Atomically Monodisperse Gold Nanoclusters Catalysts with Precise Core-Shell Structure

Abstract

Abstract:The emphasis of this review is atomically monodisperse Au n nanoclusters catalysts (n = number of metal atom in cluster) that are ideally composed of an exact number of metal atoms. Au n which range in size from a dozen to a few hundred atoms are particularly promising for nanocatalysis due to their unique core-shell structure and non-metallic electronic properties. Au n nanoclusters catalysts have been demonstrated to exhibit excellent catalytic activity in hydrogenation and oxidation processes. Such unique properties of Au n significantly promote molecule activation by enhancing adsorption energy of reactant molecules on catalyst surface. The structural determination of Au n nanoclusters allows for a precise correlation of particle structure with catalytic properties and also permits the identification of catalytically active sites on the gold particle at an atomic level. By learning these fundamental principles, one would ultimately be able to design new types of highly active and highly selective gold nanocluster catalysts for a variety of catalytic processes.

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

“…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). The parent ion at m/z 2839 was selected that contains an envelope of 31 detectable peaks with unit mass difference, ranging from m/z 2823 to 2853.…”

“…Even when the cluster is stable, fragmentation is common under ESI conditions. For example, the stable Au 25 (SR) 18 cluster shows a fragment in the mass spectrum due to the Au 4 (SR) 4 loss. 52 Even the stable Ag 44 (SR) 30 cluster, for which the crystal structure was determined recently, 35,36 shows several fragments due to Ag m (SR) n losses.…”

In Situ Synthesis of Bimetallic Hybrid Nanocatalysts on a Paper-Structured Matrix for Catalytic Applications

“…In particular, nano-sized metal particles attract increasing attention as highly active heterogeneous catalysts, due to their unique electronic properties and extremely large specific surface areas [4,5]. For example, gold nanoparticles (AuNPs) exhibit good catalytic activities in various chemical reactions [6][7][8][9][10][11][12], such as the reduction of 4-nitrophenol (4-NP) to 4-aminophenol (4-AP), which is a useful intermediate for the production of analgesic and antipyretic drugs, in the liquid phase [10], and the low-temperature oxidation of carbon monoxide (CO) in the gas phase [11], even though ordinary bulk Au is known to be an inefficient catalyst [13,14].…”

New Frontiers in Gold Catalyzed Reactions

“…It comprises 5 reviews and 9 research articles. The first review article by Sun et al [1] covers aspects of atomically monodisperse gold nanoclusters, with precise core-shell structure, which are fundamental to design new types of highly active and selective gold catalysts for a variety of catalytic processes. The role of surface steps and surface doping in the catalytic reactions on model gold surface was addressed through Density Functional Theory (DFT) based calculations by Gomes and coworkers [2] in a second review.…”