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Exploring the ternary interactions in Cu-ZnO-ZrO₂ catalysts for efficient CO₂ hydrogenation to methanol.

ABSTRACT: The synergistic interaction among different components in complex catalysts is one of the crucial factors in determining catalytic performance. Here we report the interactions among the three components in controlling the catalytic performance of Cu-ZnO-ZrO₂ (CZZ) catalyst for CO₂ hydrogenation to methanol. The in situ diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) measurements under the activity test pressure (3 MPa) reveal that the CO₂ hydrogenation to methanol on the CZZ catalysts follows the formate pathway. Density functional theory (DFT) calculations agree with the in situ DRIFTS measurements, showing that the ZnO-ZrO₂ interfaces are the active sites for CO₂ adsorption and conversion, while the presence of metallic Cu is also necessary to facilitate H₂ dissociation and to provide hydrogen resource. The combined experiment and DFT results reveal that tuning the interaction between ZnO and ZrO₂ can be considered as another important factor for designing high performance catalysts for methanol generation from CO₂.

SUBMITTER: Wang Y

PROVIDER: S-EPMC6411953 | biostudies-literature |

REPOSITORIES: biostudies-literature

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Cu2In alloy-embedded ZrO2 catalysts for efficient CO2 hydrogenation to methanol: promotion of plasma modification.

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