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The active sites of Cu-ZnO catalysts for water gas shift and CO hydrogenation reactions.

ABSTRACT: Cu-ZnO-Al₂O₃ catalysts are used as the industrial catalysts for water gas shift (WGS) and CO hydrogenation to methanol reactions. Herein, via a comprehensive experimental and theoretical calculation study of a series of ZnO/Cu nanocrystals inverse catalysts with well-defined Cu structures, we report that the ZnO-Cu catalysts undergo Cu structure-dependent and reaction-sensitive in situ restructuring during WGS and CO hydrogenation reactions under typical reaction conditions, forming the active sites of Cu_Cu(100)-hydroxylated ZnO ensemble and Cu_Cu(611)Zn alloy, respectively. These results provide insights into the active sites of Cu-ZnO catalysts for the WGS and CO hydrogenation reactions and reveal the Cu structural effects, and offer the feasible guideline for optimizing the structures of Cu-ZnO-Al₂O₃ catalysts.

SUBMITTER: Zhang Z

PROVIDER: S-EPMC8282834 | biostudies-literature |

REPOSITORIES: biostudies-literature

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