326 results about "Graphitic carbon" patented technology

A method for multi-dimensional chromatography of a polyolefin polymer, comprising introducing a solution of the polyolefin polymer into a liquid flowing through a first liquid chromatography stationary phase or a field flow fractionation device and subsequently flowing the solution through a second liquid chromatography stationary phase, the second liquid chromatography stationary phase comprising graphitic carbon, the polyolefin polymer emerging from the liquid chromatography stationary phase with a retention factor greater than zero.

Composites comprising at least one graphite-carbon nanofiber (GCNF) and a polymer phase covalently linked to a surface thereof.

This disclosure relates to a porous electrically conductive carbon material having interconnected pores in first and second size ranges from 10[mu]m to 100nm and from less than 100nm to 3nm and a graphene structure and to diverse uses of the material such as an electrode in a lithium-ion battery and a catalyst support, e.g. for the oxidation of methanol in a fuel cell. The carbon material has been heat treated to effect conversion to non-graphitic carbon with the required degree of order at a temperature in the range from 600 DEG C to 1000 DEG C. A lithium-ion battery and an electrode for a lithium-ion battery are also claimed.

The non-aqueous secondary battery of the present invention includes a positive electrode, a negative electrode, a non-aqueous electrolyte, and a separator, the negative electrode contains a negative electrode active material containing a graphitic carbon material and a composite in which a carbon coating layer is formed on a surface of a core material containing Si and O as constituent elements, the composite has a carbon content of 10 to 30 mass %, the composite has an intensity ratio I₅₁₀/I₁₃₄₃ of a peak intensity I₅₁₀ at 510 cm⁻¹ derived from Si to a peak intensity I₁₃₄₃ at 1343 cm⁻¹ derived from carbon of 0.25 or less when a Raman spectrum of the composite is measured at a laser wavelength of 532 nm, and the half-width of the (111) diffraction peak of Si is less than 3.0° when the crystallite size of an Si phase contained in the core material is measured by X-ray diffractometry using CuKα radiation.

The invention discloses a lithium ion battery cathode material and a preparation method thereof, which lower the cost of the lithium ion battery cathode material and improve the high-energy density thereof. The lithium ion battery cathode material takes more than one of natural crystalline graphite, natural cryptocrystalline graphite and natural crystalline vein graphite as matrixes, a non-graphitic carbon material is coated outside the matrixes, and the coated particles are compounded with a conductive material. The preparation method of the lithium ion battery cathode material comprises the following steps of mixing and drying a liquid phase, carbonizing, carrying out high-temperature treatment and compounding. Compared with the prior art, the graphite with lower carbon content is taken as a raw material to greatly reduce the raw material cost; by adopting a hot air drying mode, the preparation process is simplified and a coating layer is more solid and compact; and by adopting lower carburizing temperature and the temperature for high-temperature heat treatment, energy consumption is reduced, and product cost is further lowered.

Composite silicon based materials are described that are effective active materials for lithium ion batteries. The composite materials comprise processed, e.g., high energy mechanically milled, silicon suboxide and graphitic carbon in which at least a portion of the graphitic carbon is exfoliated into graphene sheets. The composite materials have a relatively large surface area, a high specific capacity against lithium, and good cycling with lithium metal oxide cathode materials. The composite materials can be effectively formed with a two step high energy mechanical milling process. In the first milling process, silicon suboxide can be milled to form processed silicon suboxide, which may or may not exhibit crystalline silicon x-ray diffraction. In the second milling step, the processed silicon suboxide is milled with graphitic carbon. Composite materials with a high specific capacity and good cycling can be obtained in particular with balancing of the processing conditions.

A method for improving the wear characteristics of ID bushings comprising the steps of providing an ID bushing comprising electro-graphitic carbon.

The invention belongs to the technical field of a nanomaterial, and specifically relates to an iron-nitrogen-doped graphene porous material with dual-site catalytic oxygen reduction activity, and a preparation method and an application therefor. The porous material is formed by embedding graphite-carbon-coated iron carbide into a nitrogen-doped porous graphene band network structure; the preparation method for the iron-nitrogen-doped graphene porous material comprises the steps of preparing a graphene oxide solution; adding a proper amount of conductive macromolecular pyrrole to the graphene oxide solution; obtaining uniform hydrogel through a hydrothermal process; performing oxidative polymerization on the hydrogel by ferric iron; then dispersing the hydrogel into a fresh ferric iron solution to complete adsorption; then performing drying and high-temperature carbonization thermal processing; and finally removing non-active and free iron phase from the reaction system by dilute acid so as to obtain the iron-nitrogen-doped graphene porous material. The porous material can be used as the negative electrode catalyst for a fuel cell, and shows quite high catalytic oxygen reduction activity, so that the porous material has quite important research meaning and bright application prospects.

