| The design of better catalysts benefits from understanding the underlying surface chemistry of catalytic processes. In this thesis, three catalytic surface processes involving carbon monoxide have been investigated using combinations of experimental techniques, including infrared spectroscopy, microcalorimetry, reaction kinetics measurements, and theoretical calculations using density functional theory (DFT). In the first study, the surface of a Rh-Te alloy catalyst has been characterized with microcalorimetry, infrared spectroscopy, and DFT calculations using CO as a probe molecule. Information about the surface composition, reactivity and stability of the Rh-Te catalyst was obtained from the experimental and theoretical results.; In the next study, the adsorption of CO on hydroxyl-covered Pt surface has been studied by infrared spectroscopy to explore a reaction pathway for the water-gas shift reaction on Pt that has been predicted to be favorable by DFT calculations. The results of infrared spectroscopic studies were combined with the activation energy barriers predicted by DFT calculations to probe the mechanism of the water-gas shift reaction on Pt.; To obtain mechanistic understanding of the water-gas shift reaction and methanol reforming on Pt/Al2O3 catalysts in vapor and liquid phase, in situ attenuated total reflectance infrared (ATR-IR) spectroscopy has been applied to monitor Pt/Al2O 3 catalyst surfaces at elevated temperatures and pressures under conditions similar to reaction kinetics studies. The similarities and differences between vapor and liquid-phase methanol reforming and watergas shift were probed, and relations between the coverages of surface intermediates (e.g. CO) and reaction rates were obtained by combining the results of in situ ATR-IR studies with reaction kinetics measurements. |
