The name is absent

3

produce and still exhibit impressive properties as compared to many other
materials. The work presented herein is based upon such CNTs, as produced
through chemical vapor deposition (CVD).

1.2. Techniques in Carbon Nanotube Synthesis

Over the course of the 1990's, several novel synthesis methods were devised,
and most of those techniques have been refined over the past decade and are still in
use today to produce CNTs for specific research, industrial, and commercial needs.
As described previously, CNTs come in many varieties. Each of these synthesis
methods produces its own "fingerprint” of CNTs, which is typically a distribution of
certain CNT types and sizes. For specific applications, the synthesis technique is
typically selected by the quantity, quality, and size∕chirality of the desired material.
Below, I summarize the major milestones in CNT synthesis, and delineate each
technique's successes and shortcomings.

1.2.1. Early Carbon Nanotube Synthesis Methods

Arc-Discharge was the first technique used to deliberately produce CNTs, as
reported by Iijima in 1991 [1]. The yield of CNTs by this process was quite low,
though they are typically of very high crystallinity. A few years later, Ebbeson &
Ajayan expanded upon the arc-discharge method to produce gram quantities of
these CNTs [12], which include both SWNTs and MWNTs with lengths of up to 50
μm. By their method, ~ 18 V (AC or DC) is applied across two graphitic rods in a
500 Torr helium atmosphere. When the two electrodes are brought close enough to

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