The rapid progress of interest in carbon nanotubes research started with a development of sensitive tools for their observation and characterization. Raman spectroscopy and atomic force microscopy (AFM) has been successfully applied for studying carbon nanotubes length and diameter, electronic type (metallic or semiconducting), and whether nanotubes are separated or in bundle. Due to the specific combination of strong van Hove singularities of the phonon density of states and Raman resonance effects it is possible to measure Raman scattering spectra of small bundle of carbon nanotubes or even of single nanotube. Recent progress in understanding of the Raman spectra of relatively simple single wall carbon nanotubes (SWNT) stimulate the further Raman studies of more complicated multiwall carbon nanotubes (MWNT). We present the preliminary results of Raman scattering measurements of multiwall carbon nanotubes. The studied nanotubes have been grown by electric arc method and chemical vapor deposition (CVD) method. The nanotubes have been carefully dissolved, separated and then characterized by AFM. The micro-Raman spectra of the objects are taken with different wavelength excitations and in the temperature range 4K - 300K. Basically the spectra are quite similar to the well known single wall carbon nanotube spectra. The major Raman bands of single wall nanotubes are found in the spectra. In particular the disorder effects are visible due to the pronounced D band at ~1350 cm-1. Metallic and semiconducting type of conductitivity is distinguished through an analysis of the G (LO) mode at ~1600 cm-1. All the results will be discussed and compared with the literature results.

• Legal notice:
  

  Copyright (c) Pielaszek Research, all rights reserved.
  The above materials, including auxiliary resources, are subject to Publisher's copyright and the Author(s) intellectual rights. Without limiting Author(s) rights under respective Copyright Transfer Agreement, no part of the above documents may be reproduced without the express written permission of Pielaszek Research, the Publisher. Express permission from the Author(s) is required to use the above materials for academic purposes, such as lectures or scientific presentations.
  In every case, proper references including Author(s) name(s) and URL of this webpage: https://science24.com/paper/982 must be provided.

1. Synthesis of gallium nitride nanowires by Sublimation Sandwich Method
2. Synthesis of aluminum nitride nanopowder; compare methods for determination of the grain size in nanopowders 
3. Resonance Raman scattering and lattice dynamics of GaMnN crystals
4. Lattice dynamics and Raman spectroscopy of ZnO:Mn crystals
5. Light polarized resonant Raman spectra from individual carbon nanotubes
6. Microscopy and spectroscopy techniques in characterization of thick GaN and Ga_1-xMn_xN layers grown by Sublimation Sandwich Method
7. Single crystals of gallium nitride doped with gadolinium- synthesis and properties.
8. Self-organized microstructure of TiO₂-MnO
9. Magnetic Encapsulates: Nd-Fe-B@C and Fe@C for drug delivery systems.
10. Close-Spaced Crystal Growth and Characterization of BP Crystals
11. GaN growth by Sublimation Sandwich Method
12. Magnetotransport studies of Ga(Mn,Fe)N bulk crystals