Identifying and alleviating the durability challenges in membrane-electrode-assembly devices for high-rate co electrolysis

ABSTRACT CO electrolysis (COE) has emerged as an important alternative technology to couple with other sustainable techniques for transitioning towards a carbon-neutral future. A large

challenge for the deployment of high-rate COE is the limited durability of membrane-electrode assembly (MEA) devices. Here, by using an operando wide-angle X-ray scattering technique and

monitoring the change of electrolyte, we identified several degradation mechanisms of the MEA during high-rate COE. Cathodic gas-diffusion electrode (GDE) flooding and Ir contaminants

(crossover from anode) are two main issues causing excessive hydrogen evolution, which can be partly alleviated by increasing the polytetrafluoroethylene content in GDEs and using an

alkaline stable Ni-based anode. During long-term stability, the dynamic evolution of anolyte became the main issue: the pH would continuously drop due to cathodic acetate formation and

anodic ethanol oxidation. By compensating for this issue, we maintained a Faradaic efficiency of C2+ products at more than 70% for 136 hours. Access through your institution Buy or subscribe

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ULTRAMICROPOROUS ANION-EXCHANGE MEMBRANE ENABLES LONG-TERM OPERATION IN ELECTROCHEMICAL ENERGY DEVICES Article Open access 12 May 2023 A SCALABLE MEMBRANE ELECTRODE ASSEMBLY ARCHITECTURE FOR

EFFICIENT ELECTROCHEMICAL CONVERSION OF CO2 TO FORMIC ACID Article Open access 22 November 2023 AQUEOUS ALTERNATING ELECTROLYSIS PROLONGS ELECTRODE LIFESPANS UNDER HARSH OPERATION

CONDITIONS Article Open access 23 July 2024 DATA AVAILABILITY The authors declare that the data supporting the findings of this study are available within the paper and its Supplementary

Information. Raw X-ray data generated at the ESRF large-scale facility are available at https://doi.org/10.15151/ESRF-ES-703258873 from 2025. Alternatively, this data can be available from

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Download references ACKNOWLEDGEMENTS The research leading to these results has received funding from the ECOEthylene project from Innovation Fund Denmark (grant no. 8057-00018B), and the

Villum Center for the Science of Sustainable Fuels and Chemicals grant no. 9455. We thank the ESRF for providing the high-energy X-ray beam and ID31 beamline staff for experimental support.

AUTHOR INFORMATION Author notes * These authors contributed equally: Qiucheng Xu, Sahil Garg. AUTHORS AND AFFILIATIONS * Surface Physics and Catalysis (Surf Cat) Section, Department of

Physics, Technical University of Denmark, Lyngby, Denmark Qiucheng Xu, Sahil Garg, Asger B. Moss, Ib Chorkendorff & Brian Seger * Experimental Division, European Synchrotron Radiation

Facility, Grenoble, France Marta Mirolo & Jakub Drnec Authors * Qiucheng Xu View author publications You can also search for this author inPubMed Google Scholar * Sahil Garg View author

publications You can also search for this author inPubMed Google Scholar * Asger B. Moss View author publications You can also search for this author inPubMed Google Scholar * Marta Mirolo

View author publications You can also search for this author inPubMed Google Scholar * Ib Chorkendorff View author publications You can also search for this author inPubMed Google Scholar *

Jakub Drnec View author publications You can also search for this author inPubMed Google Scholar * Brian Seger View author publications You can also search for this author inPubMed Google

Scholar CONTRIBUTIONS Q.X. and S.G. are the lead authors. Q.X. wrote the manuscript with input from all coauthors. S.G. helped revise the manuscript and participated in all results

discussions. Q.X., S.G. and A.B.M. carried out beamline electrochemical measurements and conducted X-ray data analysis. M.M. and J.D. assisted in performing in operando experiments at ESRF.

J.D., I.C. and B.S. guided the project and oversaw its development. B.S. set the overall direction of the project and helped edit the overall manuscript. CORRESPONDING AUTHOR Correspondence

to Brian Seger. ETHICS DECLARATIONS COMPETING INTERESTS The authors declare no competing interests. PEER REVIEW PEER REVIEW INFORMATION _Nature Catalysis_ thanks the anonymous reviewers for

their contribution to the peer review of this work. ADDITIONAL INFORMATION PUBLISHER’S NOTE Springer Nature remains neutral with regard to jurisdictional claims in published maps and

institutional affiliations. SUPPLEMENTARY INFORMATION SUPPLEMENTARY INFORMATION Supplementary Figs. 1–31, Note 1 and Tables 1 and 2. SOURCE DATA SOURCE DATA FIG. 3 Statistical source data.

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alleviating the durability challenges in membrane-electrode-assembly devices for high-rate CO electrolysis. _Nat Catal_ 6, 1042–1051 (2023). https://doi.org/10.1038/s41929-023-01034-y

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