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Choudhary, Ajay; Sivadinarayana, C.; Datye, Abhaya K.; Kumar, Deepak; Goodman, D. W.

doi:10.1023/a:1022694505504

Cited by 198 publications

(116 citation statements)

References 12 publications

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“…Gold catalyzes various hydrogenation reactions such as the hydrogenation of alkenes (3)(4)(5)(6)(7)(8)(9)(10)(11)(12), alkadiens (13)(14)(15)(16)(17)(18) alkynes (13,(19)(20)(21)(22)(23)(24)(25), , -unsaturated carbonyl compounds and nitro compounds (47)(48)(49)(50)(51)(52)(53). In contrast to traditional hydrogenation catalysts such as platinum, palladium or ruthenium, which require modification, it often shows remarkable selectivities when multiple functional groups are present.…”

Section: Introductionmentioning

confidence: 99%

“…Supported gold catalysts were very selective in purifying alkene streams, to prevent poisoning of the polymerization catalysts and ensure pure products (54). On the other hand, over the industrially-used palladium catalysts, oligomers are formed, that reduce lifetime (22). Selectivities up to 90% were obtained over gold for the selective hydrogenation of , -unsaturated carbonyl compounds to the corresponding unsaturated alcohols, which are important intermediates in the production of fine chemicals and pharmaceuticals (17,41,45-46,).…”

Section: Introductionmentioning

confidence: 99%

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Hydrogenation over gold catalysts: The interaction of gold with hydrogen

Kartusch

Bokhoven

2009

Gold Bull

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Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Hydrogenation over gold catalysts: The interaction of gold with hydrogen

Kartusch

Bokhoven

2009

Gold Bull

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“…This was demonstrated for a variety of reactions. A partial list includes vinylacetate(VA)synthesis, 7 olefinsandacetylenehydrogenation, 8,9 and acetylene cyclization to benzene. [10][11][12] Since the first report on the trimerization reaction of acetylene to benzene by Tysoe et al, 10 this reaction is considered structure sensitive with the Pd(111) facet the most active.…”

Section: Introductionmentioning

confidence: 99%

“…Interestingly, similar selectivity toward ethylene production described here for the BLAG Pd-Au bimetallic clusters was reported also for similar clusters sizes of Au-Pd/TiO 2 catalysts prepared by redox wet preparation methods. 9 Suppression of the benzene formation pathway relative to ethylene formation by small, wires-like bimetallic clusters formed via the BLAG method (Figure 4) can be explained by the lack of extended (111)-like surfaces of Pd or Au-Pd, the ensemble effect. Focusing on the benzene formation, however, one clearly realizes the reactivity enhancement, presumably due to electronic effect of low temperature bimetallic alloy formation in the BLAG procedure.…”

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confidence: 99%

Chemical Reactivity of Pd−Au Bimetallic Nanoclusters Grown via Amorphous Solid Water as Buffer Layer

2009

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Bimetallic Pd-Au nanoclusters were prepared on SiO 2 /Si(100) via amorphous solid water (ASW) as buffer layer. Selective growth pathways have led to segregated palladium and gold clusters or alloy bimetallic crystallites. Morphology and chemical composition were determined by AFM, SEM, and HR-TEM coupled to EDX analysis. Correlation between clusters morphology and composition to their chemical reactivity is reported for the first time. Temperature programmed reaction studies revealed that conversion of acetylene to ethylene and trimerization to benzene are significantly enhanced over crystalline alloy Pd-Au clusters when compared to clean Pd. A remarkable selectivity toward ethylene formation over benzene is unique to the alloy bimetallic clusters grown via ASW buffer layer on silica, presumably due to suppression of the trimerization pathway. The intrinsic, modified electronic properties of the bimetallic alloy clusters are believed to drive their enhanced chemical reactivity when compared with the pure Pd clusters.

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“…A short while ago it was discovered that, unlike bulk gold, small gold clusters are chemically active and are promising catalysts for partial oxidation [1][2][3][4][5][6][7][8][9][10][11][12][13][14] and partial hydrogenation [15][16][17] reactions. We are particularly interested in Haruta's discovery 1 that Au clusters, supported on TiO 2 , epoxidize propene with very high selectivity.…”

Section: Introductionmentioning

confidence: 99%

Binding of propene on small gold clusters and on Au(111): Simple rules for binding sites and relative binding energies

Chrétien

Gordon

Metiu

2004

The Journal of Chemical Physics

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We use density functional theory(DFT) to investigate the bonding of propene to small gas-phase gold clusters and to a Au(111) surface. The desorption energy trends and the geometry of the binding sites are consistent with the following set of rules.(1) The bond of propene to gold is formed by donation of electron density from the highest occupied molecular orbital (HOMO) of propene to one of the low-lying empty orbitals [denoted by LUMO1, LUMO2, … (LUMO-lowest unoccupied molecular orbital)] of the gold cluster. (2) Propene binds to a site on the Au cluster where one of the low-lying LUMOs protrudes in the vacuum. Different isomers (same cluster, but different binding sites for propene) correspond to sites where different low-lying LUMOs protrude in space. (3) The desorption energy of the lowest energy isomer correlates with the energy of the lowest empty orbital of the cluster; the lower the energy of that LUMO, the higher the desorption energy. (4) If the lowest-lying LUMO protrudes into space at two nonequivalent sites at the edge of a cluster, propene binds more strongly to the site with the lowest coordination. These rules are consistent with the calculated bond energies and geometries for [Aun(C3H6)]q, for n=1−5 and n=8 and q=−1, 0, +1. Based on them we have made a number of predictions that have been confirmed by DFT calculations. The bond of propene to gold is strengthened as the net charge of the cluster varies from −1, to zero, to +1. Compared to a gas-phase cluster, a cluster on a support binds propene more strongly if the support takes electron density from the cluster (e.g., a Au cluster on a goldsurface) and more weakly if the support donates electron density to the cluster (e.g., a Au cluster on an oxygen vacancy on an oxide surface). KeywordsGold, Binding sites, Density functional theory, Desorption, Oxide surfaces Disciplines Chemistry CommentsThe following article appeared in Journal of Chemical Physics 121 (2004) We use density functional theory ͑DFT͒ to investigate the bonding of propene to small gas-phase gold clusters and to a Au͑111͒ surface. The desorption energy trends and the geometry of the binding sites are consistent with the following set of rules. ͑1͒ The bond of propene to gold is formed by donation of electron density from the highest occupied molecular orbital ͑HOMO͒ of propene to one of the low-lying empty orbitals ͓denoted by LUMO1, LUMO2, ... ͑LUMO-lowest unoccupied molecular orbital͔͒ of the gold cluster. ͑2͒ Propene binds to a site on the Au cluster where one of the low-lying LUMOs protrudes in the vacuum. Different isomers ͑same cluster, but different binding sites for propene͒ correspond to sites where different low-lying LUMOs protrude in space. ͑3͒ The desorption energy of the lowest energy isomer correlates with the energy of the lowest empty orbital of the cluster; the lower the energy of that LUMO, the higher the desorption energy. ͑4͒ If the lowest-lying LUMO protrudes into space at two nonequivalent sites at the edge of a cluster, propene binds more strong...

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Cited by 198 publications

References 12 publications

Hydrogenation over gold catalysts: The interaction of gold with hydrogen

Hydrogenation over gold catalysts: The interaction of gold with hydrogen

Chemical Reactivity of Pd−Au Bimetallic Nanoclusters Grown via Amorphous Solid Water as Buffer Layer

Binding of propene on small gold clusters and on Au(111): Simple rules for binding sites and relative binding energies

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