Catalytic CO Oxidation over Au Nanoparticles Supported on CeO2 Nanocrystals: Effect of the Au–CeO2 Interface

Gold nanoparticles (NPs) have attracted attention due to their superior catalytic performance in CO oxidation at low temperatures. Along with the size and shape of Au NPs, the catalytic function of Au-catalyzed CO oxidation can be further optimized by controlling the physicochemical properties of oxide-supporting materials. We applied a combinatorial approach of experimental analyses and theoretical interpretations to study the effect of a surface structure of supporting oxides and the corresponding CO oxidation activity of supported Au NPs. We synthesized Au NPs (average d ≈ 3 nm) supported on shape-controlled CeO2 nanocrystals, Au/CeO2 cubes, and Au/CeO2 octahedra for experimental analyses. The catalysts were modeled as Au/CeO2(100) and Au/CeO2(111) via density functional theory (DFT) calculations. The DFT calculations showed that the O–C–O type reaction intermediate could be spontaneously formed at the Au–CeO2(100) interface upon sequential multi-CO adsorption, accelerating CO oxidation via the Mars-va...