195results about "Multi-walled nanotubes" patented technology

The invention discloses a method for purifying a carbon nano tube by using a deep eutectic solvent. The method comprises the following steps: drying carbon nanotube powder prepared on a supported catalyst by adopting a chemical vapor deposition method; the method comprises the following steps: mixing a hydrogen bond donor and a hydrogen bond acceptor according to a fixed molar ratio, and stirring at a set temperature to obtain a homogeneous eutectic solvent; adding the dried carbon nanotube powder into a deep-eutectic solvent, and dissolving the supported catalyst particles by regulating and controlling the temperature and the time; and carrying out vacuum filtration, cleaning and drying treatment on the reacted liquid to obtain the high-quality carbon nanotube. Compared with a traditional strong acid purification process, the method has the advantages of being simple, environmentally friendly, low in cost and the like, the intrinsic structure and surface characteristics of the carbon nanotubes can be effectively kept, and the method has important industrial application prospects.

A field emission assembly and an electromagnetic wave generator are provided, the field emission assembly includes a linear emitter which includes carbon nanotube (CNT) fibers and emits electrons and a holder configured to fix the emitter, both ends of the emitter are fixed to the holder, and the emitter includes at least one of a curved portion so as to form a peak in an electron emission direction and a bent portion so as to form a peak in the electron emission direction.

The invention discloses a high-magnification ferric sodium pyrophosphate composite material as well as a preparation method and application thereof, and belongs to the technical field of sodium ion battery positive electrode materials. According to the positive electrode material, phosphoric acid and ferric pyrophosphate sodium nano-microspheres grow on multi-walled carbon nanotubes (MCNTs), so that the MCNTs are coated with the phosphoric acid and ferric pyrophosphate sodium nano-microspheres, and a composite material composed of a matrix MCNTS and a phosphoric acid and ferric pyrophosphate sodium microsphere coating layer is formed. The chemical formula of the material is Na4Fe3 (PO4) P2O7 (at) MCNTS. The ultrahigh-rate ferric sodium phosphate pyrophosphate composite material comprises an MCNTS carrier and a coating layer coated on the surface of the MCNTS. According to the pyrophosphate and ferric phosphate sodium nanosphere coated multi-walled carbon nanotube composite material provided by the invention, due to a cross-linked three-dimensional network structure, a sodion deintercalation path is greatly shortened, electrons are transferred among nanospheres at an ultra-fast speed, and aggregation of the nanospheres is also inhibited. Due to ultrahigh electronic and ionic conductivity, the nanospheres show remarkable high capacity, ultrahigh rate capability and super-long cycle performance.

The invention provides a porphyrin functionalized carbon nanotube compound. Medium-tetra (4-carboxyphenyl) porphyrin is covalently connected to the surface of an aminated carbon nanotube through an amido bond to form the compound. Stable amido bond connection is formed through amino-carboxyl condensation, and the bond energy is obviously higher than that of an ester bond. The invention also provides a preparation method of the porphyrin functionalized carbon nanotube compound, which comprises the following steps: carrying out carboxyl activation treatment on the meso-tetra (4-carboxyl phenyl) porphyrin by adopting a catalytic system consisting of N, N '-dicyclohexylcarbodiimide and N-hydroxysuccinimide; the preparation method comprises the following steps: performing ultrasonic treatment on aminated carbon nanotubes in N, N-dimethylformamide, adding the aminated carbon nanotubes into an activated meso-tetra (4-carboxyphenyl) porphyrin solution prepared in the step 1, performing stirring reaction at room temperature, and performing suction filtration and freeze drying to obtain a target product, namely the porphyrin functionalized carbon nanotube compound. A mild room-temperature stirring process is adopted, so that the dependence of a solvothermal method on high-temperature and high-pressure equipment is completely avoided, and the production cost is remarkably reduced.

The invention relates to the field of positive electrode materials, in particular to a carbon-coated lithium iron phosphate positive electrode material and a preparation method thereof, which are used for solving the core pain points that the lithium iron phosphate positive electrode material is low in electronic conductivity, slow in ion diffusion and easy to agglomerate particles in circulation. The carbon-coated lithium iron phosphate positive electrode material comprises a phosphorus-doped modified carbon nanotube, N-methyl pyrrolidone and lithium iron phosphate powder, the preparation method comprises the following steps: firstly, modifying a carbon nano tube by using a carbon nano tube modifier, then carrying out phosphorus doping to obtain a phosphorus-doped modified carbon nano tube, and then carrying out carbon coating treatment on lithium iron phosphate by using the phosphorus-doped modified carbon nano tube, the electron and ion transmission efficiency is remarkably improved, the high-rate discharge performance is optimized, the cycle stability is enhanced, and volume expansion and side reaction are inhibited.

