Abstract:
In a method for forming a carbon nanotube (5) on an electroconductive member (2), a catalytic layer (3) including a metal or alloy that serves as a catalyst for growing the carbon nanotube is formed on an electroconductive member, the metal or alloy of the catalytic layer is processed so as to turn it into small particles (3a) by heating the catalytic layer formed on the electroconductive member to a prescribed temperature while supplying inert gas, and a carbon nanotube is grown on the electroconductive member by using the small particles of the metal or alloy of the catalytic layer as a catalyst. The fine metallic particles that can be used as a catalyst for growing the carbon nanotube can be prepared in a simple, economical and efficient manner. The carbon nanotube is highly suitable for use as the diffusion layer of a fuel cell.
Abstract:
This invention provides a method for making a catalyst for use in the preparation of carbon nanotubes, which method comprises subjecting a thin film of a catalytic metal on a support to selective mechanical or electromagnetic modification to enhance the grain size of the metal. This invention also provides a modified thin film of a catalytic metal on a support that is useful for the selective area growth of carbon nanotubes, which modification is selective in area and is made through mechanical or electromagnetic means to enhance the grain size of the metal. This invention also provides a process for the selective area growth of carbon nanotubes on a substrate which bears a catalyst thin film, the process comprising contacting a modified thin film catalyst defined above with a carbon source under pressure and temperature conditions which promote carbon nanotube synthesis. This invention also provides the use of the modified surface deposited carbon nanotubes for the manufacture of display, electronic and microelectromechanical devices.
Abstract:
A method is described for the continuous production of nanotubes comprising forming a plasma jet, introducing into the plasma jet a metal catalyst or metal catalyst precursor to produce vaporised catalyst metal, directing one or more streams of quenching gas into the plasma to quench the plasma and passing the resulting gaseous mixture through a furnace, one or more nanotube forming materials being added whereby nanotubes are formed therefrom under the influence of the metal catalyst and are grown to a desired length during passage through the furnace, and collecting the nanotubes so formed.
Abstract:
A method for preparing a functional nano−material utilizing an endothermic reaction, characterized in that in a process of preparing a multilayer carbon nanotube (3) by the chemical vapor−phase deposition method or liquid−phase deposition method, a reaction auxiliary (H 2 S) undergoing an endothermic reaction is added in addition to the main reactants (CH 4 , H 2 ) for the chemical vapor−phase deposition method or liquid−phase deposition method, to thereby form a single−layer carbon nanotube (4). A method essentially the same as the above method can be used for preparing, in addition to a single−layer carbon nanotube, a single−layer boron nitride nanotube, a single−layer silicon carbide nanotube, a multilayer carbon nanotube having a controlled number of layer, a multilayer boron nitride nanotube having a controlled number of layer, a multilayer silicon carbide nanotube having a controlled number of layer, a metal−included fullerene or a metal−included fullerene having a controlled number of layer in good yield.
Abstract:
The invention relates to a process for formation of carbon nanotubes. The process comprises laser ablation of a bulk metal catalyst within a hydrocarbon solution to produce a feedstock containing metal catalyst nanoparticles. The feedstock is atomizing to form a feedstock aerosol. The aerosol is heated to form naotubes. An apparatus for forming carbon nanotubes is also disclosed. Nanoparticles formed in the feedstock according to the invention can be controlled to achieve a narrow size distribution, which ultimately allows for good control over size and chirality of the nanotubes formed.
Abstract:
The present invention is related to single and/or multiple-wall carbon nanotubes which may contain interstitial metals obtainable by a preparation process, comprising a catalytic step using a catalytic system, said catalytic system comprising a catalyst and a support, said support comprising hydroxides and/or carbonates or mixtures thereof with or without metal oxides. The present invention is also related to carbon fibres obtainable by said preparation process. The present invention also pertains in particular to said catalytic system and to said preparation process. Another aspect concerns the use of the nanotubes and of the catalytic system according to the invention.
Abstract:
Methods of preparing dispersions of carbon-based materials are disclosed herein. In some embodiments, a method comprises exposing the carbon-based material to an atmosphere comprising between about 0.5% v/v and about 5.0% v/v of oxygen for a selected time at an oxidation temperature to obtain a thermally oxidized material; and dispersing the thermally oxidized material in a liquid medium.
Abstract:
Metal-carbon nanotube composites having nanotubes which are uniformly dispersed within the metal matrix of the composite, and which are unbundled or substantially unbundled, have high lengths, and which can be controllably aligned are disclosed herein. Such metal-carbon nanotube composites can show improved electrical, thermal, and mechanical properties, as compared to a pristine metal or metal alloy which does not contain nanotubes dispersed therein. Facile and scalable methods of fabricating such metal-nanocarbon composites are also disclosed.