(461d) Solvent Effects on CO Adsorption and Oxidation on Pt/Al2O3 Using FTIR-ATR Spectroscopy

In heterogeneous catalysis, solvents can affect not only the reaction rate also the catalyst activity and selectivity. In this study, various solvents were chosen based on their polarity and Kamlet and Taft parameter (Ï€*, α, β ), including water, cyclohexane, oxane, tetrahydrofuran, toluene, pyridine, ethanol, acetic acid etc. Pt/Al₂O₃ consisting of 2-3 nm Pt nanoparticles was used in this study and the structural, electronic and catalytic properties as well as the Pt interaction with adsorbates (CO) were studied in the gas and liquid phases. The adsorption of CO on Pt was studied using FTIR-ATR (Fourier-Transform Infrared-Attenuated Total Reflection) spectroscopy in both the gas phase and liquid phase using an in-house built ATR cell. The effect of the solvent properties on the binding of CO to Pt nanoparticles, as reflected in the C-O vibrational frequency shift and peak characters (shape and intensity), will be presented. Additionally, the CO oxidation reaction was measured in the different solvents and the correlation between the solvent properties, C-O vibrational frequency and CO oxidation reaction rate will be discussed.