Effect of Pt cocatalyst in Pt/TiO2 studied by in situ FTIR of CO adsorption

In situ transmission infrared spectroscopy was used to study the role of Pt cocatalyst in Pt/TiO2 using CO as a probe molecule. An 11 cm−1 redshift of CO adsorbed on Pt/TiO2 was observed under irradiation in the absence of changes in the CO coverage or sample temperature. In contrast, no CO shift was detected on Pt/Al2O3. This indicates that the redshift of the CO adsorption peak is due to the photogenerated electron transfer from TiO2 to Pt, and this accounts for the increased photocatalytic activity by the loaded Pt cocatalyst.

Graphical AbstractA band at 2079 cm−1 was attributed to CO adsorbed on Pt nanoparticle, while the peak shifted to 2068 cm−1 after UV irradiation. CO peak redshift indicates photogenerated electron transfer from TiO2 to Pt particles.Figure optionsDownload as PowerPoint slide