PREPARATION AND CATALYTIC ACTIVITY OF NANO-SCALE AU ISLANDS SUPPORTEDON TIO2

Titania-supported gold catalysts (Au/TiO2) prepared by the ionized clu ster beam (ICE) method have been studied by STM, TEM, X-ray diffractio n and assessed for their catalytic activity with the oxidation of CO. The temperature dependence of the CO oxidation for Au/TiO2 catalysts i ndicated that the catalytic activity was enhanced both by using anatas e type of TiO2 supports and by depositing Au at an accelerating potent ial of 3 kV. For CO oxidation, O-2 molecules, absorbed on the TiO2 sup ports, migrate and react with CO molecules at the edge of the nano-sca le Au islands. The enhancement of CO oxidation is due to the increase of absorption and migration for these O-2 and CO molecules. Thus, high activity of Au/TiO2 catalysts with good thermal stability can be obta ined.