A method of producing a carbon nanostructure is provided that enables production of a high-quality carbon nanostructure with a high yield. The method of producing a carbon nanostructure includes supplying a feedstock gas to a catalyst and growing a carbon nanostructure by chemical vapor deposition. A gas X that is derived from the feedstock gas and that comes into contact with the catalyst contains a hydrocarbon A having at least one cyclopentadiene skeleton and a hydrocarbon B having at least one acetylene skeleton. A total volume concentration [A] of the hydrocarbon A is at least 0.06%.

The present invention provides a conductive material for a secondary battery, and a secondary battery containing the same, the conductive material comprising carbon nanotubes, having a secondary structure in which carbon nanotube units having a diameter of 20-150 nm are entangled, having a ratio of true density to bulk density (TD/BD) of 30-120, having a metal content of 50 ppm or less, and having both excellent dispersibility and high purity, thereby being capable of improving, by increasing the conductivity within an electrode, battery performance, particularly, battery performance at room temperature and low temperature when applied to a battery.

The present invention relates to a method for producing large-diameter, low-density carbon nanotubes. The method uses a catalyst containing spherical -alumina that is capable of controlling the growth of carbon nanotubes without deteriorating the quality of the carbon nanotubes. The use of the catalyst makes the carbon nanotubes highly dispersible.

Provided is an electrode mixture layer capable of reducing internal resistance by use of a carbon nanotube molding. The electrode mixture layer includes an active material and a conductor of carbon nanotubes in close contact with the surface of the active material, and the number density of the carbon nanotubes is 4 tubes/m or more. The number density is defined as a value obtained by providing measurement lines on a scanning electron microscope image of a surface of the electrode mixture layer at 0.3 m intervals both longitudinally and laterally, measuring the total number of the carbon nanotubes being in close contact with the surface of the active material and intersecting the measurement lines, and dividing the total number of the carbon nanotubes by the total length of the measurement lines on the active material surface.

The present invention relates to a catalyst for synthesizing multi-wall carbon nanotubes and, more specifically, to a catalyst for synthesizing multi-wall carbon nanotubes, capable of easily disperse the synthesized multi-wall carbon nanotubes and significantly improving conductivity, to a method for producing the catalyst, and to multi-wall carbon nanotubes synthesized by the catalyst.

Provided is a supported catalyst for producing carbon nanotubes with a large specific surface area. The supported catalyst enables the production of carbon nanotubes with a large specific surface area in high yield. Therefore, the catalyst can be used in various fields. Also provided are carbon nanotubes produced using the supported catalyst.

Provided is a carbon film including: a plurality of fibrous carbon nanostructures; and a conductive carbon, wherein the plurality of fibrous carbon nanostructures has a BET specific surface area of 500 m.sup.2/g or more. Also provided is a method of producing a carbon film, the method including mixing a conductive carbon into a fibrous carbon nanostructure dispersion liquid containing a plurality of fibrous carbon nanostructures having a BET specific surface area of 500 m.sup.2/g or more, a dispersant, and a solvent, and subsequently removing the solvent to form a carbon film.

One embodiment of the present disclosure provides a catalyst for manufacturing carbon nanotubes, including a metal component represented by the following Chemical Formula 1:

Co.sub.x:[M1,Zr].sub.y:M2.sub.z[Chemical Formula 1] wherein Co represents cobalt or oxides or derivatives thereof, M1 represents at least one metal, or oxides or derivatives thereof, selected from Al, Ca, Si, Ti, and Mg, Zr represents zirconium, or oxides or derivatives thereof, M2 represents at least one metal, or oxides or derivatives thereof, selected from W, V, Mn, and Mo, x/y satisfies 0.2x/y2.6, and x/z satisfies 6x/z13.

A multiwalled carbon nanotube includes at least 2 carbon nanotube walls. The multiwalled carbon nanotube have an outer surface and at least a portion of an oxygen functional group is attached to the outer surface thereof. Up to 5 atomic percent of the multiwalled carbon nanotube surface is an oxygen functional group. The surface atomic ratio of carbon to oxygen is between 17:1 and 19:1. A photocatalysis process to produce hydrogen and at least one solid carbon nanostructure includes the steps of: applying light to saturated hydrocarbons in the presence of a metal particle supported metal oxide photocatalyst to produce at least hydrogen gas and at least one solid carbon nanostructure; separating the hydrogen from at least one solid carbon nanostructure; and collecting the separated hydrogen and the at least one solid carbon nanostructure.

High-surface area carbon nanotubes having targeted, or selective, species of oxygen containing species levels, types and/or content on either or both of the interior and exterior of the tube walls are claimed. Such carbon nanotubes can have little to none inner tube surface oxygen containing species, or differing amounts and/or types of oxygen containing species between the tubes' inner and outer surfaces or amongst the carbon nanotubes. Additionally, such high-surface area carbon nanotubes or their assemblages may have greater lengths and diameters, creating useful mechanical, electrical, and thermal properties.