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arXiv · cond-mat/0701359

Raman frequency shift in oxygen functionalized carbon nanotubes

Z. X. Guo·J. W. Ding·Y. Xiao·D. Y. Xing
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Abstract

In terms of lattice dynamics theory, we study the vibrational properties of the oxygen-functionalized single wall carbon nanotubes (O-SWCNs). Due to the C-O and O-O interactions, many degenerate phonon modes are split and even some new phonon modes are obtained, different from the bare SWCNs. A distinct Raman shift is found in both the radial breathing mode and G modes, depending not only on the tube diameter and chirality but also on oxygen coverage and adsorption configurations. With the oxygen coverage increasing, interesting, a nonmonotonic up- and down-shift is observed in G modes, which is contributed to the competition between the bond expansion and contraction, there coexisting in the functionalized carbon nanotube.

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Z. X. Guo, J. W. Ding, Y. Xiao, D. Y. Xing. 2007-01-18. Raman frequency shift in oxygen functionalized carbon nanotubes. https://doi.org/10.1088/0957-4484%2F18%2F46%2F465706

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