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Growth of oriented carbon nanotubes on quartz substrates and transfer on other substrats
Auteur(s): Jourdain V.
(Affiches/Poster)
GDR Nanotubes (19/10/-23/10/2009) (Coma Ruga, ES), 2009-10-19 |
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Self-Deactivation of Single-Walled Carbon Nanotube Growth Studied by in Situ Raman Measurements
Auteur(s): Picher Matthieu, Anglaret E., Arenal Raul, Jourdain V.
(Article) Publié:
Nano Letters, vol. 9 p.542-547 (2009)
Ref HAL: hal-00511037_v1
PMID 19159251
DOI: 10.1021/nl802661z
WoS: 000263298700007
Exporter : BibTex | endNote
81 Citations
Résumé: In situ Raman measurements were used to investigate the kinetics and the self-deactivation of the growth of single-walled carbon nanotubes during catalytic chemical vapor deposition. The kinetics appear controlled by the mass-transport of the gaseous precursor at low precursor pressure and high temperature and by the catalytic decomposition of the precursor at high precursor pressure and low temperature. The initial growth rate and the lifetime display inversely correlated evolutions with the growth parameters. In addition, we measured the activation energy for the healing of defects during the growth and discuss it in comparison to the apparent activation energies measured for the initial growth rate and the lifetime. Our results support that the healing of the edge defects controls both the crystalline order and the growth lifetime.
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Substrate preparation techniques for direct investigation by TEM of single wall carbon nanotubes grown by chemical vapor deposition
Auteur(s): Fiawoo M. -F., Bonnot A. -M., Jourdain V., Michel T., Picher Matthieu, Arenal R., Thibault-Penisson J., Loiseau A.
(Article) Publié:
Surface Science, vol. 603 p.1115-1120 (2009)
Texte intégral en Openaccess :
Ref HAL: hal-00511036_v1
DOI: 10.1016/j.susc.2009.02.029
WoS: 000265730300008
Exporter : BibTex | endNote
7 Citations
Résumé: We have investigated and evaluated different TEM sample preparation techniques for studying carbon single-walled nanotube (C-SWNT) nucleation and growth, issued from CVD processes when the catalyst is supported on a substrate. This kind of study requires means to observe individual and isolated tubes. It implies using synthesis conditions able to produce only a low density of tubes and to thin the substrate to electron transparency, to observe the nanotubes and the catalytic particles from which they have grown in their native state. We have tested two approaches, depending if the substrate is thinned after or before the synthesis. The low tube density requirement led us to exclude all the techniques where the substrate is thinned to electron transparency after the synthesis. We have shown, that, with this last approach, all TEM preparation techniques dramatically suffer from a lack of control of thin areas with respect to the location of the tubes, which is unknown. However we have demonstrated that the suitable approach is to perform synthesis directly on transparent substrates presenting several holes. We have tested the capabilities and the potentialities of these supports for studying the size distribution and composition of the catalytic particles, the nucleation mode, the diameter and helicity of the tubes. These results are very promising and represent an important step for performing specific nanoscale TEM analyses necessary for the study of the growth mechanism of nanotubes on substrates. (C) 2009 Elsevier B.V. All rights reserved.
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Indexing of individual single-walled carbon nanotubes from Raman spectroscopy
Auteur(s): Michel T., Paillet M., Nakabayashi D., Picher Matthieu, Jourdain V., Meyer J. C., Zahab A. A., Sauvajol J.-L.
(Article) Publié:
Physical Review B, vol. 80 p.245416 (2009)
Ref HAL: hal-00496809_v1
DOI: 10.1103/PhysRevB.80.245416
WoS: 000273229200120
Exporter : BibTex | endNote
50 Citations
Résumé: From combined Raman spectroscopy and electron diffraction studies on several freestanding single-walled carbon nanotubes (SWNTs), we define Raman criteria which correlate the main features of the Raman spectrum (radial breathing mode and G modes) and the optical transition energies with the structure of the SWNT under investigation. On this basis, we discuss the possibilities to determine the (n,m) indices of an individual SWNT from a single wavelength Raman experiment. We show the efficiency of this approach in assigning the (n,m) structure of different individual nanotubes including all types of achiral SWNTs. Finally, the limits and the accuracy of the method are discussed.
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Mécanisme de croissance des nanotubes de carbone suivi par spectroscopie Raman in situ
Auteur(s): Jourdain V.
(Séminaires)
, 2009-01-19 |
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Temperature dependence and pressure dependence of the vibrational properties of corannulene
Auteur(s): Alvarez L., Le Parc R., Jourdain V., Dennler S., Bantignies J.-L., Sauvajol J.-L., Rose Jonathan A., Scott Lawrence T.
(Article) Publié:
Physica Status Solidi B, vol. 245 p.2261-2263 (2008)
Texte intégral en Openaccess :
Ref HAL: hal-00496491_v1
DOI: 10.1002/pssb.200879611
WoS: 000260581800086
Exporter : BibTex | endNote
4 Citations
Résumé: Herein, we report the experimental investigation of the vibrational properties of corannulene using Raman spectroscopy. The temperature dependences of the Raman spectra between 300 and 20 K reveal a very high sensitivity of the low frequency domain between 40 and 200 cm(-1) compared to the intramolecular domain. The behavior of the Raman modes of the corannulene under pressure, between 0.53 GPa and 8 GPa, is also studied. Under pressure, in the intermolecular vibrational domain (<150 cm(-1)), two transitions occur suggesting metastable intermediate stages under pressure. (C) 2008 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim
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Mechanisms of SWCNT growth and deactivation from in situ Raman measurements
Auteur(s): Jourdain V.
Conference: MRS Fall Meeting 08 (Boston, United States of America, FR, 2008-12-01)
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