A carbon nanotube assembled wire includes a plurality of carbon nanotubes, wherein the plurality of carbon nanotubes include a plurality of nitrogen-doped single-walled carbon nanotubes, a content ratio of nitrogen in the carbon nanotube assembled wire is 0.5 atomic % or more and 6 atomic % or less, and a content ratio of graphitic nitrogen in the carbon nanotube assembled wire is 0.4 atomic % or more and 3.5 atomic % or less.

A method for preparing carbon nanotubes according to an embodiment of the present invention comprises the steps of: injecting a carbon source, a metal catalyst, a co-catalyst, and a carrier gas into a reactor; and heating the reactor to prepare the carbon nanotubes. The ratio of the molar flow rate of the carbon source to the molar flow rate of the metal catalyst is 350 to 1300.

To provide a manufacturing method of a conductive material slurry which facilitates pre-dispersion by reducing a particle size of a conductive material by introduction of a dry process, produces a high-concentration dispersion, and has excellent dispersion characteristics by introduction of a post-process, as compared with a conventional manufacturing method of a conductive material slurry.SOLUTION: A method of preparing a conductive material dispersed slurry includes: dry-grinding a conductive material; pre-dispersing the conductive material by mixing the conductive material with a solvent and a dispersant; main-dispersing the pre-dispersed conductive material; and post-dispersing the main-dispersed mixture.SELECTED DRAWING: Figure 1

The invention provides a carbon nanotube purification method, which comprises: carrying out densification treatment on a carbon nanotube, and purifying the densified carbon nanotube at a temperature of 800-1400 DEG C by using ammonium chloride to obtain a purified carbon nanotube. According to the purification method provided by the invention, purification is carried out under the sub-high temperature condition of 800-1400 DEG C, the purification purity of the carbon nanotubes is high, and the content of metal impurities is low; pre-oxidation heat treatment is not needed, and the phenomenon that the structure of the carbon nano tube is damaged by high-temperature heat treatment at the temperature of 1700 DEG C or above is avoided; meanwhile, the purification efficiency is improved, and industrial amplification of the whole purification method is facilitated.

The present invention relates to a method for processing a sample using a glow discharge plasma, comprising one or more processing steps, wherein the sample for processing is subjected to plasma processing in a processing vessel equipped with a temperature control system, and during the one or more processing steps, the processing vessel is rotated about an axis to agitate the sample, and the temperature control system is used to cool or heat the sample. The present invention also relates to an apparatus for use in such a method.

The present invention relates to an iron-free supported catalyst for the selective conversion of hydrocarbons to carbon nanotubes, said catalyst comprising cobalt and vanadium as active catalytic metals in any oxidation state on a catalyst support comprising aluminum oxide hydroxide, wherein the mass ratio of cobalt to vanadium is between 2 and 15, and the mass ratio of cobalt to aluminum is between 5.8 and 10. -2 ~5.8 10 -1 and - the mass ratio of vanadium to aluminum is 5.8 10 -3 ~8.7 10 -2 The present invention also relates to a method for producing said iron-free supported catalyst and a method for producing carbon nanotubes using said iron-free supported catalyst.

Carbon nanotube (CNT) hybrid materials and methods for manufacturing such materials. The carbon nanotube (CNT) hybrid powder material comprises a CNT network in which particles of a second material are densely dispersed. In one example, the material comprises a blend of particles of a catalyst supported on a metal oxide and particles of a second material, and a CNT network grown on the supported catalyst within the blend. The CNT network is effective for dispersing the particles of the second material.

Provided are a multiwalled carbon nanotube assembly having high conductivity and good dispersibility in a dispersion medium, a multiwalled carbon nanotube dispersion liquid, a conductive material, an electrode, a secondary battery, a planar assembly, a filter, an electromagnetic shield, and an extreme ultraviolet protective film. A multi-walled carbon nanotube assembly, a multi-walled carbon nanotube dispersion, a conductive material, an electrode, a secondary battery, a planar assembly, a filter, an electromagnetic shield, and an extreme ultraviolet protective film, wherein the multi-walled carbon nanotube assembly contains Fe atoms and multi-walled carbon nanotubes having a maximum length of 1000-30000 [mu] m, and the Fe atom content ratio relative to the total mass of the assembly is 0.5 mass% or more but less than 10 mass%. The invention also provides a multi-walled carbon nanotube dispersion, a conductive material, an electrode, a secondary battery, a planar assembly, a filter, an electromagnetic shield, and an extreme ultraviolet protective film.

Part for a timepiece movement, made of a composite material comprising a rigid matrix and a forest of nanotubes contained in the rigid matrix.

