1055 results about "Porous graphene" patented technology

The invention discloses a graphene with a porous structure and a preparation method of the graphene. The porous grapheme consists of a single-layer or multi-layer graphene structure unit, the single-layer or multi-layer grapheme structure unit has a pore-shaped structure (pore diameter is 0.1-200 nm) and a large specific surface area (300-2000 m<2> / g), thus the graphene has potential application value in the aspects of super-capacitors, conductive filling materials and the like. The preparation method of the porous grapheme is characterized in that MgO, Mg(OH)2, Al2O3, Al(OH)3, hydrotalcite compounds and / or corresponding calcined products of the substances are used as catalysts, or MgO, Mg(OH)2, Al2O3, Al(OH)3, hydrotalcite compounds and / or corresponding calcined products of the substances are used as carriers so as to further load one or more active components of Fe, Co, Ni and Mo and then the obtained substance is used as the catalyst ( the pore diameter of the catalyst is 1-200 nm, and the specific surface area is 10-300 m<2> / g); and then at the temperature of 300-1000 DEG C, the graphene is prepared by using inert gases such as nitrogen, argon, helium and the like and using a hydrocarbon chemical gas phase deposition method.

The invention discloses a porous graphene / polymer composite structure, and a preparation method and application thereof. The composite structure mainly comprises a compound formed by porous graphene and more than one polymer and / or polymer monomer. The preparation method comprises the following steps of: compounding polymers and / or polymer monomers with porous graphene to form a target product, wherein the compounding manner comprises single-screw / double-screw fusing processing, injection molding, blow molding, melt spinning, solution spinning, electrostatic spinning, electrostatic spraying, powder metallurgy, liquid mixing or high speed mechanical stirring dispersion. The invention is simple in process, wide in source of raw materials, easy to implement in large scale, low in cost, safe, environment-friendly and free from toxic and harmful wastes, and the product obtained is excellent in thermal and electric properties, and has wide application prospect in the fields of heat conduction, radiation, electric conduction, anti-static electricity, electromagnetic shielding and the like.

The invention provides a preparation method for three-dimensional porous graphene for a supercapacitor. The preparation method comprises steps as follows: ultrasonically dispersing graphene oxide; fully mixing with a strong alkali solution; pre-drying until a surface is humidified; then activating at a vacuum environment at 120 to 180 DEG C or in protective gas atmosphere at 180 to 1200 DEG C under a high temperature; and etching the surface of the graphene to obtain a three-dimensional porous structure through high-temperature strong alkali and stream, so as to improve a specific surface area of a graphene material. According to the preparation method, activated graphene oxide is reduced through chemical reduction and high-temperature reduction methods, so as to improve a performance of activated graphene. The activated graphene and an adhesive are mixed to prepare into electrode paste based on a certain mass ratio, and the electrode paste is loaded on a conductive current collector to prepare into a supercapacitor electrode, so that a degree of agglomeration of the graphene on a pole piece can be further reduced, and a high electrochemical performance can be obtained.

The invention discloses a porous graphene loaded cerium nano composite antibacterial agent which is compounded from porous graphene and cerium, wherein nano cerium is deposited on a porous graphene layer; the particle size of the nano cerium is within 5-20nm; the specific surface area of the porous graphene is 350-450m<2> / g; the conductivity of the porous graphene is 20-60S.m<-1>; and the weightlessness of the porous graphene within 900 DEG C is 4-6wt%. The invention further discloses a preparation method of the porous graphene loaded cerium nano composite antibacterial agent. The method comprises the preparation of the porous graphene and the preparation of the porous graphene loaded cerium. The porous graphene loaded cerium has longer antimicrobial activity, can improve the security and reduce the use cost, and has wide prospects in industrial applications.

The invention belongs to the field of adsorbing materials, and relates to an inorganic-inorganic hybrid material, particularly a graphene / clay composite material. The composite material is powdery, is compounded from porous graphene and clay, and has a porous structure; the porous graphene is inserted among clay layers through intercalation reaction; the mass ratio of the porous graphene to the clay is 1:(0.1-10); the specific area of the graphene / clay composite material is 200-250 m<2> / g, and the weight loss within 900 DEG C is 3-6 wt%; and the clay is montmorillonite, vermiculite, illite, kaolin or rectorite. The graphene / clay composite material can be easily dispersed, can be used for comprehensively and efficiently adsorbing heavy metals and organic substances, and has the characteristics of high dispersity and efficient and selective adsorbability for heavy metals and organic substances; the maximum comprehensive removal rate can reach 99%; and thus, the invention has wide prospects in industrialized application.

