Spiers Memorial Lecture. Role of perimeter interfaces in catalysis by gold nanoparticles.

Gold can be deposited as nanoparticles (NPs) of 2 to 5 nm in diameter on a variety of materials such as metal oxides and carbides, carbons, organic polymers and exhibits surprisingly high catalytic activities for many reactions in both gas and liquid phases. The mechanisms for the genesis of catalysis by gold NPs is discussed based on real powder catalysts and model single crystal catalysts for two simple reactions, low-temperature oxidation of CO in which gold NPs catalysts are exceptionally active and for dihydrogen dissociation in which gold NPs catalysts are still poorly active. For both the two reactions, it has been revealed that reactions take place at perimeter interfaces around gold NPs.