Nanostructure Processing of Advanced Catalysts and Biomaterials

Jackie. Y. Ying
Institute of Bioengineering and Nanotechnology31 Biopolis Way, The Nanos, Singapore 138669

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     Last modified: April 13, 2006

Abstract
Nanostructured materials are of interest for a variety of applications. This talk describes the synthesis and properties of two classes of nanostructured materials: nanoparticulate materials and nanoporous materials for catalytic and biomaterials applications. Nanoparticulate materials are made up of crystallites or particles of ~10 nm. They may be generated by various physical and chemical approaches with ultrahigh surface areas. Through controlled synthesis in reverse microemulsions, my laboratory has achieved complex oxide nanoparticles with ultrahigh thermal stability for the effective catalytic combustion of methane. This approach has also enabled us to derive polymeric nanoparticles for the glucose-sensitive delivery of insulin. Through chemical precipitation and additive dispersion, we have also attained nanocomposite systems as highly selective and sensitive semiconductor sensors, bioactive ceramic orthopedic implants, and efficient gene delivery vectors.

My laboratory is involved in the synthesis of novel nanoporous materials with tailored oxidation states, coordination chemistry and electronic structure. We have found that sol-gel processing can be combined with supramolecular templating agents in deriving well-defined mesoporous and microporous transition metal oxides (termed TMS). The compositional flexibility and pore size tailoring of the TMS molecular sieves open new possibilities for catalytic applications beyond the silicate-based zeolitic materials or mesoporous MCM-41. We have also attained mesocellular foams by using triblock copolymers and swelling agents in templating silicate precursors. These ultralarge-pore materials have been used to fixate organometallic ligands for the effective epoxidation, hydroxylation, Heck catalysis and asymmetric hydrogenation. The resulting heterogenized catalysts provide for excellent activity, enantioselectivity and reusability.