Aligned carbon nanotubes were irradiated in the longitudinal and perpendicular directions, with low-energy carbon and helium ions in order to observe the formation of defects in the atomic structure. Analysis using Raman spectroscopy and scanning electron microscopy indicated bundle rupture and ion track formation on nanotube bundles. Aligned carbon nanotube presented a kind of defect comprising ravine formation and tube agglomeration on top of the substrate. The latter structure was possibly caused by static charge accumulation induced by the incoming ions. Fluence played a role in the short-range order. Higher-fluence irradiation transformed carbon nanotubes into amorphous carbon nanowires.

Agglomeration Defects on Irradiated Carbon Nanotubes. C.S.Moura, N.M.Balzaretti, L.Amaral, R.G.Lacerda, M.A.Pimenta: AIP Advances, 2012, 2[1], 012174