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Abstract: This paper is dedicated to carbon nanotubes grown by electron cyclotron resonance plasma-enhanced chemical vapour deposition. It has been shown that carbon nanotubes (CNTs) can be grown at temperature as low as 550 °C by this technique. X-ray photoelectron spectroscopy and near-edge X-ray absorption fine structure spectroscopy were used to analyse nitrogen-doped CNTs. Independently of the synthesis temperature, about 4 at.% nitrogen are incorporated in the CNTs. A good correlation was found between XPS and NEXAFS results. Four components (397.3, 398.5, 400.8 and 402.5 eV) compose N 1s XPS spectra related to different chemical environments of nitrogen. This interpretation can be used as a simple check method of the presence of CNTs on as-deposited PECVD samples. [Copyright &y& Elsevier]

Abstract: This paper reviews the on-going design, R&D and procurement activities, mostly conducted within the ITER framework, on-going in Europe under the co-ordination of Fusion for Energy (F4E), in co-operation with the European Fusion Associations and aimed at the establishment of the ITER Heating Neutral Beam (HNB) system. [Copyright &y& Elsevier]

This work presents the changes induced at the nanometer scale by the nitrogen incorporation into amorphous carbon nitride a-CNx films deposited by radio-frequency (r.f.) magnetron sputtering. High N content films (20 to 33 at.%) have been analysed by electron energy loss spectroscopy (EELS) and by near edge X-ray absorption fine structure (NEXAFS). EELS spectra at C K and N K edges roughly indicate the increase of the corresponding π* features, associated to N sp2 and C sp2 bonds, vs. the N content. Fine structures of the π* region of the N K edge spectra show at least three contributions, with different evolution depending on the N content. The discrepancies between the results recorded by these two techniques are only outward and they can be explained by the influence of the plasma parameters (pressure lying from 0.5 to 13 Pa and various Ar/N2 mixtures) on the deposition process. All the results are in good agreement with the XPS analysis of the N 1s data. [Copyright &y& Elsevier]