Carbon nanotubes. John, Sarah, Doug. Carbon nanotubes. Main interest: Prototypes for a one-dimensional quantum wire. Strength . Who found first nanotube?.
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Prototypes for a one-dimensional quantum wire.
1970: Morinobu Endo-- First carbon filaments of nanometer dimensions, as part of his PhD studies at the University of Orleans in France. He grew carbon fibers about 7 nm in diameter using a vapor-growth technique. Filaments were not recognized as nanotubes and were not studied.
1991:Sumio Iijima-- NEC Laboratory in Tsukuba-- used high-resolution transmission electron microscopy to observe carbon nanotubes.
An ideal nanotube can be thought of as a hexagonal network of carbon atoms that has been rolled up to make a cylinder.
width: nanometer: "capped" with half of a fullerene molecule.
(n, 0) or (0, m) and have a chiral angle of 0°, armchair nanotubes have (n, n) and a chiral angle of 30°, while chiral nanotubes have general (n, m) values and a chiral angle of between 0° and 30°.
Quote: “Since each unit cell of a nanotube contains a number of hexagons, each of which contains two carbon atoms, the unit cell of a nanotube contains many carbon atoms. If the unit cell of a nanotube is N times larger than that of a hexagon, the unit cell of the nanotube in reciprocal space is 1/N times smaller than that of a single hexagon. “
Let us break this down!
Then in reciprocal space:
(pi/L) = (pi/a N) = (pi/a)(1/N)
For k space
Then because we have a cylinder:
E(kxn , ky)
Kxn = ((2*pi) /P) * n
n=1,2,3 …(1-D bands)
Scanning electron microscope: looks like a mat of carbon ropes Ropes are between 10 and 20 nm across and 100 µm long.
Transmission electron microscope: each rope is found to consist of a bundle of single-wall carbon nanotubes aligned along a single direction.
X-ray diffraction, which views many ropes at once, shows that the diameters of the single-wall nanotubes have a narrow distribution with a strong peak.