The chirality-dependent combustion of single-walled carbon nanotubes (SWCNTs) during oxidation in both
air and hydrogen peroxide was investigated using photoluminescence and Raman spectroscopy. Under air
oxidation conditions, SWCNTs with a higher chiral angle and smaller diameter were observed to decompose
more rapidly. The decomposition rate of each chiral index was determined from the reaction rate analysis,
and it was found that the reaction is governed by a “local curvature radius” along the C−C bond. The reaction
barriers for breaking the C−C bonds after cycloaddition with oxygen molecules were obtained for 10 types
of SWCNTs using first-principles calculations. The barrier heights were found to depend on the local curvature
radius, which showed good agreement with the experimental results. On the other hand, for the oxidation
reaction in hydrogen peroxide, oxygen radicals decomposed the smaller-radius SWCNTs more rapidly without
any chirality selection. As a result, two different chirality distributions for SWCNTs with similar diameters
were obtained by these oxidation processes.