Epoxidation and deoxygenation of single-walled carbon nanotubes: quantification of epoxide defects.
Epoxidation of single-walled carbon nanotubes (SWNTs) may be carried out by the reaction of SWNTs with either trifluorodimethyldioxirane or 3-chloroperoxybenzoic acid; the resulting O-SWNTs are spectroscopically similar to those formed by ozonolysis. Quantification of the epoxide substituents is possible through the catalytic de-epoxidation reaction using MeReO3/PPh3 and the 31P NMR spectroscopy. The de-epoxidation methodology may be used to determine that wet air oxidation is preferable to either acid or O2/SF6 purification. We have demonstrated that previously assumed "pure" SWNTs are actually "doped" to a level of at least 1 oxygen per 250 carbon atoms.
Ogrin
Douglas
D
Department of Chemistry and Richard E. Smalley Institute for Nanoscale Science and Technology, Rice University, Houston, Texas 77005, USA.
Chattopadhyay
Jayanta
J
Sadana
Anil K
AK
Billups
W Edward
WE
Barron
Andrew R
AR