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Identifying Structure-Selectivity Correlations in the Electrochemical Reduction of CO₂ : A Comparison of Well-Ordered Atomically Clean and Chemically Etched Copper Single-Crystal Surfaces.

ABSTRACT: The identification of the active sites for the electrochemical reduction of CO₂ (CO₂ RR) to specific chemical products is elusive, owing in part to insufficient data gathered on clean and atomically well-ordered electrode surfaces. Here, ultrahigh vacuum based preparation methods and surface science characterization techniques are used with gas chromatography to demonstrate that subtle changes in the preparation of well-oriented Cu(100) and Cu(111) single-crystal surfaces drastically affect their CO₂ RR selectivity. Copper single crystals with clean, flat, and atomically ordered surfaces are predicted to yield hydrocarbons; however, these were found experimentally to favor the production of H₂ . Only when roughness and defects are introduced, for example by electrochemical etching or a plasma treatment, are significant amounts of hydrocarbons generated. These results show that structural and morphological effects are the key factors determining the catalytic selectivity of CO₂ RR.

SUBMITTER: Scholten F

PROVIDER: S-EPMC8457179 | biostudies-literature |

REPOSITORIES: biostudies-literature

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