Advanced Materials

Does Microgravity Influence Self-Assembly??

Authors

  • Dr. Ömer Dag,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Homayoun Ahari,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Neil Coombs,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Tong Jiang,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Patricia P. Aroca-Ouellette,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Srebri Petrov,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Igor Sokolov,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. Atul Verma,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Gregory Vovk,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Dr. David Young,

    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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  • Prof. Geoffrey A. Ozin,

    Corresponding author
    1. Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
    • Materials Chemistry Research Group Lash Miller Chemistry Department University of Toronto 80 St. George Street Toronto, Ontario, M5S 3H6 (Canada)
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    • Geoffrey A. Ozin received his B.Sc. degree in chemistry from King's College, University of London, in 1965, and his D.Phil. in inorganic chemistry from Oriel College, University of Oxford, in 1967. From 1967 to 1969 he was an ICI Post Doctoral Fellow at Southampton University before joining the chemistry faculty at the University of Toronto in 1969, where he is a Full Professor. His field of specialization is interdisciplinary materials chemistry with a focus on nano-chemistry and his current research interests include solidstate, supramolecular, host–guest inclusion, biomimetic, and microgravity chemistry.

  • Prof. Christian Reber,

    1. Chemistry Department University of Montreal Montreal, Quebec, H3C 3J7 (Canada)
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  • Yanick Pelletier,

    1. Chemistry Department University of Montreal Montreal, Quebec, H3C 3J7 (Canada)
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  • Dr. Robert L. Bedard

    1. Universal Oil Products (UOP) 25 East Algonquin Des Plaines, IL 60017-5017 (USA)
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  • We dedicate this paper to Dr. Edith Flanigen on the occasion of her recent retirement from research at UOP Edith had the amazing foresight to realize that crystalline porous materials should not just be viewed in terms of traditional zeolites and the linking together of tetrahedral silicate and aluminate building blocks but, rather more holistically, in the context of the entire periodic table. Now many of the elements of the periodic table are being linked together into a myriad of architecturally exquisite open frameworks. There is now as much research with open network materials as there is with dense-packed solids. The creative and lateral thinking of Dr. Robert Bedard around 1985 at Union Carbide led him, together with Dr. Edith Flanigen and two other coworkers, to invent the microporous metal sulfide class of materials in 1989 [1]. This is now an emerging and exciting subfield of materials chemistry [2]

Abstract

The templated syntheses of TMA2Sn3S7 and TBA2Sn4S9 (where TMA is tetramethylammonium and TBA is n-tetrabutylammonium) microporous layered tin(iv) sulfides have been carried out under both microgravity (μG) and earth (1G) conditions in order to elucidate the influence of gravity on the self-assembly and crystal-growth processes of this class of materials. The μG experiments were conducted on board the May 1996 Endeavour STS-77 NASA space-shuttle flight. It was determined that the long-range ordering of the porous layers and the population of defects but not the short-range ordering within the layers is influenced by gravity. Bulk and surface crystallinity, smoothness of crystal faces, optical quality, crystal habits, registry of the porous layers, and accessible void volume to adsorbates were found to be improved in the space-grown crystals. This is probably because the forces associated with the organization of the porous layers are expected to be weak and sensitive to the elimination of buoyancy-driven convective flows and Stokes sedimentation effects in a microgravity environment. One can draw an analogy to the weak forces between protein macromolecules and the established effect of microgravity on improving the diffraction quality of crystals harvested in space.

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