Size- and Structure-specificity in Catalysis by Gold Clusters

Abstract

Although gold in bulk is poorly active as a catalyst, it exhibits surprisingly high catalytic activity when deposited as nanoparticles (NPs) on base metal oxides. The catalytic performance of supported gold NPs can be created by choosing the kind of support materials, by controlling the size of gold, and by building up strong contact of gold with the supports. Since perimeter interfaces around gold NPs act, in principle, as the active sites for oxidation and hydrogenation, gold should be smaller than 10 nm in diameter. A new area of research is clusters, which are smaller than 2 nm in diameter and less than 200 atoms. Gold clusters possess electronic structures different from those of bulk gold and at the same time provide increased fractions of edges and corners which are highly unsaturatedly coordinated sites. Accordingly, gold clusters will be blessed by unique catalytic performance, and many examples have recently been emerging. This article summarizes such examples in terms of "size-and structure-specificity," covering gas-phase free clusters, polymer-or organic-ligand-stabilized clusters in liquid phase, and clusters supported on base metal oxides, carbon materials, and organic polymers for gas-phase and liquid-phase reactions.

Reduced sintering of mass-selected Au clusters on SiO2by alloying with Ti: an aberration-corrected STEM and computational study

“…Since then, Au has attracted growing attention as a catalyst and become the preeminent example of a size effect in heterogeneous catalysis. [9][10][11] As CO oxidation is one of the simplest reactions which Au can catalyse, and CO is frequently used as a probe molecule in surface science, CO oxidation on TiO 2 supported Au nanoparticles has become a prototypical model system in Au catalysis, [12][13][14][15] and numerous studies have been reported regarding the reaction mechanisms, [16][17][18] active sites, 11,[19][20][21] and active species. 22,23 Looking at the experimentally measured catalytic activities of Au nanoparticles on different supports in the CO oxidation reaction, two main conclusions can be drawn.…”

Ethanol and Water Adsorption on Transition-Metal 13-Atom Clusters: A Density Functional Theory Investigation within van der Waals Corrections

“…[17][18][19][20] It has been reported that Au NPs with diameter from 1.0 nm to 5.0 nm exhibits surprisingly high activity and selectivity for several reactions. 16,19,21,22 Thus, there are large expectations that TM NPs supported on oxides can improve the breaking of the strong C−C σ bond and to reduce the number of undesirable intermediate compounds, [1][2][3]14 which present a great challenge for ethanol SRR catalysts. Platinum (Pt) NPs of about 3 nm supported on carbon black have been studied, 9,10,23 as well as combined with SnO 2 , 10 however, acid acetic is one of the predominant undesirable products.…”

Sonogashira cross-coupling on the Au(1 1 1) and Au(1 0 0) facets of gold nanorod catalysts: Experimental and computational investigation

“…Over the past few decades, colloidal gold nanoparticles (NPs) have gained tremendous attention as catalysts for organic reactions such as selective oxidation, hydrogenation, and carbonAcarbon coupling reactions due to the robust and green nature of gold catalysts [10][11][12][13][14][15][16]. According to a previous work by Lambert et al, oxide-supported gold nanoparticles are active catalysts for Sonogashira cross-coupling reactions between iodobenzene (IB) and phenylacetylene (PA) [17].…”