Influences of hydrocarbon radicals on the growth of Carbon nanotubes using heated-nozzle chemical vapour deposition

In this paper, the synthesis of carbon nanotubes (CNTs) on different substrates (i.e. Cu, Cr, Ta, Au, Ti, and Si) was performed using heated nozzle chemical vapour deposition (HN-CVD). The diffusion of high-order hydrocarbon radicals, i.e. CaHb (where a = 5, 6, and 7) generated through the heated nozzle (800-850 °C) via pyrolysis (they were verified by in-situ mass spectroscopy), which is placed a few centimeters above the substrate, plays an important role in CNT growth. Thus, the growth of CNTs deposited on the substrates, which were unavailable in thermal chemical vapour deposition (T-CVD) (540-600 °C), could be correlated to these precursors.