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Updated: Jun 30, 2026
10:19
Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation
Published on: July 18, 2017
Shape changes of supported Rh nanoparticles during oxidation and reduction cycles
P Nolte1, A Stierle, N Y Jin-Phillipp
1Max-Planck-Institut für Metallforschung, Heisenbergstrasse 3, D-70569 Stuttgart, Germany.
Science (New York, N.Y.)
|September 20, 2008
Summary
Rhodium nanoparticles change shape during oxidation, a transformation reversed by carbon monoxide. This discovery offers insights into nanoparticle behavior during catalytic reactions.
Area of Science:
- Heterogeneous catalysis
- Materials science
- Surface chemistry
Background:
- Understanding nanoparticle shape changes during catalytic reactions is crucial for fundamental catalysis knowledge.
- Oxidation and reduction cycles significantly impact nanoparticle structure and reactivity.
Purpose of the Study:
- To investigate the oxygen-induced shape transformation of rhodium nanoparticles on magnesium oxide substrates.
- To explore the mechanism behind this shape change and its reversal.
Main Methods:
- High-resolution in situ X-ray diffraction
- Transmission electron microscopy
- Wulff analysis
Main Results:
- Rhodium nanoparticles undergo shape transformation on magnesium oxide (001) due to oxygen exposure.
- Carbon monoxide exposure at 600 Kelvin reverses this shape transformation.
- The phenomenon is driven by the formation of a surface oxide layer (oxygen-rhodium-oxygen) on rhodium nanofacets.
Conclusions:
- The study provides experimental insight into nanoparticle dynamics during catalytic cycles.
- This understanding is vital for designing and developing advanced heterogeneous catalysts with improved performance.
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