The invention provides a method for preparing active porous graphene. The method comprises the following steps: 1) bleaching cellulose by use of hydrogen peroxide to obtain a first intermediate product; 2) activating the first intermediate product by use of an activating agent to obtain a second intermediate product; 3) performing carbonization treatment on the second intermediate product at 600-1100 DEG C to obtain the active porous graphene. The invention aims to provide a method for preparing active porous graphene, and the active porous graphene prepared from the method provided by the invention has better conductivity and has better dispersity.

The invention provides a three-dimensional graphene / phase change energy storage composite material and a preparation method thereof. The technical scheme is as follows: graphene and a phase change energy storage material are in situ compounded, wherein porous graphene with a three-dimensional structure is used as a heat conductor and a compound die, and a solid-liquid phase change organic material is used as the energy storage material and filler. The three-dimensional porous graphene is compounded with the phase change material, the phase change energy storage material is partitioned in a plurality of pore spaces and is in tight joint with the graphene wall so as to greatly increase the effective heat contact area, and the highly linked graphene three-dimensional heat conduction network channels can realize rapid system heat exchange. In addition, due to the capillary adsorption capacity of porous graphene, the liquid-state phase change energy storage material is localized, so as to effectively prevent seepage. Therefore, the three-dimensional graphene foam has good designability, and becomes a lighter and more effective heat dissipation material for electronic devices.

The invention provides a preparation method of porous graphene. The method comprises the steps of: heating a carbon material and an activator; obtaining the porous graphene after reaction, wherein the carbon material is modified graphene or graphene, and the activator is a transitional metal or a transitional metal compound; in the process of preparing the porous graphene, heating the graphene or the modified graphene and the activator: the transitional metal or the transitional metal compound to form a transitional metal carbide; further decomposing the transitional metal carbide into carbon and transitional metal to obtain the transitional metal for continuously reacting with the graphene; and circulating in this way to finally obtain the porous graphene. Compared with the prior art, as the transitional metal and the carbon material are reacted circularly, the porous graphene with larger aperture range can be obtained. Experimental result shows that the diameter of the porous graphene prepared by the invention is 1-100nm.

The invention relates to a graphene radiating apparatus. The radiating apparatus comprises a first radiating layer (10) and a substrate (20), wherein the substrate (20) adopts a two-dimensional or three-dimensional structure and is provided with a first surface and a second surface opposite to the first surface, wherein the radiating layer (10) arranged on the first surface is formed by porous graphene, at least one kind of polymer and / or a compound formed by polymer monomers; and a multi-layer structure at least including a first film layer (210), a second film layer (220), a third film layer (230), a fourth film layer (240) and a fifth film layer (250) is arranged on the second surface. The invention also relates to a preparation method for the graphene radiating apparatus. The graphene radiating apparatus provided by the invention has the advantages of simple structure, high thermal conductivity and thermal dissipation, and wide application range.

The invention relates to a non-metallic bi-functional oxygen catalyst for graphene / nickel iron type hydrotalcite as well as a preparation method and electric catalytic application thereof to oxygen evolution reaction and oxygen reduction reaction in an alkaline medium. The catalyst takes a micelle as a template, and under the hydrothermal and reducing conditions, the nickel iron type hydrotalcite is assembled onto graphene in sequence to form a spherical porous graphene oxide / nickel iron type hydrotalcite compound. The method comprises the following steps: dispersing graphene oxide and metal salt in the micelle, introducing an alkali source, synthesizing the graphene oxide / nickel iron type hydrotalcite compound under the hydrothermal conditions, and performing hydrazine hydrate reduction on an obtained product to obtain the catalyst. The catalyst prepared by the method has high oxygen evolution and oxygen reduction catalytic activity, good stability and excellent methanol tolerance under the alkaline conditions and is low in cost of raw materials used, simple in preparation method, easy to operate and convenient for large-scale production.

