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Tailored catalyst microenvironments for CO2 electroreduction to multicarbon products on copper using bilayer ionomer coatings

A Publisher Correction to this article was published on 24 November 2021

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Electrochemical carbon dioxide reduction (CO2R) provides a promising pathway for sustainable generation of fuels and chemicals. Copper (Cu) electrocatalysts catalyse CO2R to valuable multicarbon (C2+) products, but their selectivity depends on the local microenvironment near the catalyst surface. Here we systematically explore and optimize this microenvironment using bilayer cation- and anion-conducting ionomer coatings to control the local pH (via Donnan exclusion) and CO2/H2O ratio (via ionomer properties), respectively. When this tailored microenvironment is coupled with pulsed electrolysis, further enhancements in the local ratio of CO2/H2O and pH are achieved, leading to selective C2+ production, which increases by 250% (with 90% Faradaic efficiency and only 4% H2) compared with static electrolysis over bare Cu. These results underscore the importance of tailoring the catalyst microenvironment as a means of improving overall performance in electrochemical syntheses.

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Fig. 1: Morphological and compositional analysis on ionomer-coated Cu.
Fig. 2: CO2R using ionomer-coated Cu.
Fig. 3: Effect of cation identity on CO2R using ionomer-coated Cu.
Fig. 4: Effect of stacking ionomer layers.
Fig. 5: Schematic depiction of enhanced CO2R using ionomers.
Fig. 6: Synergy between microenvironment using ionomer layers and pulsed CO2 electrolysis.

Data availability

All data for this study are available in the Supplementary Information. Source data are provided with this paper.

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This work was supported by the Joint Center for Artificial Photosynthesis, a DOE Energy Innovation Hub, supported through the Office of Science of the US Department of Energy under award no. DE-SC0004993 and Liquid Sunlight Alliance, which is supported by the US Department of Energy, Office of Science, Office of Basic Energy Sciences, Fuels from Sunlight Hub under award no. DE-SC0021266.

Author information




C.K. performed catalyst preparation, electrochemical experiments, characterizations and data interpretation. J.C.B. performed data interpretation and theoretical calculations. X.L. performed sample preparation and measurement for water uptake on ionomer film. J.K.C. performed X-ray photoemission spectroscopy analysis of ionomer-coated Cu. A.T.B., A.Z.W. and A.K. supervised the project. All authors discussed the results and participated in the preparation of the manuscript.

Corresponding author

Correspondence to Alexis T. Bell.

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The authors declare no competing interests.

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Peer review information Nature Energy thanks Feng Jiao and the other, anonymous, reviewers for their contribution to the peer review of this work.

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Supplementary Information

Supplementary Figs. 1–17, Tables 1–3, Notes 1–6 and refs. 1–8.

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Kim, C., Bui, J.C., Luo, X. et al. Tailored catalyst microenvironments for CO2 electroreduction to multicarbon products on copper using bilayer ionomer coatings. Nat Energy 6, 1026–1034 (2021).

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