Molecular structure and sour gas surface chemistry of supported K2O/WO3/Al2O3 catalysts

Surface Chemistry of Silica-Titania-supported Chromium Oxide Catalysts

The interaction of chromium oxide with different titania-silica supports has been examined. The oxide supports investigated consisted of SiO,, TiO, , physical mixtures of TiO, and SiO,, a surface titania overlayer on SiO, (10% of theoretical monolayer) and a surface silica overlayer on TiO, (80% of theoretical monolayer). The supported chromium oxide catalysts were structurally characterized wi...

Molecular/electronic structure–surface acidity relationships of model-supported tungsten oxide catalysts

A series of model-supported WO3 catalysts were synthesized on preformed Al2O3, Nb2O5, TiO2, and ZrO2 supports by impregnation of aqueous ammonium metatungstate, (NH4)10W12O41·5H2O. The molecular and electronic structures of the supported tungsten oxide phases were determined with in situ Raman and UV–vis spectroscopy, respectively. The supported tungsten oxide structures are the same on all oxi...

Molecular metal catalysts on supports: organometallic chemistry meets surface science.

Recent advances in the synthesis and characterization of small, essentially molecular metal complexes and metal clusters on support surfaces have brought new insights to catalysis and point the way to systematic catalyst design. We summarize recent work unraveling effects of key design variables of site-isolated catalysts: the metal, metal nuclearity, support, and other ligands on the metals, a...

Nanoparticle-Supported Molecular Polymerization Catalysts

Homogeneous molecular catalysts are immobilzed in a well-defined fashion on individual silica nanoparticles with a narrow particle size distribution by covalent attachment. This synthetic methodology is demonstrated with modified salicylaldiminato-substituted titanium(IV) complexes incorporating a trimethoxysilaneterminated linker: dichloro-bis[κ2-N,O-6-(3-(trimethoxysilyl)propoxyphenylimino)-2...

Surface chemistry and reactivity of well-defined multilayered supported M1Ox/M2Ox/SiO2 catalysts