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A highly-ordered 3D covalent fullerene framework.

Minar NK, Hou K, Westermeier C, Döblinger M, Schuster J, Hanusch FC, Nickel B, Ozin GA, Bein T - Angew. Chem. Int. Ed. Engl. (2015)

Bottom Line: A highly-ordered 3D covalent fullerene framework is presented with a structure based on octahedrally functionalized fullerene building blocks in which every fullerene is separated from the next by six functional groups and whose mesoporosity is controlled by cooperative self-assembly with a liquid-crystalline block copolymer.The new fullerene-framework material was obtained in the form of supported films by spin coating the synthesis solution directly on glass or silicon substrates, followed by a heat treatment.We also note that the 3D covalent fullerene framework exhibits a dielectric constant significantly lower than that of the nonporous precursor material.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Center for NanoScience (CeNS), University of Munich (LMU), Butenandtstrasse 5-13, 81377 Munich (Germany).

No MeSH data available.


Related in: MedlinePlus

TEM images of the fullerene-framework film (190 nm thick) thermally treated at 300 °C under N2 for 1 h. a) Cross-section image, viewed along the [100] direction, of the orthorhombic structure with Fmmm symmetry. The lattice planes perpendicular and parallel to the substrate with measured distances of 6.9 and 11 nm can be indexed as (020) and (002), respectively. b) 2D Fourier transform of the TEM image in (a). c) Representation of the orientational relationship of the orthorhombic structure and the substrate viewed along [100]. d) Plan-view image in [010] orientation, showing large, highly ordered domains. The d values of 11 nm and 7.9 nm are in good agreement with the lattice plane distances of (002) and (200), respectively. e) 2D Fourier transform of the largest domain of (d). f) Expanded version (5×) of the TEM image in (d) on the left side.
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fig02: TEM images of the fullerene-framework film (190 nm thick) thermally treated at 300 °C under N2 for 1 h. a) Cross-section image, viewed along the [100] direction, of the orthorhombic structure with Fmmm symmetry. The lattice planes perpendicular and parallel to the substrate with measured distances of 6.9 and 11 nm can be indexed as (020) and (002), respectively. b) 2D Fourier transform of the TEM image in (a). c) Representation of the orientational relationship of the orthorhombic structure and the substrate viewed along [100]. d) Plan-view image in [010] orientation, showing large, highly ordered domains. The d values of 11 nm and 7.9 nm are in good agreement with the lattice plane distances of (002) and (200), respectively. e) 2D Fourier transform of the largest domain of (d). f) Expanded version (5×) of the TEM image in (d) on the left side.

Mentions: Figure 2 shows TEM micrographs of fullerene-framework films after thermal treatment at 300 °C recorded in cross section and plan view, that is, perpendicular to and along the substrate normal, respectively. The cross section (Figure 2 a–c) shows d values of 11.0 nm parallel to the film and 6.8 nm along the film normal, which is in good agreement with the values determined by SAXS. Plan-view images (Figure 2 d–f) show mutually rotated periodic domains extending over large areas in the μm range. The domains show a rectangular lattice with d values of 11.0 nm and 7.9 nm. The ratio of these values (1.39) and the d value along the film normal of 10.4 nm before further treatments indicate an initially cubic structure with space group Im$\bar 3$m and [011] orientation along the substrate normal. Assuming a lattice constant of 15.7 nm, the observed d values viewed along the [011] direction of such a structure are d(0-11)=11.1 nm and d(200)=7.9 nm, which fits well with our TEM observations. Along the film normal, the slight deviation of the value expected for d(011) (10.4 nm instead of 11.1 nm) observed after film synthesis can be explained by a slight uniaxial shrinkage during drying. As a result of the shrinkage after heat treatment, the structure becomes orthorhombic, with space group Fmmm and lattice basis vectors aorh=acub, borh=(bcub+ccub)×S, and corh=ccub-bcub, where S is the shrinkage factor. In the orthorhombic setting, the indexing of the observed lattice planes changes as follows: (0$\bar 1$1)cub becomes (002)orh and (011)cub becomes (020)orh. The relationship of the initial cubic structure and the orthorhombic structure is depicted in Figure S4. Films with the same space groups and orientations with respect to the substrate exist for carbon and metal oxides.[14] The symmetry change of cubic films with Im$\bar 3$m symmetry in [011] orientation along the film normal to orthorhombic Fmmm in [010] orientation is discussed in detail by Falcaro et al.[13a]


A highly-ordered 3D covalent fullerene framework.

