2. Lecture
Carbon nanotubes
Structure
Eva Košťáková
KNT, FT, TUL
Carbon
Carbon (from Latin: carbo "coal") is the chemical element with
symbol C and atomic number 6.
Carbon is the 15th most abundant element in the Earth's crust,
and the fourth most abundant element in the universe by mass
after hydrogen, helium, and oxygen. It is present in all known
life forms, and in the human body carbon is the second most
abundant element by mass (about 18.5%) after oxygen.
There are several allotropes of carbon of which the best
known are graphite, diamond, and amorphous carbon.
Diamond
Fulerene C60
Amorphous
carbon
Graphite
Fulerene C250
Carbon
nanotube
Diamond
and
graphite
Graphite
Fullerens
A fullerene is any molecule composed entirely of carbon, in the
form of a hollow sphere, ellipsoid or tube. Spherical fullerenes are
also called buckyballs, and they resemble the balls used in
football (soccer). Cylindrical ones are called carbon nanotubes or
buckytubes. Fullerenes are similar in structure to graphite, which
is composed of stacked graphene sheets of linked hexagonal
rings; but they may also contain pentagonal (or sometimes
heptagonal) rings.
Richard Buckminster Fullera == Buckminsterfullerene C60
The first fullerene to be discovered, and the family's
namesake, was buckminsterfullerene C60, made in 1985 by
Robert Curl, Harold Kroto and Richard Smalley.
By 1991, it was relatively easy to produce gram-sized samples
of fullerene powder
Kroto, Curl, and Smalley were awarded the 1996 Nobel Prize
in Chemistry for their roles in the discovery of this class of
compounds
Nobel price in chemistry - 1996
nano-onions
Fullerene (Buckyball) colloids, 1,000,000X.
The nucleus to nucleus diameter of a
C60 molecule is about 0.71 nm
http://www.nature.com/nnano/journal/v1/n2/full/nnano.2006.62.html
Cylindrical fullerenes are called carbon
nanotubes or buckytubes.
A large percentage of academic and popular
literature attributes the discovery of hollow,
nanometer-size tubes composed of graphitic carbon
to Sumio Iijima in 1991.
Sumio Iijima (born 1939) is a Japanese physicist,
often cited as the discoverer of carbon nanotubes.
SWNTs (single wall nanotubes)
Diameter of SWNTs
Optimal 1,4nm
Possible 0,4 – 2,5 nm
Carbon nanotubes - structure
a) Zigzag structure
b) Armchair structure
c) Chiral structure
3. CARBON NANOTUBES, NANOFIBERS AND NANOWIRES
1
„chiral"
"zig-zag"
MWNTs (multi wall nanotubes)
TEM microstructure of MWNTs and nanoparticle
c-MWNTs (multi wall nanotubes)
cb-MWNTs (bamboo multi wall nanotubes)
h-MWNTs ( herringboneMWNTs)
hb-MWNTs (bamboo herringbone multi wall nanotubes)
Hetero-nanotubes
X@SWNT or X@MWNT - Hybrid carbon nanotubes
An uncapped single-wall carbon nanotube with
encapsulated buckyballs. This type of tube is
sometimes referred to as a ‘peapod’ carbon nanotube.
This electron micrograph offers a detailed view of silver beads and the eroded layers
of the nanotube.
Ag
MWNT
http://gtresearchnews.gatech.edu/newsrelease/NANOTUBE.html
Carbon nanotubes price
SWNTs – 70%purity 1g = 300Euro
MWNTs – 90%purity 1kg = 1000Euro
MWNTs – 95%purity 1g = 40 Euro
MWNTs – 95%purity surface modified 1g = 50-65Euro
MWNTs orientation
Carbon nanofibers: no hollow, diameter between
50-200nm,
micrometers.
length
–
several
Carbon nanotubes: presence of hollow,
from 1nm to several tens of micrometers (It
depends on number of walls), length – several
micrometers.
Nanowires:
presence of hollow, - Not from
CARBON, from 1nm to several tens of
micrometers (It depends on number of walls),
length – several micrometers.
3. CARBON NANOTUBES, NANOFIBERS AND NANOWIRES
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