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Electrocatalytic reduction of protons to dihydrogen by the cobalt tetraazamacrocyclic complex [Co(N₄H)Cl₂]⁺: mechanism and benchmarking of performances.

ABSTRACT: The cobalt tetraazamacrocyclic [Co(N₄H)Cl₂]⁺ complex is becoming a popular and versatile catalyst for the electrocatalytic evolution of hydrogen, because of its stability and superior activity in aqueous conditions. We present here a benchmarking of its performances based on the thorough analysis of cyclic voltammograms recorded under various catalytic regimes in non-aqueous conditions allowing control of the proton concentration. This allowed a detailed mechanism to be proposed with quantitative determination of the rate-constants for the various protonation steps, as well as identification of the amine function of the tetraazamacrocyclic ligand to act as a proton relay during H₂ evolution.

SUBMITTER: Li CB

PROVIDER: S-EPMC8691182 | biostudies-literature |

REPOSITORIES: biostudies-literature

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