Role of nanostructured dual-oxide supports in enhanced catalytic activity: theory of CO oxidation over Au/IrO2/TiO2

The synergetic effect in multicomponent catalysts is a topic of profound industrial importance and intense academic interest. On a newly identified multicomponent catalyst, Au/IrO(2)/TiO(2), first-principles density-functional theory is analyzed to clarify the outstanding catalytic activity of the system for oxidative reactions at high temperatures. By comparing CO oxidation on interfaces and single-component surfaces, it is revealed that a high dispersion of a more active oxide (IrO2), on a more inert oxide (TiO2) is the key. It preserves the sintering resistance of Au supported on less active oxides, while at the same time promoting oxidative reactions that occur at the Au/active-oxide interface.