive path; the functional groups on the surface of graphene and MnO2 can chemically bond with the polymer resin molecular chains to enhance the interfacial interaction; the filler, with high strength and modulus, serves as reinforcing phases to enhance mechanical properties of the graphene composite conductive material.

This invention relates to the field of graphene powder preparation and discloses a process for preparing graphene powder for the negative electrode of an energy storage battery. The process includes: mixing graphene oxide powder, an inorganic eutectic salt precursor, and a strong reducing agent to prepare a reaction precursor; controlling the material system across the eutectic temperature range and maintaining a constant temperature; utilizing the latent heat of phase change in the melting salt component to absorb the exothermic deoxidation reduction, allowing the molten salt liquid phase to penetrate into the graphite interlayer; repairing the carbon lattice at high temperature and controlling the cooling rate to induce in-situ precipitation of submicron-sized microcrystals from the liquid phase. This invention ensures lattice integrity through a thermodynamic hedging mechanism and dissipates crystallization stress through a microcrystallization locking mechanism, preventing irreversible agglomeration of graphene sheets, ensuring the powder maintains a three-dimensional open topological morphology, and improving the initial discharge specific capacity of the energy storage electrode active material.

This invention provides a hydrophobic and anti-corrosion composite material, its preparation method, and its application, relating to the field of coating materials technology. The hydrophobic and anti-corrosion composite material, by weight, comprises or is prepared from raw materials comprising the following components: polyphenylene sulfide resin: 68-90 parts; polysilazane-modified fluorinated graphene composite filler: 10-30 parts; compatibilizer: 2-4 parts; antioxidant: 0.1-0.5 parts; lubricant: 0.5-1.5 parts; optionally, corrosion inhibitor: 0.5-5 parts; wherein the raw materials for the polysilazane-modified fluorinated graphene composite filler include fluorinated graphene and polysilazane, with a weight ratio of fluorinated graphene to polysilazane of 1:(1-1.8). In the hydrophobic and anti-corrosion composite material provided by this invention, polysilazane chemically bonds with the PPS matrix and compatibilizer, and the polysilazane coating layer effectively inhibits the aggregation of fluorinated graphene sheets, achieving a synergistic unity of strength, toughness, and adhesion.

The present application relates to the plating technology field of metal material, disclose a kind of plating process of metal substrate surface heavy anticorrosive coating, comprising: to metal substrate is implemented hydroxylation activation treatment, and is coated with the anticorrosive coating including siloxane modified graphene, polyurethane prepolymer and high-boiling organic solvent;Utilize normal temperature stationary induction active siloxane functional group and metal hydroxyl functional site occur polycondensation reaction, and in situ covalently anchored single-layer graphene directional template is constructed in metal interface;Through gradient temperature curing drive solvent unidirectional migration and the normal mechanical shear force generated by polyurethane volume limited shrinkage, guide non-anchor graphene sheet layer to arrange parallel to substrate with the directional template as benchmark, the present application constructs continuous maze shielding structure in coating interior by the synergistic effect of chemical anchoring and physical calendering, inhibit corrosion medium penetration, enhance interface bonding force and stability.