Redox properties of supported copper catalysts studied in liquid and gas phase by in situ ATR-IR and XAS

Redox properties of copper nanoparticles supported on Al2O3, TiO2 and SiO2 in the liquid (presence of solvent) and gas phase have been investigated by means of in situ Attenuated Total Reflection Infrared spectroscopy (ATR-IR) and in situ X-ray absorption spectroscopy (XAS) in combination with CO adsorption. Using CO and H2 as a reducing agent, the presence of the solvent was found to facilitate reduction of the copper constituent at lower temperatures than in the gas phase. The reduction behavior measured in the presence of the solvent was found to be correlated to the activity of the catalysts in the anaerobic oxidation of 3-octanol.