The electrochemical behavior of carbon nanotubes containing both intrinsic and extrinsically introduced defects was investigated via the study of bamboo and hollow multi-walled carbon nanotube morphologies. The controlled addition of argon ions was used to vary the charge and type of extrinsic defect. It was deduced from Raman spectroscopy and voltammetry that the electrocatalytic response of hollow carbon nanotubes could be tailored more significantly, compared to bamboo type carbon nanotubes which had innately highly reactive site densities and were less amenable to modification. An in-plane correlation length parameter was used to understand the variation of the defect density as a function of argon ion irradiation. This had implications for the design of nanotube based chemical sensors, facilitated through the introduction of suitable reactive sites.

Defect Engineering of the Electrochemical Characteristics of Carbon Nanotube Varieties. M.A.Hoefer, P.R.Bandaru: Journal of Applied Physics, 2010, 108[3], 034308