Tunable Raman spectroscopy study of CVD and peapod- derived bundled and individual double-wall carbon nanotubes

Citation Villalpando-Paez, F. et al. " Tunable Raman spectroscopy study of CVD and peapod-derived bundled and individual double-wall carbon nanotubes. Article is made available in accordance with the publisher's policy and may be subject to US copyright law. Please refer to the publisher's site for terms of use. The MIT Faculty has made this article openly available. Please share how this access benefits you. Your story matters. We use 40 laser excitation energies to analyze the differences in the Raman spectra from chemical vapor deposition-derived double-wall carbon nanotube ͑CVD-DWNT͒ bundles, fullerene-derived DWNT bundles ͑C 60-DWNTs͒, and individual fullerene-derived DWNTs with inner type-I and type-II semiconducting tubes paired with outer metallic tubes. For the radial breathing mode ͑RBM͒ of SWNTs, an experimental ␻ RBM vs d t relationship of the form ␻ RBM = A / d t + B is obtained for the inner tubes of DWNT bundles where the A and B constants are found to be close to those obtained by elasticity theory when modeling the elastic properties of graphite. A similar change in ␻ RBM is observed for an inner type-II semiconducting ͑6,5͒ tube and a type-I ͑9,1͒ tube when inside various metallic outer tubes. The G-band frequency is observed to upshift when switching the laser resonance from DWNTs with semiconducting inner tubes to DWNTs with metallic inner tubes. Finally, we measure the GЈ feature from C 60-DWNTs and note a downshift in frequency with respect to that of CVD-DWNTs.