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.