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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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