The name is absent

19

Using the above procedure, the next step was to optimize the growth
parameters. Despite the fact that this particular furnace was the one used to grow
the DWNTs in reference [37], it had since been moved and had been reassembled
with the new MFCs. Again, due to the sensitivity of the growth process, any small
change in the growth environment may produce a large change in the success of the
synthesis. As observed in the early growth runs, it was determined that the
bubbling flow rate had the most significant effect on the success of the synthesis as
compared to the temperature and flow rates of the other gases, and should be the
main focus of the optimization work. Basing off of the previously successful growth
parameters and the observations from the tests stated above, the parameters in
Table 2.1 (with the obvious exception of Qb) were selected to optimize this
parameter; a series of growth runs with various flow rates through the water
bubbler were conducted, and the resulting heights of the growths (as measured by
SEM) were compared. In Figure 2.4, we can see that from 0 - 125 seem of flow
through the bubbler, ~85 seem appears to be the flow rate by which to pick up the
optimum amount of water vapor to promote the tallest growth given the other
parameters. With these parameters, growths up to 2.5 mm in-length were achieved
with consistent repeatability.

2.1.3. A-CNTs Grown Via Pre-Deposited Catalyst CVD

By using the previously-mentioned parameters, I was able to synthesize
even, regular mats of aligned CNTs with fairly high repeatability. Examples can be

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