Abstract
The coverage of surface adsorbates influences both the number and types of sites available for catalytic reactions at a heterogeneous surface, but accounting for adsorbate-adsorbate interactions and understanding their implications on observed rates remain challenges for simulation. Here, we demonstrate the use of a density functional theory (DFT)-parameterized cluster expansion (CE) to incorporate accurate adsorbate-adsorbate interactions into a surface kinetic model. The distributions of adsorbates and reaction sites at a metal surface as a function of reaction conditions are obtained through Grand Canonical Monte Carlo simulations on the CE Hamiltonian. Reaction rates at those sites are obtained from the CE through a DFT-parameterized Brønsted- Evans-Polyani (BEP) relationship. The approach provides ready access both to steady-state rates and rate derivatives and further provides insight into the microscopic factors that influence observed rate behavior. We demonstrate the approach for steady-state O 2 dissociation at an O-covered Pt (1 1 1) surface - a model for catalytic NO oxidation at this surface - and recover apparent activation energies and rate orders consistent with experiment.
Original language | English (US) |
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Pages (from-to) | 88-94 |
Number of pages | 7 |
Journal | Journal of Catalysis |
Volume | 286 |
DOIs | |
State | Published - Feb 2012 |
Keywords
- Adsorbate-adsorbate interactions
- Cluster expansion
- DFT
- NO oxidation kinetics
- O dissociation
- Pt (1 1 1)
- Rate laws
ASJC Scopus subject areas
- Catalysis
- Physical and Theoretical Chemistry