US20050002850A1 - Methods of oxidizing multiwalled carbon nanotubes - Google Patents

Methods of oxidizing multiwalled carbon nanotubes Download PDF

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US20050002850A1
US20050002850A1 US10/857,470 US85747004A US2005002850A1 US 20050002850 A1 US20050002850 A1 US 20050002850A1 US 85747004 A US85747004 A US 85747004A US 2005002850 A1 US2005002850 A1 US 2005002850A1
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nanotubes
carbon nanotubes
oxidized
gas
oxidizing agent
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Chunming Niu
David Moy
Asif Chishti
Robert Hoch
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Hyperion Catalysis International Inc
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Hyperion Catalysis International Inc
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Priority to US10/857,470 priority Critical patent/US20050002850A1/en
Publication of US20050002850A1 publication Critical patent/US20050002850A1/en
Priority to US11/271,422 priority patent/US7413723B2/en
Priority to US11/841,449 priority patent/US8580436B2/en
Priority to US14/075,005 priority patent/US20140162040A1/en
Abandoned legal-status Critical Current

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Definitions

  • the invention relates broadly to methods of oxidizing the surface of multiwalled carbon nanotubes.
  • the invention also encompasses methods of making aggregates of surface-oxidized nanotubes, and using the same.
  • the invention also relates to complex structures comprised of such surface-oxidized carbon nanotubes linked to one another.
  • This invention lies in the field of submicron graphitic carbon fibrils, sometimes called vapor grown carbon fibers or nanotubes.
  • Carbon fibrils are vermicular carbon deposits having diameters less than 1.0 ⁇ , preferably less than 0.5 ⁇ , and even more preferably less than 0.2 ⁇ . They exist in a variety of forms and have been prepared through the catalytic decomposition of various carbon-containing gases at metal surfaces. Such vermicular carbon deposits have been observed almost since the advent of electron microscopy. (Baker and Harris, Chemistry and Physics of Carbon, Walker and Thrower ed., Vol. 14, 1978, p. 83; Rodriguez, N., J. Mater. Research, Vol. 8, p. 3233 (1993)).
  • the Tennent invention provided access to smaller diameter fibrils, typically 35 to 700 ⁇ (0.0035 to 0.070 ⁇ ) and to an ordered, “as grown” graphitic surface. Fibrillar carbons of less perfect structure, but also without a pyrolytic carbon outer layer have also been grown.
  • the carbon nanotubes which can be oxidized as taught in this application, are distinguishable from commercially available continuous carbon fibers.
  • carbon fibrils In contrast to these fibers which have aspect ratios (L/D) of at least 10 4 and often 10 6 or more, carbon fibrils have desirably large, but unavoidably finite, aspect ratios.
  • the diameter of continuous fibers is also far larger than that of fibrils, being always >1.0 ⁇ and typically 5 to 7 ⁇ .
  • the carbon planes of the graphitic nanotube take on a herring bone appearance.
  • fishbone fibrils These are termed fishbone fibrils.
  • These carbon nanotubes are also useful in the practice of the invention.
  • Carbon nanotubes of a morphology similar to the catalytically grown fibrils described above have been grown in a high temperature carbon arc (Iijima, Nature 354, 56, 1991). It is now generally accepted (Weaver, Science 265, 1994) that these arc-grown nanofibers have the same morphology as the earlier catalytically grown fibrils of Tennent. Arc grown carbon nanofibers after colloquially referred to as “bucky tubes”, are also useful in the invention.
  • Carbon nanotubes differ physically and chemically from continuous carbon fibers which are commercially available as reinforcement materials, and from other forms of carbon such as standard graphite and carbon black.
  • Standard graphite because of its structure, can undergo oxidation to almost complete saturation.
  • carbon black is amorphous carbon generally in the form of spheroidal particles having a graphene structure, carbon layers around a disordered nucleus. The differences make graphite and carbon black poor predictors of nanotube chemistry.
  • carbon nanotubes may be in the form of discrete nanotubes, aggregates of nanotubes or both.
  • Nanotubes are prepared as aggregates having various morphologies (as determined by scanning electron microscopy) in which they are randomly entangled with each other to form entangled balls of nanotubes resembling bird nests (“BN”); or as aggregates consisting of bundles of straight to slightly bent or kinked carbon nanotubes having substantially the same relative orientation, and having the appearance of combed yarn (“CY”) e.g., the longitudinal axis of each nanotube (despite individual bends or kinks) extends in the same direction as that of the surrounding nanotubes in the bundles; or, as, aggregates consisting of straight to slightly bent or kinked nanotubes which are loosely entangled with each other to form an “open net” (“ON”) structure.
  • open net structures the extent of nanotube entanglement is greater than observed in the combed yarn aggregates (in which the individual nanotubes have substantially the same relative orientation) but less than that of bird nest.
  • the morphology of the aggregate is controlled by the choice of catalyst support.
  • Spherical supports grow nanotubes in all directions leading to the formation of bird nest aggregates.
  • Combed yarn and open nest aggregates are prepared using supports having one or more readily cleavable planar surfaces, e.g., an iron or iron-containing metal catalyst particle deposited on a support material having one or more readily cleavable surfaces and a surface area of at least 1 square meters per gram.
  • Moy et al. U.S. application Ser. No. 08/469,430 entitled “Improved Methods and Catalysts for the Manufacture of Carbon Fibrils”, filed Jun. 6, 1995, hereby incorporated by reference, describes nanotubes prepared as aggregates having various morphologies (as determined by scanning electron microscopy).
  • Nanotube mats or assemblages have been prepared by dispersing nanofibers in aqueous or organic mediums and then filtering the nanofibers to form a mat or assemblage.
  • the mats have also been prepared by forming a gel or paste of nanotubes in a fluid, e.g. an organic solvent such as propane and then heating the gel or paste to a temperature above the critical temperature of the medium, removing the supercritical fluid and finally removing the resultant porous mat or plug from the vessel in which the process has been carried out.
  • a fluid e.g. an organic solvent such as propane
  • Fibrils have also been oxidized non-uniformly by treatment with nitric acid.
  • International Application PCT/US94/10168 filed on Sep. 9, 1994 as WO95/07316. discloses the formation of oxidized fibrils containing a mixture of functional groups.
  • Hoogenvaad, M. S., et al. (“Metal Catalysts supported on a Novel Carbon Support”, Presented at Sixth International Conference on Scientific Basis for the Preparation of Heterogeneous Catalysts, Brussels, Belgium, September 1994) also found it beneficial in the preparation of fibril-supported precious metals to first oxidize the fibril surface with nitric acid.
  • Such pretreatment with acid is a standard step in the preparation of carbon-supported noble metal catalysts, where, given the usual sources of such carbon, it serves as much to clean the surface of undesirable materials as to functionalize it.
  • U.S. Pat. No. 5,641,466 to Ebbesen et al. describes a procedure for purifying a mixture of arc grown arbon nanotubes and impurity carbon materials such as carbon nanoparticles and possibly amorphous carbon by heating the mixture in the presence of an oxidizing agent at a temperature in the range of 600° C. to 1000° C. until the impurity carbon materials are oxidized and dissipated into gas phase.
  • nanotube surfaces have been generally discussed in U.S. Ser. No. 08/352,400 filed on Dec. 8, 1994 and in U.S. Ser. No. 08/856,657 filed May 15, 1997, both incorporated herein by reference.
  • the nanotube surfaces are first oxidized by reaction with strong oxidizing or other environmentally unfriendly chemical agents.
  • the nanotube surfaces may be further modified by reaction with other functional groups.
  • the nanotube surfaces have been modified with a spectrum of functional groups so that the nanotubes could be chemically reacted or physically bonded to chemical groups in a variety of substrates.
  • Representative functionalized nanotubes broadly have the formula [C n H L —]R m
  • the carbon atoms, C n are surface carbons of the nanofiber.
  • Oxidation permits interaction of the oxidized nanotubes with various substrates to form unique compositions of matter with unique properties and permits structures of carbon nanotubes to be created based on linkages between the functional sites on the surfaces of the carbon nanotubes.
  • the present invention which addresses the needs of the prior art provides methods of oxidizing multiwalled carbon nanotubes having a diameter no greater than 1 micron.
  • multiwalled nanotubes can be oxidized by contacting them with a gas-phase oxidizing agent at defined temperatures and pressures.
  • the gas-phase oxidizing agents of the invention include CO 2 , O 2 , steam, N 2 O, NO, NO 2 , O 3 , ClO 2 and mixtures thereof. Near critical and supercritical water can also be used as oxidizing agents.
  • the oxidized multiwalled carbon nanotubes prepared according to methods of the invention include carbon and oxygen containing moieties, such as carbonyl, carboxyl, aldehyde, ketone, hydroxy, phenolic, esters, lactones and derivatives thereof.
  • the multiwalled carbon nanotubes oxidized according to methods of the present invention can be subjected to a secondary treatment step whereby the oxygen containing moieties of the oxidized nanotubes react with suitable reactants to add at least a secondary group onto the surface of the oxidized nanotubes.
  • multiwalled carbon nanotubes oxidized according to methods of the invention are provided which are also useful in preparing a network of carbon nanotubes, a rigid porous structure or as starting material for electrodes utilized in electrochemical capacitors.
  • Electrochemical capacitors assembled from electrodes made from the oxidized multiwalled carbon nanotubes of the invention exhibit enhanced electrochemical characteristics, such as specific capacitance.
  • FIG. 1 is a schematic illustration of a quartz reactor used to carry out gas phase oxidation.
  • FIG. 2 is an SEM micrograph illustrating aggregates of multiwalled carbon nanotubes oxidized according to the invention at ⁇ 3000 magnification.
  • FIG. 3 is an SEM micrograph illustrating aggregates of multiwalled carbon nanotubes oxidized according to the invention at ⁇ 50,000 magnification.
  • FIG. 4 is an SEM micrograph illustrating aggregates of multiwalled carbon nanotubes oxidized according to the invention at ⁇ 10,000 magnification.
  • FIG. 5 is an SEM micrograph illustrating the tip portion of an aggregate of multiwalled carbon nanotubes oxidized according to the invention at ⁇ 50,000 magnification.
  • FIGS. 6A to 6 C are each a complex-plane impedance plot, a Bode impedance plot, and a Bode angle plot, respectively, recorded from an electrochemical capacitor fabricated from electrodes prepared from multiwalled carbon nanotubes oxidized according to methods of the invention.
