an intoduction to carbon nanotubes by: shaun ard physics 672

An Intoduction to Carbon Nanotubes

By: Shaun ArdPhysics 672

Fullerenes Nobel Prize in

Chemistry 1996 (Smalley, Kroto, Curl)

Cage-like structures of Carbon

Composed of honeycomb type lattices of hexagons and pentagons

Important types include “Buckeyball” and Nanotubes

Sussex Fullerene Gallery

Kohlenstoffnanoroehre Animation

Nanotube Discovery Carbon filaments

had long been known, but nanotube discovery credited to S. Iijima in 1991

Discovered by chance during investigation of fullerene production

Y. Ando et al, Growing Carbon Nanotubes, Materials Today, Oct (2004) 22

Nanotube Discovery (MWNT)

S. Iijima, Helical microtubules of graphitic carbon, Nature (London) 354 (1991) 56

Copyright Alain Rochefort Assistant Professor Engineering Physics Department, Nanostructure Group, Center for Research on Computation and its Applications (CERCA).

Nanotube Discovery (SWNT)

S. Iijima et al, Single-shell carbon nanotubes of 1-nm diameter, Nature (London) 363 (1993) 603

D.S. Bethune et al, Cobalt-catalysed growth of carbon nanotubes with single-atomic-layer walls, Nature (London) 363 (1993) 605

Synthesis Enhancement

Laser-Furnace method High quality

SWNTs Diameter control New materials-

“peapods” Allows for study of

formation dynamics

Reprinted from Mater. Today, 7,Y.Ando, X. Zhao,T. Sugai, and M. Kumar,“Growing Carbon Nanotubes,” 22–29, Copyright 2004, with permission from Elsevier.

Synthesis Enhancement cont.

Catalytic Chemical Vapor Deposition Allows for growth

of aligned nanotubes

Use of a variety of substrates or surfaces

Easily scaled up for increased production

Firstnano “EasyTube 3000”

Properties: Foundation

Nanotubes are fully described by their chiral vector

Ch = n â1 + m â2

Important parameters dt = (3/)ac-c(m

2 + mn + n2)1/2

=tan-1(3n/(2m + n)) Grouped according to

Armchair: n=m, =30° Zigzag: n or m=0, =0° Chiral: 0°<30°

A. Maiti, Caron Nanotubes: Band gap engineering with strain, Nature Materials 2 (2003) 440

V. Popov, Carbon nanotubes: properties and applications, Materials Science and Engineering R 43 (2004) 61-102

Properties: Electronic

(5,5) (9,0) (10,0)

V. Popov, Carbon nanotubes: properties and applications, Materials Science and Engineering R 43 (2004) 61-102

1-D band structure calculated from 2-D graphene band structure using “zone folding” scheme

Ekμ= E2D(k*K2/|K2|+μK1)

K1=(-t2b1+ t1b2)/ N

K2=(mb1- nb2)/ N

Properties: Electronic cont. Theory predicts

nanotubes exhibit both metallic and semi-conducting behavior

|n-m| evenly divisible by 3- metallic

All others semi-conducting with a band gap inversely proportional to the tube diameter

T.W. Odomet al, Atomic Structure and Electronic Properties of Single-Walled Nanotubes, Nature (London) 391 (1998) 62

Properties: Mechanical Young’s Modulus

On the order of 1 Tpa (steel ~200 GPa)

No dependence on diameter for MWNTs but strong dependence for SWNTs

J. Salvetat, Elastic Modulus of Ordered and Disordered Multiwalled Carbon Nanotubes, Adv. Mater. 11 (1999) 161

Applications

Nano-Wires

Applications

Tans et al, Room-temperature transistor based on a single carbon nanotube, Nature 393 (1998)

Nano Transistors

Applications

From IPN CNT group

Field Emitters

Applications

MIT/Riccardo Signorelli J. Fischer, Matt Ray/EHP

Charge Storage

Lithium Ion Batteries

Ultra Capacitors

Conclusion

Nano =