neat and discrete carbon nanoparticles fullerenes and nanotubes
TRANSCRIPT
Neat and Discrete Carbon Nanoparticles
Fullerenes and Nanotubes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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What are some possible uses for a buckyball?
• semiconductors/transistors
• molecular ball bearings
• drug delivery vehicles
The commercial applications of buckyballs are novel yet immature in their applications.
Buckyball
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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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).
However, the buckyball discovery has led to research on a new class of materials called fullerenes, or buckminsterfullerenes.
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Why is graphite not a fullerene?
Why is diamond not a fullerene?
Are fullerenes a new allotropic form of carbon?
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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What other questions can we ask about fullerenes?
How about: “Can anything be put inside of it?”
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Would the following fit inside of a buckyball?
An atom of nitrogen
Definitely
A molecule of sulfuric acid
Not likely
A molecule of hydrogen
Quite possibly
d = ~120 pm
d = ~150 pm
d = ~700 pm
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Fullerenes with material inside are called cage compounds, or endohedral compounds.
The formulas of endohedral compounds are shown as M@C60—where M represents the item inside of the cage.
Examples of known compounds include:N@C60 and La@C82
What possible applications might there be for endohedral buckyballs?
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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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.
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Combination endo- and exohedral compounds have also been synthesized. An interesting example is:
The gadolinium (Gd) is inside the cage and the outside is covered with hydroxyl groups.
Gd@C82(OH)n is a possible enhancement material for magnetic resonance imaging, MRI.
Gd@C82(OH)n
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Commercial and biological possibilities exist:
Sunscreens
Superconducting materials
Antibacterials
due to photophysical properties
due to redox and general chemical reactivity
due to physical properties
Fullerenes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Are there other carbon nanoparticles?
Hint: don’t forget aboutcorannulene (buckybowls)!
If a sheet of graphite is rolled into a cylinder, what is wrong with this structure?
Nanoparticles
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Now you have a carbon NANOTUBE!
Nanotubes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Cylindrical fullerene discovered in 1991
Internal cylinder diameter of 1 to 50 nm
They can be single walled, called SWNTs, or made up of multiple layers, called MWNTs.
Length of about 100 nm up to several micrometers and longer
Nanotube News
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Nanotubes have vastly different properties than fullerene cages.
For example…
Nanotubes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Why do you think nanotubes are so strong?
… it’s incredibly strong!
Hint: diamond’s strength is due to…
Because each carbon atom in a nanotube is covalently bonded to three others, it has great tensile strength.
Nanotube News
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Nanotubes are also light weight, have a high melting point, and can conduct electricity.
What are some possible uses of nanotubes?
nano-wires
nano-ropes
nano-velcronano-test tubes
Nanotubes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Nano-test tubes
Inner diameter ~1.2 nm
Length ~ 2 micrometers
Volume of 10-21 liter — a zeptoliter!!
Nanotubes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Nano-ropesStrongest 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?
Nanoropes
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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A space elevator--a new transport into space?
Is it possible?
Far Out Application?
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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Some other things to think about:
Environmental advantages
Lightning hazards
Collisions with space junk
Is there a limit to how large it can be?
How it is initially deployed?
Radiation damage to the ribbon
Far Out Application?
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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How do you thinkthe field of
nanotechnology may change
your life— for better or for worse —
over the next50 years?
Nanotech
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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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?
Making Connections
Neat and Discrete Carbon Nanoparticles: Fullerenes and Nanotubes© McREL 2009
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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 2.2 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 nanoscaleHigher surface energy allowing for increased reactivity, adsorption and catalysis at the nanoscale
Lesson 2.3Extendable Structures: Melting Point, Color Conductivity
In Extendable Structures:Melting point decreases because surface energy increasesColor changes because electron orbital changes with decreased particle sizeElectrical conductivity decreases because electron orbital changes with decreased particle size
Unit 3 Lesson 2Fullerenes and Nanotubes
Fullerenes 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 strengthPossible application currently being explored
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 3.1Carbon 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 allotropesDifferent allotropes can have very different physical and chemical properties
Module Flow Chart