The invention belongs to the field of carbon materials and electrochemistry, and discloses a heteroatom-doped porous graphite electro-catalyst and preparation and application thereof as well as a device. The method comprises the following steps: firstly adding concentrated HNO3 into a graphite oxide aqueous solution, performing sealing, ultrasonic reaction and stewing, and pouring the solution into deionized water for centrifugation, filtering and drying to obtain graphite oxide with holes in the surface; uniformly mixing the graphite oxide with holes in the surface, a heteroatom-doped source compound and a solvent to obtain a mixture, coating the surface of a substrate with the mixture, and performing freeze drying to obtain a solid thin film; putting the substrate loaded with the solid thin film into a plasma high-temperature tubular reactor for reaction to obtain the heteroatom-doped porous graphite electro-catalyst. The prepared electro-catalyst is higher in oxygen reduction electro-catalytic performance and is higher in electrochemical performance when applied in an electrode material; the electro-catalyst can be applied to the field of proton exchange membrane fuel batteries, direct alcohol fuel batteries and metal-air battery anode materials.

A method of producing a pre-sulfurized active cathode layer for a rechargeable alkali metal-sulfur cell; the method comprising: (a) Preparing an integral layer of porous graphene structure having a specific surface area greater than 100 m2 / g; (b) Preparing an electrolyte comprising a solvent and a sulfur source; (c) Preparing an anode; and (d) Bringing the integral layer and the anode in ionic contact with the electrolyte and imposing an electric current between the anode and the integral layer (serving as a cathode) to electrochemically deposit nano-scaled sulfur particles or coating on the graphene surfaces. The sulfur particles or coating have a thickness or diameter smaller than 20 nm (preferably <10 nm, more preferably <5 nm or even <3 nm) and occupy a weight fraction of at least 70% (preferably >90% or even >95%).

The invention relates to a preparation method of a foamed porous graphene / polypyrrole composite oil absorption material, belonging to the technical fields of environmental protection and composite materials. The method is characterized by comprising the following steps: carrying out KH570 functionalization on graphite oxide prepared from graphite; carrying out ultrasonic treatment on the functionalized graphite oxide product to obtain a graphene oxide aqueous solution with a certain concentration, adding certain amounts of pyrrole, styrene or butyl methacrylate or lauryl methacrylate and an initiator (ammonium persulfate or potassium persulfate); carrying out thermostatic reaction in a hydrothermal reaction kettle for 10 hours, thereby obtaining a black solid; and carrying out freeze-drying on the black solid to obtain the foamed porous graphene / polypyrrole composite oil absorption material in a three-dimensional structure. The graphene / polypyrrole composite oil absorption material ina three-dimensional structure is prepared by a chemical process, so the material has hydrophobicity and large specific area of the graphene, can contain abundant oil molecules, and has high oil adsorbability. The preparation method is simple to operate, and has the advantage of mild reaction conditions.

The invention relates to a graphene macroscopic body / a tin oxide composite lithium ion battery anode material and a process thereof. The anode material consists of a three-dimensional graphene macroscopic body and nano tin dioxide which grows in a pore of the three-dimensional graphene macroscopic body in an orientated way; and a volume is 500 to 2,000 mAh / g; the coulomb efficiency is 80 to 99.5 percent, wherein a mass ratio of the three-dimensional graphene macroscopic body to the tin dioxide is 1:(0.1-20). The characteristic of high electric conductivity of graphene is kept, the transfer and transport of charges are facilitated, and microscopic and macroscopic electric network structures are formed; meanwhile, the three-dimensional graphene macroscopic body has a big specific surface area and abundant pore spaces, so that the transfer of lithium ions is facilitated, and the contact area of the electrode material and electrolyte is enlarged; and the preparation process is environment-friendly, pollution-free and suitable for industrial production.

