Format

Send to

Choose Destination
Nano Lett. 2012 Jul 11;12(7):3621-6. doi: 10.1021/nl301318b. Epub 2012 Jun 8.

Multiscale modeling reveals poisoning mechanisms of MgO-supported Au clusters in CO oxidation.

Author information

1
Department of Chemical and Biomolecular Engineering and Center for Catalytic Science and Technology, University of Delaware, Newark, Delaware 19716, United States.

Abstract

Catalyst deactivation mechanisms on MgO-supported Au(6) clusters are studied for the CO oxidation reaction via first-principle kinetic Monte Carlo simulations and shown to depend on support vacancies. In defect-poor MgO or in the presence of a Mg vacancy, O(2) does not bind to the clusters and the catalyst is poisoned by CO. On Au clusters interacting with O vacancies of the support, O(2) can be chemisorbed and transient activity is observed. In this case, an unexpected catalyst "breathing" mechanism (restructuring) leads to carbonate formation and catalyst deactivation, rationalizing several experimental observations. Our study underscores the importance of the cluster's charge state and dynamics on catalytic activity.

PMID:
22668206
DOI:
10.1021/nl301318b

Supplemental Content

Full text links

Icon for American Chemical Society
Loading ...
Support Center