Analysis of the reactivity and selectivity of fullerene dimerization reactions at the atomic level

Nanotube Research Centre, National Institute of Advanced Industrial Science and Technology, Tsukuba 305-8565 Japan.
Nature Chemistry (Impact Factor: 25.33). 02/2010; 2(2):117-24. DOI: 10.1038/nchem.482
Source: PubMed


High-resolution transmission electron microscopy has proved useful for its ability to provide time-resolved images of small molecules and their movements. One of the next challenges in this area is to visualize chemical reactions by monitoring time-dependent changes in the atomic positions of reacting molecules. Such images may provide information that is not available with other experimental methods. Here we report a study on bimolecular reactions of fullerene and metallofullerene molecules inside carbon nanotubes as a function of electron dose. Images of how the fullerenes move during the dimerization process reveal the specific orientations in which two molecules interact, as well as how bond reorganization occurs after their initial contact. Studies on the concentration, specimen temperature, effect of catalyst and accelerating voltage indicate that the reactions can be imaged under a variety of conditions.

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Available from: Toshiya Okazaki, Jul 19, 2015
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    • "At this stage, it should be also noted that the spherical shape of C 60 is retained, even after a long exposure time exceeding 200 s and under 120 kV of the electron beam operation conditions. Moreover, the isolated state of the fullerene cages outside CNHs seems to prevent serious structural changes, in sharp contrast with peapod structures in which fullerenes tightly packed inside nanotubes, easily coalesce with their neighbors under otherwise similar observation conditions [30] [31]. In addition, the stable and robust covalent bonding between the organic Fig. 3 – Representative TEM images of spherical aggregates of (a) intact, (b and c) ammonium-functionalized CNHs 1, and (d–f) C 60 conjugated onto pre-modified CNH-based hybrid material 3. Scale bar is 50 nm. "
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    • "We believe that the most promising method is high-resolution transmission electron microscopy. This method was used for visualizing dynamics of processes inside nanotubes, such as reactions of fullerene dimerization with monitoring of time-dependent changes in the atomic positions [41] and rotation of fullerene chains [42]. The rotational dynamics of C60 fullerenes inside carbon nanotube was studied also by analysing the intermediate frequency mode lattice vibrations using near-infrared Raman spectroscopy [43]. "
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