The invention discloses a method for preparing a three-dimensional porous graphene material by solution. The method comprises the following steps of: immersing a three-dimensional porous template into a graphene oxide solution, and then depositing the graphene oxide on the template to realize three-dimensional assembling of the graphene oxide on the template, and then preparing the three-dimensional porous graphene material containing the template by reduction; removing the template from the three-dimensional porous graphene material containing the template, and then washing to obtain the three-dimensional porous graphene material. The aperture of the three-dimensional porous graphene material can be regulated and controlled by using the templates with different apertures the material prepared by the invention has the advantages of low density, high specific surface area, high heat conductivity, high-temperature resistance, and corrosion resistance; the preparation method is economical and simple and suitable for large-scale production. And the prepared material is applicable to aspects such as catalytic carriers, preparation of flexible conductors, and stretchable electronics.

The invention relates to a porous grapheme / MnO2 composite film and a preparation method and application thereof. The preparation method comprises the following steps of (1), providing a ball-shaped formwork and coating the surface of the ball-shaped formwork with a polymer layer; (2) providing graphene oxide solution, evenly mixing a small formwork ball coated with the polymer layer obtained in the step (1) with the graphene oxide solution, performing vacuum filtration, and stripping the composite film from a filter membrane after drying; (3) performing high temperature annealing on the composite film obtained in the step (2) to obtain a film of a porous structure; (4) putting the film obtained in the step (3) into potassium permanganate solution to perform hydrothermal reaction to obtain the porous grapheme / MnO2 composite film. No any binder or conductive agent is needed to be added to the porous composite film prepared by the method, and the porous composite film is good mechanical property and super capacitive performance, has the advantages of being good in high-rate charge and discharge performance, long in circle life and the like, and can be applied to preparing super-capacitors and improve performance of super-capacitors greatly.

The present invention provides composite material having a porous graphene-based foam matrix and comprising porous inorganic micro-particles and metal oxide nano-particles distributed throughout the foam matrix.

The invention discloses a preparation method for a three-dimensional porous graphene doping and coating lithium titanate composite anode material. The problem that a high ratio property of lithium titanate is poor can be solved by a doping vario-property of a carbon nano material to the lithium titanate, and the spinel structure of the lithium titanate can not be affected. A nano carbon layer made of the carbon nano material is doped in a carbon nano material doping lithium titanate composite material to have an effect of an electrical transmission cushion layer, so that a cyclic property of the carbon nano material doping lithium titanate composite material is improved, besides, an introduction of the carbon nano material can effectively restrain a gathering of lithium titanate particles in a heat treatment process, and simultaneously diffusion coefficients of lithium-ions in the carbon nano material doping lithium titanate composite material are increased. According to the preparation method for the three-dimensional porous graphene doping and coating lithium titanate composite anode material, the prepared three-dimensional porous grapheme has a high specific surface area, and thereby the high ratio property of the lithium titanate is further improved.

The invention relates to a novel porous graphene or a graphene / porous metal composite material, and preparation methods of the porous graphene and the composite material. The preparation method of the composite material comprises the following steps: blending metal powder and / or metal oxide powder, blade-coating to form a film, and carrying out high temperature reduction in a reducing atmosphere to form a three-dimensional porous metal substrate; and growing graphene through adopting a chemical vapor deposition process to obtain the graphene / porous metal composite material. The material is a graphene composite material and has a wide application prospect. The preparation of the porous graphene or the graphene / porous metal composite material has an original creativity and is of positive scientific significance.

The invention discloses a lithium-sulfur battery. The lithium-sulfur battery comprises three-dimensional porous graphene covalence fixing nanometer lithium sulfide as a composite positive electrode, a polyolefin membrane coated with graphene oxide as a modified membrane, and a lithium sheet negative electrode and an electrolyte which are generally adopted. The particle size of lithium sulfide in the composite positive electrode is between 1 nm and 100 nm, and the lithium sulfide is combined with oxygen-containing functional groups on the surface of three-dimensional porous graphene in the form of a C-O-S covalent bond. The modified membrane is prepared from graphene oxide with the thickness of 0.1 to 10 microns uniformly deposited on the surface of a traditional polyolefin membrane; and the graphene oxide can be coated on both sides of the polyolefin membrane, and can also be coated on the side facing the lithium sulfide positive electrode when the battery is assembled. According to the lithium-sulfur battery disclosed by the invention, the dissolution of the sulfur positive electrode can be effectively prevented, the shuttle effect is inhibited, the overpotential of the battery is reduced, the structural damage generated by positive electrode volume expansion is avoided, and the rate characteristic and cycle performance of the lithium-sulfur battery are substantially improved.

