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 Features »

Subject Areas

NanophysicsChemical PhysicsMaterials Science

Previous Synopsis

Next Synopsis

Related Articles

Synopsis: Protons in the Fast Lane
Energy Research

Synopsis: Protons in the Fast Lane

A proposed graphene-based material could offer speedy transport of protons without the need for water. Read More »

Synopsis: A Crystal Ball for 2D Materials
Materials Science

Synopsis: A Crystal Ball for 2D Materials

Researchers predict new two-dimensional materials whose structures differ from their three-dimensional counterparts. Read More »

Viewpoint: Electron Pulses Made Faster Than Atomic Motions
Atomic and Molecular Physics

Viewpoint: Electron Pulses Made Faster Than Atomic Motions

Electron pulses have shattered the 10-femtosecond barrier at which essentially all atomic motion is frozen in materials. Read More »

More Articles