Gold Nanoclusters as Electrocatalysts for Energy Conversion

Gold nanoclusters (Au-n NCs) exhibit a size-specific electronic structure unlike bulk gold and can therefore be used as catalysts in various reactions. Ligand-protected Au-n NCs can be synthesized with atomic precision, and the geometric structures of many Au-n NCs have been determined by single-crystal X-ray diffraction analysis. In addition, Au-n NCs can be doped with various types of elements. Clarification of the effects of changes to the chemical composition, geometric structure, and associated electronic state on catalytic activity would enable a deep understanding of the active sites and mechanisms in catalytic reactions as well as key factors for high activation. Furthermore, it may be possible to synthesize Au-n NCs with properties that surpass those of conventional catalysts using the obtained design guidelines. With these expectations, catalyst research using Au-n NCs as a model catalyst has been actively conducted in recent years. This review focuses on the application of Au-n NCs as an electrocatalyst and outlines recent research progress.