Thiolate‐Protected Au_n Nanoclusters as Catalysts for Selective Oxidation and Hydrogenation Processes

Abstract

Thiolate‐protected Aun clusters are exploited as homogeneous and supported catalysts for two chemical processes: i) the selective oxidation of styrene by O2 to benzaldehyde and ii) the chemoselective hydrogenation of α,β‐unsaturated ketone to α,β‐unsaturated alcohol. The results demonstrate that a quantum‐size effect in Aun clusters plays a critical role in their catalysis. This work highlights the importance of pursuing quantum‐sized gold clusters for catalysis.

Investigating the structural evolution of thiolate protected gold clusters from first-principles

“…Aikens and co-workers have theoretically studied this process by examining the electron and hydride addition to gold(I)-thiolate oligomers (Au N (SR) N , N ¼ 3-7). 153 The addition of a hydride ion to gold(I)-thiolate oligomers led to the production of free thiols and Au(0)-containing chain-like oligomers, which is considered as a possible intermediate for the [149][150][151] Few theoretical studies have been reported on the origin of catalytic activity and the structure-activity relationship of these clusters. With more atomic structures of thiolate-protected gold clusters being determined, a better understanding of the structure-activity selectivity relationship is expected in the years to come.…”

Isolation and Tandem Mass Spectrometric Identification of a Stable Monolayer Protected Silver–Palladium Alloy Cluster

“…Cluster 3 ( Figure S5D in the Supporting Information) does not show significant peaks in both negative and positive modes. For cluster 2, the spectrum shows ( Figure 2 and Figure S5C in the Supporting Information) a molecular ion peak at m/z 2839 along with some fragments at m/z 2604 and 2204, which have been assigned as [Ag 5 10 ] − , respectively. The fragments are due to (SePh+Ph) and Ag 2 Pd(SePh) 2 losses, respectively ( Figure 2).…”

“…MS/MS of the fragment at m/z 2604 was also studied ( Figure S6 in the Supporting Information), and for this case, successive ligand losses were seen and the metal core remains intact throughout. MS 2 of [Ag 5 Pd 4 (SePh) 10 Se] − produces two new peaks due to consecutive losses of two units of (SeR+R), part of the ligand. Mass difference for the fragments obtained from MS 3 of the peak at m/z 2374 corresponds to the losses of two units of selenium and one R. Similar trends have been observed for MS 4 (11.7%); abundances are given as percentages).…”

Atomically Monodisperse Gold Nanoclusters Catalysts with Precise Core-Shell Structure

“…Recently, Jin et al reported the Au n (SR) m nanocluster catalysts for selective oxidation of styrene using three robust supersmall Au n nanoclusters, including Au 25 (1.0 nm), Au 38 (1.3 nm) and Au 144 (1.6 nm) [23,26]. The catalytic activity of Au n nanocluster catalysts exhibits a strong dependence on size (n); the smaller Au n (SR) m nanoclusters give rise to a much higher catalytic activity.…”

“…Overall, the non-metallic behavior of Au n in both size regimes is particularly important for nanocatalysis. More importantly, on the basis of their atom packing structures and unique electronic properties, one could indeed study a precise correlation of structural properties with catalytic properties, identify the catalytically active sites on the gold particle and unravel the nature of gold catalysis [21][22][23][24][25][26][27]. This has long been an important task in nanocatalysis [28][29][30][31][32][33][34][35][36].…”