  • nanotube refers to an elongated hollow structure having a cross section (e.g. angular fibers having edges) or a diameter (e.g. rounded) less than 1 micron.
  • nanotube also includes “buckytubes”, and fishbone fibrils.
  • Multiwalled nanotubes refers to carbon nanotubes which are substantially cylindrical, graphitic nanotubes of substantially constant diameter and comprise cylindrical graphitic sheets or layers whose c-axes are substantially perpendicular to their cylindrical axis, as also described in U.S. Pat. No. 5,171,560 to Tennent, et al..
  • the term “functional group” refers to groups of atoms that give the compound or substance to which they are linked characteristic chemical and physical properties.
  • a “functionalized” surface refers to a carbon surface on which chemical groups are adsorbed or chemically attached.
  • Graphenic carbon is a form of carbon whose carbon atoms are each linked to three other carbon atoms in an essentially planar layer forming hexagonal fused rings.
  • the layers are platelets only a few rings in diameter or they may be ribbons, many rings long but only a few rings wide.
  • Graphenic analogue refers to a structure which is incorporated in a graphenic surface.
  • Graphitic carbon consists of grapheric layers which are essentially parallel to one another and no more than 3.6 angstroms apart.
  • aggregate refers to a dense, microscopic particulate structure comprising entangled carbon nanotubes.
  • micropore refers to a pore which has a diameter of less than 2 nanometers.
  • pores refers to pores having a cross section greater than 2 nanometers and less than 50 nanometers.
  • surface area refers to the total surface area of a substance measurable by the BET technique.
  • accessible surface area refers to that surface area not attributed to micropores (i.e., pores having diameters or cross-sections less than 2 ram).
  • isotropic means that all measurements of a physical property within a plane or volume of the structure, independent of the direction of the measurement, are of a constant value. It is understood that measurements of such non-solid compositions must be taken on a representative sample of the structure so that the average value of the void spaces is taken into account.
  • physical property means an inherent, measurable property, e.g., surface area, resistivity, fluid flow characteristics, density, porosity, and the like.
  • substantially means that ninety-five percent of the values of the physical property when measured along an axis of, or within a plane of or within a volume of the structure, as the case may be, will be within plus or minus ten percent of a mean value.
  • substantially isotropic or “relatively isotropic” correspond to the ranges of variability in the values of physical properties set forth above.
  • the present invention provides methods of oxidizing the surface of carbon nanotubes.
  • the resulting oxidized nanotubes can be easily dispersed in both organic and inorganic solvents, and especially in water.
  • the surface-oxidized nanotubes obtained by the methods of the present invention can be placed in matrices of other materials, such as plastics, or made into structures useful in catalysis, chromatography, filtration systems, electrodes, capacitors and the like.
  • Carbon Nanotubes useful for the methods of the present invention have been more specifically described above under the heading “Carbon Nanotubes,” and they are preferably prepared according to U.S. application Ser. No. 08/459,534 filed Jun. 2, 1995 assigned to Hyperion Catalysis International, Inc. of Cambridge, Mass., incorporated herein by reference.
  • the carbon nanotubes preferably have diameters no greater than one micron, more preferably no greater than 0.2 micron. Even more preferred are carbon nanotubes having diameters between 2 and 100 nanometers, inclusive. Most preferred are carbon nanotubes having diameters between 3.5 and 75 nanometers, inclusive.
  • the nanotubes are substantially cylindrical, graphitic carbon fibrils of substantially constant diameter and are substantially free of pyrolytically deposited carbon.
  • the nanotubes include those having a length to diameter ratio of greater than 5 with the projection of the graphite layers on the nanotubes extending for a distance of at least two nanotube diameters.
  • Most preferred are multiwalled nanotubes as described in U.S. Pat. No. 5,171,560 to Tennent, et al, incorporated herein by reference.
  • the methods of the invention include contacting the carbon nanotubes with a gas-phase oxidizing agent under conditions sufficient to oxidize the surface of the carbon nanotubes, and especially the external side walls of the carbon nanotubes.
  • gas-phase oxidizing agents are commercially readily available and include carbon dioxide, oxygen, steam, N 2 O, NO, NO 2 , ozone, ClO 2 and mixtures thereof
  • gas-phase oxidizing agents can be diluted with inert gases such as nitrogen, noble gases and mixtures thereof. The dilution reduces the partial pressure of the oxidant to the range of 1 to 760 torr.
  • Suitable conditions for oxidizing the carbon nanotubes of the invention include a temperature range from about 200° C. to about 600° C. whenever the oxidizing agent is oxygen, ozone, N 2 O, NO, NO 2 , ClO 2 or mixtures thereof.
  • the mass molecular weight of the oxidizing agents of the present invention does not exceed 70 g/mole.
  • the treatment of the carbon nanotubes with the gas-phase oxidizing agent is preferably accomplished in a temperature range from about 400° C. to about 900° C.
  • Useful partial pressures of the oxidizing agent for the methods of the present invention include contacting of the carbon nanotubes with the gas-phase oxidizing agents of the invention in a range from about 1 torr to about 10 atm or 7600 torr, preferably 5 torr to 760 torr.
  • the gas-phase oxidizing agent is near critical or supercritical water.
  • Supercritical water refers to water above its critical temperature of 374° C. At this temperature, retention of a condensed phase requires a pressure in excess of 3200 psia. It is well known that supercritical water exhibits anomalously low viscosity, thus enabling it to penetrate aggregates.
  • Viscosities useful in practicing the invention can also be achieved in near critical water having a specific volume up to twice its critical specific volume of 0.05 ft3/lb or up to 0.10 ft3/lb. While this range of specific volumes can be achieved by various combinations of near critical temperature and pressure, at saturation, this corresponds to a temperature of 363° C. and a pressure of 3800 psia.
  • a useful period of time for contacting of the carbon nanotubes or aggregates of carbon nanotubes, with the gas-phase oxidizing agents of the invention is from 0.1 hours to about 24 hours, preferably from about 1 hour to about 8 hours, and most preferably for about 24 hours.
  • the present invention provides economical, environmentally benign methods to oxidize the surface of the multiwalled carbon nanotubes. While not wishing to be bound by theory, it is believed that when treating the carbon nanotubes with the oxidizing agents of the invention oxygen-containing moieties are introduced onto the surface side walls of the carbon nanotubes.
  • the oxidized nanotubes include moieties such as carbonyl, carboxyl, aldehyde, phenol, hydroxy, esters, lactones and mixtures thereof. Specifically excluded are moieties in which oxygen is not directly bonded to carbon. For example, the use of SO 3 vapor results in the sulfonation of the carbon nanotubes whereby sulfur containing moieties are introduced onto the surface of the nanotubes. Sulfonated nanotubes exhibit a significant weight gain by comparison to non-sulfonated carbon nanotubes.
  • the oxidized nanotubes have experienced a weight loss rather than gain.
  • the carbon nanotubes experienced a weight loss from about 1% to about 60% by weight and preferably from about 2% to about 15% by weight by comparison to the unoxidized carbon nanotubes.
  • the edge carbon of a graphite sheet is much more susceptible to chemical reaction than the basal plane carbon.
  • the carbon nanotubes useful in the present invention have a tubular structure resembling buckytubes. On the surface along the axis, the carbon atoms have the characteristics of basal plane graphite except for those associated with defect sites.
  • the carbon atoms at the end of a nanotube are either edge carbons or carbons associated with high-energy bonds, like members of a five-carbon ring or atoms attached to a catalyst particles. All of these carbons are much more susceptible to chemical attack.
  • the nanotubes may become shortened and surface carbon layers may be partially stripped.
  • the oxidized nanotubes produced by the methods of the invention exhibit upon titration an acid titer of from about 0.05 meq/g to about 0.6 meq/g and preferably from about 0.1 meq/g to about 0.4 meq/g.
  • the content of carboxylic acid is determined by reacting an amount of 0.1 N NaOH in excess of the anticipated titer with the sample and then back titrating the resulting slurry with 0.1N HCl to an end point determined potentiometrically at pH7.
  • Another aspect of the invention relates to treating aggregates of carbon nanotubes with the gas-phase oxidizing agents.
  • the aggregates treated according to the invention display a macromorphology which can be described as “loose bundles” having the appearance of a severely weathered rope.
  • the nanotubes themselves retain a morphology similar to the as-synthesized nanotubes, however, with oxygen-containing moieties attached to the nanotube surfaces. While it is not intended to be bound by theory, it is believed that in the case of aggregates, the chemical bonding between the catalyst plate which defines the size of the bundles and the nanotubes is eliminated. In addition, the nanotubes may exhibit shortening and carbon layers are believed to become partially stripped. An increase in specific surface area has also been observed.
  • untreated aggregates have a specific surface area of about 250 m 2 /gm, while oxidized aggregates display a specific surface area up to 400 m 2 /gm.
  • SEM scanning electron microscopy
  • TEM transmission electron microscopy
  • FIGS. 2-5 taken after treatment of aggregates with the oxidizing agents of the invention support the structured changes of the nanotubes discussed above.
  • FIGS. 3 and 5 show many shortened and separated nanotube ends which can be seen at the ends of and on the surface of the “loose bundles” of oxidized nanotube aggregates. More importantly, FIGS.
  • Gas phase oxidized nanotubes can also be used in the production of high quality extrudates which can be formed by using a small amount of water soluble binder.
  • the oxidized surface of the nanotubes allows for improved binder dispersion during the mixing stage and minimizes the segregation of binder in the subsequent heating step.
  • the oxidized nanotubes obtained by the oxidizing methods of the invention can be further treated.
  • they may be further treated in a secondary treatment step, by contacting with a reactant suitable to react with moieties of the oxidized nanotubes thereby adding at least another secondary functional group.
  • Secondary derivatives of the oxidized nanotubes are essentially limitless.
  • oxidized nanotubes bearing acidic groups like —COOH are convertible by conventional organic reactions to virtually any desired secondary group, thereby providing a wide range of surface hydrophilicity or hydrophobicity.
  • the secondary group that can be added by reacting with the moieties of the oxidized nanotubes include but are not limited to alkyl/aralkyl groups having from 1 to 18 carbons, a hydroxyl group having from 1 to 18 carbons, an amine group having from 1 to 18 carbons, alkyl aryl silanes having from 1 to 18 carbons and fluorocarbons having from 1 to 18 carbons.
  • Other appropriate secondary groups that can be attached to the moieties present on the oxidized nanotubes include a protein, a peptide, an enzyme, an antibody, a nucleotide peptide, an oligonucleotide, an antigen or an enzyme substrate, enzyme inhibitor or the transition state analog of an enzyme substrate.
