Materials science research catalyst developments

Since its discovery more than 50 years ago, olefin metathesis has evolved from its origins in binary and ternary mixtures of the Ziegler-Natta type into a research area dominated by well-defined molecular catalysts. Surveys of developments up to 1993 were presented in COMC (1982) and COMC (1995). Major advances in ROMP over the last 10 years include the development of modular, stereoselective group 6 initiators, and easily handled, functional-group tolerant ruthenium initiators. The capacity to tailor polymer functionality, chain length, and microstructure has expanded applications in materials science, to the point where ROMP now constitutes one of the most powerful methods available for the molecular-level design of macromolecular materials. In addition to an excellent and comprehensive text on olefin metathesis, a three-volume handbook s has recently appeared, of which the third volume focuses specifically on applications of metathesis in polymer synthesis. 

Very recently, ultrafme metal oxides have attracted much research interests in terms of materials science and heterogeneous catalysis[10-12]. These new catalytic materials are expected to have unique catalytic properties because of their nano-scale particle sizes. In this work, a novel catalyst for selective oxidation of toluene to benzaldehyde, i.e. ultrafme complex molybdenum based oxide particles, has been developed. It has been found that the reactivity of lattice oxygen ions can be improved by decreasing the oxide particle size to nano-scale and that the ultrafme oxide particles exhibit unique catalytic properties for selective oxidation. Our results have revealed that the ultrafme complex oxide particles are potentially new catalytic materials for selective oxidation reactions. 

Research initiated at the CSIRO Division of Materials Science, Melbourne and now being continued at the University of Tasmania, has led to the development of a group of highly active and extremely versatile catalyst systems (refs. 6-8). The systems comprise nickel dithio-e-diketonate phosphine complexes (I) and (II) activated by a suitable cocatalyst such as an alkyl aluminium halide complex. 

To meet future energy demands, research on technologies that will help meet future demands on energy and transportation must be pursued today. Many of these technological developments will depend on advances made in the chemical sciences, from the development of more efficient catalysts, to improvements in separation technologies, to the development of new materials for photovoltaic cells. 

Recent research activity in carborane chemistry has been directed toward expanding the use of carborane clusters in materials science including, among others, molecular recognition systems, display devices, modular construction systems, NLO materials and special polymers. Nonetheless, their use in developing functional materials such as olefin polymerization catalysts and luminescent materials is still limited. 

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