Uncovering Structure-Activity Relationships in Pt/CeO2 Catalysts for Hydrogen-Borrowing Amination
Tao Tong1,2, Mark Douthwaite1, Lu Chen2
1Cardiff Catalysis Institute, School of Chemistry, Cardiff University, Main Building, Park Place, CardiffCF10 3AT, U.K.
ACS Catalysis
|January 30, 2023
Summary
Platinum catalysts on ceria supports enable efficient hydrogen-borrowing amination of alcohols. Linear platinum species, formed via epitaxial deposition, are key to high catalytic performance in amine production.
Area of Science:
- Catalysis
- Materials Science
- Organic Chemistry
Background:
- Hydrogen-borrowing amination offers a sustainable pathway for amine synthesis from alcohols.
- Developing efficient and selective catalysts is crucial for advancing this atom-efficient reaction.
Purpose of the Study:
- To investigate how physicochemical properties of Platinum/Cerium Dioxide (Pt/CeO2) catalysts influence their performance in hydrogen-borrowing amination.
- To understand the role of the Pt precursor and CeO2 support characteristics on catalyst activity.
Main Methods:
- Systematic variation of experimental parameters during Pt/CeO2 catalyst preparation.
- Catalytic testing using the amination of cyclopentanol with cyclopentylamine as a model reaction.
- Characterization using aberration-corrected scanning transmission electron microscopy (STEM) and Density Functional Theory (DFT) calculations.
Main Results:
- Catalyst performance was strongly dependent on the Pt precursor and CeO2 support properties.
- The most active catalyst featured linearly structured Pt species, formed by epitaxial deposition on CeO2 [100] planes.
- DFT calculations confirmed that these linear Pt sites exhibit higher activity for cyclopentanol dehydrogenation than Pt clusters or nanoparticles.
Conclusions:
- Linear Pt species on CeO2 are highly effective for hydrogen-borrowing amination.
- Catalyst design principles for this reaction are elucidated, emphasizing the importance of specific Pt structures and support interactions.
- This work provides a foundation for developing advanced catalysts for atom-efficient amine synthesis.
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