Catalytic Model Systems and Surface Reactivity Studied at the Atomic Scale by High-resolution, Fast-scanning STM
Lecture by Flemming Besenbacher
Interdisciplinary Nanoscience Center
University of Aarhus
Tuesday, February 26, 2008
Room 1610 Engineering Hall
Refreshments at 3:45 p.m.
Lecture at 4:00 p.m.
For decades, single-crystal surfaces have been studied under ultrahigh vacuum conditions as model systems for elementary surface processes underlying phenomena such as heterogeneous catalysis, epitaxial growth, and corrosion. This "surface science approach" has contributed substantially to our understanding of the processes involved in catalysis, and has in some cases led to the design of improved catalysts. Recently, much attention has been paid to the so-called gaps between surface science and industrial catalysis: the pressure gap which arises because of the pressure difference between UHV base pressures and atmospheric pressure; and the structural gap relating to the difference in reactivity on single-crystal surfaces, as opposed to nanoclusters.
In this talk I will show how one can use the unique capabilities of Scanning Tunneling Microscopy to reveal fundamental processes in relation to catalysis. STM has proven to be a fascinating and powerful technique for revealing the atomic-scale realm of matter. The unique Aarhus STM allows us to record time-resolved, high-resolution STM images, visualized in the form of STM movies (see www.phys.au.dk/spm). I will show how we can obtain quantitative information on and unique insight into diffusion and transport phenomena associated with surface processes and nanostructures, and how atomic-scale studies may lead to design of improved catalysts.