In-situ studies of catalytic reactions over well-defined model catalysts

Atomic-scale understanding of the elementary processes occurring at catalytic surfaces and interfaces requires the development of surface science techniques, that could measure the surface structure, electronic properties and reaction intermediates on catalytic materials during the reaction and at the spatial and temporal limit. In the past decades, tremendous efforts have been dedicated to developing surface science techniques that could be employed for in-situ studies of catalytic systems under ambient pressures, and as such to bridge the pressure gap that has generally concerned the catalysis community. In this chapter, we review progress in in-situ and ambient pressure studies of catalytic reactions over well-defined model catalytic systems in the past decade, using scanning tunnelling microscopy (STM), X-ray photoelectron spectroscopy (XPS) and Infrared reflection adsorption spectroscopy (IRAS). This progress has enabled molecular understanding of chemical processes occurring at catalytically active surfaces and interfaces. A brief outlook on developments in combining microscopic and spectroscopic surface techniques is also given, that could open a new horizon for catalytic science.