Studies of Multiwall Carbon Nanotubes using Raman Spectroscopy and Atomic Force Microscopy

摘要

Preliminary results of Raman scattering measurements of multiwall carbon nanotubes (MWCNT) are presented. The nanotubes have been carefully dissolved, separated and then characterized by AFM. The micro-Raman spectra are taken with 514,5nm wavelength excitations in the range 4K-400K. Basically the spectra are quite similar to the well known single wall carbon nanotube spectra, but the low frequency band is absent. The major Raman bands, observed in single wall nanotubes are found in the spectra. In particular the disorder effects are visible due to the pronounced D band at ～1350cm{sup}(-1). Metallic and semiconducting type of conductivity is distinguished through analysis of the G (LO) mode at ～1600cm{sup}(-1). A new feature in these spectra exists at ～843cm{sup}(-1). Low energy radial breathing mode absence has been explained.