Photochemical transformation of C60 and C70 films

Fullerenes possess high chemical stability, large specific surface area, good electrical conductivity and unique three-dimensional structure. In this paper, we provide a general overview of the latest research results of fullerene-based photocatalysts. Firstly, the current status of semiconductor materials and fullerenes in photocatalytic applications are briefly introduced. Secondly, introduced action mechanisms of photocatalysts modified by fullerene C60 and its derivatives, including basic structure, exclusive properties and its effect in photocatalysis and material preparation process. Thirdly, factors affecting material effectiveness and the synthesis strategy of composite photocatalyst modified by fullerene are introduced. Meanwhile, the application advances of the photocatalysts are introduced, including in the degradation of pollutants, organic synthesis, hydrogen production, antibacterial and disinfection in water. Finally, the development trends of fullerenes and their derivatives in photocatalysis are also summarized, including theoretical calculations, the morphological structure control, stable derivatives and increase the selectivity, and new other types of fullerene materials.

Advances in photocatalysis based on fullerene C60 and its derivatives: Properties, mechanism, synthesis, and applications

Single crystal of pure C70 are grown from the vapour phase and the structure and morphology of these crystals is studied. By means of X-ray diffraction and TEM measurements five different phases are observed. The observed phases are (from high to low temperatures) fcc, rhombohedral, ideal hcp (c/a=1.63), deformed hcp (c/a=1.82) and a monoclinic phase. The occurrence of these different phases and the phase transitions is accounted for in a simple model. For the monoclinic structure a model for the stacking of the orientationally ordered molecules in the lattice is proposed. For both the hcp and fcc phases a Lennard-Jones type interaction potential is used to calculate bond strengths, lattice energies and the theoretical morphology.

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The structure of different phases of pure c-70 crystals

Electronic properties of carbon nanostructures

Fullerenes, containing five- and six-membered carbon rings, of which C 60 and C 70 are the prominent members, exhibit phase transitions associated with orientational ordering. When C 60 is suitably doped with electrons, it shows novel superconducting and magnetic properties. We review these and other properties of fullerenes in bulk or in film form along with the preparative and structural aspects. Carbon nanotubes and onions (hyperfullerenes) are the other forms of carbon whose material properties have aroused considerable interest. Besides discussing these new forms of carbon, we briefly introduce other possible forms, such as those involving five-, six- and seven-membered rings and hybrids between diamond and graphite.

Fullerenes, nanotubes, onions and related carbon structures

https://repository.ubn.ru.nl/bitstream/handle/2066/99036/99036.pdf

Growth and morphology of C60 crystals

Cubic as well as hexagonal single crystals of C70 have been grown and investigated by electron diffraction, electron microscopy and x-ray diffraction Several phase transitions have been detected and crystallographic models are proposed Hexagonal crystals, stable at room temperature with c/a = 163 will undergo two transitions, upon cooling First the c/a ratio will increase to 182 owing to c-axis alignment of the molecules; at a lower temperature the molecules will orientationally order, resulting in a monoclinic structure

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Structural phase-transitions in c-70

Quasicrystals and related phases were grown to study their morphology and to try to gain sonie insight into their growth mechanism. Using different characteriz-ation techniques a relationship between morphology, composition and structure of the quasicrystals and related phases is established. This relationship is qualitatively explained by an epitaxial growth mechanism.

H. Meekes

Papers

The structure of different phases of pure c-70 crystals

Growth and morphology of C60 crystals

Structural phase-transitions in c-70

On the relationship between morphology, composition and structure of Al-Cu-Fe crystals and quasicrystals

A study on the morphology and stability of incommensurately modulated structures; a case study of ((CH3)4N)2ZnCl4−xBrx and AuTe2