Microscopic CO Diffusion on Pt (111) by Time-Resolved Surface Infrared Spectroscopy

Adsorbate mobilities reflect self and substrate interactions and govern the kinetics of many surface reactions. For CO diffusion on Pt (111), previous measurements using field emission and He scattering have reported activation barriers of 14 and 7 kcal/mole, respectively. We have used newly developed time-resolved surface infrared/pulsed molecular beam methods to measure directly CO diffusion on stepped Pt(111) surfaces.