Honda Motor Co., Ltd.

The Ohio State University

Elena Mora

Avetik R Harutyunyan

Toshio Tokune

John M Pigos

The present disclosure is directed to a method for producing SWCNT from endothermic carbon-containing feedstock, such as, methane gas, using an activated alumina supported Fe:Mo catalyst. The SWCNT growth temperature is less than about 560&#xb0; C., and the catalyst is activated by exposure to a reducing atmosphere at a temperature greater than about 900&#xb0; C.

Low temperature single-wall carbon nanotube synthesis

Methods and processes for synthesizing high quality carbon single-walled nanotubes (SWNTs) are provided. The method provides the means for optimization of amount of carbon precursor and transport gas per unit weight of catalyst. In certain aspects, methods are provided wherein a supported metal catalyst is contacted with a carbon precursor gas at about one atmosphere pressure, wherein SWNTs are synthesized at a growth rate of about 0.002 &#x3bc;m/sec to about 0.003 &#x3bc;m/sec and the SWNTs have a ratio of G-band to D-band in Raman spectra (I:I) of greater than about 4. Efficiencies of about 20% can be achieved when contacting the catalyst deposited on a support with a carbon precursor gas with a flow rates of about 4.2&#xd7;10mol CH/sec&#xb7;g (Fe) at 780&#xb0; C. Hydrocarbon flow rates of about 1.7 10mol CH/sec&#xb7;g (Fe) and higher result in faster carbon SWNTs growth with improved quality. Slower rates of carbon atoms supply (&#x2dc;4.5&#xd7;10C atoms/s&#xb7;g Fe or 6.4&#xd7;10mol CH/sec&#xb7;g (Fe)) result in the formation of more defective nanotubes.

Effect of hydrocarbon and transport gas feedstock on efficiency and quality of grown single-walled nanotubes

Methods and processes for synthesizing single-wall carbon nanotubes are provided. A carbon precursor gas is contacted with metal catalysts deposited on a support material. The metal catalysts are preferably nanoparticles having diameters less than about 3 nm. The reaction temperature is selected such that it is near the eutectic point of the mixture of metal catalyst particles and carbon. Further, the rate at which hydrocarbons are fed into the reactor is equivalent to the rate at which the hydrocarbons react for given synthesis temperature. The methods produce carbon single-walled nanotubes having longer lengths.

Catalyst for the growth of carbon single-walled nanotubes

The present teachings are directed toward a matrix containing nanosized metal components and carbon nanotubes, with the carbon nanotubes being produced in situ by the nanosized metal components upon the contacting of the nanosized metal components with a carbon source under conditions sufficient to produce the carbon nanotubes. Also disclosed are methods of producing the matrix containing the nanosized metal components and carbon nanotubes.

Method of preparing carbon nanotube containing electrodes

The present teachings are directed toward methods of determining the lifetime of a catalyst for producing carbon nanotubes. The methods include providing different isotopically-labeled reaction components, primarily hydrocarbon sources containing different carbon isotopes, to the catalyst and measuring the Raman spectra of the carbon nanotubes produced with the different hydrocarbon sources.

Method of determining lifetime of a nanotube-producing catalyst

Methods and processes for synthesizing single-wall carbon nanotubes are provided. A carbon precursor gas is contacted with metal catalysts deposited on a support material. The metal catalysts are preferably nanoparticles having diameters less than about 3 nm. The reaction temperature is selected such that it is near the eutectic point of the mixture of metal catalyst particles and carbon. Further, the rate at which hydrocarbons are fed into the reactor is equivalent to the rate of formation of carbon SWNTs for given synthesis temperature. The methods produce carbon single-walled nanotubes having longer lengths.

Growing community of inventors

Columbus, OH, United States of America

Elena Mora