Temperature coefficients of raman frequency of individual single-walled carbon nanotubes

Abstract

In the present study, individual suspended single-walled carbon nanotubes (SWNTs) were prepared and the temperature coefficients of Raman frequency of 13 SWNTs were measured. It is found that the temperature coefficients of the G-band frequency (αωG) are similar, around (-1.67± 0.20)×10-5/K, whereas in the case of the radial breathing mode (RBM), the coefficients (αωRBM) are varied from a minimum value of -1.06 × 10-6/K to a maximum of -2.30 × 10 -4/K. Larger-diameter nanotubes tend to have larger αωRBM values; moreover, nanotubes with similar diameters may show different αωRBM values. These results reveal that the αωRBM value of individual SWNTs depends on both diameter and chirality. © 2007 American Chemical Society.