INOR 5 |
| Transition metal polyoxometalates (POMs) represent a well-defined class of inorganic supramolecular structures with diverse properties and potential applications in fundamental and applied science. To implement POMs in functional materials and nanotechnological devices it will be of paramount importance to combine and position POM-clusters in well-defined device architectures. Several methods are available to implement POMs in materials science. One method rests on ion-exchange of the POM counter ions with surfactants that permits to tailor the surface chemical properties of POMs. These materials combine the physicochemical properties of the inorganic POM core with the diverse assets of organic compounds including wetting, adhesion, solubility as well as bio-compatibility. The hydrophobic nature of surfactant-encapsulated clusters (SECs) permits construction of highly-ordered arrays through the Langmuir-Blodgett technique. Also, SECs form organized assemblies on the basal plane of graphite, which permits to study individual or assemblies of SECs. Beyond modifying individual clusters lies the challenge of fabricating highly-ordered ensembles that approach macroscopic length scales to fully exploit the properties of these functional units. Here, it will be necessary to improve existing methods and to develop new methodologies to engineer hierarchical architectures. Thin films with nanometer thickness control are readily assembled by utilizing primarily electrostatic interactions of oppositely charged POMs and polyelectrolytes. The permeability of such layers is attractive for heterogeneous catalysis, electrochemical and molecular recognition devices, such as sensors. |
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Polyoxometalates and Related Clusters in Chemistry and Nanoscience
9:00 AM-12:30 PM, Sunday, August 19, 2007 BCEC -- 204 A/B, Oral
Division of Inorganic Chemistry |