Molecular precursors for tailored metal

K-edge spectram, for ruthenium, 35 32, 77 molecular precursors for tailored metal catalysts, 38 298... 

Molecular precursors for tailored metal catalysts, 38 283-392 see also Bimetallic catalysts, cluster-derived Zeolites carbon-supported, 38 389-390 chemical interaction between clusters and supports, 38 295-296... 

Ichikawa, M., Metal cluster compounds as molecular precursors for tailored metal catalysts. Adv. Catal. 38,283 (1992). 

Metal Cluster Compounds as Molecular Precursors for Tailored Metal Catalysts... 

The continued development of new single-source molecular precursors should lead to increasingly complex mixed-element oxides with novel properties. Continued work with grafting methods will provide access to novel surface structures that may prove useful for catalytic apphcations. Use of molecular precursors for the generation of metal nanoparticles supported on various oxide supports is another area that shows promise. We expect that the thermolytic molecular precursor methods outlined here will contribute significantly to the development of new generations of advanced materials with tailored properties, and that it will continue to provide access to catalytic materials with improved performance. 

A variety of metal cluster compounds have been chemically bound on amorphous metal oxides and entrapped inside zeolite cages by new preparative tools such as surface organometallic chemistry and the so-called ship-in-bottle technique. They oflier much promise as molecular precursors for rational preparation of tailored metal catalysts having a uniform distribution of discrete metal-bimetallic ensembles, namely, organometallics which are active for catalytic reactions. They also provide advantages as metal precursors to achieve higher metal dispersions and well-managed metal... 

The key effect of oxide supports on the catalytic activities of metal particles is exerted through the interface between oxides and metal particles. The key objective of this study is to develop synthesis methodologies for tailoring this interface. Here, an SSG approach was introduced to modify the surface of mesoporous silica materials with ultrathin films of titanium oxide so that the uniform deposition of gold precursors on ordered mesoporous silica materials by DP could be achieved without the constraint of the low lEP of silica. The surface sol-gel process was originally developed by Kunitake and coworkers.This novel technology enables molecular-scale control of film thickness over a large 2-D substrate area and can be viewed as a solution-based... 

In addition to practical applications, metal cluster-derived catalysts, particularly intrazeolite metal cluster compounds, may aid in the identification of catalytically important bonding and structural patterns and thereby further our molecular understanding of surface science and heterogeneous catalysis. The ship-in-bottle technique for the synthesis of bulky metal-mixed metal cluster compounds inside zeolites and/or interlayered minerals has gained growing attention for the purpose of obtaining catalytic precursors surrounded by the interior constraint, imposing molecular shape selectivity. Such approaches may pave the way to offer the molecular architecture of hybrid (multifunctional) tailored catalysts to achieve the desired selectivity and stability for industrial processes. 

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