Ambiguity in the Characterization of Chemically Modified Single-Walled Carbon Nanotubes: A Raman and Ultraviolet−Visible−Near-Infrared Study

Single-walled carbon nanotubes (SWCNTs) sonicated in o-dichlorobenzene and benzyl chloride show anomalous behavior when characterized with a Raman microscope and ultraviolet−visible−near-infrared spectroscopy. SWCNTs treated with the aforementioned solvents lead to a small but distinct increase in the Raman D peak, when irradiated with laser power higher than 0.12 mW/μm2. This can be mistakenly interpreted as covalent functionalization, but we …