Low temperature growth of carbon nanotubes from methane catalytic decomposition over nickel supported on a zeolite.

Multi-walled carbon nanotubes from 8 to 63 nm in diameter and from 60 to 413 nm in length, were synthesized over nickel supported on a zeolite by the chemical vapor deposition of methane in the relatively low temperature range 400-550 degrees C. The carbon deposited was analyzed by x-ray powder diffraction, Raman spectroscopy, and scanning and transmission electron microscopy. The effects of the reaction temperature on the carbon nanotube formation and relative purity were evaluated.