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Synthesis of Metal Nanoparticles Supported on Carbon Nanotube with Doped Co and N Atoms and its Catalytic Applications in Hydrogen Production
Published on: December 6, 2021
Carbon monoxide dissociation on Rh nanopyramids.
F Buatier de Mongeot1, A Toma, A Molle
1Dipartimento di Fisica, Università di Genova, Via Dodecaneso 33, 16146 Genoa, Italy.
Physical Review Letters
|October 10, 2006
Summary
Rh(110) nanopyramids enhance carbon monoxide (CO) dissociation, a reaction hindered on flat surfaces. Specific undercoordinated step edges on these nanostructures are identified as key sites for breaking the CO molecular bond.
Area of Science:
- Surface Science
- Catalysis
- Materials Science
Background:
- Carbon monoxide (CO) dissociation is crucial in many catalytic processes.
- CO dissociation is typically inhibited on flat Rh(110) surfaces.
- Nanostructured surfaces can exhibit unique reactivity compared to flat surfaces.
Purpose of the Study:
- To investigate CO dissociation on rhomboidal faceted nanopyramids produced on Rh(110).
- To identify the specific sites responsible for CO dissociation on these nanostructures.
- To compare the reactivity of nanopyramids with flat Rh(110) terraces.
Main Methods:
- Production of Rh(110) nanopyramids via controlled ion irradiation.
- High-resolution core-level spectroscopy for surface analysis.
- Investigation of nanostructures with varying step distributions.
Main Results:
- Rh(110) nanopyramids show significantly enhanced CO dissociation efficiency.
- CO dissociation is largely inhibited on flat Rh(110) terraces.
- Undercoordinated (n=6) step edges along [11[over ]2] directions were identified as active sites for CO bond disruption.
- CO was observed to adsorb in an on-top configuration at these active sites.
Conclusions:
- Rh(110) nanopyramids are highly efficient for CO dissociation.
- The specific morphology and step edge configurations of nanopyramids are critical for catalytic activity.
- Undercoordinated step edges play a key role in facilitating CO bond cleavage.
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