Title |
Mechanistic Aspects of the Water-Gas Shift Reaction on Isolated and Clustered Au Atoms on CeO2(110): A Density Functional Theory Study |
ID_Doc |
64734 |
Authors |
Song, WY; Hensen, EJM |
Title |
Mechanistic Aspects of the Water-Gas Shift Reaction on Isolated and Clustered Au Atoms on CeO2(110): A Density Functional Theory Study |
Year |
2014 |
Published |
Acs Catalysis, 4, 6 |
DOI |
10.1021/cs401206e |
Abstract |
Density functional theory was employed to study the water gas shift (WGS) reaction for two structural models namely, a single Au atom and a Au nanorod-supported on the (110) surface of ceria. The carboxyl mechanism involving a COOH intermediate is strongly preferred over the redox mechanism, which would require O- H bond cleavage of ceria-bound hydroxyl groups. Two candidate rate-controlling elementary reaction steps were identified in the carboxyl mechanism: oxygen vacancy formation and COOH formation from CO and OH adsorbed to Au and the ceria support, respectively. A reaction energy analysis shows that both steps are more favorable on clustered Au atoms than on a single Au atom. CO adsorption on a single Au atom is hindered because of its negative charge. Comparison to literature data shows that the WGS reaction is preferred for a gold cluster on the CeO2(110) surface over the CeO2(111) one because of the lower binding energy of OH on the former surface. These results are discussed in the light of a large number of experimental and theoretical studies of the Au/CeO2 catalyzed WGS reaction. |
Author Keywords |
density functional theory; Au/CeO2; WGS; active site; reaction mechanism; structure sensitivity |
Index Keywords |
Index Keywords |
Document Type |
Other |
Open Access |
Open Access |
Source |
Science Citation Index Expanded (SCI-EXPANDED) |
EID |
WOS:000337074700029 |
WoS Category |
Chemistry, Physical |
Research Area |
Chemistry |
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