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Size and Shape Dependence of Organo-Interconnected Silsesquioxanes through Hydrolysis-Condensation Reaction Conditions: Nanotubes, Spheres and Films
Auteur(s): Bantignies J.-L., Pichon Benoît, Dieudonne-George P., Wong Chi Man Michel, Bied Catherine, Sauvajol J.-L., J. E. Moreau Joël
(Article) Publié:
Advanced Functional Materials, vol. 17 p.2349-2355 (2007)
Texte intégral en Openaccess :
Ref HAL: hal-00179897_v1
DOI: 10.1002/adfm.200600670
WoS: 000250018800013
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31 Citations
Résumé: A tris-silylated urea-based compound, 1,3,5-tris(triethoxysilylpropylureido)benzene has been synthesized. Hybrids materials with different shapes (films, spheres and tubes) are obtained upon base-catalyzed hydrolytic condensation of this compound. A self-templating process is demonstrated using electron microscopy (SEM and TEM) and X-ray diffraction (SAXS and WAXS) techniques. We show the formation of nanometer size hollow tubes according to the size of the self-templating crystalline precursor. The possibility for this self-templating to occur is due to a favored dissolution of the self-assembled molecules of the precursor in a preferential direction parallel to the cross-section of the crystals
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Terahertz spectroscopy of the crystalline alpha-quaterthiophene: A combined experimental and density functional theory study
Auteur(s): Hermet P., Bantignies J.-L., Maurin D., Sauvajol J.-L.
(Article) Publié:
Chemical Physics Letters, vol. 445 p.47-50 (2007)
Ref HAL: hal-00496380_v1
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Résumé: We have investigated the experimental terahertz phonon modes in a model oligothiophene, the alpha-quaterthiophene (LT phase), by using infrared and inelastic neutron scattering spectroscopy in the 10-50 cm(-1) (0.3-1.5 THz) domain. The ability of density functional theory to reproduce the terahertz infrared phonon modes is also reported. In agreement with the calculation, the experimental infrared spectrum at 10 K is dominated by two phonon modes centered at 32 and 46 cm-(1) respectively assigned to an antiphasis translation mode and a libration of rings. (C) 2007 Published by Elsevier B.V.
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Spectroscopic study of nitrogen doping of multi-walled carbon nanotubes
Auteur(s): Enouz-vedrenne Stephane, Bantignies J.-L., Babaa Marie-rose, Alvarez L., Parent P., Le Normand F., Stephan O., Poncharal Philippe, Loiseau A., Doyle B. P.
(Article) Publié:
Journal Of Nanoscience And Nanotechnology, vol. 7 p.3524-3527 (2007)
Ref HAL: hal-00497062_v1
PMID 18330168
DOI: 10.1166/jnn.2007.839
WoS: 000250388600029
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8 Citations
Résumé: Combined spatially resolved electron-energy loss spectroscopy (EELS) and high resolution near-edge X-ray absorption fine structure (NEXAFS) spectroscopy have been used to investigate the nitrogen doping of multi-walled carbon nanotubes (N-MWNT). EELS indicates that most of the tubes are nitrogen-doped. NEXAFS spectroscopy reveals pyridine-like and nitrile N structures. High resolution NEXAFS experiments show that the main nitrogen concentration originates from a high amount of molecular N-2 encapsulated into only a small quantity of tubes.
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NEXAFS study of multi-walled carbon nanotubes functionalization with sulfonated poly(ether ether ketone) chains
Auteur(s): Babaa Marie-rose, Bantignies J.-L., Alvarez L., Parent P., Le Normand F., Gulas M., Mane J. M., Poncharal Philippe, Doyle B. P.
