ABSTRACT Vertically aligned carbon nanotubes (VACNTs) array with high density have been synthesized from a mixture of ferrocene and ethanol using ultrasonic nebulizer techniques. Using scanning electron microscopy (SEM) and transmission electron microscopy (TEM) as well as Raman spectroscopy, investigations reveal that the vertically aligned CNTs are multi-wall CNTs with well-ordered graphene sheets and are about 20 - 50 nm in diameter. We found that high density vertically aligned CNTs can be synthesized at 750℃ - 850℃ and that the length and density of vertically aligned CNTs increase with increasing growth temperatures. In addition, the single-walls CNTs have well-ordered graphene sheet and are about 2 nm in diameter on silicon substrates at 650℃.
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