An alkaline cell having an anode comprising zinc, an aqueous alkaline electrolyte, a cathode mixture comprising cathode active material comprising copper oxide or copper hydroxide. Graphitic carbon, preferably expanded graphite or graphitic carbon nanofibers are added to the cathode mixture thereby resulting in a sharp drop in cathode resistivity. The cathode active material preferably comprises between about 80 and 92 percent by weight of the cathode. The sharp drop in cathode resistivity resulting from the addition of expanded graphite or graphitic carbon nanofibers makes the cell suitable for use as a primary alkaline cell having good capacity. The graphitic carbon, preferably graphitic nanofibers comprise preferably between about 4 and 10 percent by weight of the cathode. The carbon nanofibers have an average diameter desirably less than 500 nanometers, preferably between about 50 and 300 nanometers.

Disclosed are non-noble element compositions of matter, structures, and methods for producing the catalysts that can catalyze oxygen reduction reactions (ORR). The disclosed composition of matter can be comprised of graphitic carbon doped with nitrogen and associated with one or two kinds of transition metals. The disclosed structure is a three dimensional, porous structure comprised of a plurality of the disclosed compositions of matter. The disclosed structure can be fashioned into an electrode of an electrochemical cell to serve as a diffusion layer and also to catalyze an ORR. Two methods are disclosed for producing the disclosed composition of matter and structure. The first method is comprised of two steps, and the second method is comprised of a single step.

A magnetic media for magnetic data recording having a plurality of magnetic grains protected by thin layers of graphitic carbon. The layers of graphitic carbon are formed in a manner similar to onion skins on an onion and can be constructed as single monatomic layers of carbon. The thin layers of graphitic carbon can be formed as layers of graphene or as fullerenes that either cover or partially encapsulate the magnetic gains. The layers of graphitic carbon provide excellent protection against corrosion and wear and greatly reduce magnetic spacing for improved magnetic performance.

A production of high-purity graphitic carbon material and its apparatus are disclosed. The process involves raw material system, roasting system and post-treating system: 1) breaking forged petroleum coke by raw material system with grain size up to 0-60 mm and controlling water content <=5%; 2) delivering the treated material into vertical roasting electric furnace and high-temperature treating, preheating, purifying and graphitizing under high-temperature, controlling temperature at 1800-3000deg.C, cooling and discharging at 50-250deg.C with 6-21 hrs; and 3) breaking and screening discharged material by post-treating system with grain size up to 0-50 mm, classifying and packing. The vertical roasting electric furnace consists of upper and lower electrode, supporting frame, material disc, the third cooling section, electrode cooling cover, furnace core carbon fireproof material, furnace casing, furnace lid , smoke conduit, and bucket.

The invention discloses a high-energy high-power density lithium ion supercapacitor and an assembling method thereof and belongs to the technical field of electrochemical energy storage devices. In order to greatly improve the energy density of the lithium ion supercapacitor, non-graphitic carbon materials with a certain oxygen-containing functional groups are used as positive and negative electrodes, after the electrodes are embedded in advance, a lithium salt organic electrolyte solution is used as an electrolyte solution, and the lithium ion supercapacitor is assembled. According to the design and assembling mode, the positive and negative electrodes can be always positioned in the most suitable potential interval in the operating process of a device, and the characteristics of high specific capacity and high power of the non-graphitic carbon materials are exerted to the greatest degree. Moreover, an available voltage window of the electrolyte can be fully utilized, so that the operating voltage of the device reaches an upper limit of decomposition voltage of the electrolyte, and the energy density and power density of the lithium ion supercapacitor are greatly improved.

The invention discloses a lithium vanadate anode material, an anode, a battery and an anode material preparation method, and belongs to the field of batteries. The lithium vanadate anode material is of a core-shell structure, the core is lithium vanadate, the shell is a coating layer, lithium vanadate is nanometer granules or micrometer level secondary granules formed by nanometer granules, the thickness of the coating layer is 2-30nm, and the coating layer comprises a conductive coating layer or/and a stable coating layer. An organic carbon source is introduced into a high temperature reactor with an inert gas as a carrier by using a chemical vapor deposition method, in order to from the conductive coating layer of amorphous carbon or graphitic carbon on the surface of the core. The conductive coating layer and the stable coating layer are prepared by using a vacuum coating method, a magnetron sputtering method, a pulsed laser deposition method or an atomic layer deposition method. Lithium vanadate is used as an active anode material to obtain high coulombic efficiency, large specific capacity and good rate capability, and the proper embedded escape potential and the considerable volume of lithium vanadate are fully utilized.

