Synopsis: Training Catalytic Atoms to Stop Fidgeting

Single atoms deposited on an iron oxide surface provide a valuable model system for studying catalysis.
Synopsis figure
Courtesy of Z. Novotný and M. Schmid/Vienna University of Technology

Much of modern industrial chemistry relies on catalysts to drive useful reactions toward desired end products and increased yields. What makes these catalysts successful becomes clearer only with the ability to identify and analyze individual atoms on oxide surfaces, so having model systems to explore the chemistry and physics of surfaces is crucial. In a paper in Physical Review Letters, Zbynĕk Novotný and colleagues at the Vienna University of Technology, Austria, report their development of thermally stable arrays of gold atoms on iron oxide that may be ideal for answering key questions in catalysis.

Previous work has hinted at a size effect in catalysis: as clusters of catalytic metal atoms get smaller and smaller, they become more chemically active. Taken to the limit, individual atoms may be the most active, but studying this behavior demands a stable, well-characterized combination of atom and surface. Typically, however, gold atoms are highly mobile on these kinds of substrates and researchers have to cool them to cryogenic temperatures to hold them steady, making investigation under realistic conditions difficult.

Novotný et al. find that gold atoms sit comfortably on single crystals of Fe3O4 (magnetite) cut to present a particular surface structure at temperatures as high as 400C. Owing to charge ordering in the iron oxide, the surface acquires a lateral electronic structure that may stabilize the gold atoms, along with several other adsorbed atoms studied by the researchers. This suggests that the team has discovered a model system that may be universally applicable to detailed investigations of small cluster catalysis under actual reaction conditions. – David Voss


More Announcements »

Subject Areas

NanophysicsChemical PhysicsMaterials Science

Previous Synopsis

Next Synopsis

Related Articles

Synopsis: Acoustic Trigger For Earthquakes

Synopsis: Acoustic Trigger For Earthquakes

Numerical simulations support the idea that acoustic waves can trigger earthquakes by reducing friction between the rocks within a fault. Read More »

Focus: Shaking Cleans Nanoscale Surface

Focus: Shaking Cleans Nanoscale Surface

An oscillatory motion dramatically reduces the number of contaminant molecules at the interface between two surfaces. Read More »

Synopsis: Multiferroic Surprise

Synopsis: Multiferroic Surprise

Electric and magnetic polarization are spontaneously produced in an unlikely material—one with a highly symmetric crystal structure. Read More »

More Articles