Carbon nanotubes Raman spectroscopy characterization

Raman spectroscopy is very useful for a correct carbon nanotube characterization, when SEM and TEM analyses do not provide univocal results. Eigure 6.29 shows an example of the carbon nanotube Raman analysis. 

Raman spectroscopy has been used to determine various features and characterization of carbon nanotubes, and has been instrumental in determining 1D electronic structure and mechanical strength and compliance of these materials (69, 61). 

X-ray diffractograms for pristine and PEI-wrapped arc-SWCNTs are presented in Figure 10.6. The peak corresponding to SWCNT bundles (appearing at low diffraction angles (43), 20 = 6°) disappear after the purification and wrapping processes. Raman spectroscopy can also be applied to characterize these dispersions. The G/D ratio decreases drastically for the shrouded carbon nanotubes after the wrapping process (see Table 10.1), attributed to an increase in the... 

Single-walled carbon nanotubes (SWNTs) can behave as semiconductors or metals, depending on their chirality. Therefore, vibrational spectroscopy is indispensable for characterizing chemical stmctures. Especially, resonance Raman spectroscopy is ccai-sidered to be one of most powerful tools, which provides us rich information about nanotube diameters or defect densities [10, 27, 39]. However, much more detailed characterization is required for further development of carbon-based nanotechnology. 

Carbon nanotubes and graphite are excellent model systems to address fundamental issues related to physical materials science. This is due to relative simplicity of these materials containing just one type of atoms and small number of vibration bands as well as possibility of variation of the contributions from sp and sp hybrid states of carbon atoms within the same system. Raman spectroscopy is very important and powerful tool for the study and characterization of graphitic materials and carbon nanotubes especially. In this article, we give a short review of the achievements of the Raman spectroscopy in the study of the physical properties of carbon nanotubes during the last decade. 

Jorio A, Saito R, Dresselhauss G, Dresselhaus MS (2004) Determination of nanotube properties by Raman spectroscopy. Phil Trans R Soc Lond A 362 2311-2336 Kobayashi K, Takagi D, Ueno Y, Homma Y (2004) Characterization of carbon nanotubes suspended between nanostructures using micro-Raman spectroscopy. Physica E 24 26-31 Dresselhaus MS, Eklund P (2000) Phonons in carbon naotubes. Adv Phys 49 705-814 Anderson N, Hartschuh A, Novotny L (2007) Chirality changes in carbon nanotubes studied with near-field Raman spectroscopy. Nano Lett 7 577-582... 

Gomez-De Arco L, Lei B, Cronin BS, Zhou C (2008) Resonant micro-Raman spectroscopy of aligned single-walled carbon nanotubes on a-plane sapphire. Appl Phys Lett 93 123112 Jorio A, Pimenta MA, Souza Filho AG, Saito R, Dresselhaus G, Dresselhaus MS (2003) Characterizing carbon nanotube samples with resonance Raman scattering. New J Phys 5 139.1-139.17... 

The characterization of carbon nanotubes usually is carried out using Raman spectroscopy. Nonetheless, the use of FTIR allows the determination of functional groups when carbon... 

Raman spectroscopy is a method of characterization very often used for carbonaceous compounds. In the case of nanotubes, two principal modes are very useful to their characterization (Figure 3.45). The first is the radial breathing mode (RBM) at 150 cm It is characteristic of sp carbons of carbon nanotubes because it corresponds to the vibration of all the carbon... 

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