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arXiv · 1010.4714

Double resonance Raman study of disorder in CVD-grown single-walled carbon nanotubes

Rahul Rao·Jason Reppert·Xianfeng Zhang·Ramakrishna Podila·Apparao M. Rao·Saikat Talapatra·Benji Maruyama
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Abstract

Single-walled carbon nanotubes (SWNTs) with varying degrees of disorder were investigated using multiple-excitation Raman spectroscopy. The lattice disorder was imparted into the nanotubes by the addition of varying amounts of sulfur to the iron catalyst in a thermal chemical vapor deposition process. Changes in the intensities of peaks occurring due to a double resonance Raman process were studied. The intensity of the disorder-induced D band increased with a decrease in the sulfur content. Upon post-synthesis heat treatment, the double resonance process got quenched due to defect healing. The second order G' band and iTOLA bands exhibited a two-peak structure, of which one of the peaks is relatively more sensitive to defects and decreased in intensity with heat treatment.

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Rahul Rao, Jason Reppert, Xianfeng Zhang, Ramakrishna Podila, Apparao M. Rao, Saikat Talapatra, Benji Maruyama. 2010-10-22. Double resonance Raman study of disorder in CVD-grown single-walled carbon nanotubes. https://arxiv.org/abs/1010.4714

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