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Redox Replacement of Silver on MOF-Derived Cu/C Nanoparticles on Gas Diffusion Electrodes for Electrocatalytic CO₂ Reduction.

ABSTRACT: Bimetallic tandem catalysts have emerged as a promising strategy to locally increase the CO flux during electrochemical CO₂ reduction, so as to maximize the rate of conversion to C-C-coupled products. Considering this, a novel Cu/C-Ag nanostructured catalyst has been prepared by a redox replacement process, in which the ratio of the two metals can be tuned by the replacement time. An optimum Cu/Ag composition with similarly sized particles showed the highest CO₂ conversion to C₂₊ products compared to non-Ag-modified gas-diffusion electrodes. Gas chromatography and in-situ Raman measurements in a CO₂ gas diffusion cell suggest the formation of top-bound linear adsorbed *CO followed by consumption of CO in the successive cascade steps, as evidenced by the increasingνC-H bands. These findings suggest that two mechanisms operate simultaneously towards the production of HCO₂ H and C-C-coupled products on the Cu/Ag bimetallic surface.

SUBMITTER: Sikdar N

PROVIDER: S-EPMC9304169 | biostudies-literature |

REPOSITORIES: biostudies-literature

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