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Alternative Pathway of CO₂ Hydrogenation by Lewis-Pair-Functionalized UiO-66 MOF Revealed by Metadynamics Simulations.

ABSTRACT: The reaction between H₂ and CO₂ catalyzed by an intramolecular frustrated Lewis pair, which is covalently bonded to a UiO-66 metal-organic framework (MOF), is considered in this work. Free energy surfaces (FESs) for this reaction are generated throughout finite-temperature density functional theory (DFT) metadynamics (MD) simulations. The simulated FESs indicate an alternative stepwise pathway for the hydrogenation of CO₂. Furthermore, indications of weaker binding of CO₂ than H₂ to the Lewis pair centers have been observed via metadynamics simulations. These findings were unknown from the results of static-DFT calculations, which proposed a concerted reduction of CO₂. The results of the present work may influence the design of new efficient heterogeneous Lewis pair (LP)-functionalized MOFs to catalyze capture and conversion of CO₂ to high-value chemicals.

SUBMITTER: Heshmat M

PROVIDER: S-EPMC8192054 | biostudies-literature | 2020 May

REPOSITORIES: biostudies-literature

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Alternative Pathway of CO2 Hydrogenation by Lewis-Pair-Functionalized UiO-66 MOF Revealed by Metadynamics Simulations.

Heshmat Mojgan M

The journal of physical chemistry. C, Nanomaterials and interfaces 20200501 20

The reaction between H2 and CO2 catalyzed by an intramolecular frustrated Lewis pair, which is covalently bonded to a UiO-66 metal-organic framework (MOF), is considered in this work. Free energy surfaces (FESs) for this reaction are generated throughout finite-temperature density functional theory (DFT) metadynamics (MD) simulations. The simulated FESs indicate an alternative stepwise pathway for the hydrogenation of CO2. Furthermore, indications of weaker bindi ...[more]

PMID: 34122685

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