Details

Autor(en) / Beteiligte

• Laudenbach, Jan
• Schmid, Daniel
• Herziger, Felix
• Hennrich, Frank
• Kappes, Manfred
• Muoth, Matthias
• Haluska, Miroslav
• Hof, Ferdinand
• Backes, Claudia
• Hauke, Frank
• Hirsch, Andreas
• Maultzsch, Janina

Titel

Diameter dependence of the defect-induced Raman modes in functionalized carbon nanotubes

Ist Teil von

• Carbon (New York), 2017-02, Vol.112, p.1-7

Ort / Verlag

Elsevier Ltd

Erscheinungsjahr

2017

Link zum Volltext

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Covalent functionalization of single-walled carbon nanotubes typically leads to an intensity increase of the defect-induced Raman mode (D mode). A large intensity ratio of the D and G modes (D/G ratio) is therefore often used as evidence for a successful functionalization. Here, we discuss the effect of the D-mode resonance on the D/G ratio and compare pristine and covalently functionalized nanotubes. By resonance Raman spectroscopy we study the evolution of the lineshape and frequencies of the D and 2D modes of samples enriched with semiconducting and metallic nanotubes in comparison with the radial breathing mode. First, we experimentally demonstrate the dependence of the D- and 2D-mode frequencies on the tube diameter and derive an analytical expression for both frequencies as a function of the diameter and the optical transition. Furthermore, we demonstrate that the contribution of the D and 2D modes for small SWCNTs disappears in covalently functionalized samples due to partial destruction. In fact, this can change the measured D/G ratio significantly and has a fundamental impact on the determination of the degree of SWCNT functionalization by Raman spectroscopy.