Hyperion Catalysis International, Inc.

Hyperion Catalysis Int'l Inc.

Hyperlon Catalysis Int'l., Inc.

Asif Chishti

David Moy

Chunming Niu

Robert Hoch

Howard G Tennent

Jun Ma

Robert W Hausslein

Stephen O Friend

Jun Yang

Jaspard Harvey Atkins

Jaspard H Atkins

Methods of oxidizing multiwalled carbon nanotubes are provided. The multiwalled carbon nanotubes are oxidized by contacting the carbon nanotubes with gas-phase oxidizing agents such as CO, O, steam, NO, NO, NO, O, and ClO. Near critical and supercritical water can also be used as oxidizing agents. The multiwalled carbon nanotubes oxidized according to methods of the invention can be used to prepare rigid porous structures which can be utilized to form electrodes for fabrication of improved electrochemical capacitors.

Methods of oxidizing multiwalled carbon nanotubes

An improved catalyst for producing carbon fibrils is made by incorporating an effective yield-enhancing amount of a carboxylate into a fibril-forming catalyst. Alternatively, such a catalyst is made by coprecipitating a compound of a metal having fibril-forming catalytic properties and an aluminum and/or magnesium compound, optionally in the presence of carbon particles or carbon fibril aggregates. The catalyst may also be made by incorporating a compound of a fibril-forming metal onto magnesia particles in carbon particles or carbon fibril aggregates. The catalysts, methods of using them to form carbon fibrils and those carbon fibrils are also disclosed.

Methods and catalysts for the manufacture of carbon fibrils

A new method for preparing a supported catalyst is herein provided. Carbon nanotubes are functionalized by contacting them with an oxidizing agent to form functionalized carbon nanotubes. A metal catalyst is then loaded or deposited onto the functionalized carbon nanotubes. The mixture is then extruded to form the supported catalyst comprising a carbon nanotube structure containing metal catalyst more evenly dispersed within the internal structure of the carbon nanotube structure.

Methods of preparing supported catalysts from metal loaded carbon nanotubes

A process for producing hollow, single-walled carbon nanotubes by catalytic decomposition of one or more gaseous carbon compounds by first forming a gas phase mixture carbon feed stock gas comprising one or more gaseous carbon compounds, each having one to six carbon atoms and only H, O, N, S or Cl as hetero atoms, optionally admixed with hydrogen, and a gas phase metal containing compound which is unstable under reaction conditions for said decomposition, and which forms a metal containing catalyst which acts as a decomposition catalyst under reaction conditions; and then conducting said decomposition reaction under decomposition reaction conditions, thereby producing said nanotubes.

Process for producing single wall nanotubes using unsupported metal catalysts and single wall nanotubes produced according to this method

A process for producing hollow, single-walled carbon nanotubes by catalytic decomposition of one or more gaseous carbon compounds by first forming a gas phase mixture carbon feed stock gas comprising one or more gaseous carbon compounds, each having one to six carbon atoms and only H, O, N, S or el as hetero atoms, optionally admixed with hydrogen, and a gas phase metal containing compound which is unstable under reaction conditions for said decomposition, and which forms a metal containing catalyst which acts as a decomposition catalyst under reaction conditions; and then conducting said decomposition reaction under decomposition reaction conditions, thereby producing said nanotubes.

A method of chemically modifying carbon nanotubes having a diameter less than one micron comprising: contacting the nanotubes with a peroxygen compound selected from the group consisting of organic peroxyacids, inorganic peroxoacids and organic hydroperoxides, or a salt thereof, under oxidation conditions and thereby producing modified carbon nanotubes. Oxidation of the nanotubes increases the degree of dispersion of aggregates of nanotubes and aids in the disassembling of such aggregates. The dispersed nanotubes are used to prepare rigid structures and can be used in electrodes and capacitors.

Modification of nanotubes oxidation with peroxygen compounds

Catalysts for the manufacture of carbon fibrils and methods of use thereof

A catalyst for the production of carbon fibrils and a method for the manufacture of such a catalyst comprising contacting a fibril-forming catalyst or precursors of a fibril-forming catalyst with an effective amount of a surfactant and/or polyol. The improved carbon fibrils or carbon fibril aggregates produced using the catalyst are free of a continuous carbon thermal overcoat, with graphitic layers substantially parallel to the fibril axis, and have a substantially constant diameter from about 1.0 to 100 nanometers. The improved carbon fibrils possess enhanced dispersion in composite materials and provide enhanced electrical conductivity in those materials.

A fibril aggregate that includes a multiplicity of carbon fibrils whose longitudinal axes have substantially the same relative orientation, each of the fibrils characterized as having graphitic layers that are substantially parallel to its longitudinal axis and being free of a continuous thermal carbon overcoat, and a method of preparing such aggregates.

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Lowell, MA, United States of America

Asif Chishti