Surface-enhanced Raman scattering from small numbers of purified and oxidised single-walled carbon nanotubes

Surface enhanced resonance Raman scattering (SERRS) has been applied to investigate defects in purified and carboxylated single-walled carbon nanotubes (SWCNTs). For both samples SERRS spectra with temporal fluctuating peak intensities and positions in the range of 1000–1350 cm−1 have been observed. A series of peaks in this window coincide with peak positions that have been assigned to arise from Stone–Thrower–Wales and heptagonal–pentagonal intramolecular junction defects on the nanotubes surface. The role of possible amorphous carbon impurities is also discussed.