The invention discloses porous graphene and a graphene quantum dot. The porous graphene comprises, but is not limited to 2-9 atomic layers, wherein each atomic layer simultaneously comprises crystal lattices and holes of graphene, but is not limited to the holes of which the apertures are 2-10nm; the area of the holes accounts for about 5%-40% of total area of each atomic layer. The graphene quantum dot is characterized by comprising 1-5 atomic layers; the boundary is in a sawtooth shape; and the dimension of the quantum dot is 2-10nm. The porous graphene disclosed by the invention is uniform in aperture distribution, and not equal in interlayer spacing; and the graphene quantum dot has the advantages of high luminous efficacy, good crystal form and few defects.

The invention provides a method for preparing a porous graphene material. The method comprises the following steps of: (1) dispersing nano granules of a metal oxide into a solvent; (2) adding a soluble salt of a graphitization catalyst and a polymer into the product obtained in the step (1), and performing uniform mixing; (3) heating and vacuumizing the product obtained in the step (2) to remove the solvent; (4) thermally treating the product obtained in the step (3) for 0.5 to 400 minutes in inert atmosphere at the temperature of between 500 and 1,000 DEG C, and collecting a solid product after cooling; and (5) treating the solid product by using dilute acid to dissolve and remove the catalyst and the nano granules of the metal oxide so as to obtain the porous graphene material. The porous graphene material prepared by using the method has low oxygen content and high graphitization degree, and holes with diameter of more than 2 nanometers are distributed on the graphene sheet layer. The preparation method is simple, the raw materials are easily obtained, and the preparation method can be used for batch preparation and is easy to realize industrialized production.

The invention belongs to the field of preparation of nanometer materials, and provides a method for preparing a nitrogen and phosphorus codoped porous graphene material. The nitrogen and phosphorus codoped porous graphene material is prepared by taking phosphorus-containing polyion liquid microgel as a novel soft ball template and phosphorus-doped precursor, and ammonium hydroxide as a nitrogen source and another pore-forming agent. The prepared porous graphene material has a thin pore wall, large specific surface area and pore diameter, uniform and stable properties, and has potential application prospect in fields such as supercapacitors, security check and catalysis. According to the method, the source of raw materials is wide; the method is simple and easy to operate, is beneficial for mass production in large scale, and has good industrial production basis and wide application prospect.

The invention aims at providing a method for preparing graphene from a three-dimensional porous carbon material and three-dimensional porous graphene. The invention adopts the technical scheme that according to the method, a carbon atom of the three-dimensional porous carbon material is activated by using a high-activity hydrogen plasma; and the carbon atom of a foreign carbon source is captured by using high-activity carbon, so that the carbon atom is grown to form the three-dimensional porous graphene and the further the three-dimensional porous graphene is obtained. According to the method for preparing graphene from three-dimensional porous carbon material, which is disclosed by the invention, three-dimensional porous amorphous carbon or three-dimensional porous graphene material is directly grown and converted into the high-quality three-dimensional porous graphene without damaging the three-dimensional porous structure of the three-dimensional porous graphene, so that a pore canal is stable; and the prepared three-dimensional graphene has higher conductivity and can be widely applied to new energy devices such as solar cells, super capacitors and lithium ion batteries.

A scalable method allows preparation of bulk quantities of holey carbon allotropes with holes ranging from a few to over 100 nm in diameter. Carbon oxidation catalyst nanoparticles are first deposited onto a carbon allotrope surface in a facile, controllable, and solvent-free process. The catalyst-loaded carbons are then subjected to thermal treatment in air. The carbons in contact with the carbon oxidation catalyst nanoparticles are selectively oxidized into gaseous byproducts such as CO or CO2, leaving the surface with holes. The catalyst is then removed via refluxing in diluted nitric acid to obtain the final holey carbon allotropes. The average size of the holes correlates strongly with the size of the catalyst nanoparticles and is controlled by adjusting the catalyst precursor concentration. The temperature and time of the air oxidation step, and the catalyst removal treatment conditions, strongly affect the morphology of the holes.

