Chapter 3 Probing the unique size-dependent properties of small Au clusters, Au alloy clusters, and CO-chemisorbed Au clusters in the gas phase

Abstract

Publisher Summary This chapter reviews recent studies in the laboratory on the structural and electronic properties, and chemical bonding in elemental gold clusters, gold alloy clusters, and CO-chemisorbed gold clusters in the gas phase, which represent further examples to demonstrate the diverse and expanding chemistry of gold. The chapter also studies the planarity in small elemental Au cluster anions; the tetrahedral Au20 cluster; icosahedral gold cage clusters. The findings are not only fundamental in cluster science and physical chemistry, but may also have important potential applications. This series of stable cage clusters demonstrated the potential of fine-tuning electronic properties of gold with the central heteroatom. The chapter illustrates that this new concept may not only extend the understanding of Au chemistry but may also be highly valuable in predicting the structures and chemical bonding in many Au alloy clusters. The PES data also revealed important activation mechanisms of Au clusters by CO chemisorption and provided a natural interpretation for cooperative coadsorption of CO and O2 on Au clusters, which may hold the key for understanding nanogold catalytic CO oxidation at low temperatures. Gold, the noblest metal in the periodic table, seems to hold many surprises in the nano regime. It is anticipated that many more secrets of nanogold are still waiting to be discovered.