Vertically aligned carbon nanotubes: Synthesis and atomic oxygen functionalization

In this work, a controlled synthesis route for obtaining highly vertically aligned CNTs is reported. This route is based on the combination of the magnetron sputtering deposition to prepare the catalysts and the chemical vapour deposition (CVD) technique to synthesize the CNTs. The oxygen functionalization of the vertically aligned multi-walled carbon nanotubes (v-CNTs) was studied, aiming at determining the nature of the functional groups grafted at the tip of the CNTs. The functionalization was performed through exposure of v-CNTs to atomic oxygen generated in a micro-wave plasma. The vertical alignment of the CNTs was characterized before and after the functionalization treatment using scanning electron microscopy. Static contact angle measurements and x-ray photoelectron spectroscopy analyses were used to investigate changes induced at the tips of the CNTs due to functionalization.