  • the invention is also in methods for producing a network of carbon nanotubes comprising treating carbon nanotubes with a gas phase oxidizing agent of the invention for a period of time sufficient to oxidize the surface of the carbon nanotubes, contacting the oxidized carbon nanotubes with a reactant suitable for adding a secondary functional group to the surface of the carbon nanotube, and further contacting the secondarily treated nanotubes with a cross-linking agent effective for producing a network of carbon nanotubes.
  • a preferred cross-linking agent is a polyol, polyamine or polycarboxylic acid.
  • a useful polyol is a diol and a useful polyamine is a diamine.
  • a network of carbon nanotubes is obtained by first oxidizing the as-produced carbon nanotubes with the gas-phase oxidizing agents of the invention, followed by subjecting the oxidized nanotubes to conditions which foster crosslinking. For example, heating the oxidized nanotubes in a temperature range from 180° C. to 450° C. resulted in crosslinking the oxidized nanotubes together with elimination of the oxygen containing moieties of the oxidized nanotubes.
  • the invention also includes three-dimensional networks formed by linking the surface-modified nanotubes of the invention.
  • These complexes include at least two surface-modified nanotubes linked by one or more linkers comprising a direct bond or chemical moiety.
  • These networks comprise porous media of remarkably uniform equivalent pore size. They are useful as adsorbents, catalyst supports and separation media.
  • the oxidized nanotubes of the invention are more easily dispersed in aqueous media than unoxidized nanotubes.
  • Stable, porous 3-dimensional structures with meso- and macropores (pores>2 nm) are very useful as catalysts or chromatography supports. Since nanotubes can be dispersed on an individualized basis, a well-dispersed sample which is stabilized by cross-links allows one to construct such a support.
  • Surface-oxidized nanotubes are ideal for this application since they are easily dispersed in aqueous or polar media and the oxygen-containing moieties present on the oxidized nanotubes provide cross-link points. Additionally, the oxygen-containing moieties also provide points to support the catalytic or chromatographic sites. The end result is a rigid, 3-dimensional structure with its total surface area accessible with secondary group sites on which to support the active agent.
  • interstices between these nanotubes are irregular in both size and shape, they can be thought of as pores and characterized by the methods used to characterize porous media.
  • the size of the interstices in such networks can be controlled by the concentration and level of dispersion of nanotubes, and the concentration and chain lengths of the cross-linking agents.
  • Such materials can act as structured catalyst supports and may be tailored to exclude or include molecules of a certain size. Aside from conventional industrial catalysis, they have special applications as large pore supports for biocatalysts.
  • Typical applications for these supports in catalysis include their use as a highly porous support for metal catalysts laid down by impregnation, e.g., precious metal hydrogenation catalysts.
  • the ability to anchor molecular catalysts by tether to the support via the secondary groups combined with the very high porosity of the structure allows one to carry out homogeneous reactions in a heterogeneous manner.
  • the tethered molecular catalyst is essentially dangling in a continuous liquid phase, similar to a homogeneous reactor, in which it can make use of the advantages in selectivities and rates that go along with homogeneous reactions.
  • being tethered to the solid support allows easy separation and recovery of the active, and in many cases, very expensive catalyst.
  • the rigid networks can also serve as the backbone in biomimetic systems for molecular recognition. Such systems have been described in U.S. Pat. No. 5,110,833 and International Patent Publication No. WO93/19844.
  • the appropriate choices for cross-linkers and complexing agents allow for stabilization of specific molecular frameworks.
  • rigid porous structures are prepared by first preparing surface-oxidized nanotubes as described above, dispersing them in a medium to form a suspension, separating the medium from the suspension to form a porous structure, wherein the surface-oxidized nanotubes are further interconnected to form a rigid porous structure, all in accordance with methods more particularly described in U.S. application Ser. No. 08/857,383 (WBAM Docket No. 0064734-0080) entitled “Rigid Porous Carbon Structures, Methods of Making, Methods of Using and Products Containing Same” filed on May 15, 1997, hereby incorporated by reference.
  • the hard, high porosity structures can be formed from regular carbon nanotubes or nanotube aggregates, either with or without surface modified nanofibers (i.e., surface oxidized nanofibers).
  • surface modified nanofibers i.e., surface oxidized nanofibers.
  • polymer at the intersections of the structure This may be achieved by infiltrating the assemblage with a dilute solution of low molecular weight polymer cement kie., less than about 1,000 MW) and allowing the solvent to evaporate. Capillary forces will concentrate the polymer at nanotube intersections. It is understood that in order to substantially improve the stiffness and integrity of the structure, only a small fraction of the nanotube intersections need be cemented.
  • One embodiment of the invention relates to a method of preparing a rigid porous carbon structure having a surface area greater than at least 100 m 2 /gm, comprising the steps of:
  • the nanotubes may be uniformly and evenly distributed throughout the structure or in the form of aggregate particles interconnected to form the structure.
  • the nanotubes are dispersed thoroughly in the medium to form a dispersion of individual nanotubes.
  • nanotube aggregates are dispersed in the medium to form a slurry and said aggregate particles are connected together with a gluing agent to form said structure.
  • the medium used may be selected from the group consisting of water and organic solvents.
  • the medium comprises a dispersant selected from the group consisting of alcohols, glycerin, surfactants, polyethylene glycol, polyethylene imines and polypropylene glycol.
  • the medium should be selected which: (1) allows for fine dispersion of the gluing agent in the aggregates; and (2) also acts as a templating agent to keep the internal structure of the aggregates from collapsing as the mix dries down.
  • One preferred embodiment employs a combination of polyethylene glycol (PEG) and glycerol dissolved in water or alcohol as the dispersing medium, and a carbonizable material such as low MW phenol-formaldehyde resins or other carbonizable polymers or carbohydrates (starch or sugar).
  • PEG polyethylene glycol
  • glycerol dissolved in water or alcohol
  • carbonizable material such as low MW phenol-formaldehyde resins or other carbonizable polymers or carbohydrates (starch or sugar).
  • the nanotubes are oxidized prior to dispersing in the medium and are self-adhering forming the rigid structure by binding at the nanotube intersections.
  • the structure may be subsequently pyrolized to remove oxygen.
  • a useful temperature range is from about 200° C. to about 2000° C. and preferably from about 200° C. to about 900° C.
  • the nanotubes are dispersed in said suspension with gluing agents and the gluing agents bond said nanotubes to form said rigid structure.
  • the gluing agent comprises carbon, even more preferably the gluing agent is selected from a material that, when pyrolized, leaves only carbon. Accordingly, the structure formed with such a gluing may be subsequently pyrolized to convert the gluing agent to carbon.
  • the gluing agents are selected from the group consisting of cellulose, carbohydrates, polyethylene, polystyrene, nylon, polyurethane, polyester, polyamides and phenolic resins.
  • the step of separating comprises filtering the suspension or evaporating the medium from said suspension.
  • the suspension is a gel or paste comprising the nanotubes in a fluid and the separating comprises the steps of:
  • Isotropic slurry dispersions of nanotube aggregates in solvent/dispersant mixtures containing gluing agent can be accomplished using a Waring blender or a kneader without disrupting the aggregates.
  • the nanotube aggregates trap the resin particles and keep them distributed.
  • These mixtures can be used as is, or can be filtered to remove sufficient solvent to obtain cakes with high nanotube contents (5-20% dry weight basis).
  • the cake can be molded, extruded or pelletized.
  • the molded shapes are sufficiently stable so that further drying occurs without collapse of the form.
  • disperant molecules, along with particles of gluing agent are concentrated and will collect at nanotube crossing points both within the nanotube aggregates, and at the outer edges of the aggregates.
  • nanotube strands within the aggregates and the aggregates themselves are glued together at contact points. Since the aggregate structures do not collapse, a relatively hard, very porous, low density particle is formed.
  • the rigid, porous structures may also be formed using oxidized nanotubes with or without a gluing agent. Carbon nanotubes become self-adhering after oxidation. Very hard, dense mats are formed by highly dispersing the oxidized nanotubes (as individualized strands), filtering and drying. The dried mats have densities between 1-1.2 g/cc, depending on oxygen content, and are hard enough to be ground and sized by-sieving. Measured surface areas are about 275 m 2 /g.
  • Substantially all the oxygen within the resulting rigid structure can be removed by pyrolizing the particles at about 600° C. in flowing gas, for example argon. Densities decrease to about 0.7-0.9 g/cc and the surface areas increase to about 400 m 2 /g. Pore volumes for the calcined particles are about 0.9-0.6 cc/g, measured by water absorbtion.
  • the oxidized nanotubes may also be used in conjunction with a gluing agent.
  • Oxidized nanotubes are good starting materials since they have attachment points to stick both gluing agents and templating agents. The latter serve to retain the internal structure of the particles or mats as they dry, thus preserving the high porosity and low density of the original nanotube aggregates.
  • Good dispersions are obtained by slurrying oxidized nanotubes with materials such as polyethyleneimine cellulose (PEI Cell), where the basic imine functions form strong electrostatic interactions with carboxylic acid functionalized fibrils. The mix is filtered to form mats. Pyrolizing the mats at temperatures greater than 650° C. in an inert atmosphere converts the PEI Cell to carbon which acts to fuse the nanotube aggregates together into hard structures. The result is a rigid, substantially pure carbon structure, which can then be oxidized with the oxidizing agents of the present invention.
  • PEI Cell polyethyleneimine cellulose
  • Solid ingredients can also be incorporated within the structure by mixing the additives with the nanotube dispersion prior to formation of the structure.
  • the content of other solids in the dry structure may be made as high as fifty parts solids per part of nanotubes.
  • nanotubes are dispersed at high shear in a high-shear mixer, e.g. a Waring Blender.
  • the dispersion may contain broadly from 0.01 to 10% nanotubes in water, ethanol, mineral spirits, etc.. This procedure adequately opens nanotube bundles, i.e. tightly wound bundles of nanotubes, and disperses the nanotubes to form self-supporting mats after filtration and drying.
  • the application of high shear mixing may take up to several hours. Mats prepared by this method, however, are not free of aggregates.
  • dispersion is improved. Dilution to 0.1% or less aids ultrasonication.
  • 200 cc of 0.1% fibrils may be sonified by a Bronson Sonifier Probe (450 watt power supply) for 5 minutes or more to further improve the dispersion.
  • sonication must take place either at very low concentration in a compatible liquid, e.g. at 0.001% to 0.01% concentration in ethanol or at higher concentration e.g. 0.1% in water to which a surfactant, e.g. Triton X-100, has been added in a concentration of about 0.5%.
