Packing density control of aligned carbon nanotubes

Abstract

With utilization of the competitive catalytic reactions between carbon deposition on the pore surface of an anodic alumina template and carbon nanotube (CNT) growth by a Co catalyst, the packing density of CNTs was readily controlled over 4 orders of magnitude. It was shown that the packing density of CNTs changes dramatically depending on the diameter and depth of the templates. Estimated densities of CNTs on templates, which have different aspect ratios, are 2-3 x 10(9), 2-3 x 10(7), and 1-2 x 10(5) CNTS/cm(2), respectively.