The application provides an in-situ oriented carbon nanotube / silicon nitride nanobelt composite material and a preparation method thereof, and comprises the following steps: uniformly mixing methyltrimethoxysilane, dimethyldimethoxysilane, ethanol, water and nitric acid according to a certain proportion, and obtaining a siloxane xerogel precursor after stirring and drying; obtaining a silicon nitride nanomaterial by a carbothermal reduction reaction method under high-temperature conditions; injecting a mixed solution of ethanol, ethylenediamine and ferrocene into a tube furnace by a floating CVD method under high-temperature conditions, and growing carbon nanotubes on the surface of the silicon nitride nanobelt to obtain the in-situ oriented carbon nanotube / silicon nitride nanobelt composite material; and the application grows the carbon nanotubes on the surface of the silicon nitride nanobelt material by the floating CVD method to improve the electromagnetic shielding performance of the silicon nitride nanocomposite material, and finally, the carbon nanotube / silicon nitride nanobelt composite material with light weight, flexibility and good electromagnetic shielding performance is prepared.

The present invention relates to an improved catalyst for MWCNT production. The present invention also relates to an iron-free supported catalyst for the selective conversion of hydrocarbons into carbon nanotubes, said catalyst comprising cobalt and vanadium as active catalytic metals in any oxidation state on a catalyst support comprising hydroxyl alumina, wherein: - the mass ratio of cobalt to vanadium is between 2 and 15; - the mass ratio of cobalt to aluminum is between 5.8 x 10 ‑2 and 5.8 x 10 ‑1 ; and - the mass ratio of vanadium to aluminum is between 5.8 x 10 ‑3 and 8.7 x 10 ‑2 . The present invention also relates to a method for the preparation of said iron-free supported catalyst and to a method for the preparation of carbon nanotubes using said iron-free supported catalyst.

A carbon nanotube dispersion liquid includes carbon nanotubes (10) with an average fiber length of 10 µm or more, an aqueous solvent, and a dispersant (20) that is soluble in the aqueous solvent and has a weight-average molecular weight of 600000 or more. A content of the dispersant (20) is 10 parts by mass or more and 500 parts by mass or less relative to 100 parts by mass of the carbon nanotubes (10).

The present invention relates to a method for mass synthesis of carbon nanotubes and carbon nanotubes synthesized thereby and, more specifically, to a method for mass synthesis of carbon nanotubes and carbon nanotubes synthesized thereby, wherein the method enables not only the synthesis of a catalyst at a high rate through plasma generation without a separate reductant but also the continuous mass synthesis of high-purity carbon nanotubes. The technical essences of the present invention are a method for mass synthesis of carbon nanotubes and carbon nanotubes synthesized thereby, the method comprising: a first step of supplying a CNT growth material containing a carbon precursor; a second step of disposing a pair of metal wires in a solution mixed with a metal salt, and applying electric power to the metal wires to generate plasma; and a third step of thermally treating the CNT growth material and the catalyst.

The disclosure provides a flexible electrode material, a flexible electrode, and their preparation methods and applications, belonging to the technical field of composite materials. The carbon microparticle composite material includes carbon particles and gallium oxide attached to the surface of the carbon microparticles. The flexible electrode material includes, by mass, 2-17 parts of gallium-coated carbon particles and 83-98 parts of liquid metal. The flexible electrode is prepared by coating the flexible electrode material onto a flexible substrate via screen printing, attaching copper conductive wires to both ends of the printed flexible electrode material, applying a viscoelastic material coating over the surface of the flexible electrode material, and curing and drying the flexible electrode material at room temperature. The composite material can be applied to electronic skin for detecting human body motion states and earth pressure cells for monitoring soil pressure in engineering projects.

The invention provides a method and device system for continuously producing carbon nanotubes, and the method comprises the following steps: (1) carrying out high-temperature gasification on a metal raw material in a protective gas atmosphere to obtain a metal steam mixture; (2) the metal steam mixture obtained in the step (1) is subjected to rapid quenching through an annular air knife, and metal nanoparticles or metal liquid drops are obtained; (3) mixing a carbon precursor, an accelerant, reducing gas and the metal nano-particles or the metal liquid drops obtained in the step (2) to react, and separating to obtain the carbon nano-tubes; wherein the temperature of high-temperature gasification in the step (1) is greater than or equal to 2200 DEG C; the cooling rate of the rapid quenching in the step (2) is greater than or equal to 1 * 10 < 4 > DEG C / s. The industrial mass production of the carbon nanotubes is realized, the yield and quality of the carbon nanotubes are considered, the carbon source conversion rate is increased, the number of layers of the carbon nanotube walls is accurately controlled, retention and blockage of side reaction products are avoided, the reaction continuity is improved, and large-scale popularization and application are facilitated.