  • a surfactant e.g. Triton X-100
  • the mat which is subsequently formed may be rinsed free or substantially free of surfactant by sequential additions of water followed by vacuum filtration.
  • the mat thus formed can then be oxidized with the oxidizing agents of the invention under conditions sufficient to form oxidized nanotubes within the mat.
  • Particulate solids such as MnO 2 (for batteries) and Al 2 O 3 (for high temperature gaskets) may be added to the oxidized nanotube dispersion prior to mat formation at up to 50 parts added solids per part of nanotubes.
  • Reinforcing webs and scrims may be incorporated on or in the mats during formation.
  • Examples are polypropylene mesh and expanded nickel screen.
  • Carbon nanotubes are electrically conductive. Electrodes and their use in electrochemical capacitors comprising carbon nanotubes and/or functionalized carbon nanotubes which have been described in U.S. application Ser. No. 08/856,657 (WBAM Docket No. 0064736-0000) entitled “Graphitic Nanofibers in Electrochemical Capacitors,” filed on May 15, 1997 incorporated herein by reference.
  • the quality of sheet electrode depends on the microstructure of the electrode, the density of the electrode, the functionality of the electrode surface and mechanical integrity of the electrode structure.
  • microstructures of the electrode namely, pore size and size distribution determines the ionic resistance of electrolyte in the electrode.
  • the surface area residing in micropores (pore diameter ⁇ 2 nm) is considered inaccessible for the formation of a double layer (2).
  • distributed pore sizes, multiple-pore geometries (dead end pores, slit pores, cylindrical pores, etc.) and surface properties usually give rise to a distributed time constant.
  • the energy stored in an electrode with a distributed time constant can be accessed only with different rates. The rapid discharge needed for pulsed power is not feasible with such an electrode.
  • the density of the electrode determines its volumetric capacitance.
  • An electrode with density less than 0.4 g/cc is not practical for real devices. Simply, the low-density electrode will take up too much electrolyte, which will decrease both volumetric and gravimetric capacitance of the device.
  • the surface of the carbon nanotubes is related to the wetting properties of electrodes towards electrolytes.
  • the surface of as-produced, catalytically grown carbon nanotubes is hydrophobic. It has been unexpectedly found that the hydrophobic surface properties of the as-produced carbon nanotubes can be changed to hydrophilic by treatment of the as-produced carbon nanotubes or aggregates of carbon nanotubes with the oxidizing agents of the present invention. It has also been unexpectedly found that the dispersing properties in water of surface-oxidized carbon nanotubes are related to weight loss during treatment with such gas-phase oxidizing agents as CO 2 , O 2 , steam, H 2 O, NO 2 , O 3 , ClO 2 and mixtures thereof.
  • oxidized nanotubes exhibiting a weight loss of about 10% by weight can be easily dispersed in water. It is necessary to oxidize on the surface of the carbon nanotubes to improve their wetting properties for aqueous electrolytes. Furthermore, the capacitance can be increased by further attaching redox groups on the surface of the carbon nanotubes.
  • the structural integrity of the electrodes is critical to reproducibility and long term stability of the device.
  • Mechanical strength of electrodes incorporating carbon nanotubes is determined by the degree of entanglement of the carbon nanotube and bonding between carbon nanotubes in the electrode. A high degree of entanglement and carbon nanotube bonding can also improve the conductivity, which is critical to the power performance of an electrode.
  • the specific capacitance (D.C. capacitance) of the electrodes made from gas-phase treated fibrils was about 40 F/g.
  • One aspect of the present invention relates to preparing electrodes and electrochemical capacitors from surface-oxidized carbon nanotubes.
  • prepared carbon nanotubes have been treated with gas-phase oxidizing agents of the invention to provide surface oxidized, multiwalled carbon nanotubes which can be used to prepare the electrodes of the invention.
  • the oxidized nanotubes can be further treated with a reactant suitable to react with moieties present on the oxidized nanotubes to form nanotubes having secondary groups on its surface which are also useful in preparing the electrodes of the present invention.
  • Electrodes are assembled by simple filtration of slurries of the treated nanotubes. Thickness is controlled by the quantity of material used and the geometry, assuming the density has been anticipated based on experience. It may be necessary to adjust thickness to get self-supporting felts.
  • the electrodes are advantageously characterized by cyclic voltammetry, conductivity and DC capacitance measurement.
  • Oxidized carbon nanotubes were prepared by using CO 2 in the gaseous phase. About 10 grams of carbon nanotubes were placed into a reactor as shown in FIG. 1 .
  • the reactor was a heated quartz tube having a reacting chamber connected at each end to a side tube.
  • the reacting chamber had an outside diameter of about 3 inches and each side tube has an outside diameter of about 1 inch.
  • a stream of gaseous CO 2 was continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at about 800° C.
  • the degree of oxidation was measured by the weight loss exhibited by the carbon nanotubes; a weight loss of about 10% was recorded.
  • the carbon nanotubes oxidized in this manner dispersed in water quite easily whereas they hardly did so prior to treatment with gaseous CO 2 .
  • Carbon nanotubes were oxidized by using wet air. About 10 grams of carbon nanotubes prepared according to U.S. application Ser. No. 08/459,534 filed on Jun. 2, 1995 were charged into the reactor described in Example 1.
  • Air saturated with water vapor at room temperature was continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min.
  • the temperature of the reactor measured by a k-type thermocouple positioned inside the bed of carbon nanotubes, was set at 530° C.
  • the degree of oxidation was controlled by variation of the reaction duration and monitored by weight loss, compared to the initial weighted unoxidized carbon nanotubes. Three samples with weight losses of 7.1, 12.4, and 68% corresponding to 4, 5, and 8 hr oxidation, respectively, were prepared.
  • Carbon nanotubes are oxidized by using oxygen in the gas phase. About 10 grams of carbon nanotubes prepared according to U.S. Ser. No. 08/459,534 filed on Jun. 2, 1995 are charged into a reactor as described in Example 1.
  • a stream of gaseous oxygen is continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at 600° C.
  • the temperature of the reactor is measured by a k-type thermocouple positioned inside the bed of carbon nanotubes.
  • the degree of oxidation is controlled by variation of the reaction duration and monitored by weight loss as compared to the initial weight of unoxidized carbon nanotubes. The resulting weight loss is about 10%.
  • the carbon nanotubes oxidized in this manner disperse in water quite easily whereas they hardly do so prior to treatment with gaseous oxygen.
  • Carbon nanotubes are oxidized by using N 2 O in the gas phase. About 10 grams of carbon nanotubes prepared according to U.S. Ser. No.08/459,534 filed on Jun. 2, 1995 are charged into a reactor as described in Example 1.
  • a stream of gaseous N 2 O is continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at 600° C.
  • the temperature of the reactor is measured by a k-type thermocouple positioned inside the bed of carbon nanotubes.
  • the degree of oxidation is controlled by variation of the reaction duration and monitored by weight loss as compared to the initial weight of unoxidized carbon nanotubes. The resulting weight loss is about 10%.
  • the carbon nanotubes oxidized in this manner disperse in water quite easily whereas they hardly do so prior to treatment with gaseous N 2 O.
  • Carbon nanotubes are oxidized by using NO in the gas phase. About 10 grams of carbon nanotubes prepared according to U.S. Ser. No.08/459,534 filed on June 2, 1995 are charged into a reactor as described in Example 1.
  • a stream of gaseous NO is continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at 600° C.
  • the temperature of the reactor is measured by a k-type thermocouple positioned inside the bed of carbon nanotubes.
  • the degree of oxidation is controlled by variation of the reaction duration and monitored by weight loss as compared to the initial weight of unoxidized carbon nanotubes. The resulting weight loss is about 10%.
  • the carbon nanotubes oxidized in this manner disperse in water quite easily whereas they hardly do so prior to treatment with gaseous NO.
  • Carbon nanotubes are oxidized by using NO 2 in the gas phase. About 10 grams of carbon nanotubes prepared according to U.S. Ser. No.08/459,534 filed on June 2, 1995 are charged into a reactor as described in Example 1.
  • a stream of gaseous oxygen is continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at 600° C.
  • the temperature of the reactor is measured by a k-type thermocouple positioned inside the bed of carbon nanotubes.
  • the degree of oxidation is controlled by variation of the reaction duration and monitored by weight loss as compared to the initial weight of unoxidized carbon nanotubes. The resulting weight loss is about 10%.
  • the carbon nanotubes oxidized in this manner disperse in water quite easily whereas they hardly do so prior to treatment with gaseous NO 2 .
  • Carbon nanotubes are oxidized by using ozone in the gas phase. About 10 grams of carbon nanotubes prepared according to U.S. Ser. No.08/459,534 filed on June 2, 1995 are charged into a reactor as described in Example 1.
  • a stream of gaseous ozone is continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at 600° C.
  • the temperature of the reactor is measured by a k-type thermocouple positioned inside the bed of carbon nanotubes.
  • the degree of oxidation is controlled by variation of the reaction duration and monitored by weight loss as compared to the initial weight of unoxidized carbon nanotubes. The resulting weight loss is about 10%.
  • the carbon nanotubes oxidized in this manner disperse in water quite easily whereas they hardly do so prior to treatment with gaseous ozone.
  • Carbon nanotubes are oxidized by using ClO 2 in the gas phase. About 10 grams of carbon nanotubes prepared according to U.S. Ser. No.08/459,534 filed on Jun. 2, 1995 are charged into a reactor as described in Example 1.
  • a stream of gaseous ClO 2 is continuously passed down through the bed of carbon nanotubes at a rate of about 120 cc/min for 2 hours at 600° C.
  • the temperature of the reactor is measured by a k-type thermocouple positioned inside the bed of carbon nanotubes.
  • the degree of oxidation is controlled by variation of the reaction duration and monitored by weight loss as compared to the initial weight of unoxidized carbon nanotubes. The resulting weight loss is about 10%.
  • the carbon nanotubes oxidized in this manner disperse in water quite easily whereas they hardly do so prior to treatment with gaseous ClO 2 .
  • Electrochemical Capacitors Prepared From Carbon Nanotubes Oxidized With CO 2
  • 0.1 g of oxidized nanotubes as prepared in Example 1 were dispersed in deionized water to form a slurry which was then filtered on a 3.5′′ diameter filter membrane to form a mat with diameter of about 3.3′′.
