(a)
(b)
(c)
Figure 3: (a) Raman spectra of SWNTs grown on the Co/MgO catalyst acquired at different temperatures. (b) The G mode frequency plots against temperature. (c) The G mode of SWNTs under 3 mW/μm2 demonstrating an ~7.6 cm-1 redshift compared with Raman spectra acquired at room temperature.