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Neat and Discrete Carbon Nanoparticles

Neat and Discrete Carbon Nanoparticles. Fullerenes and Nanotubes. Buckyball. What are some possible uses for a buckyball?. • molecular ball bearings. • drug delivery vehicles. • semiconductors/transistors.

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Neat and Discrete Carbon Nanoparticles

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  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.

  3. Fullerenes However, the buckyball discovery has led to research on a new class of materials called fullerenes, or buckminsterfullerenes. • Fullerenesare materials with: • athree dimensionalnetwork ofcarbonatoms, • each atom is connected to exactlythree • neighbors, and • each atom is bonded bytwo singlebonds and • one doublebond (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?

  5. Fullerenes What other questions can we ask about fullerenes? How about: “Can anything be put inside of it?”

  6. Fullerenes Would the following fit inside of a buckyball? d = ~120 pm An atom of nitrogen Definitely d = ~700 pm A molecule of sulfuric acid Not likely A molecule of hydrogen d = ~150 pm Quite possibly

  7. Fullerenes 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?

  8. Fullerenes Exohedralcompounds 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.

  9. Fullerenes Combination endo- and exohedral compounds have also been synthesized. An interesting example is: Gd@C82(OH)n 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.

  10. 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

  11. Nanoparticles Are there other carbon nanoparticles? If a sheet of graphite is rolled into a cylinder, what is wrong with this structure? Hint: don’t forget about corannulene (buckybowls)!

  12. Nanotubes Now you have a carbon NANOTUBE!

  13. 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.

  14. Nanotubes Nanotubes have vastly different properties than fullerene cages. For example…

  15. Nanotube News … it’s incredibly strong! Why do you think nanotubes are so 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.

  16. 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

  17. Nanotubes Nano-test tubes Inner diameter ~1.2 nm Length ~ 2 micrometers Volume of 10-21 liter — a zeptoliter!!

  18. 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?

  19. Far Out Application? A space elevator--a new transport into space? Is it possible?

  20. 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?

  21. Nanotech How do you think the field of nanotechnology may change your life — for better or for worse — over the next 50 years?

  22. Making Connections • Name the three carbon allotropes. • Compare and contrast cylindrical and spherical fullerenes and their unique characteristics. • What are some possible applications of discrete carbon nanoparticles? • What are some possible applications of extendable nanoparticles?

  23. Module Flow Chart Lesson 1.1 What is Nanoscience? What is Nanoscience? Examine and Compare size: macro, micro, sub-micro (nano) SI prefixes 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 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 2.1Extendable Solids As the size of the sample decreases the ratio of surface particles to interior particles increases in ionic and metallic solids Lesson 2.2Extendable 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 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 Unit 3 Lesson 2 Fullerenes 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 strength Possible application currently being explored

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