  • the mat was dried at 120° C. for approximately one hour and heated at 350° C. in air for 4 hr. The final weight was 0.095 g.
  • the disk electrodes with diameter of 0.5′′ were made from the mat and soaked overnight in 38% sulfuiric acid held at approximately 85° C. and then kept in the acid solution at 25° C. until cell assembly. The electrodes were wetted easily by the electrolyte.
  • Single cell test devices were fabricated with two 38% sulfuric acid saturated electrodes separated by a 0.001′′ thick polymer separator which was also wetted with 38% sulfuric acid.
  • the equivalent series resistance (E.S.R.) of the test device measured at 1 kHz using a fixed frequency meter was 0.0430.
  • the capacitance of the device was measured by a constant current discharging method.
  • the calculated specific capacitance for the electrode was 40 F/g.
  • the frequency response analysis was carried out at d.c. biases of 0V, 0.5V and 1V with a 10 mV amplitude sinusoidal signal using a Solartron model 1250B frequency analyzer driving an EG&G PAR model 273 potensiostat/galvonostat.
  • Electrochemical Capacitors Prepared From Wet-air Oxidized Nanotubes
  • Nanotubes oxidized as in example 2 were prepared into an electrode according to the process described in example 3.
  • Three single-cell test electrochemical capacitors were fabricated from electrodes made from the nanotubes with weight losses of 7.1, 12.4, and 68%, respectively.
  • Table I summarizes properties of these electrodes and test results of the capacitors made from them.
  • the resistivity of the electrodes was measured using the van der Pauw method, on samples with dimensions of 0.5 cm ⁇ 0.5 cm having four leads attached to their comer edges. Ohmic contact of the leads to the samples was tested by measuring a linear I-V curve.
  • Cyclic voltammograms were recorded using an EG&G PAR Model 273 Potentiostat/Galvonostar connected to a three-electrode cell consisting of a fibril working electrode, a platinum gauze counter electrode and a standard Ag/AgC1 reference electrode.
  • the electrolyte was 38% sulfuric acid.
  • E.S.R. equivalent series resistance
  • Impedance analysis was carried out with a Solartron 11250 frequency response analyzer driving an EG&G PAR model 273 Potentiostat/Galvonostat at a dc bias of 0, 0,5 and 1V with 10 mV amplitude sinusoidal signal).
  • FIGS. 6 A-C show frequency response analysis result of the test device fabricated from sample 1 (Table I).
  • the electrodes functioned like a non-porous, planar electrode. This was evidenced (FIGS. 6 A,- 6 C) in the complex-plane impedance plots in which no clear “knee” point was present, and further in the Bode angle plot, up to 10 Hz, showing a near ⁇ 90° phase angle for an ideal capacitor.
  • the invention has application in the formulation of a wide variety of oxidized nanofibers.

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Cited By (40)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050127030A1 (en) * 2003-07-24 2005-06-16 Fuji Xerox Co., Ltd. Carbon nanotube structure, method of manufacturing the same, carbon nanotube transfer body, and liquid solution
US20060137718A1 (en) * 2004-12-29 2006-06-29 Industrial Technology Research Institute Method for removing impurities from porous materials
WO2006079005A2 (en) * 2005-01-21 2006-07-27 William Marsh Rice University Metal-free silicon-molecule-nanotube testbed and memory device
US20060223243A1 (en) * 2005-03-30 2006-10-05 Marko Radosavljevic Carbon nanotube - metal contact with low contact resistance
US20080036123A1 (en) * 2004-08-31 2008-02-14 Hyperion Catalysis International, Inc. Conductive thermosets by extrusion
US20090116170A1 (en) * 2007-11-02 2009-05-07 Tsinghua University Electrochemical capacitor with carbon nanotubes
US20090116171A1 (en) * 2007-11-02 2009-05-07 Tsinghua University Electrochemical capacitor with carbon nanotubes
US20090168302A1 (en) * 2007-12-29 2009-07-02 Tsinghua University Electrochemical capacitor with carbon nanotubes
US20090318043A1 (en) * 2006-03-06 2009-12-24 Nanoledge Inc. Method for making polymeric extruded composite products and carbon nanotubes
US20100240922A1 (en) * 2003-11-03 2010-09-23 The Research Foundation Of State University Of New York Sidewall-functionalized carbon nanotubes, and methods for making the same
US20100308279A1 (en) * 2005-09-16 2010-12-09 Chaohui Zhou Conductive Silicone and Methods for Preparing Same
US20110060087A1 (en) * 2008-04-16 2011-03-10 Nissin Kogyo Co., Ltd. Carbon nanofiber, method for production thereof, method for production of carbon fiber composite material using carbon nanofiber, and carbon fiber composite material
US20110141618A1 (en) * 2009-12-15 2011-06-16 Albert Wallash Use of Carbon Nanotubes to Form Conductive Gaskets Deployed in Sensitive Environments
US20130009109A1 (en) * 2003-09-08 2013-01-10 Nantero Inc. Spin-Coatable Liquid for Formation of High Purity Nanotube Films
US8679444B2 (en) 2009-04-17 2014-03-25 Seerstone Llc Method for producing solid carbon by reducing carbon oxides
US20140286852A1 (en) * 2013-03-19 2014-09-25 Nanolab, Inc. Synthesis of length-selected carbon nanotubes
US9090472B2 (en) 2012-04-16 2015-07-28 Seerstone Llc Methods for producing solid carbon by reducing carbon dioxide
US9221685B2 (en) 2012-04-16 2015-12-29 Seerstone Llc Methods of capturing and sequestering carbon
US9475699B2 (en) 2012-04-16 2016-10-25 Seerstone Llc. Methods for treating an offgas containing carbon oxides
US9586823B2 (en) 2013-03-15 2017-03-07 Seerstone Llc Systems for producing solid carbon by reducing carbon oxides
US9598286B2 (en) 2012-07-13 2017-03-21 Seerstone Llc Methods and systems for forming ammonia and solid carbon products
US9604848B2 (en) 2012-07-12 2017-03-28 Seerstone Llc Solid carbon products comprising carbon nanotubes and methods of forming same
US9650251B2 (en) 2012-11-29 2017-05-16 Seerstone Llc Reactors and methods for producing solid carbon materials
US9731970B2 (en) 2012-04-16 2017-08-15 Seerstone Llc Methods and systems for thermal energy recovery from production of solid carbon materials by reducing carbon oxides
US9779845B2 (en) 2012-07-18 2017-10-03 Seerstone Llc Primary voltaic sources including nanofiber Schottky barrier arrays and methods of forming same
US9783416B2 (en) 2013-03-15 2017-10-10 Seerstone Llc Methods of producing hydrogen and solid carbon
US9783421B2 (en) 2013-03-15 2017-10-10 Seerstone Llc Carbon oxide reduction with intermetallic and carbide catalysts
US9796591B2 (en) 2012-04-16 2017-10-24 Seerstone Llc Methods for reducing carbon oxides with non ferrous catalysts and forming solid carbon products
US9896341B2 (en) 2012-04-23 2018-02-20 Seerstone Llc Methods of forming carbon nanotubes having a bimodal size distribution
US10086349B2 (en) 2013-03-15 2018-10-02 Seerstone Llc Reactors, systems, and methods for forming solid products
US10115844B2 (en) 2013-03-15 2018-10-30 Seerstone Llc Electrodes comprising nanostructured carbon
US10133204B2 (en) * 2007-11-14 2018-11-20 Xerox Corporation Imaging device components comprised of hydrophobic carbon nanotubes
US10815124B2 (en) 2012-07-12 2020-10-27 Seerstone Llc Solid carbon products comprising carbon nanotubes and methods of forming same
US10910636B2 (en) 2018-01-23 2021-02-02 Tsinghua University Method for making battery electrodes
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US11053362B2 (en) * 2017-10-11 2021-07-06 Molecular Rebar Design, Llc Mixtures of discrete carbon nanotubes
CN113646263A (zh) * 2019-03-27 2021-11-12 国立大学法人大阪大学 碳同素异形体表面经改性的物质的制造方法、碳同素异形体表面导入有官能团的物质的制造方法、冷冻电子显微镜用栅格的制造方法、有机物质、冷冻电子显微镜用栅格
US11286163B2 (en) * 2018-07-12 2022-03-29 Tsinghua University Method for making carbon nanotube arrays
US11643328B2 (en) 2017-03-16 2023-05-09 Zeon Corporation Method of producing surface-treated carbon nanostructures
US11752459B2 (en) 2016-07-28 2023-09-12 Seerstone Llc Solid carbon products comprising compressed carbon nanotubes in a container and methods of forming same

Families Citing this family (94)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
ATE514804T1 (de) * 1999-07-21 2011-07-15 Hyperion Catalysis Int Verfahren zur oxidation von mehrwandigen kohlenstoffnanoröhren
US6689234B2 (en) 2000-11-09 2004-02-10 Bechtel Bwxt Idaho, Llc Method of producing metallic materials
ATE522909T1 (de) * 2001-10-29 2011-09-15 Hyperion Catalysis Int Polymer mit funktionalisierten kohlenstoff- nanoröhren
