Related Experiment Video
Updated: May 16, 2025
10:19
Synthesis and Testing of Supported Pt-Cu Solid Solution Nanoparticle Catalysts for Propane Dehydrogenation
Published on: July 18, 2017
11.9K
Formation of hydrided Pt-Ce-H sites in efficient, selective oxidation catalysts
Ji Yang1, Lorenz J Falling2, Siyang Yan3
1Energy Storage and Distributed Resources Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.
Science (New York, N.Y.)
|April 3, 2025
Summary
Modified single-atom catalysts show enhanced reactivity and selectivity for key reactions. These advanced platinum-based sites significantly boost carbon monoxide oxidation and propane dehydrogenation rates.
Area of Science:
- Catalysis
- Materials Science
- Surface Chemistry
Background:
- Single-atom site catalysts offer high efficiency in chemical reactions.
- Platinum on ceria (Pt/CeO2) is a key catalyst system.
- Modifying single-atom sites can further enhance catalytic performance.
Purpose of the Study:
- To modify Pt1/CeO2 single-atom sites by incorporating molecular groups and oxygen vacancies.
- To investigate the enhanced reactivity and selectivity of these modified sites.
- To elucidate the atomic structure and reaction mechanisms of the new catalytic sites.
Main Methods:
- Synthesis of modified Pt1/CeO2 single-atom catalysts.
- In situ and ex situ spectroscopy for atomic structure determination.
- Theoretical calculations to understand reaction steps and mechanisms.
Main Results:
- Developed hydrided (Pt2+-Ce3+Hδ-) and hydroxylated (Pt2+-Ce3+OH) single-atom sites.
- Achieved a ninefold increase in reaction rate for carbon monoxide oxidation.
- Improved propylene selectivity by 2.3-fold in oxidative dehydrogenation of propane.
Conclusions:
- Modified single-atom sites exhibit superior catalytic activity and selectivity compared to previous designs.
- The combination of molecular groups and oxygen vacancies is crucial for enhanced performance.
- Spectroscopic and theoretical methods successfully characterized the novel catalytic sites and their mechanisms.
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