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Nuclear Quantum Effects in OH*/OD* Formation Kinetics on Pd(332): A Ring-Polymer Molecular Dynamics Study
Liang Zhang1, Chen Li1, Michael Schwarzer2,3
1Department of Chemistry and Chemical Biology, Center for Computational Chemistry, University of New Mexico, Albuquerque, New Mexico 87131, United States.
The Journal of Physical Chemistry Letters
|October 20, 2025
Summary
This study accurately calculates reaction rates for heterogeneous catalysis, specifically hydrogen oxidation on palladium surfaces. Findings confirm experimental data and reveal significant quantum effects even at higher temperatures.
Area of Science:
- Heterogeneous catalysis
- Surface chemistry
- Computational chemistry
Background:
- Understanding reaction kinetics is crucial for heterogeneous catalysis.
- Surface reaction rates are dependent on reactant coverage.
- Palladium-catalyzed hydrogen oxidation is a key industrial process.
Purpose of the Study:
- To accurately calculate reaction rates for a key step in Pd-catalyzed hydrogen oxidation.
- To investigate the coverage-dependence of surface reactions.
- To explore nuclear quantum effects in the reaction.
Main Methods:
- Ring-polymer molecular dynamics (RPMD) simulations were employed.
- The study focused on the formation of OH from adsorbed H and O on Pd(332).
- Simulations were performed at both high and low coverages.
Main Results:
- Calculated rate coefficients align with recent experimental data.
- Significant nuclear quantum effects were observed.
- These effects persist even at relatively high temperatures.
Conclusions:
- Ring-polymer molecular dynamics provides accurate rate coefficients for surface reactions.
- Nuclear quantum effects play a substantial role in hydrogen oxidation kinetics on palladium.
- Coverage significantly influences reaction rates in heterogeneous catalysis.
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