US7147894B2 (en) * 2002-03-25 2006-12-12 The University Of North Carolina At Chapel Hill Method for assembling nano objects
ATE363716T1 (de) 2002-06-14 2007-06-15 Hyperion Catalysis Int Elektroleitfähige farbstoffe und beschichtungen auf kohlenstofffibrilenbasis
FR2843382B1 (fr) * 2002-08-08 2005-12-23 Centre Nat Rech Scient Procede d'ouverture de nanotubes de carbone a leurs extremites et applications
CN1296994C (zh) * 2002-11-14 2007-01-24 清华大学 一种热界面材料及其制造方法
US20040150312A1 (en) * 2002-11-26 2004-08-05 Mcelrath Kenneth O. Carbon nanotube particulate electron emitters
JP2004193443A (ja) * 2002-12-13 2004-07-08 Honda Motor Co Ltd 電気二重層キャパシタ用電極
JP4379002B2 (ja) * 2003-05-30 2009-12-09 富士ゼロックス株式会社 カーボンナノチューブデバイスの製造方法、並びに、カーボンナノチューブ転写体
US7682654B2 (en) 2003-06-03 2010-03-23 Seldon Technologies, Llc Fused nanostructure material
JP2005045188A (ja) * 2003-07-25 2005-02-17 Fuji Xerox Co Ltd 電子素子、集積回路およびその製造方法
JP2005096024A (ja) * 2003-09-24 2005-04-14 Fuji Xerox Co Ltd ワイヤとその製造方法および該ワイヤを用いた電磁石
JP4449387B2 (ja) * 2003-09-25 2010-04-14 富士ゼロックス株式会社 複合材の製造方法
JP4380282B2 (ja) * 2003-09-26 2009-12-09 富士ゼロックス株式会社 カーボンナノチューブ複合構造体の製造方法
JP2005122930A (ja) * 2003-10-14 2005-05-12 Osaka Gas Co Ltd ナノスケールカーボンチューブペースト及び電子放出源
JP4419507B2 (ja) * 2003-10-17 2010-02-24 富士ゼロックス株式会社 コンデンサの製造方法
JP2005125187A (ja) * 2003-10-22 2005-05-19 Fuji Xerox Co Ltd ガス分解器、燃料電池用電極およびその製造方法
JP4412052B2 (ja) * 2003-10-28 2010-02-10 富士ゼロックス株式会社 複合材およびその製造方法
JP2005235728A (ja) * 2003-12-01 2005-09-02 Fuji Xerox Co Ltd 電気部材及び電気装置、並びにこれらの製造方法
JP4407263B2 (ja) * 2003-12-05 2010-02-03 東洋インキ製造株式会社 カーボンナノチューブ組成物、およびそれを含有するカーボンナノチューブ分散液
JP2007523822A (ja) * 2004-01-15 2007-08-23 ナノコンプ テクノロジーズ インコーポレイテッド 伸長した長さのナノ構造の合成のためのシステム及び方法
JP4613268B2 (ja) * 2004-01-27 2011-01-12 清水建設株式会社 球状カーボンナノチューブ集合体の製造方法
JP4501445B2 (ja) * 2004-02-06 2010-07-14 東洋インキ製造株式会社 カーボンナノチューブ組成物、およびそれを含有するカーボンナノチューブ分散液
JP4239848B2 (ja) * 2004-02-16 2009-03-18 富士ゼロックス株式会社 マイクロ波用アンテナおよびその製造方法
JP4438456B2 (ja) * 2004-03-05 2010-03-24 富士ゼロックス株式会社 電波吸収体およびその製造方法
DE102004026576A1 (de) 2004-06-01 2005-12-29 Infineon Technologies Ag Silanisierte Kohlenstoff-Nanoröhren und Verfahren zur Herstellung derselben
JP4442335B2 (ja) * 2004-06-25 2010-03-31 富士ゼロックス株式会社 デカップリング素子およびその製造方法、並びにそれを用いたプリント基板回路
JP2006008861A (ja) * 2004-06-25 2006-01-12 Fuji Xerox Co Ltd 電気部品用塗料、および塗布膜の形成方法
CA2584433A1 (en) * 2004-10-22 2006-12-21 Hyperion Catalysis International, Inc. Improved ozonolysis of carbon nanotubes
US7923403B2 (en) 2004-11-16 2011-04-12 Hyperion Catalysis International, Inc. Method for preparing catalysts supported on carbon nanotubes networks
JP4971175B2 (ja) 2004-11-16 2012-07-11 ハイピリオン カタリシス インターナショナル インコーポレイテッド カーボンナノチューブ網状組織物上に担持された触媒を製造する方法
KR101194015B1 (ko) * 2005-02-15 2012-10-24 (주)에프티이앤이 탄소 나노튜브 및 내부에 빈 공간을 가지는 탄소 나노섬유 다공성 구조체
JP4292299B2 (ja) * 2005-04-01 2009-07-08 国立大学法人東北大学 管状ナノカーボンおよび管状ナノカーボンの製造方法
ITMI20050797A1 (it) * 2005-05-03 2006-11-04 St Microelectronics Srl Metodo per crescere nanotubi di carbonio aventi predefinita chiralita'
JP2007022873A (ja) * 2005-07-20 2007-02-01 National Institute Of Advanced Industrial & Technology 水分散性蛋白質−カーボンナノチューブ複合体、その製造方法及びその用途
AU2006282930B2 (en) * 2005-08-24 2012-05-03 The Regents Of The University Of California Membranes for nanometer-scale mass fast transport
US7744793B2 (en) 2005-09-06 2010-06-29 Lemaire Alexander B Apparatus and method for growing fullerene nanotube forests, and forming nanotube films, threads and composite structures therefrom
US7850778B2 (en) * 2005-09-06 2010-12-14 Lemaire Charles A Apparatus and method for growing fullerene nanotube forests, and forming nanotube films, threads and composite structures therefrom
US20090186214A1 (en) * 2006-05-17 2009-07-23 University Of Dayton Method of growing carbon nanomaterials on various substrates
JP4706975B2 (ja) * 2006-07-10 2011-06-22 清水建設株式会社 電気二重層キャパシタ用炭素電極及び電気二重層キャパシタ用炭素電極の製造方法
US7635945B2 (en) * 2006-07-21 2009-12-22 Tsinghua University Field emission device having a hollow shaped shielding structure
JP4062346B2 (ja) * 2006-08-17 2008-03-19 富士ゼロックス株式会社 カーボンナノチューブ膜およびその製造方法、並びにそれを用いたキャパシタ
US20100051879A1 (en) * 2006-11-22 2010-03-04 The Regents od the Univesity of California Functionalized Boron Nitride Nanotubes
JP5311086B2 (ja) * 2007-02-12 2013-10-09 学校法人 名城大学 カーボンナノチューブ分散体の製造方法
US20080213367A1 (en) * 2007-03-01 2008-09-04 Cromoz Inc. Water soluble concentric multi-wall carbon nano tubes
KR100951730B1 (ko) 2007-05-30 2010-04-07 삼성전자주식회사 전도성이 개선된 카본나노튜브, 그의 제조방법 및 상기카본나노튜브를 함유하는 전극
US7894914B2 (en) * 2007-08-28 2011-02-22 Cardiac Pacemakers, Inc. Medical device electrodes including nanostructures
US7991480B2 (en) * 2007-08-28 2011-08-02 Cardiac Pacemakers, Inc. Medical device electrodes having cells disposed on nanostructures
CN101471184B (zh) * 2007-12-27 2011-11-09 清华大学 超级电容器
EP2062853A1 (en) * 2007-11-23 2009-05-27 Nanoledge Polymer carbon nanotube composites
CN101450797B (zh) * 2007-11-29 2013-05-08 索尼株式会社 处理碳纳米管的方法、碳纳米管以及碳纳米管元件
US8852547B2 (en) 2008-01-25 2014-10-07 Hyperion Catalysis International, Inc. Processes for the recovery of catalytic metal and carbon nanotubes
KR101034579B1 (ko) * 2008-03-28 2011-05-12 한화케미칼 주식회사 탄소나노튜브의 연속적인 표면처리 방법 및 장치
JP5266844B2 (ja) * 2008-03-31 2013-08-21 日本ケミコン株式会社 電気二重層キャパシタ用電極及びその製造方法
JP5303235B2 (ja) * 2008-03-31 2013-10-02 日本ケミコン株式会社 電気二重層キャパシタ用電極及びその製造方法
KR101001385B1 (ko) * 2008-04-23 2010-12-14 한화케미칼 주식회사 탄소나노튜브의 연속적인 표면처리 방법 및 장치
JP2009274900A (ja) * 2008-05-14 2009-11-26 Tatsuhiro Takahashi 低分子量ポリアニリンがグラフトしたカーボンナノチューブ及びその分散液
KR101034580B1 (ko) * 2008-05-29 2011-05-12 한화케미칼 주식회사 탄소나노튜브의 연속적인 표면처리 방법 및 장치
WO2009148959A2 (en) * 2008-05-29 2009-12-10 Lawrence Livermore National Security, Llc Membranes with functionalized carbon nanotube pores for selective transport
EP2472656A3 (en) * 2008-08-15 2013-02-20 Massachusetts Institute of Technology Layer-by-layer assemblies of carbon-based nanostructures and their applications in energy storage and generation devices
JP5604843B2 (ja) * 2008-09-30 2014-10-15 日本ケミコン株式会社 高密度カーボンナノチューブ集合体及びその製造方法
KR101147259B1 (ko) * 2008-09-30 2012-05-21 한화케미칼 주식회사 탄소나노튜브의 연속적인 정제 방법 및 장치
KR101681950B1 (ko) 2009-01-15 2016-12-05 삼성전자주식회사 그라펜 에지의 화학적 변형 방법 및 이에 의하여 얻어진 그라펜
JP5479116B2 (ja) * 2009-01-30 2014-04-23 川研ファインケミカル株式会社 分散安定性の高いカーボンナノ粒子水性分散液、その製造方法及びカーボンナノ粒子分散膜材
EP2228343A1 (en) 2009-03-13 2010-09-15 Bayer MaterialScience AG Water vapour assisted ozonolysis of carbon nanotubes
KR101470524B1 (ko) 2009-06-30 2014-12-08 한화케미칼 주식회사 혼화성이 증대된 복합탄소소재 및 이의 연속적인 제조 방법
EP2449373A1 (en) * 2009-07-01 2012-05-09 Brigham Young University Thin layer chromatography plates and related methods
US9164068B2 (en) * 2009-07-01 2015-10-20 Brigham Young University Thin layer chromatography plates and related methods
US9283541B2 (en) * 2009-07-01 2016-03-15 Brigham Young University Thin layer chromatography plates and related methods
FR2950333B1 (fr) * 2009-09-23 2011-11-04 Arkema France Procede de fonctionnalisation de nanotubes
EP2585402A2 (en) * 2010-06-22 2013-05-01 Designed Nanotubes, LLC Modified carbon nanotubes, methods for production thereof and products obtained therefrom
US9162883B2 (en) 2010-09-01 2015-10-20 International Business Machines Corporation Doped carbon nanotubes and transparent conducting films containing the same
CN103313935A (zh) 2010-12-14 2013-09-18 思迪隆欧洲有限公司 改进的弹性体配制物
JP2014507365A (ja) * 2010-12-29 2014-03-27 ▲海▼洋王照明科技股▲ふん▼有限公司 多孔質グラフェン材料、その製造方法、及び電極材料としての応用
US8754041B2 (en) 2011-03-29 2014-06-17 King Fahd University Of Petroleum And Minerals Method of removing E. coli bacteria from an aqueous solution
BR112014006025A2 (pt) * 2011-09-14 2017-06-13 Univ Rice William M métodos baseados em solvente para produção de nanofibras de grafeno
KR101329974B1 (ko) * 2012-01-12 2013-11-13 한화케미칼 주식회사 복합탄소소재를 포함하는 전자파 차폐용 수지 조성물
CA2862899C (en) 2012-01-27 2016-10-11 William Marsh Rice University Wellbore fluids incorporating magnetic carbon nanoribbons and magnetic functionalized carbon nanoribbons and methods of using the same
WO2014039509A2 (en) 2012-09-04 2014-03-13 Ocv Intellectual Capital, Llc Dispersion of carbon enhanced reinforcement fibers in aqueous or non-aqueous media
EP2973786B1 (en) 2013-03-15 2023-03-01 Wellstat BioCatalysis, LLC Methods of making nanofiber electrodes for batteries
JP5784101B2 (ja) * 2013-12-20 2015-09-24 ニッタ株式会社 Ｃｎｔネットワーク構成体の製造方法
US9840418B2 (en) 2014-06-16 2017-12-12 William Marsh Rice University Production of graphene nanoplatelets by oxidative anhydrous acidic media