(Article) Publié:
Journal Of Nanoscience And Nanotechnology, vol. 7 p.3463-3467 (2007)
Ref HAL: hal-00497067_v1
PMID 18330158
DOI: 10.1166/jnn.2007.816
WoS: 000250388600019
Exporter : BibTex | endNote
15 Citations
Résumé: Functionalization of multi-walled carbon nanotubes (MWNTs) surface by sulfonated poly (ether ether ketone) SPEEK chains using a direct attachment reaction was investigated. A two step method was performed. MWNTs were oxidized by a nitric acid treatment to generate carboxyl groups on their surface. The grafting reaction of sulfonated groups of SPEEK with carboxyl groups present on the surface of oxidized MWNTs readily proceeds by using hexane diamine as an interlinking molecule. Transmission electron microscopy (TEM) shows that tubes are wrapped by polymer chains. Near edge X-ray absorption fine structure spectroscopy (NEXAFS) at the C K-edge, 0 K-edge, and N K-edge and X-ray photoelectron spectroscopy (XPS) were used to give evidence of covalent functionalization of MWNTs by SPEEK macromolecules.
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Infrared spectroscopy of single-walled carbon nanotubes
Auteur(s): Sbai K., Rahmani A., Chadli H., Bantignies J.-L., Hermet P., Sauvajol J.-L.
(Article) Publié:
The Journal Of Physical Chemistry B, vol. 110 p.12388-12393 (2006)
Texte intégral en Openaccess :
Ref HAL: hal-00514934_v1
PMID 16800564
DOI: 10.1021/jp0574504
WoS: 000238446900028
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48 Citations
Résumé: By using the spectral moments method, we calculate the infrared spectra of chiral and achiral single-walled carbon nanotubes (SWCNTs) of different diameters and lengths. We show that the number of the infrared modes, their frequencies, and intensities depend on the length and chirality of the nanotubes. Furthermore, the dependence of the infrared spectrum as a function of the size of the SWCNT bundle is analyzed. These predictions are useful to interpret the experimental infrared spectra of SWCNTs.
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Raman active phonons of identified semiconducting single walled-carbon nanotubes
Auteur(s): Paillet M., Michel T., Meyer C., Roth S., Popov V., Henrard L., Sauvajol J.-L.
(Article) Publié:
Physical Review Letters, vol. 96 p.257401-1-4 (2006)
Ref HAL: hal-00514936_v1
PMID 16907341
DOI: 10.1103/PhysRevLett.96.257401
WoS: 000238697000053
Exporter : BibTex | endNote
71 Citations
Résumé: The resonant Raman spectra of (n,m) semiconducting single-walled carbon nanotubes, unambiguously identified from their electron diffraction patterns, have been measured. The diameter dependence of the frequency of the tangential modes with A symmetry has been obtained in the diameter range from 1.4 to 2.5 nm. The comparison between the excitation energies and the calculated transition energies allowed us to determine precisely the values of the Es33 and Es44 transition energies. Finally, in the debate concerning the dominant process at the origin of the first-order Raman scattering in single-walled carbon nanotubes (single resonance process or double resonance process), our results are well understood in the framework of a single resonance process.
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Selecte growth of large chiral angle single-walled carbon nanotubes
Auteur(s): Paillet M., Meyer J.C., Michel T., Jourdain V., Poncharal Philippe, Sauvajol J.-L., Cordente N., Amiens C., Chaudret B., Roth S., Zahab A. A.
(Article) Publié:
Diamond And Related Materials, vol. 15 p.1019-1022 (2006)
Ref HAL: hal-00514937_v1
Exporter : BibTex | endNote
Résumé: We have developed a versatile catalyst-assisted chemical vapor deposition (CVD) technique for the synthesis of single-walled carbon nanotubes (SWNTs) from discrete nickel nanoparticles (average diameter of 4.7 ± 1.5 nm). Atomic force microscopy (AFM), transmission electron microscopy (TEM) and electron diffraction are used to characterize these as-grown nanotubes. On a particular sample we found that the SWNTs have an average chiral angle of 25.3°. This result shows that a control of the chiral angle of SWNT with large diameters (mean diameter = 1.75 nm) and with a relatively broad diameter distribution (standard deviation = 0.5 nm) is achievable to a certain extent.
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