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Updated: May 16, 2026
14:21
Performing In Situ Closed-Cell Gas Reactions in the Transmission Electron Microscope
Published on: July 24, 2021
Catalytic hot-spots in CO oxidation resolved by operando electron microscopy
Christian F Elkjær1,2, Sebastian P F Jespersen1,2, Søren B Vendelbo3
1Topsoe A/S, Haldor Topsøes Allé 1, DK-2800 Kgs. Lyngby, Denmark.
Faraday Discussions
|May 14, 2026
Summary
Dense nanoparticle packing creates catalytic hot-spots for sustained CO oxidation. This collective behavior, driven by nanoparticle entanglement, enhances catalytic functions, offering new engineering pathways.
Area of Science:
- Materials Science
- Chemical Engineering
- Catalysis
Background:
- Catalytic reactions are often explained by individual nanoparticle properties.
- The collective behavior of densely packed nanoparticles is understudied.
Purpose of the Study:
- To investigate the emergent collective behavior of nanoparticle ensembles during catalysis.
- To understand how nanoparticle loading impacts catalytic activity and spatial distribution.
Main Methods:
- Utilized *operando* transmission electron microscopy and spectroscopy.
- Examined carbon monoxide (CO) oxidation over platinum (Pt) nanoparticles in a gas-flow reactor.
Main Results:
- High nanoparticle loading regions formed catalytic hot-spots with sustained CO conversion.
- Low-loaded regions showed gradual conversion downstream.
- Hot-spots correlated with specific shape-activity relationships and thermally mediated entanglement.
Conclusions:
- Thermally mediated entanglement in densely packed nanoparticles drives self-sustained catalytic activity.
- Identifying nanoparticle entanglement enables engineering for enhanced spatial catalytic functionalities.
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