Observation of the diameter-dependent Raman dispersion effect in chemically oxidized multiwalled carbon nanotubes

• Published in: The Journal of physics and chemistry of solids Vol. 72; no. 10; pp. 1133 - 1139
• Main Authors: Lee, Szetsen, Peng, Jr-Wei
• Format: Journal Article
• Language: English
• Published: Elsevier Ltd 01.10.2011
• Subjects: A. Nanostructures; C. Raman spectroscopy; Curvature; D. Defects; Defects; Dispersions; Multi wall carbon nanotubes; Nanostructure; Oxidation; Scanning electron microscopy; Trends; C. Raman spectroscopy; D. Defects; A. Nanostructures
• ISSN: 0022-3697; 1879-2553
• DOI: 10.1016/j.jpcs.2011.07.001

Chemical oxidation of multiwalled carbon nanotubes (MWCNTs) using H 2SO 4/HNO 3 solution has been monitored by micro-Raman spectroscopy and X-ray absorption spectroscopy. The diameter distribution variation in MWCNTs due to chemical oxidation has been measured by scanning electron microscopy and transmission electron microscopy. The Raman dispersion behaviors of the intensity ratio and the band positions of the D, G, and G′ bands were found to be correlated with the MWCNT diameter distribution. It was also found that, during the nanotube unzipping process, defect formation complicates the observation of the diameter-dependent Raman dispersion effect. The curvature effect plays an important role in the intensity ratio trend. On the other hand, defect formation dominates the band position trend. ► The curvature effect plays an important role in the intensity ratio trend. ► Defect formation dominates the band position trend. ► Defect formation complicates the diameter-dependent Raman dispersion effect.