ABSTRACT
M. Meyyappan
John Pelesko
Victor Giurgiutiu
Sergey Edward Lyshevski
Nelson Tansu
Ronald Arif
Zhian Jin
Carbon nanotubes (CNTs) were discovered in 1991 [1] by Sumio Iijima of the NEC Corporation. Since then,
research activities exploring their structure, properties, and applications have exploded across the world. Carbon
nanotubes exhibit unique electronic properties and extraordinary mechanical properties, and, hence, have
received attention in nano-electronics, sensors, actuators, field emission devices, high strength composites and a
host of other applications. A detailed discussion on properties, growth, characterization, and application
development can be found in a recent textbook [2]. Here, a brief overview of these subject matters is presented.
Configurationally, a carbon nanotube can be thought of as a two-dimensional graphene sheet rolled up in the
form of a tube. A single-walled carbon nanotube (SWNT) is a tubular shell made of hexagonal rings (in a
sheet) of carbon atoms, with the ends of the shells capped by dome-like half-fullerene molecules. The SWNTs
are classified using a nomenclature (n, m) where n and m are integer indices of two graphene unit lattice
vectors corresponding to the chiral vector of a nanotube (see Figure 4.1) [3]. A multiwalled carbon nanotube
(MWNT) is configurationally a stack of graphene sheets rolled up into concentric cylinders with the ends
either closed with half-fullerenes or left open. Figure 4.2 shows transmission electron microscopy (TEM)
images of a SWNT and a MWNT. The individual SWNTs in Figure 4.2a is about 1 nm in diameter. The
MWNT has a central core with several walls with a spacing close to 0.34 nm between two successive walls
(Figure 4.2b).
