摘要
Ultrasmall Au-10 clusters have a unique electronic structure and can act as a charge reservoir to donate electrons or accept charges. This is particularly important for catalysis, since it leads to facile charge transfer across the interface between the gold species and the oxide substrate. To determine the electronic and structural effects of Au-10 on the catalytic oxidation, a TiO2 charge carrier was chosen as the substrate to anchor Au-10 for olefin oxidation. Au-10 supported on TiO2-RP (RP = pyramid-capped columnar structure) exhibited superior catalytic activity to Au-10/TiO2 nanotubes and Au-10/P25. In addition, the supported Au-10 clusters gave rise to higher activity than supported Au-20, Au-144 clusters, and 5 nm Au nanocrystals. The superior catalytic ability of Au-10/TiO2-RP arises from the charge/discharge effect of the Au-10/TiO2-RP interface, which effectively improves the formation of active oxygen species on electron-rich gold atoms at the terminal position of Au-10, and promotes the activation of olefin C=C bonds on the electron-deficient gold atoms of Au-10.
