We have investigated the effects of chemical treatment on Single Wall Carbon Nanotube (SWCNT) before and after being modified with HNO<sub>3</sub>/H<sub>2</sub>SO<sub>4</sub> by Raman, FTIR and UV-Vis-NIR spectroscopy. The results show successful carboxylation of the CNT sidewalls as observed from FTIR and UV-Vis-NIR spectroscopy. This successful functionalization is achieved in 6-8 hrs of refluxing. We also report changes in the first and second order Raman spectra of SWNTs functionalized with oxygenated groups. During the experiment, we observe some important Raman features: Radial breathing mode (RBM), Tangential mode (G-band), and Disordered mode (D-band); which are affected due to the chemical oxidation of carbon nanotubes. We found that the ratio of D- to the G-band intensity (I<sub>d</sub>/I<sub>g</sub>), increase after functionalization and the RBM mode in acid treated SWCNTs is almost disappeared.
KeywordsSingle Wall Carbon NanotubesFunctionalizationRaman SpectroscopyFtir and Uv-Vis-Nir Spectroscopy
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