First principles adaptive kinetic Monte Carlo calculations of catalytic reactions at supported nanoparticles
EMSL Project ID
25428
Abstract
The goal of this project is to use density functional theory calculations to discover the mechanisms and rates of catalytic reactions on oxide supported metal surfaces and nanoparticles. The focus will be on reactions that are important for hydrogen production, including steam reforming of methanol, the water-gas shift reaction, and preferential oxidation of CO. A comparison of rate limiting steps will be made between crystal facets of Pt and Cu, and compared with nanoparticles of these metals supported on CeO2. The specific aim of this proposal is to implement and apply new computational methodology at the EMSL for finding reaction mechanisms and using the calculated rates to simulate the reaction dynamics of adsorbed molecules. To do this, we will use the dimer min-mode following saddle point finding method [1], implemented in the Vienna Ab-Initio Software Package (VASP), to search for possible reaction mechanism. These calculations will not be restricted to expected reaction mechanisms; instead, through many random searches, the method will automatically discover which reactions are most likely to happen. The submission of these calculations, as well as the collection of the resulting data will be done with an automated perl script [2]. When this script learns about the possible reaction mechanisms, it does a kinetic Monte Carlo step, and the saddle point finding process is repeated. In this way, the unbiased reaction dynamics of the molecules will be simulated, and the mechanism of catalytic reactions at nanoparticles is explored.[1] See http://theory.cm.utexas.edu/vtsttools/dimer/
[2] See http://theory.cm.utexas.edu/vtsttools/akmc/
Project Details
Project type
Large-Scale EMSL Research
Start Date
2007-05-22
End Date
2010-09-30
Status
Closed
Released Data Link
Team
Principal Investigator
Team Members
Related Publications
Lijun Xu, Donghai Mei, and Graeme Henkelman "Adaptive kinetic Monte Carlo simulation of methanol decomposition on Cu(100)" J. Chem. Phys. (2009) under review.
L. Xu, D. Mei, and G. Henkelman Adaptive kinetic Monte Carlo simulation of methanol decomposition on Cu(100), J. Chem. Phys. 131, 244520 (2010).
Mei D, L Xu, and GA Henkelman. 2008. "Dimer Saddle Point Searches to Determine the Reactivity of Formate on Cu(111)." Journal of Catalysis 258(1):44-51.