Minar NK, Hou K, Westermeier C, Döblinger M, Schuster J, Hanusch FC, Nickel B, Ozin GA, Bein T - Angew. Chem. Int. Ed. Engl. (2015)

TEM images of the fullerene-framework film (190 nm thick) thermally treated at 300 °C under N2 for 1 h. a) Cross-section image, viewed along the [100] direction, of the orthorhombic structure with Fmmm symmetry. The lattice planes perpendicular and parallel to the substrate with measured distances of 6.9 and 11 nm can be indexed as (020) and (002), respectively. b) 2D Fourier transform of the TEM image in (a). c) Representation of the orientational relationship of the orthorhombic structure and the substrate viewed along [100]. d) Plan-view image in [010] orientation, showing large, highly ordered domains. The d values of 11 nm and 7.9 nm are in good agreement with the lattice plane distances of (002) and (200), respectively. e) 2D Fourier transform of the largest domain of (d). f) Expanded version (5×) of the TEM image in (d) on the left side.
© Copyright Policy - open-access
Related In: Results  -  Collection

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Show All Figures
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fig02: TEM images of the fullerene-framework film (190 nm thick) thermally treated at 300 °C under N2 for 1 h. a) Cross-section image, viewed along the [100] direction, of the orthorhombic structure with Fmmm symmetry. The lattice planes perpendicular and parallel to the substrate with measured distances of 6.9 and 11 nm can be indexed as (020) and (002), respectively. b) 2D Fourier transform of the TEM image in (a). c) Representation of the orientational relationship of the orthorhombic structure and the substrate viewed along [100]. d) Plan-view image in [010] orientation, showing large, highly ordered domains. The d values of 11 nm and 7.9 nm are in good agreement with the lattice plane distances of (002) and (200), respectively. e) 2D Fourier transform of the largest domain of (d). f) Expanded version (5×) of the TEM image in (d) on the left side.
Mentions: Figure 2 shows TEM micrographs of fullerene-framework films after thermal treatment at 300 °C recorded in cross section and plan view, that is, perpendicular to and along the substrate normal, respectively. The cross section (Figure 2 a–c) shows d values of 11.0 nm parallel to the film and 6.8 nm along the film normal, which is in good agreement with the values determined by SAXS. Plan-view images (Figure 2 d–f) show mutually rotated periodic domains extending over large areas in the μm range. The domains show a rectangular lattice with d values of 11.0 nm and 7.9 nm. The ratio of these values (1.39) and the d value along the film normal of 10.4 nm before further treatments indicate an initially cubic structure with space group Im$\bar 3$m and [011] orientation along the substrate normal. Assuming a lattice constant of 15.7 nm, the observed d values viewed along the [011] direction of such a structure are d(0-11)=11.1 nm and d(200)=7.9 nm, which fits well with our TEM observations. Along the film normal, the slight deviation of the value expected for d(011) (10.4 nm instead of 11.1 nm) observed after film synthesis can be explained by a slight uniaxial shrinkage during drying. As a result of the shrinkage after heat treatment, the structure becomes orthorhombic, with space group Fmmm and lattice basis vectors aorh=acub, borh=(bcub+ccub)×S, and corh=ccub-bcub, where S is the shrinkage factor. In the orthorhombic setting, the indexing of the observed lattice planes changes as follows: (0$\bar 1$1)cub becomes (002)orh and (011)cub becomes (020)orh. The relationship of the initial cubic structure and the orthorhombic structure is depicted in Figure S4. Films with the same space groups and orientations with respect to the substrate exist for carbon and metal oxides.[14] The symmetry change of cubic films with Im$\bar 3$m symmetry in [011] orientation along the film normal to orthorhombic Fmmm in [010] orientation is discussed in detail by Falcaro et al.[13a]

Bottom Line: A highly-ordered 3D covalent fullerene framework is presented with a structure based on octahedrally functionalized fullerene building blocks in which every fullerene is separated from the next by six functional groups and whose mesoporosity is controlled by cooperative self-assembly with a liquid-crystalline block copolymer.The new fullerene-framework material was obtained in the form of supported films by spin coating the synthesis solution directly on glass or silicon substrates, followed by a heat treatment.We also note that the 3D covalent fullerene framework exhibits a dielectric constant significantly lower than that of the nonporous precursor material.

View Article: PubMed Central - PubMed

Affiliation: Department of Chemistry and Center for NanoScience (CeNS), University of Munich (LMU), Butenandtstrasse 5-13, 81377 Munich (Germany).

No MeSH data available.


Related in: MedlinePlus