Patent classifications
C01B32/162
DEVICE FOR PRODUCING CARBON NANOTUBE FIBERS AND METHOD FOR PRODUCING CARBON NANOTUBE FIBERS USING SAME
The present invention relates to an apparatus for producing a carbon nanotube fiber. The apparatus includes: a vertical reactor having a reaction zone; a concentric double-pipe inlet tube disposed on top of the reaction zone and consisting of an inner pipe through which a spinning feedstock including a spinning solution and a first gas is introduced into the reaction zone and an outer pipe defining a concentric annular portion surrounding the inner pipe and through which a second gas is introduced into the reaction zone; heating means for heating the reaction zone; and a discharge unit disposed under the bottom of the reaction zone to discharge a carbon nanotube fiber therethrough. The spinning feedstock entering the reaction zone through the inner pipe of the inlet tube is carbonized and graphitized while flowing from the top to the bottom of the reaction zone to form a carbon nanotube fiber consisting of a continuous sock (or aggregates) of carbon nanotubes. The second gas entering the reaction zone through the outer pipe of the inlet tube forms a gas curtain surrounding the circumference of the continuous sock of carbon nanotubes while flowing from the top to the bottom of the reaction zone. The gas curtain minimizes the contamination of the inner wall of the reactor and facilitates the discharge of the carbon nanotube fiber. Therefore, the apparatus of the present invention is suitable for the production of a carbon nanotube fiber in a continuous manner.
Carbon oxide reduction with intermetallic and carbide catalysts
A method of reducing a gaseous carbon oxide includes reacting a carbon oxide with a gaseous reducing agent in the presence of an intermetallic or carbide catalyst. The reaction proceeds under conditions adapted to produce solid carbon of various allotropes and morphologies, the selective formation of which can be controlled by means of controlling reaction gas composition and reaction conditions including temperature and pressure. A method for utilizing an intermetallic or carbide catalyst in a reactor includes placing the catalyst in a suitable reactor and flowing reaction gases comprising a carbon oxide with at least one gaseous reducing agent through the reactor where, in the presence of the catalyst, at least a portion of the carbon in the carbon oxide is converted to solid carbon and a tail gas mixture containing water vapor.
STRUCTURE FOR HOLDING CATALYST PARTICLES FOR CARBON NANOTUBE PRODUCTION AND METHOD FOR PRODUCING SAME
There are provided an easily producible catalyst particle-holding structure used for production of carbon nanotubes, and a method for producing the same. The method for producing the catalyst particle-holding structure of the present invention used for production of carbon nanotubes includes a step of forming a catalyst particle forming layer containing Si, Al, and Fe, and a step of performing a heat treatment on the catalyst particle forming layer in an atmosphere containing oxygen, to form catalyst particles containing Fe. The catalyst particles are held by the catalyst particle forming layer so that the catalyst particles are partially embedded in the catalyst particle forming layer. The size and the number of the catalyst particles containing Fe are controlled by adjusting the amount of oxygen contained in the atmosphere for the heat treatment. Thus, the catalyst particle-holding structure is formed easily.
INTERWOVEN CARBON NANOTUBE MATS
Systems and methods are provided for stitching together sheets of interwoven carbon nanotubes. One embodiment is a method that includes providing multiple sheets of interwoven carbon nanotubes, arranging the sheets over a substrate such that interstices of the sheets overlap at a stitch region of the substrate and heating catalysts at the substrate above a threshold temperature to trigger growth of new carbon nanotubes. The method also includes adjusting alignment of an electrical field that defines a direction of growth of the new carbon nanotubes, thereby causing the new carbon nanotubes to grow through the interstices and then stitch the sheets together.
Process for synthesizing carbon nanotubes on multiple supports
The present invention relates to a process for synthesizing carbon nanotubes by continuous chemical vapor deposition at the surface of reinforcements, said reinforcements constituting a mixture A (i) of particles and/or fibers of a material comprising at least one oxygen atom and (ii) of particles and/or fibers of a material chosen from carbides and/or of a material comprising at least one silicon atom, said process comprising the following steps, carried out under a stream of inert gas(es) optionally as a mixture with hydrogen: (i) heating of said mixture of reinforcements A in a reaction chamber at a temperature ranging from 400° C. to 900° C.; (ii) introducing into said chamber a source of carbon consisting of acetylene and/or xylene, and a catalyst comprising ferrocene; (iii) exposing said heated mixture A to the source of carbon and to the catalyst comprising ferrocene for a sufficient time to obtain carbon nanotubes at the surface of the reinforcements constituting said mixture A; (iv) recovering a mixture B at the end of step (iii), optionally after a cooling step, said mixture B consisting of the mixture (A) of reinforcements comprising carbon nanotubes at their surface; (v) optionally, separation (a) of the particles and/or fibers of a material comprising at least one oxygen atom, (b) of the particles and/or fibers of a material chosen from carbides and/or of a material comprising at least one silicon atom.
Carbon-Carbon Nanotube Hybrid Materials and Methods of Producing Same
Carbon-carbon nanotube (CNT) hybrid materials, and methods of producing the hybrid materials. The hybrid materials include carbon particles and CNTs on the surface of the particles. The CNT comprises more than about 3.2 weight percent of the hybrid material.
Carbon-Carbon Nanotube Hybrid Materials and Methods of Producing Same
Carbon-carbon nanotube (CNT) hybrid materials, and methods of producing the hybrid materials. The hybrid materials include carbon particles and CNTs on the surface of the particles. The CNT comprises more than about 3.2 weight percent of the hybrid material.
ULTRA-HIGH DENSITY SINGLE-WALLED CARBON NANOTUBE HORIZONTAL ARRAY AND ITS CONTROLLABLE PREPARATION METHOD
The present invention discloses single-walled carbon nanotubes horizontal arrays with ultra-high density and the preparation method. The method comprises the following steps: loading a catalyst on a single crystal growth substrate; after annealing, introducing hydrogen into a chemical vapor deposition system to conduct a reduction reaction of the catalyst; and maintaining the introduction of the hydrogen to conduct the orientated growth of a single-walled carbon nanotube. The density of the ultra-high density single-walled carbon nanotube horizontal array obtained by this method exceeds 130 tubes/micrometer, and an electrical performance test is performed on the prepared ultra-high density single-walled carbon nanotube horizontal array shows a high on-current density of 380 μA/μm, and the transconductance of 102.5 μS/μm.
Process for producing carbon nanotube composition and carbon nanotube composition
A method of the present invention for producing a carbon nanotube includes: a dispersing step of dispersing a carbon nanotube in a solvent by carrying out a dispersion treatment that brings about a cavitation effect, the carbon nanotube having an average diameter (Av) and a diameter distribution (3σ) that satisfy 0.60>3σ/Av>0.20; and a mixing step of mixing carbon nanotube slurry obtained in the dispersing step with latex.
SYSTEM AND METHOD FOR SURFACE TREATMENT AND BARRIER COATING OF FIBERS FOR IN SITU CNT GROWTH
A system for synthesizing carbon nanotubes (CNT) on a fiber material includes a surface treatment system adapted to modify the surface of the fiber material to receive a barrier coating upon which carbon nanotubes are to be grown, a barrier coating application system downstream of the surface treatment system adapted to apply the barrier coating to the treated fiber material surface, and a barrier coating curing system downstream of the barrier coating application systems for partially curing the applied barrier coating to enhance reception of CNT growth catalyst nanoparticles.