Mechanism and Active Sites of the Oxidation of CO over Au/TiO2

摘要

Gold nanoparticles supported on titanium oxides are highly active catalysts for the oxidation of CO even at low temperature.'1 Despite extensive research to determine the reaction mechanism and the active sites on a molecular scale, there is still no consensus about 1) the the active sites and the mechanism of activation of O2 molecules and 2) the role of moisture and its influence on the activity of the catalysts.For instance, although most research groups agree that small Au° nanoparticles are the predominant catalytic species, other groups have proposed that cationic gold species, undercoordinated sites on the gold nanoparticles, or electron-rich gold nanoparticles play an essential role in the reaction.