Electrically conductive polymer composite materials comprised of: a) an effective amount of substantially crystalline graphitic carbon nanofibers comprised of graphite sheets that are substantially parallel to the longitudinal axis of the nanofiber, preferably wherein said grip sheets form a multifaceted tubular structure; and b) a polymeric component.

The present invention relates to a process for preparing a porous graphite carbon with high crystallinity, which comprises the steps of: (a) hydrothermally treating sucrose (i.e. carbon precursor), transitional metal precursor and uniform-sized silica particles at the same time to prepare a polymer; and (b) carbonizing the polymer, which can provide a porous graphite carbon with remarkably improved crystallinity suitable for a catalyst support for a fuel cell.

A method and apparatus are disclosed wherein a battery comprises at least one electrode formed from a graphitic carbon nanostructured surface wherein the nanostructured surface consists of a plurality of nanoposts formed from graphitic carbon such that the graphitic nanoposts serve both as an operational feature (i.e., dielectric/electrode) and control feature of the battery itself. In one embodiment, the nanostructured surface consists of a plurality of nanoposts wherein a select portion of each nanopost is formed to serve as the dielectric of the nanostructured battery, and the balance of each nanopost is utilized to impart the control features to the nanostructured battery.

The invention relates to graphitic carbon, in particular to a non-hard template method for preparing a graphite composite material with large specific surface area by taking a PPy/biomass complex as a carbonization precursor and quickly carbonizing and graphitizing the carbonization precursor under the action of microwave. The concrete preparation method comprises the steps: firstly, adopting ferric trichloride as a catalyst, and adopting steam phase polymerization technology to prepare a Fe/PPy/biomass complex; then performing micro-wave carbonization treatment on the prepared Fe/PPy/biomass complex; and finally removing generated ferric carbide from a sample through acid treatment to obtain a graphitized carbon material with high specific surface area. With similar methods, the applicant also successfully prepares a metallic carbide/graphitized carbon composite material.

This invention discloses one carbon materials generating film and its process method, which makes use of one micro carbon powder, conductive carbon powder excellent electricity and thermal property and adds proper stabilizer, adhesive agent and disperser to make flexible electricity film materials. Comparing with current technique, the invention product is of high conversion efficiency and good saving effect and can product low temperature, middle temperature type with highest temperature of 350 degrees and its voltage is between 3.6V to 650V with wide utility range and with simple process.

Embodiments described herein provide methods and apparatus for forming graphitic carbon such as graphene on a substrate. The method includes providing a precursor comprising a linear conjugated hydrocarbon, depositing a hydrocarbon layer from the precursor on the substrate, and forming graphene from the hydrocarbon layer by applying energy to the substrate. The precursor may include template molecules such as polynuclear aromatics, and may be deposited on the substrate by spinning on, by spraying, by flowing, by dipping, or by condensing. The energy may be applied as radiant energy, thermal energy, or plasma energy.

The invention provides a method for preparing a spherical aluminum nitride powder. The method comprises the following steps of: 1, mixing aluminum powder with aluminum nitride powder and ammonium chloride powder, putting the mixture into a mortar for grinding, wherein the aluminum powder is spherical aluminum powder having the particle size range from 0.5 micron to 3 microns; and the aluminum nitride powder is prepared from an aluminum source which is spherical aluminum powder having the same particle size with the raw material aluminum powder through in-situ nitrogenation; 2, putting the evenly ground powder in a porous graphite crucible with a graphitic carbon felt exterior heat preservation layer and an interior protective layer and reacting in a reaction device; 3, electrifying graphite paper, and igniting the powder from bottom to cause a combustion reaction; 4, after natural cooling, releasing nitrogen in the reaction chamber, and opening the reaction device, and obtaining an off-white powder in the porous graphite crucible, namely the spherical aluminum nitride powder; and 5, controlling the particle size of the spherical aluminum nitride powder through the particle size of the spherical aluminum powder. The method provided by the invention has the characteristics of low energy consumption, simple process and low cost; and the prepared spherical aluminum nitride powder is good in homogeneity and controllable in particle size.

A heat dissipative composite material including a carbon fiber lay-up having a resin pyrolized to form a graphitic carbon laminate structure. A structural resin fills voids in the graphitic carbon laminate structure and provides strength to the graphitic carbon laminate structure.