The invention provides a grading three-dimensional porous graphene / titanium dioxide photocatalyst and preparation method thereof. The photocatalyst is composed by a three-dimensional grapheme framework and nano titanium dioxide particles; the grahene is provided with a macroporous structure; titanium dioxide is mesoporous titanium dioxide; the macropores and the mesopores are communicated; the nano titanium dioxide particles are scattered on a grapheme nano sheet; the surfaces of nano titanium dioxide microspheres are wrapped with graphene nano sheets; the macropores of the graphene are filled with the nano titanium dioxide microspheres. The photocatalyst with a three-dimensional structure can not only prevent the graphene sheet layers from stacking, but also scatter titanium dioxide particles excellently, and is high in specific surface area; besides, samples can be used for photocatalysis degradation of methylene blue, and the methylene blue can be fully degraded in 25 minutes. The preparation method provides a new thought for preparation of the photocatalyst, and has a potential application value in the fields of energy sources and environment.

A preparation method of a heteroatom doped graphene hierarchical pore carbon material comprises the following steps: preparing graphene micro-sheet dispersing liquid by using graphene, then carrying out pore-forming etching on graphene micro-sheets in the graphene micro-sheet dispersing liquid, and preparing porous graphene micro-sheets; mixing the porous graphene micro-sheets with a fatty acid metal compound coating agent and a dopant to obtain oil-phase viscous graphene-based precursor; carrying out programmed heat treatment; carrying out acid pickling, water washing and solid-liquid separation on a product after heat treatment, and drying solid to obtain the final product. The preparation method has the advantages of low cost, simple process, low energy consumption, wide raw material source, and capability of large-scale production.

The invention discloses a nitrogen-doped three-dimensional nano porous carbon / porous graphene composite material and a preparation method thereof on the basis of a hydrothermal method. The preparation method includes: adsorbing a ZIF (zeolitic imidazolate framework) material onto GO (graphene oxide) to form GO / ZIF; adding an etching agent into a GO / ZIF ethanol solution to realize hydrothermal reaction, and enabling GO reduction in the reaction process along with GO etching and assembly of a three-dimensional network structure to obtain a ZIF / porous graphene three-dimensional structure; performing carbonation reaction to enable ZIF carbonation to form porous carbon loaded on the surface of a graphene lamella in the three-dimensional structure, and allowing nitrogen in ZIF to be doped in a graphene network to obtain the nitrogen-doped three-dimensional nano porous carbon / porous graphene composite material. The nitrogen-doped three-dimensional nano porous carbon / porous graphene composite material is high in specific surface area and catalytic activity, and the preparation process based on the hydrothermal method is simple in operation and high in repeatability.

The invention discloses a method for directly preparing a co-doping three-dimensional graphene electrode material through biomass carbon sources. The method mainly includes the steps that biomass such as eggshells of artemia cysts, bean pulp and shrimp shells are used as the carbon sources, red phosphorus or boric acid is added to serve as a stripping agent, metal nickel salt is added to serve as a catalyst, and oxygen-nitrogen-phosphor multi-atom co-doping three-dimensional porous graphene is synthesized in a roasted mode at the temperature of 700 DEG C to 900 DEG C under argon atmosphere; the obtained graphene is ground into powder, the graphene, acetylene black and PTFE are ultrasonically dispersed into absolute ethyl alcohol in the mass ratio of 85:10:5, the mixture is dried at the temperature of 80 DEG C to be pasty, 0.5 mg to 5 mg of the mixture is taken and evenly smeared on 1*1-cm foam nickel, vacuum drying is carried out at the temperature of 120 DEG C for 12 h, plate pressing is carried out at the pressure of 12 MPa, and an electrode plate is obtained. According to the method, the source of the required raw materials is wide, the price is low, devices are simple, repeatability is good, and low-cost large-scale industrial production can be achieved easily; the prepared graphene electrode material has the advantages of being good in electrochemical activity, large in specific area, not prone to repeated accumulation and the like; the broad application prospects are achieved in the aspects such as electrode materials and catalyst carriers of supercapacitors and lithium ion batteries.