Identification of Active Gold Nanoclusters on Iron Oxide Supports for CO Oxidation

  title={Identification of Active Gold Nanoclusters on Iron Oxide Supports for CO Oxidation},
  author={Andrew A. Herzing and Christopher J. Kiely and Albert Frederick Carley and Philip Landon and Graham John Hutchings},
  pages={1331 - 1335}
Gold nanocrystals absorbed on metal oxides have exceptional properties in oxidation catalysis, including the oxidation of carbon monoxide at ambient temperatures, but the identification of the active catalytic gold species among the many present on real catalysts is challenging. We have used aberration-corrected scanning transmission electron microscopy to analyze several iron oxide–supported catalyst samples, ranging from those with little or no activity to others with high activities. High… 
Contributions of distinct gold species to catalytic reactivity for carbon monoxide oxidation
It is found that the metallic gold component in clusters or particles plays a much more critical role as the active site than the cationic single-atom gold species for the room-temperature carbon monoxide oxidation reaction.
Influence of Support Hydroxides on the Catalytic Activity of Oxidized Gold Clusters
Gold oxide nanoparticles were prepared on the native surface and a hydroxylated surface of a nonporous TiO2 support (Degussa P25). Scanning transmission electron microscopy shows the formation of
Carbon Monoxide Adsorption and Carbon Monoxide Oxidation Studies on Thiolate Supported Gold Nanoclusters Dispensed on Metallic Oxides
Thiolate-protected gold nanoclusters represent atomically well-defined active centers for catalysis with resolved crystal structures, enabling the creation of a homogeneous and defined surface. The
Application of Gold Nanoparticles in Catalysis
Abstract Following the discovery in the 1980s that clusters of gold on a nanoscale can be extremely active as catalysts, there has been an explosion in the number of reactions for which Au has shown
Small gold particles supported on MgFe2O4 nanocrystals as novel catalyst for CO oxidation
Abstract We present the study on the catalytic performance of gold particles supported on spinel type MgFe 2 O 4 nanocrystals (Au/MgFe 2 O 4 ) which exhibit high activity for low temperature CO
Active states of gold in small and big metal particles in CO and methanol selective oxidation
Role of small and big gold particles in CO oxidation and methanol selective oxidation to formaldehyde has been studied by the methods of diffuse reflectance electron spectroscopy, XRD, XPS, HRTEM and
Exceptional oxidation activity with size-controlled supported gold clusters of low atomicity.
An easy method is reported to prepare isolated gold atoms supported on functionalized carbon nanotubes and their performance in the oxidation of thiophenol with O2, showing that single gold atoms are not active, but they aggregate under reaction conditions into gold clusters of low atomicity that exhibit a catalytic activity comparable to that of sulfhydryl oxidase enzymes.
Mesoporous Metal Oxide Encapsulated Gold Nanocatalysts: Enhanced Activity for Catalyst Application to Solvent-Free Aerobic Oxidation of Hydrocarbons.
A series of experimental studies to encapsulate ultrasmall gold nanoparticles into mesoporous metal oxide via an in situ self-assembly method found that such catalysts possessed high thermal and chemical stability and could be reused more than 10 times without a remarkable loss of catalytic activity.
Morphological Effects of Gold Clusters on the Reactivity of Ceria Surface Oxygen
Well-defined {100}-faceted ceria nanocube-supported gold nanoclusters with various morphologies, including individual atom, monolayer, multilayer and nanoparticle, have been synthesized and
Imaging isolated gold atom catalytic sites in zeolite NaY.
Frequent discoveries of new gold-catalyzed reactions are leading the science; understanding has been slow to emerge; major challenges are to identify the catalytically active species and to characterize gold–support interactions.


The Structure of Catalytically Active Gold on Titania
Kinetic measurements for the catalytic oxidation of carbon monoxide show that the gold bilayer structure is significantly more active than the monolayer, thus eliminating particle shape and direct support effects.
Role of gold cations in the oxidation of carbon monoxide catalyzed by iron oxide-supported gold
Recent intense interest in catalysis by supported gold has focused mainly on the oxidation of CO at low temperatures, which offers the potential for many important applications, including the
Onset of catalytic activity of gold clusters on titania with the appearance of nonmetallic properties
Results suggest that supported clusters, in general, may have unusual catalytic properties as one dimension of the cluster becomes smaller than three atomic spacings.
Catalysis of Gold Nanoparticles Deposited on Metal Oxides
Gold in bulk is chemically inert and has often been regarded to be poorly active as a catalyst. However, when gold is small enough—with particle diameters below 10 nm—it turns out to be surprisingly
Trends in the catalytic CO oxidation activity of nanoparticles.
Based on a set of density functional theory calculations, the catalytic activity for the CO oxidation reaction over extended surfaces and small nano-particles of a number of metals is compared.
Water-enhanced catalysis of CO oxidation on free and supported gold nanoclusters.
The enhancement by water molecules of the catalytic activity of gas-phase and supported gold nanoclusters towardCO oxidation is investigated with first-principles calculations and a complete catalytic cycle of the water-enhanced CO oxidation is discussed.
Catalysis by supported gold: correlation between catalytic activity for CO oxidation and oxidation states of gold.
X-ray absorption near-edge spectra and temperature-programmed oxidation and reduction data demonstrate that Au(I) and Au(0) are both present in working MgO-supported gold catalysts for CO oxidation, demonstrating that the catalytic sites incorporate Au( I).
Enhanced Bonding of Gold Nanoparticles on Oxidized TiO2(110)
The adhesion of gold clusters is strongest on the oxidized support, and the implications of this finding for catalytic applications are discussed.
Insights into the reactivity of supported Au nanoparticles: combining theory and experiments
The origin of the extraordinary catalytic activity of gold nanoparticles is discussed on the basis of density-functional calculations, adsorption studies on single crystal surfaces, and activity
Using Three Dimensions in Catalytic Mesoporous Nanoarchitectures
Gold-titania (Au-TiO2) composite aerogels were synthesized, characterized, and tested as ambient-temperature oxidation catalysts for carbon monoxide. Adding alkanethiolate-monolayer-protected gold