Macroscopic ordered assembly of carbon nanotubes

Abstract

The present invention is directed to the creation of macroscopic materials and objects comprising aligned nanotube segments. The invention entails aligning single-wall carbon nanotube (SWNT) segments that are suspended in a fluid medium and then removing the aligned segments from suspension in a way that macroscopic, ordered assemblies of SWNT are formed. The invention is further directed to controlling the natural proclivity or nanotube segments to self assemble into or ordered structures by modifying the environment of the nanotubes and the history of that environment prior to and during the process. The materials and objects are “macroscopic” in that they are large enough to be seen without the aid of a microscope or of the dimensions of such objects. These macroscopic ordered SWNT materials and objects have the remarkable physical, electrical, and chemical properties that SWNT exhibit on the microscopic scale because they are comprised of nanotubes, each of which is aligned in the same direction and in contact with its nearest neighbors. An ordered assembly of closest SWNT also serves as a template for growth of more and larger ordered assemblies. An ordered assembly further serves as a foundation for post processing treatments that modify the assembly internally to specifically enhance selected material properties such as shear strength, tensile strength, compressive strength, toughness, electrical conductivity, and thermal conductivity.

Description

[0001]This invention was made with Government support under Grant No. NCC9-77 and Grant No. N00014-99-1-0246 awarded by the National Aeronautical and Space Administration and Office of Naval Research, respectively. The Government may have certain rights in the invention.BACKGROUND OF THE INVENTION[0002]Fullerenes are closed-cage molecules composed entirely of sp2-hybridized carbons, arranged in hexagons and pentagons. Fullerenes (e.g., C60) were first identified as closed spheroidal cages produced by condensation from vaporized carbon.[0003]Fullerene tubes are produced in carbon deposits on the cathode in carbon are methods of producing spheroidal fullerenes from vaporized carbon. Ebbesen et al. (Ebbesen I), “Large-Scale Synthesis Of Carbon Nanotubes,”Nature, Vol. 358. p. 220 (Jul. 16, 1992) and Ebbesen et al., (Ebbesen II), “Carbon Nanotubes,”Annual Review of Materials Science. Vol. 24, p. 235 (1994). Such tubes are referred to herein as carbon nanotubes. Many of the carbon nanotub...

AI Technical Summary

Benefits of technology

[0027]It is a technical advantage of the present invention that a method for chemical manipulation of single-wall carbon nanotubes that enables production of large ropes and a macroscopic ordered assembly of carbon nanotubes is disclosed.

[0028]It is technical advantage of the present invention that a method for magnetic manipulation of single-wall carbon nanotubes and ropes is disclosed

[0029]It is a technical advantage of the present invention that methods for producing a macroscopic ordered assembly of carbon nanotubes are disclosed. It is a technical advantage of the present invention that methods for post processing a macroscopic ordered assembly of carbon nanotubes that modify the properties of said assembly and are fundamentally enabled by the assembly's structure are disclosed.

[0030]The foregoing objectives, the compositions of matter produced by them and other objectives apparent to those skilled in the art, are achieved according to the present invention as described and claimed herein.

[0031]The ordered assemblies also are important in their service as a substrate for initiation of growth of more and larger ordered assemblies of nanotubes. Here, the ordered assembly is cut in a direction perpendicular to that of the tube axes. The exposed surface is then cleaned and made uniform using electrochemical polishing or other means known to those skilled in the art of surface science

Problems solved by technology

While this are discharge process can produce single-wall nanotubes, the yield of nanotubes is low and the tubes exhibit significant variations in struc

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