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Updated: May 18, 2026
Catalytic Reactions at Amine-Stabilized and Ligand-Free Platinum Nanoparticles Supported on Titania During Hydrogenation of Alkenes and Aldehydes
Published on: June 24, 2022
Capping ligands as selectivity switchers in hydrogenation reactions
Soon Gu Kwon1, Galyna Krylova, Aslihan Sumer
1Center for Nanoscale Materials, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, Illinois 60439, USA.
Surface modification of platinum and cobalt/platinum nanoparticles with primary alkylamines dramatically enhances selectivity for alkene production in alkyne hydrogenation reactions. This modification controls catalyst activity by tuning ligand-metal interactions.
Area of Science:
- Catalysis
- Nanomaterials Science
- Surface Chemistry
Background:
- Alkyne hydrogenation is crucial for producing valuable alkenes.
- Controlling selectivity in nanoparticle catalysis remains a challenge.
- Surface modification offers a route to tune catalyst performance.
Purpose of the Study:
- To investigate the impact of surface ligands on platinum (Pt) and cobalt/platinum (Co/Pt) nanoparticle catalysts.
- To elucidate the mechanism by which surface modification influences selectivity and activity in alkyne hydrogenation.
- To establish a general explanation for ligand effects on nanocatalyst performance.
Main Methods:
- Experimental studies involving Pt and Co/Pt nanoparticles.
- Computational modeling to understand adsorption energetics.
- Systematic variation of surface ligand coverage and type.
Main Results:
- Addition of primary alkylamines to Pt and CoPt(3) nanoparticles increased alkene selectivity from 0% to over 90% with near-complete alkyne conversion.
- Selectivity is governed by the balance between alkene and ligand adsorption energies at the nanoparticle surface.
- Higher ligand coverage leads to ligand dominance in adsorption, preventing over-hydrogenation to alkanes.
Conclusions:
- Surface modification with primary alkylamines is a highly effective strategy for achieving selective alkyne hydrogenation to alkenes.
- The adsorption energetics of surface ligands relative to reaction intermediates dictates catalyst selectivity and activity.
- This work provides a generalizable principle for designing nanocatalysts for selective hydrogenation reactions.
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