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Deciphering nanoconfinement effects on molecular orientation and reaction intermediate by single molecule imaging.

ABSTRACT: Nanoconfinement could dramatically change molecular transport and reaction kinetics in heterogeneous catalysis. Here we specifically design a core-shell nanocatalyst with aligned linear nanopores for single-molecule studies of the nanoconfinement effects. The quantitative single-molecule measurements reveal unusual lower adsorption strength and higher catalytic activity on the confined metal reaction centres within the nanoporous structure. More surprisingly, the nanoconfinement effects on enhanced catalytic activity are larger for catalysts with longer and narrower nanopores. Experimental evidences, including molecular orientation, activation energy, and intermediate reactive species, have been gathered to provide a molecular level explanation on how the nanoconfinement effects enhance the catalyst activity, which is essential for the rational design of highly-efficient catalysts.

SUBMITTER: Dong B

PROVIDER: S-EPMC6811571 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Deciphering nanoconfinement effects on molecular orientation and reaction intermediate by single molecule imaging.

Dong Bin B Pei Yuchen Y Mansour Nourhan N Lu Xuemei X Yang Kai K Huang Wenyu W Fang Ning N

Nature communications 20191023 1

Nanoconfinement could dramatically change molecular transport and reaction kinetics in heterogeneous catalysis. Here we specifically design a core-shell nanocatalyst with aligned linear nanopores for single-molecule studies of the nanoconfinement effects. The quantitative single-molecule measurements reveal unusual lower adsorption strength and higher catalytic activity on the confined metal reaction centres within the nanoporous structure. More surprisingly, the nanoconfinement effects on enhan ...[more]

PMID: 31645571

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