We have chemically grafted methyoxyphenol functions on the surfaces of electric-arc and HiPco synthesized single-walled carbon nanotubes [1, 2]. To characterise the efficiency of this functionalisation, the materials have been examined via spectroscopic techniques, notably using Raman spectroscopy at five laser excitation wavelengths (457, 488, 514, 532 and 632 nm). The work presented here focuses on the analysis of the radial breathing mode band between 150 and 300 cm-1. Clear evidence is put forward showing that in a heterogeneous, sample, consisting of nanotube bundles, those tubes which are preferentially functionalised are the smaller diameter semiconducting tubes and the metallic tubes. We also address the issue of stability of the metallic nanotubes under laser irradiation. It was experimentally observed that the metallic component in the nanotube bundles exhibits progressive degradation when laser power density exceeds 8 kW/cm2.
[1] J. Liu, Rodriguez I. Zubiri, M. Dossot, B. Vigolo, R.H.Hauge, Y. Fort, J.-J. Ehrhardt, E. McRae. Chem. Phys. Lett. 2006, 430, 93.
[2] J. Liu, Rodriguez I. Zubiri, B. Vigolo, M. Dossot, Y. Fort, J.-J. Ehrhardt, E. McRae. Carbon in press. |