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Carbon Nanotubes. Zach Blankenship, Jeff Harwell, Tony Mondejar. Today's Presentation. Introduction What is a Nanotube History of Nanotube Research Nanotube Structure and Properties Applications of Nanotubes Conclusion. Introduction. Why are we interested in Nanotube development?
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Carbon Nanotubes Zach Blankenship, Jeff Harwell, Tony Mondejar
Today's Presentation • Introduction • What is a Nanotube • History of Nanotube Research • Nanotube Structure and Properties • Applications of Nanotubes • Conclusion
Introduction • Why are we interested in Nanotube development? • What is a Nanotube? • History of the Nanotube? • How was it discovered…(who, where and when)? • What are different kinds of Nanotubes? • What are some properties of a Nanotube? • What is Nanotechnology? • Applications of Nanotechnology?
Chronological Milestones • 1985 Researchers discover soccer ball shaped molecule created by linking together 60 or more carbon atoms. It was later named after R. Buckmister Fuller (buckyballs). • 1991 Observation and identification of nanotubes in fullerene soot by Sumio Iijima. • 1992 Predictions of metallic/insulating properties. • 1993 Synthesis of single-walled nanotubes.
Chronological Milestones • 1996 Measurement of individual multiwalled tubes. • 1996 Individual nanotube used as an AFM tip. • 1996 Production of bulk, monodisperse 1.4 nm SWNTs. • 1997 Observation of single-electron effects in individual SWNTs and bundles.
Properties of Fullerene Nanotubes • Pure form of Carbon • Structure • Conductivity • Tensile Strength • Elasticity
Carbon Nanotubes Forms of Carbon mmptdpublic.jsc.nasa.gov/jscnano/ (Photo courtesy of Dan Colbert, Rice University)
Schematic of Nanotube Structure d2=((n2 + m2 + nm)1/2)0.0783 http://www.pa.msu.edu/~adamsth3/nanotube/properties.html
MWNT Conductance vs. Depth (Go being the conductance quantum 1/13 kohm). http://www.gtri.gatech.edu/res-news/BALANCE.html
Amazingly Flexible Tubes Carbon Nanotubes and Related Structures, Harris, p197
The "…force unravels the tube as a knitter would unravel the sleeve of a sweater." (Yakobson & Smalley, 1997) (Yakobson & Smalley, 1997)
The table below gives a comparison of the magnitude of elastic modulus between substances. Material Modulus (GPa) Diamond 1000 Silicon 107 Iron 196 Low Alloy Steels 200-207 Nylon 3-3.4 Silicon Carbide (SiC) 450 Carbon Nanotubes approx. 630 (Cornell, 1996)
The top picture shows a bent nanotube. The bottom picture shows the same nanotube after release from the matrix. From: Ebbesen (ed.), Carbon Nanotubes: Preparation and Properties, CRC Press, Boca Raton (1997).
Current State of the Research • A Few Working Applications • Polymer Reinforcement • Electron Guns • Scanning Probe Microscope Tips • A Lot of Hype and Theoretical Work • Electronic Circuit Elements • Artificial Nanostructures
Polymer Reinforcement Carbon Nanotubes and Related Structures, Harris, p206
Electron Guns • Nanoscale pointed conductors used as electron field emitters • Sharp Nanotube Points Make Them Ideal as Electron Guns • One application of Electron Guns is in Field Emission Displays • Electrons Emitted from Source Exciting a Phosphor
Nanotube in a Field Emission Display Carbon Nanotubes and Related Structures, Harris, p150
Scanning Probe Microscope Tips • Large, Blunt Conventional Tip Limit Microscope Resolution • Sharp Point of Nanotube Provides for High Resolution Imaging • Used as Tips for Atomic Force Microscopy • Electrical Conductivity Allows for Use In Scanning Tunneling Microscopy
A New Kind of Pencil Carbon Nanotubes and Related Structures, Harris, p 209
Nanotubes as Circuit Elements • Nanotubes Conductivity is Determined by Chirality and Environment • Semiconducting • Conducting • Insulating
Testing A Nanotube For Electrical Properties Carbon Nanotubes and Related Structures, Harris, p 128
Nanotube Field Effect Transistor • Semiconducting SWNT Placed Between Two Electrodes • Appling Voltage To Gate Electrode Changes SWNT from Conducting the Insulating Carbon Nanotubes and Related Structures, Harris, p133
Nanostructures Looks Cool. Can We Build It? Carbon Nanotubes and Related Structures, Harris, p 268
In Conclusion • Nanoscale Tubes Made From Carbon Hexagons • Exceptional Physical Properties • Semiconducting, Conducting or Insulating • High Strength • Field of Research is Only 9 Years Old • Best and Most Innovative is Yet to Come