We present a successive microfluidic approach to create and characterize hierarchical catalyst structures consisting of metal-decorated nanoparticles that are assembled into porous microparticles ("supraball" catalysts). First, using a silicon microreactor, platinum nanoparticles with a very narrow size distribution are grown and immobilized uniformly onto iron oxide/silica core-shell nanospher...

Anionic platinum carbonyl cluster has been ion paired with cinchonidium groups that are chemically bound to the surface of MCM-41 and fumed silica. In the hydrogenation of methyl pyruvate or acetophenone the fumed silica-based catalyst gives zero enantioselectivity, but under optimum conditions enantiomeric excesses of > 90 and ∼ 40%, respectively, are obtained with the MCM-41-based catalyst.

Our first-principles density functional theoretical modeling suggests that NO oxidation is feasible on fully oxidized single θ-Al2O3 supported platinum atoms via a modified Langmuir-Hinshelwood pathway. This is in contrast to the known decrease in NO oxidation activity of supported platinum with decreasing Pt particle size believed to be due to increased platinum oxidation. In order to validate...

in this research na-y was synthesized by hydrothermal method and used as support for preparation of sn/pt/na-y catalysts using two different tin precursors, bu3sn(cl) and sncl2.2h2o, by sequential impregnation, in which the pt  was deposited first and in the next step sn was deposited. the catalysts were characterized by h2 chemisorption, transmission electron microscopy (tem), scanning electro...

Introduction The preparation and characterization of nanophase materials has received considerable attention in recent years, given their potential for improved performance as catalysts, high-strength materials, and semiconductor devices. For example, a recent breakthrough by Sun et al. (1) in the synthesis of highly-dispersed, silica-supported iron-platinum (FePt) bimetallic nanoclusters of co...

Performance of low temperature fuel cells depends critically on the nanostructures of the material components in the electrodes and membranes. Some studies are reported here for 1) mixed metal nanoparticles supported on mesoporous carbon and 2) modification of nanopores of Nafion via in-situ polymerization of furfuryl alcohol. The anodic oxidation of small organic molecules such as alcohols in ...

bis(2-r-ind)zrcl2 (r: h or phenyl) was supported on different types of silica by in situ impregnation method and used for ethylene polymerization. in this method, the step of catalyst loading on support was eliminated and common alkyl aluminum (triisobutylaluminum, tiba) cocatalyst was used instead of expensive methyl aluminiumoxane (mao) cocatalyst in the polymerization. the effect of surface ...

A mesostructured cellular foam (MCF) silica was applied to support gold (Au) – platinum (Pt) alloy nanoparticles (NPs) for benzyl alcohol partial oxidation. catalytic synergy on bimetallic (Au)-platinum nanoparticle (NP) catalyst, referring that introducing Au Pt leading a higher performance has been observed. However, the essence of this synergistic effect is still under debate. In work, serie...

The hydroformylation of alkenes is a major commercial process used for the production of oxygenated organic compounds. When the hydroformylation reaction is performed using a homogeneous catalyst, an organic or aqueous solvent is employed, and a significant effort must be expended to recover the catalyst so it can be recycled. Development of a selective heterogeneous catalyst would allow simpli...