Growth Process of Vertically Aligned Single-walled Carbon Nanotubes
نویسندگان
چکیده
The growth process of vertically aligned single-walled carbon nanotube (SWNT) films was investigated by means of in situ optical analysis and scanning electron microscopy. The measurements reveal that the growth of the SWNT film decreases after longer reaction times. This decrease is attributed to a combination of a diminishing growth rate and burning of the SWNTs due to oxygen in the growth chamber. Using an observed correlation between the optical absorbance of SWNT films and the film thickness, the general behavior of the SWNT film growth process was determined. It was found that burning of the SWNT film could be suppressed by enhancing the quality of the chamber vacuum seal, which also lead to thicker film growth. However, the exponential decrease in catalyst activity has not been circumvented at present. Methods of sustaining the catalyst activity must be developed in order to realize large-scale production of vertically aligned SWNT films.
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