CN106660786A (zh) * 2014-09-16 2017-05-10 南洋理工大学 使碳纳米材料的表面官能化的方法
US11439708B2 (en) 2014-10-06 2022-09-13 Lawrence Livermore National Security, Llc Nanotube trans-membrane channels mimicking biological porins
CA3020462C (en) 2016-04-07 2023-01-17 Molecular Rebar Design, Llc Discrete carbon nanotubes with targeted oxidation levels and formulations thereof
EP3490930A1 (en) 2016-07-27 2019-06-05 Services Petroliers Schlumberger Process for the production of dispersions of thermally oxidised carbon-based materials
KR102524467B1 (ko) * 2016-11-29 2023-04-24 비엔엔티 엘엘씨 질화붕소 나노튜브의 정제
CN110065937B (zh) * 2018-01-23 2021-12-21 清华大学 氧化多壁碳纳米管的方法
CN110350144B (zh) * 2018-04-03 2021-07-30 清华大学 电池电极、电池电极的制备方法及混合储能器件
CN110342493B (zh) * 2018-04-03 2021-07-30 清华大学 过渡金属氧化物/碳纳米管复合材料及其制备方法
CN115279711A (zh) * 2019-10-14 2022-11-01 希克里特技术有限责任公司 通过碳基纳米材料处理的胶凝复合材料
CN111302332B (zh) * 2020-04-21 2021-11-02 福建永安市永清石墨烯研究院有限公司 一种超高导热石墨烯厚膜及其制备方法
WO2023018543A1 (en) * 2021-08-09 2023-02-16 Phillips 66 Company Methods for preparing nano-ordered carbon anode materials for sodium-ion batteries

Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6159742A (en) * 1998-06-05 2000-12-12 President And Fellows Of Harvard College Nanometer-scale microscopy probes

Family Cites Families (54)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4013751A (en) * 1971-10-29 1977-03-22 Gulf Research & Development Company Fibrils and processes for the manufacture thereof
DE2363415C3 (de) * 1972-12-22 1978-06-01 Kureha Kagaku Kogyo K.K., Tokio Verfahren zur Oberflächenbehandlung von Kohlenstoff-Fasern
US4154704A (en) * 1978-01-23 1979-05-15 Chemotronics International, Inc. Activated reticulated or unreticulated carbon structures
US4329260A (en) * 1979-09-24 1982-05-11 Uop Inc. Integral shaped replication supports
US4642125A (en) * 1981-03-27 1987-02-10 Trw Inc. Carbonaceous material and methods for making hydrogen and light hydrocarbons from such materials
US4583299A (en) * 1984-12-20 1986-04-22 Trw Inc. Fluidization aid for cohesive materials
US4518575A (en) * 1982-01-28 1985-05-21 Phillips Petroleum Company Catalytic fibrous carbon
US4572813A (en) * 1983-09-06 1986-02-25 Nikkiso Co., Ltd. Process for preparing fine carbon fibers in a gaseous phase reaction
US4816289A (en) * 1984-04-25 1989-03-28 Asahi Kasei Kogyo Kabushiki Kaisha Process for production of a carbon filament
US5171560A (en) 1984-12-06 1992-12-15 Hyperion Catalysis International Carbon fibrils, method for producing same, and encapsulated catalyst
US5707916A (en) * 1984-12-06 1998-01-13 Hyperion Catalysis International, Inc. Carbon fibrils
US6375917B1 (en) 1984-12-06 2002-04-23 Hyperion Catalysis International, Inc. Apparatus for the production of carbon fibrils by catalysis and methods thereof
US5165909A (en) 1984-12-06 1992-11-24 Hyperion Catalysis Int'l., Inc. Carbon fibrils and method for producing same
US4663230A (en) 1984-12-06 1987-05-05 Hyperion Catalysis International, Inc. Carbon fibrils, method for producing same and compositions containing same
US5611964A (en) * 1984-12-06 1997-03-18 Hyperion Catalysis International Fibril filled molding compositions
US4855091A (en) 1985-04-15 1989-08-08 The Dow Chemical Company Method for the preparation of carbon filaments
US4992332A (en) * 1986-02-04 1991-02-12 Ube Industries, Ltd. Porous hollow fiber
EP0353296B1 (en) 1988-01-28 2000-05-03 Hyperion Catalysis International, Inc. Process for preparing carbon fibrils
US4997804A (en) * 1988-05-26 1991-03-05 The United States Of America As Represented By The United States Department Of Energy Low density, resorcinol-formaldehyde aerogels
IL92717A (en) 1988-12-16 1994-02-27 Hyperion Catalysis Int Fibrils
SE8900130D0 (sv) 1989-01-16 1989-01-16 Klaus Mosback Konceptet att med hjaelp av molekylavtrycksmetoden framstaella konstgjorda antikroppar genom imprinting av t ex antigener samt att framstaella konstgjorda entzymer genom imprintning med transition state analoger
AU5727290A (en) * 1989-05-15 1990-12-18 Hyperion Catalysis International Surface treatment of carbon microfibers
ZA907803B (en) 1989-09-28 1991-07-31 Hyperion Catalysis Int Electrochemical cells and preparing carbon fibrils
US5110693A (en) * 1989-09-28 1992-05-05 Hyperion Catalysis International Electrochemical cell
ATE190679T1 (de) 1989-09-28 2000-04-15 Hyperion Catalysis Int Batterie und kohlenstoffibrilbündel zur herstellung derselben
FR2664889B1 (fr) * 1990-07-17 1992-09-25 Lorraine Carbone Support poreux de membrane filtrante en composite carbone-carbone a substrat en mat de fibres de carbone et son procede de fabrication.
US5409683A (en) * 1990-08-23 1995-04-25 Regents Of The University Of California Method for producing metal oxide aerogels
US5626650A (en) * 1990-10-23 1997-05-06 Catalytic Materials Limited Process for separating components from gaseous streams
US5458784A (en) * 1990-10-23 1995-10-17 Catalytic Materials Limited Removal of contaminants from aqueous and gaseous streams using graphic filaments
US5081163A (en) * 1991-04-11 1992-01-14 The United States Of America As Represented By The Department Of Energy Melamine-formaldehyde aerogels
JP2687794B2 (ja) * 1991-10-31 1997-12-08 日本電気株式会社 円筒状構造をもつ黒鉛繊維
ATE168040T1 (de) * 1991-12-20 1998-07-15 Allied Signal Inc Materialien mit niedriger dichte und hoher spezifischer oberflaeche und daraus geformte artikel zur verwendung in der metallrueckgewinnung
US20020085974A1 (en) * 1992-01-15 2002-07-04 Hyperion Catalysis International, Inc. Surface treatment of carbon microfibers
US5372719A (en) 1992-03-30 1994-12-13 Perseptive Biosystems, Inc. Molecular imaging
US5569635A (en) 1994-05-22 1996-10-29 Hyperion Catalysts, Int'l., Inc. Catalyst supports, supported catalysts and methods of making and using the same
RU94046136A (ru) 1992-05-22 1996-09-27 Хайперион Каталайзис Интернэшнл Способ изготовления фибриллообразующего катализатора, катализатор для получения углеродных фибрилл /варианты/. способ получения углеродных фибрилл /варианты/, углеродный фибриллярный материал, носитель для катализатора, углеродная фибрилла
US5346683A (en) * 1993-03-26 1994-09-13 Gas Research Institute Uncapped and thinned carbon nanotubes and process
IL109497A (en) 1993-05-05 1998-02-22 Hyperion Catalysis Int Three-dimensional macroscopic clusters of randomly arranged charcoal fibrils and products containing these
US5641466A (en) 1993-06-03 1997-06-24 Nec Corporation Method of purifying carbon nanotubes
JP4071832B2 (ja) * 1993-09-10 2008-04-02 ハイピリオン カタリシス インターナショナル インコーポレイテッド 液体含有炭素フィブリル材料
JPH07102120A (ja) 1993-09-10 1995-04-18 Hyperion Catalysis Internatl Inc 炭素フィブリル含有ゴム組成物および空気入りタイヤ
US5439864A (en) * 1993-12-27 1995-08-08 Uop Shaped carbonaceous composition
KR970702758A (ko) 1994-04-29 1997-06-10 마이클 제이. 켈리 개선된 다이 립을 갖는 조합 롤 및 다이 피복 방법 및 장치(combination roll and die coating method and apparatus with improved die lip)
US6203814B1 (en) 1994-12-08 2001-03-20 Hyperion Catalysis International, Inc. Method of making functionalized nanotubes
US5866434A (en) * 1994-12-08 1999-02-02 Meso Scale Technology Graphitic nanotubes in luminescence assays
US20040202603A1 (en) * 1994-12-08 2004-10-14 Hyperion Catalysis International, Inc. Functionalized nanotubes
US5681657A (en) * 1995-02-02 1997-10-28 Rainer H. Frey Biocompatible porous hollow fiber and method of manufacture and use thereof
US5780101A (en) * 1995-02-17 1998-07-14 Arizona Board Of Regents On Behalf Of The University Of Arizona Method for producing encapsulated nanoparticles and carbon nanotubes using catalytic disproportionation of carbon monoxide
US5800706A (en) * 1996-03-06 1998-09-01 Hyperion Catalysis International, Inc. Nanofiber packed beds having enhanced fluid flow characteristics
BR9710708A (pt) 1996-05-15 1999-08-17 Hyperion Catalysis Int Nanofibras com alta rea de superf¡cie
DE69727671T2 (de) 1996-05-15 2004-09-30 Hyperion Catalysis International, Inc., Cambridge Starre, poröse kohlenstoffstrukturen, verfahren zu deren herstellung und verwendung und diese strukturen enthaltende erzeugnisse
CN1230283A (zh) * 1996-05-15 1999-09-29 海珀里昂催化国际有限公司 用于电化学电容器中的纳米级石墨纤维
US6683783B1 (en) * 1997-03-07 2004-01-27 William Marsh Rice University Carbon fibers formed from single-wall carbon nanotubes
ATE514804T1 (de) * 1999-07-21 2011-07-15 Hyperion Catalysis Int Verfahren zur oxidation von mehrwandigen kohlenstoffnanoröhren

Patent Citations (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US6159742A (en) * 1998-06-05 2000-12-12 President And Fellows Of Harvard College Nanometer-scale microscopy probes

