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Potential- and Buffer-Dependent Selectivity for the Conversion of CO₂ to CO by a Cobalt Porphyrin-Peptide Electrocatalyst in Water.

ABSTRACT: A semisynthetic electrocatalyst for carbon dioxide reduction to carbon monoxide in water is reported. Cobalt microperoxidase-11 (CoMP11-Ac) is shown to reduce CO₂ to CO with a turnover number of up to 32,000 and a selectivity of up to 88:5 CO:H₂. Higher selectivity for CO production is favored by a less cathodic applied potential and use of a higher pK _a buffer. A mechanistic hypothesis is presented in which avoiding the formation and protonation of a formal Co(I) species favors CO production. These results demonstrate how tuning reaction conditions impact reactivity toward CO₂ reduction for a biocatalyst previously developed for H₂ production.

SUBMITTER: Alvarez-Hernandez JL

PROVIDER: S-EPMC9724230 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature

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Potential- and Buffer-Dependent Selectivity for the Conversion of CO2 to CO by a Cobalt Porphyrin-Peptide Electrocatalyst in Water.

Alvarez-Hernandez Jose L JL Salamatian Alison A AA Han Ji Won JW Bren Kara L KL

ACS catalysis 20221116 23

A semisynthetic electrocatalyst for carbon dioxide reduction to carbon monoxide in water is reported. Cobalt microperoxidase-11 (CoMP11-Ac) is shown to reduce CO2 to CO with a turnover number of up to 32,000 and a selectivity of up to 88:5 CO:H2. Higher selectivity for CO production is favored by a less cathodic applied potential and use of a higher pK a buffer. A mechanistic hypothesis is presented in which avoiding the formation and protonation of a form ...[more]

PMID: 36504916

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