In the present disclosure, a carbon nanotube capable of forming an electrode film having further improved safety and good conductivity, a method for purifying the same, a carbon nanotube dispersion containing the carbon nanotube, a binder composition, a composition for electrodes, and a secondary battery are provided.

One embodiment of the present disclosure provides a catalyst for manufacturing carbon nanotubes, including a metal component represented by the following Chemical Formula 1:         [Chemical Formula 1]     Cox:[M1, Zr]y:M2z wherein Co represents cobalt or oxides or derivatives thereof, M1 represents at least one metal, or oxides or derivatives thereof, selected from Al, Ca, Si, Ti, and Mg, Zr represents zirconium, or oxides or derivatives thereof, M2 represents at least one metal, or oxides or derivatives thereof, selected from W, V, Mn, and Mo, x / y satisfies 0.2 ≤ x / y ≤ 2.6, and x / z satisfies 6 ≤ x / z ≤ 13.

A high-performance lithium battery current collector and a conductive slurry, and preparation methods therefor. A functional coating of the current collector is a functional layered covering structure with a thickness of no more than 800 nm formed by coating a conductive slurry on a surface of a metal foil and drying. The functional coating includes a plurality of strip-shaped modified conductive agents, and after being cured and molded, the modified conductive agents are parallel to one another in the functional coating, axes of the modified conductive agents are arranged obliquely relative to a surface of the metal foil at an included angle of 15° to 45° within a thickness of the functional coating, and the modified conductive agents are interwoven with a modified nanofiber, a binder and the conductive agent in the coating.

The invention discloses a graphene / carbon nanotube composite frequency selection film and a preparation method and application thereof, and particularly relates to the field of electromagnetic protection materials. Mixing a carbon nanotube material, a surfactant, a binder and a solvent to obtain carbon nanotube slurry; preparing a carbon nanotube film by using the carbon nanotube slurry; depositing and growing a graphene film on the surface of the carbon nanotube film to obtain a graphene / carbon nanotube composite film; and etching patterns on the graphene / carbon nanotube composite film to obtain the composite frequency selection film. The carbon nanotubes are combined into a mutually lapped three-dimensional skeleton structure, an initial network channel is provided for electron transmission, and the surfaces of the carbon nanotubes are coated with graphene through a chemical vapor deposition process, so that the electron transmission capability at the lapping sites of the carbon nanotubes is further enhanced, and the conductivity of the composite frequency selection film is improved.

The disclosure relates to modified multi-walled carbon nanotubes (MWCNTs) that include MWCNTs with carboxylate moieties (e.g., laurate moieties) covalently bonded thereto, and related methods.

Methods for producing a conductive element precursor and a conductive element, such as a tape or wire, are provided. The methods comprise growing a plurality of carbon nanotubes on a metallic substrate and coating carbon nanotubes of the plurality of carbon nanotubes on the metallic substrate with a metallic material.

Carbon-based composite materials are provided, such as those comprising at least 80 weight % of graphitic carbon comprising functional groups capable of forming hydrogen bonds, the graphitic carbon in the form of a mat of randomly entangled elongated structures; not more than 20 weight % of a polymer or a nanofiber thereof, dispersed within the graphitic carbon, the polymer or the nanofiber thereof comprising corresponding functional groups capable of forming hydrogen bonds with the functional groups of the graphitic carbon; and a plurality of hydrogen bonds at an interface formed between the graphitic carbon and the polymer or the nanofiber thereof, the plurality of hydrogen bonds formed between the functional groups of the graphitic carbon and the corresponding functional groups of the polymer or the nanofiber thereof.

A catalyst, catalyst precursor, and carbon nanotubes grown using the catalyst. The catalyst includes a support comprising alumina and a cobalt species on a surface of the support, wherein cobalt is the sole active catalyst species for carbon nanotube growth. The support surface is iron-free.

A carbon nanotube dispersion solution, a slurry for manufacturing an electrode containing carbon nanotubes, and a secondary battery fabricated using the same are provided. The performance of a secondary battery comprising carbon nanotubes can be improved by controlling the particle size and amount of the carbon nanotubes.

A multifunctional end cap catalyst is provided, comprising a multi-wall carbon nanotube with a multi-metal catalyst at the end cap. The catalyst contributes preferentially to growing a multi-wall carbon nanotube through a methane pyrolysis process at a lower temperature, and then infuses the nanotube into a host material, such as concrete, asphalt, polymer, or steel, improving functional parameters including thermal conductivity, electrical conductivity, wettability, flexural strength, tensile strength, or interfacial bonding strength. The catalyst can also increase the host material's decrease phonon scattering or interfacial resistance, and lower the final defect density of the multi-wall carbon nanotube. The multifunctional end cap catalyst can be composed of various metals, including copper, nickel, and manganese, and can achieve specific functional states, such as oxidized or functionalized metal states, without increasing the final defect density.