Cover Picture

Abstract

The cover picture shows a single‐walled carbon nanotube (SWNT) functionalized with nucleophilic carbenes at the sidewall. Normally, single‐walled nanotubes exist in the form of insoluble bundles. The sidewall addition of reactive organic groups such as radicals, nitrenes, or carbenes such as the ones shown in the cover picture disrupts the bundles. The background of the picture shows a typical AFM image of such derivatized SWNTs. The isolated SWNTs are soluble in organic solvents giving black solutions. This enables a spectroscopic characterization of nanotubes in solution. With this versatile sidewall functionalization the decisive requirements for the development of technological applications such as the production of ultrathin films or the processing to polymer composites with new electronic and mechanic properties have been compiled. Details about this new chemical funtionalization of SWNTs is described by Hirsch et al. on pp. 4002 ff.

Oxygen Radical Functionalization of Boron Nitride Nanosheets

“…44,45 This is explained by effect of the bulk h-BN substrate on the vibration of the B-OH groups relative to the vibrational freedom of unbound molecules. 33 The mode at 789 cm -1 in the spectrum of the OH-BNNSs is consistent with the Raman signature of an aryl-boronic acid and is not reported in Raman spectrum of free boric acid molecules. 39,44 Considering the bonding structure of the h-BN lattice, and that the pseudo-delocalized ring structures may be extended out of the plane of the lattice following B atom functionalization and B-N bond cleavage, this band is assigned to the B-OH functional group.…”

“…Broadening of the peaks is attributed to the a combination of the effect of binding of the molecules to the suspended BNNS substrate, which is known to significantly attenuate the signal and also the inhomogeneity of the environment of the groups to the dislocated lattice at the point of binding. 33 It has been proposed that B-N bonds will break to facilitate the functionalization, consequently it is expected that there is a spread in the environment of the dislocation when the adduct is grafted to the B atoms and the N atom is protonated and dislocated out of the lattice plane, thus yielding the broadened peaks. The two peaks in the spectrum of the TB-BNNSs, in comparison with the single peak for the free TBP molecule, is explained by the conformational change incurred by the TB groups covalently bound to the solid nanosheet substrate.…”

Enviromentaly Friendly Functionalization of Carboxylated Shortend Multi-Wall Nanotubes with Sunset Yellow Dye

“…In spectrum A, the band at around 1527 cm -1 corresponds to the stretching mode of the C =C double bond that forms the framework of the carbon nano tube Sidewall 11 . The peaks at 1704, 3304 cm -1 and 1071 cm -1 apparently corresponds to the stretching modes of the carboxylic acid groups 12 . In spectrum B The carbonyl peak shift to 1739 cm -1 (as compared with 1704 cm-1 in spectrum A) is a result of esther (C =O)OR linkage formation and the peaks at 3304 (OH) is removed.…”

Electronic structure of carbon nanotubes

“…Covalent functionalization of the nanotube sidewalls was only achieved by reaction with very reactive species, such as radicals, carbenes and nitrenes [36]. Otherwise, the non-covalent sidewall functionalization was obtained by adsorption of polycyclic aromatic hydrocarbon groups, which served for anchoring proteins to the nanotubes [37].…”