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Adsorption on Carbon Nanotubes Studied Using Polarization-Modulated Infrared Reflection−Absorption Spectroscopy

“…Applying these results to the present data then suggests a model in which H reacts preferentially 55,56 at or near defective or strained sites, causing a reduction in intensity in the 1300 cm -1 mode, as well as a loss of some >CdC< sites (1580 cm -1 ), to produce alkyl-like s(CH 2 ) n CH 3 or sC(H 2 )sC(H 2 )s species. Such a process implies an opening of holes in the nanotube wall.…”

“…If the 1300 cm -1 peak is, in fact, associated with strain or defects of some kind, then the data are consistent with these being reactive sites. The elimination of the Raman D-band by thermal oxidation has been reported, 54 and previous theoretical work 55,56 indicates that adsorption of H should be enhanced near regions of strain in nanotube walls. In the region between the negative 1300 and 1580 cm -1 peaks, there is a suggestion of a positive peak at about 1450 cm -1 , the expected energy of a CsH bending mode.…”

Encapsulation and convex‐face thiozonolysis of triatomic sulfur (S3) with carbon nanotubes

“…Although nanotubes have not yet been used to encapsulate sulfur allotropes such as thiozone, literature nanotube calculations have revealed convex‐surface diameter‐dependent reactions with higher reactivity for the lower radii nanotubes . For example, density functional theory (DFT) calculations on singlet oxygen with ( n ,0) zigzag SWNTs showed an increased exothermicity with nanotubes of reduced diameters, and that type (metallic, chiral, non‐metallic) did not play a role in this diameter–reactivity relationship .…”

“…Recent DFT calculations using GGA‐PW91/DNP to model the addition of methylamine to C 60 , C 50 , (5,5) SWNT, and (10,10) SWNT revealed a similar curvature dependence, although the addition of benzenediazonium salts to SWNTs was controlled by the optical band gap of the tube rather than the pyramidalization of the carbon atoms . DFT (ONIOM) methods have showed that the 1,3‐dipolar cycloadditions of formoazomethine ylide and fulminic acid took place only on the smallest‐diameter SWNTs …”

Indices of the fullerenes reactivity

“…48 Reactions of radicals H• and СН 3 • addition to the cap of (10,10) nanotube have been studied by molecular dynamics with Brenner potential and the linear dependence between heats of reactions and pyramidality angles has been found. 50 It has been also noted that reaction sites whose populations are higher than the average value of population, are characterized with the higher values of θ P . Role of the curvature and pyramidality angles for estimation of reactivity and stability not only of fullerenes but another framework nanostructures based on the metal oxides has been considered.…”