Visualizing catalyst heterogeneity by a multifrequencial oscillating reaction
Journal article, 2018

It is well documented that different surface structures of catalytically active metals may exhibit different catalytic properties. This is typically examined by comparing the catalytic activities and/or selectivities of various well-defined smooth and stepped/kinked single crystal surfaces. Here we report the direct observation of the heterogeneity of active polycrystalline surfaces under reaction conditions, which is manifested by multifrequential oscillations during hydrogen oxidation over rhodium, imaged in situ by photoemission electron microscopy. Each specific surface structure, i.e. the crystallographically different µm-sized domains of rhodium, exhibits an individual spiral pattern and oscillation frequency, despite the global diffusional coupling of the surface reaction. This reaction behavior is attributed to the ability of stepped surfaces of high-Miller-index domains to facilitate the formation of subsurface oxygen, serving as feedback mechanism of the observed oscillations. The current experimental findings, backed by microkinetic modeling, may open an alternative approach towards addressing the structure-sensitivity of heterogeneous surfaces.

Heterogeneous catalysis

Author

M. Datler

Vienna University of Technology

Y. Suchorski

Vienna University of Technology

I. Bespalov

Vienna University of Technology

J. Zeininger

Vienna University of Technology

M. Stoger-Pollach

Vienna University of Technology

J. Bernardi

Vienna University of Technology

Henrik Grönbeck

Chalmers, Physics, Chemical Physics

G. Rupprechter

Vienna University of Technology

Nature Communications

2041-1723 (ISSN)

Vol. 9 600

Subject Categories

Inorganic Chemistry

Materials Chemistry

Other Chemistry Topics

Driving Forces

Sustainable development

Areas of Advance

Nanoscience and Nanotechnology (2010-2017)

Energy

Materials Science

Roots

Basic sciences

Infrastructure

C3SE (Chalmers Centre for Computational Science and Engineering)

DOI

10.1038/s41467-018-03007-3

PubMed

29426883

More information

Latest update

8/22/2019