Onset of catalytic activity of gold clusters on titania with the appearance of nonmetallic properties

  title={Onset of catalytic activity of gold clusters on titania with the appearance of nonmetallic properties},
  author={Valden and Lai and Goodman},
  volume={281 5383},
Gold clusters ranging in diameter from 1 to 6 nanometers have been prepared on single crystalline surfaces of titania in ultrahigh vacuum to investigate the unusual size dependence of the low-temperature catalytic oxidation of carbon monoxide. Scanning tunneling microscopy/spectroscopy (STM/STS) and elevated pressure reaction kinetics measurements show that the structure sensitivity of this reaction on gold clusters supported on titania is related to a quantum size effect with respect to the… 
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