Surface Physics
The Dance of the Atoms
Catalysts can fail when surface atoms start moving around.
Prof. Ulrike Diebold
Theories about this effect have been discussed for years, but the researchers in Vienna have now literally observed the clustering of the atoms in real time. "We are using palladium atoms on an extremely clean iron-oxide surfaces in an ultra high vacuum chamber. For several hours, we take pictures of the surface with a scanning tunneling microscope", Gareth Parkinson explains. These pictures are made into a movie that enables the researchers to track the paths of individual atoms.
Zbynek Novotny and Gareth Parkinson
With this new method of watching clustering in real time under the microscope, the mechanisms involved can be studied in detail: "We discovered that OH groups on the surface can suppress the clustering effect", Parkinson continues. If the carbon monoxide/palladium couples do not encounter each other, but instead find an OH group, they get trapped and cannot form a cluster. Therefore a future hydroxyl coating of surfaces could lead to a significant stability improvement in catalysts.
In 2013 alone, Prof. Diebold has not only received the Arthur W. Adamson Award for Distinguished Service in the Advancement of Surface Chemistry from the American Chemical Society - she is also the recipient of the 2013 Wittgenstein Award, the highest science award in Austria. Diebold had earned her doctorate at Vienna University of Technology in 1990, then she spent three years at Rutgers University in New Jersey. In 1993, she moved on to Tulane University in New Orleans, becoming a full professor. In 2010, Diebold was appointed to the TU's chair for surface science. (© Vienna University of Technology, Austrian Science Fund FWF)
