Raman study of bromine-doped single-walled carbon nanotubes under high pressure

Abstract

Raman results for different single-walled carbon nanotube bundles doped with Br 2 were studied both at ambient pressure and under high pressure up to 6 GPa. Our study indicates that bromine resides in the interstitial channel of nanotube bundles as a form of polymer.

Spectral fingerprinting of structural defects in plasma-treated carbon nanotubes

“…A similar blue shift was observed in nanotubes doped with bromine. 17 Figure 3 also shows the prominent appearance of DЈ around 1617 cm −1 with plasma treatment, a feature barely visible in the pristine tubes. Literature has been somewhat varied and vague when treating any Raman modes of nanotubes appearing from 1600 cm −1 to 1625 cm −1 .…”

“…This is also consistent with the upshift seen in the Raman E 2g mode, as observed for doped nanotubes. 17 Peaks around 285 eV represent carbon bound to hydrogen atom (sp 3 carbon) as well as amorphous carbon, 6,16 but the resolution of our XPS was not sufficient to distinguish these two peaks. The intensity of this peak increases after plasma oxidation, which represents the destruction of the -conjugation followed by formation of sp 3 carbon atoms by functionalization.…”

High‐pressure optical study of bromine‐doped single‐walled carbon nanotube films

“…This can be attributed to the loss of Raman resonance by hole doping with bromine, whereby electrons are transferred from the states of the tubes to the bromine molecules. The two peaks at 158.3 and 239.4 cm are ascribed to the polybromide chains . The peak at 168.8 cm can be attributed to the RBM of the SWCNTs .…”

“…An earlier high-pressure Raman study on Br-SWCNTs showed that most probably bromine as filler molecule occupies preferentially the interstitial channels of the nanotube bundles [8].…”

“…Here, we present a high‐pressure optical spectroscopy study on the mechanical stability of bromine‐doped SWCNTs (Br‐SWCNTs) with different doping levels in comparison with empty SWCNTs. An earlier high‐pressure Raman study on Br‐SWCNTs showed that most probably bromine as filler molecule occupies preferentially the interstitial channels of the nanotube bundles ().…”