Cited By (63)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20050127030A1 (en) * 2003-07-24 2005-06-16 Fuji Xerox Co., Ltd. Carbon nanotube structure, method of manufacturing the same, carbon nanotube transfer body, and liquid solution
US20130009109A1 (en) * 2003-09-08 2013-01-10 Nantero Inc. Spin-Coatable Liquid for Formation of High Purity Nanotube Films
US8628692B2 (en) * 2003-09-08 2014-01-14 Nantero Inc. Spin-coatable liquid for formation of high purity nanotube films
US8137652B2 (en) * 2003-11-03 2012-03-20 The Research Foundation Of State University Of New York Sidewall-functionalized carbon nanotubes, and methods for making the same
US20100240922A1 (en) * 2003-11-03 2010-09-23 The Research Foundation Of State University Of New York Sidewall-functionalized carbon nanotubes, and methods for making the same
US8163831B2 (en) 2004-08-31 2012-04-24 Hyperion Catalysis International, Inc. Thermosets containing carbon nanotubes by extrusion
US20080036123A1 (en) * 2004-08-31 2008-02-14 Hyperion Catalysis International, Inc. Conductive thermosets by extrusion
US7910650B2 (en) 2004-08-31 2011-03-22 Hyperion Catalysis International, Inc. Conductive thermosets by extrusion
US20110133133A1 (en) * 2004-08-31 2011-06-09 Alan Fischer Thermosets containing carbon nanotubes by extrusion
US7124764B2 (en) * 2004-12-29 2006-10-24 Industrial Technology Research Institute Method for removing impurities from porous materials
US20060137718A1 (en) * 2004-12-29 2006-06-29 Industrial Technology Research Institute Method for removing impurities from porous materials
WO2006079005A3 (en) * 2005-01-21 2007-11-15 Univ Rice William M Metal-free silicon-molecule-nanotube testbed and memory device
WO2006079005A2 (en) * 2005-01-21 2006-07-27 William Marsh Rice University Metal-free silicon-molecule-nanotube testbed and memory device
US20060223243A1 (en) * 2005-03-30 2006-10-05 Marko Radosavljevic Carbon nanotube - metal contact with low contact resistance
US20100308279A1 (en) * 2005-09-16 2010-12-09 Chaohui Zhou Conductive Silicone and Methods for Preparing Same
US20090318043A1 (en) * 2006-03-06 2009-12-24 Nanoledge Inc. Method for making polymeric extruded composite products and carbon nanotubes
US20090116170A1 (en) * 2007-11-02 2009-05-07 Tsinghua University Electrochemical capacitor with carbon nanotubes
US20090116171A1 (en) * 2007-11-02 2009-05-07 Tsinghua University Electrochemical capacitor with carbon nanotubes
US7813108B2 (en) 2007-11-02 2010-10-12 Tsinghua University Electrochemical capacitor with carbon nanotubes
US7826199B2 (en) 2007-11-02 2010-11-02 Tsinghua University Electrochemical capacitor with carbon nanotubes
US10133204B2 (en) * 2007-11-14 2018-11-20 Xerox Corporation Imaging device components comprised of hydrophobic carbon nanotubes
US7826198B2 (en) 2007-12-29 2010-11-02 Tsinghua University Electrochemical capacitor with carbon nanotubes
US20090168302A1 (en) * 2007-12-29 2009-07-02 Tsinghua University Electrochemical capacitor with carbon nanotubes
US8263698B2 (en) 2008-04-16 2012-09-11 Nissin Kogyo Co., Ltd. Carbon nanofiber, method for production thereof, method for production of carbon fiber composite material using carbon nanofiber, and carbon fiber composite material
US8415420B2 (en) 2008-04-16 2013-04-09 Nissin Kogyo Co., Ltd. Carbon nanofiber, method for production thereof, method for production of carbon fiber composite material using carbon nanofiber, and carbon fiber composite material
US20110060087A1 (en) * 2008-04-16 2011-03-10 Nissin Kogyo Co., Ltd. Carbon nanofiber, method for production thereof, method for production of carbon fiber composite material using carbon nanofiber, and carbon fiber composite material
US8679444B2 (en) 2009-04-17 2014-03-25 Seerstone Llc Method for producing solid carbon by reducing carbon oxides
US10500582B2 (en) 2009-04-17 2019-12-10 Seerstone Llc Compositions of matter including solid carbon formed by reducing carbon oxides
US9556031B2 (en) 2009-04-17 2017-01-31 Seerstone Llc Method for producing solid carbon by reducing carbon oxides
US20110141618A1 (en) * 2009-12-15 2011-06-16 Albert Wallash Use of Carbon Nanotubes to Form Conductive Gaskets Deployed in Sensitive Environments
US8274756B2 (en) * 2009-12-15 2012-09-25 HGST Netherlands B.V. Use of carbon nanotubes to form conductive gaskets deployed in sensitive environments
US9221685B2 (en) 2012-04-16 2015-12-29 Seerstone Llc Methods of capturing and sequestering carbon
US9731970B2 (en) 2012-04-16 2017-08-15 Seerstone Llc Methods and systems for thermal energy recovery from production of solid carbon materials by reducing carbon oxides
US9475699B2 (en) 2012-04-16 2016-10-25 Seerstone Llc. Methods for treating an offgas containing carbon oxides
US9090472B2 (en) 2012-04-16 2015-07-28 Seerstone Llc Methods for producing solid carbon by reducing carbon dioxide
US10106416B2 (en) 2012-04-16 2018-10-23 Seerstone Llc Methods for treating an offgas containing carbon oxides
US9637382B2 (en) 2012-04-16 2017-05-02 Seerstone Llc Methods for producing solid carbon by reducing carbon dioxide
US9796591B2 (en) 2012-04-16 2017-10-24 Seerstone Llc Methods for reducing carbon oxides with non ferrous catalysts and forming solid carbon products
US9896341B2 (en) 2012-04-23 2018-02-20 Seerstone Llc Methods of forming carbon nanotubes having a bimodal size distribution
US10815124B2 (en) 2012-07-12 2020-10-27 Seerstone Llc Solid carbon products comprising carbon nanotubes and methods of forming same
US9604848B2 (en) 2012-07-12 2017-03-28 Seerstone Llc Solid carbon products comprising carbon nanotubes and methods of forming same
US9598286B2 (en) 2012-07-13 2017-03-21 Seerstone Llc Methods and systems for forming ammonia and solid carbon products
US10358346B2 (en) 2012-07-13 2019-07-23 Seerstone Llc Methods and systems for forming ammonia and solid carbon products
US9779845B2 (en) 2012-07-18 2017-10-03 Seerstone Llc Primary voltaic sources including nanofiber Schottky barrier arrays and methods of forming same
US9650251B2 (en) 2012-11-29 2017-05-16 Seerstone Llc Reactors and methods for producing solid carbon materials
US9993791B2 (en) 2012-11-29 2018-06-12 Seerstone Llc Reactors and methods for producing solid carbon materials
US10322832B2 (en) 2013-03-15 2019-06-18 Seerstone, Llc Systems for producing solid carbon by reducing carbon oxides
US10086349B2 (en) 2013-03-15 2018-10-02 Seerstone Llc Reactors, systems, and methods for forming solid products
US10115844B2 (en) 2013-03-15 2018-10-30 Seerstone Llc Electrodes comprising nanostructured carbon
US9586823B2 (en) 2013-03-15 2017-03-07 Seerstone Llc Systems for producing solid carbon by reducing carbon oxides
US9783421B2 (en) 2013-03-15 2017-10-10 Seerstone Llc Carbon oxide reduction with intermetallic and carbide catalysts
US9783416B2 (en) 2013-03-15 2017-10-10 Seerstone Llc Methods of producing hydrogen and solid carbon
US9505621B2 (en) * 2013-03-19 2016-11-29 Nanolab, Inc. Synthesis of length-selected carbon nanotubes
US20140286852A1 (en) * 2013-03-19 2014-09-25 Nanolab, Inc. Synthesis of length-selected carbon nanotubes
US11951428B2 (en) 2016-07-28 2024-04-09 Seerstone, Llc Solid carbon products comprising compressed carbon nanotubes in a container and methods of forming same
US11752459B2 (en) 2016-07-28 2023-09-12 Seerstone Llc Solid carbon products comprising compressed carbon nanotubes in a container and methods of forming same
US11643328B2 (en) 2017-03-16 2023-05-09 Zeon Corporation Method of producing surface-treated carbon nanostructures
US11053362B2 (en) * 2017-10-11 2021-07-06 Molecular Rebar Design, Llc Mixtures of discrete carbon nanotubes
US10910636B2 (en) 2018-01-23 2021-02-02 Tsinghua University Method for making battery electrodes
US11286163B2 (en) * 2018-07-12 2022-03-29 Tsinghua University Method for making carbon nanotube arrays
EP3932861A4 (en) * 2019-03-27 2022-05-04 Osaka University METHOD OF PREPARING MATERIAL WITH MODIFIED ALLOTROPIC CARBON SURFACE, METHOD OF PREPARING MATERIAL WITH AN ALLOTROPIC CARBON SURFACE WITH INTRODUCTION OF A FUNCTIONAL GROUP AND, METHOD OF PREPARING A GRID FOR CRYOELECTRON MICROSCOPY, ORGANIC MATERIAL AND GRID FOR CRYOELECTRON
CN113646263A (zh) * 2019-03-27 2021-11-12 国立大学法人大阪大学 碳同素异形体表面经改性的物质的制造方法、碳同素异形体表面导入有官能团的物质的制造方法、冷冻电子显微镜用栅格的制造方法、有机物质、冷冻电子显微镜用栅格
CN112982027A (zh) * 2021-02-08 2021-06-18 山东仁丰特种材料股份有限公司 基于超临界流体技术高性能炭纸的改性方法

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