Discrete Carbon Nanoparticles *The Fullerenes*

1
Neat and Discrete Carbon Nanoparticles
Fullerenes and Nanotubes
2
Buckyball
What are some possible uses for a buckyball?
molecular ball bearings
drug delivery vehicles
semiconductors/transistors
The commercial applications of buckyballs are
novel yet immature in their applications.
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Fullerenes
However, the buckyball discovery has led to
research on a new class of materials called
fullerenes, or buckminsterfullerenes.

• Fullerenes are materials with
• a three dimensional network of carbon atoms,
• each atom is connected to exactly three
• neighbors, and
• each atom is bonded by two single bonds and
• one double bond (e.g., C82).

4
Fullerenes
Why is diamond not a fullerene?
Why is graphite not a fullerene?
Are fullerenes a new allotropic form of carbon?
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Fullerenes
What other questions can we ask about fullerenes?
How about Can anything be put inside of it?
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Fullerenes
Would the following fit inside of a buckyball?
An atom of nitrogen
d 120 pm
Definitely
d 700 pm
A molecule of sulfuric acid
Not likely
A molecule of hydrogen
d 150 pm
Quite possibly
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Fullerenes
Fullerenes with material inside are called cage
compounds, or endohedral compounds.
The formulas of endohedral compounds are shown as
M_at_C60where M represents the item inside of the
cage.
Examples of known compounds include N_at_C60 and
La_at_C82
What possible applications might there be for
endohedral buckyballs?
8
Fullerenes
Exohedral compounds are those in which a wide
variety of both inorganic and organic groups
added to the exterior of the cage.
These materials offer the most exciting potential
for useful applications of fullerene materials.
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Fullerenes
Combination endo- and exohedral compounds have
also been synthesized. An interesting example is
Gd_at_C82(OH)n
The gadolinium (Gd) is inside the cage and the
outside is covered with hydroxyl groups.
Gd_at_C82(OH)n is a possible enhancement material
for magnetic resonance imaging, MRI.
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Fullerenes
Commercial and biological possibilities exist
Sunscreens
due to photophysical properties
Antibacterials
due to redox and general chemical reactivity
Superconducting materials
due to physical properties
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Nanoparticles
Are there other carbon nanoparticles?
If a sheet of graphite is rolled into a cylinder,
what is wrong with this structure?
Hint dont forget about corannulene (buckybowls)!
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Nanotubes
Now you have a carbon NANOTUBE!
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Nanotube News
Cylindrical fullerene discovered in 1991
Internal cylinder diameter of 1 to 50 nm
Length of about 100 nm up to several micrometers
and longer
They can be single walled, called SWNTs, or made
up of multiple layers, called MWNTs.
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Nanotubes
Nanotubes have vastly different properties than
fullerene cages.
For example
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Nanotube News
its incredibly strong!
Why do you think nanotubes are so strong?
Hint diamonds strength is due to
Because each carbon atom in a nanotube is
covalently bonded to three others, it has great
tensile strength.
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Nanotubes
Nanotubes are also light weight, have a high
melting point, and can conduct electricity.
What are some possible uses of nanotubes?
nano-wires
nano-test tubes
nano-velcro
nano-ropes
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Nanotubes
Nano-test tubes
Inner diameter 1.2 nm
Length 2 micrometers
Volume of 10-21 liter a zeptoliter!!
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Nanoropes
Nano-ropes
Strongest fiber known 100 times stronger than
steel per gram.
What applications can you imagine for an
unbelievably strong rope or cable made of such
material?
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Far Out Application?
A space elevator--a new transport into space?
Is it possible?
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Far Out Application?
Some other things to think about
Environmental advantages
Lightning hazards
Collisions with space junk
Radiation damage to the ribbon
Is there a limit to how large it can be?
How it is initially deployed?
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Nanotech
How do you think the field of nanotechnology may
change your life for better or for worse over
the next 50 years?
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Making Connections

1. Name the three carbon allotropes.
2. Compare and contrast cylindrical and spherical
   fullerenes and their unique characteristics.
3. What are some possible applications of discrete
   carbon nanoparticles?
4. What are some possible applications of extendable
   nanoparticles?

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Module Flow Chart
Lesson 1.2 What Makes Nanoscience so Different?
What makes Nanoscience so different? Compare
Newtonian and Quantum Chemistry Regimes as they
relate to nanoscale science
Lesson 1.3 What Makes Nanoscience so
Important? Interdisciplinary science The
development of new technologies and
instrumentation applications whose risk and
benefits have yet to be determined

• Lesson 1.1 What is Nanoscience?
• What is Nanoscience?
• Examine and Compare size macro, micro,
  sub-micro (nano)
• SI prefixes

Lesson 2.1 Extendable Solids As the size of the
sample decreases the ratio of surface particles
to interior particles increases in ionic and
metallic solids
Poster Assessment Students will further
investigate the essential question that they have
considered throughout the module How and why do
the chemical and physical properties of
nanosamples differ from those of macrosamples?
Lesson 2.2 Extendable Solids Reactivity,
Catalysis, Adsorption The difference between the
energy at the surface atoms and energy of the
interior atoms results in increased surface
energy at the nanoscale Higher surface energy
allowing for increased reactivity, adsorption
and catalysis at the nanoscale
Lesson 2.3 Extendable Structures Melting Point,
Color Conductivity In Extendable
Structures Melting point decreases because
surface energy increases Color changes because
electron orbital changes with decreased particle
size Electrical conductivity decreases because
electron orbital changes with decreased particle
size
Unit 3 Lesson 2 Fullerenes and Nanotubes Fulleren
es and nanotubes are a family of carbon
allotropes They can have different shapes
(spherical and cylindrical), form endohedral,
exohedral, SWNTs and MWNTs compounds, and
demonstrate exceptional tensile strength Possible
application currently being explored
Lesson 3.1 Carbon Chemistry The molecular
geometry is related to bond number and type of
bond (single, double, and triple) The requirement
of four bonds and their alternate resonance
structures is most significant in the formation
of carbon allotropes Different allotropes can
have very different physical and chemical
properties