title: Porous capsules with a large number of active sites: nucleation/growth under confined conditions.
abstract: This work deals with the generation of large numbers of active sites and with ensuing nucleation/ growth processes on the inside wall of the cavity of porous nanocapsules of the type (pentagon)12(linker)30≡{(Mo(VI))Mo(VI)5}12{Mo(V)2(ligand)}30. A first example refers to sulfur dioxide capture through displacement of acetate ligands, while the grafted sulfite ligands are able to trap {MoO3H}(+) units thereby forming unusual {(O2SO)3MoO3H}(5-) assemblies. A second example relates to the generation of open coordination sites through release of carbon dioxide upon mild acidification of a carbonate-type capsule. When the reaction is performed in the presence of heptamolybdate ions, MoO4(2-) ions enter the cavity where they bind to the inside wall while forming new types of polyoxomolybdate architectures, thereby extending the molybdenum oxide skeleton of the capsule. Parallels can be drawn with Mo-storage proteins and supported MoO3 catalysts, making the results relevant to molybdenum biochemistry and to catalysis.
authors: Fakultät für Chemie, Universität Bielefeld, Postfach 100131, 33501 Bielefeld (Germany), Fax: (+49) 521-106-6003.
authors: Somenath
authors: S
authors: Garai
authors: Mirta
authors: M
authors: Rubčić
authors: Hartmut
authors: H
authors: Bögge
authors: Pierre
authors: P
authors: Gouzerh
authors: Achim
authors: A
authors: Müller
keywords: confinement; internal tapestry; molybdenum; nanostructures; polyoxometalates; sulfite