Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products
© 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. Economic operation of carbon dioxide (CO2) electrolyzers generating liquid products will likely require high reactant conversions and product concentrations, conditions anticipated to challenge existi...
| Main Authors: | , , , , , |
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| Format: | Article |
| Language: | English |
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The Electrochemical Society
2021
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| Online Access: | https://hdl.handle.net/1721.1/135374 |
| _version_ | 1811093864764669952 |
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| author | Leonard, McLain E Orella, Michael J Aiello, Nicholas Román-Leshkov, Yuriy Forner-Cuenca, Antoni Brushett, Fikile R |
| author_facet | Leonard, McLain E Orella, Michael J Aiello, Nicholas Román-Leshkov, Yuriy Forner-Cuenca, Antoni Brushett, Fikile R |
| author_sort | Leonard, McLain E |
| collection | MIT |
| description | © 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. Economic operation of carbon dioxide (CO2) electrolyzers generating liquid products will likely require high reactant conversions and product concentrations, conditions anticipated to challenge existing gas diffusion electrodes (GDEs). Notably, electrode wettability will increase as lower surface tension products (e.g., formic acid, alcohols) are introduced into electrolyte streams, potentially leading to flooding. To understand the hydraulically stable operating envelopes in mixed aqueous-organic liquid domains, we connect intrinsic electrode wettability descriptors to operating parameters such as electrolyte flow rate and current. We first measure contact angles of water-organic product dilutions on polytetrafluoroethylene (PTFE) and graphite surfaces as planar analogues for GDE components. We then use material balances around the reactive gas-liquid-solid interface to calculate product mass fractions as functions of water sweep rate and current. Product composition maps visualize the extent to which changes in cell performance influence capillary pressure, a determinant of GDE saturation. Analyses suggest that formic acid mixtures pose little risk for GDE flooding across a wide range of conditions, but effluents containing <30% alcohol by mass may cause flooding. This study reveals opportunities to integrate microstructural features and oleophobic surface treatments into GDEs to repel aqueous-organic mixtures and expand the window of stable operating conditions. |
| first_indexed | 2024-09-23T15:51:55Z |
| format | Article |
| id | mit-1721.1/135374 |
| institution | Massachusetts Institute of Technology |
| language | English |
| last_indexed | 2024-09-23T15:51:55Z |
| publishDate | 2021 |
| publisher | The Electrochemical Society |
| record_format | dspace |
| spelling | mit-1721.1/1353742021-10-28T03:17:34Z Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products Leonard, McLain E Orella, Michael J Aiello, Nicholas Román-Leshkov, Yuriy Forner-Cuenca, Antoni Brushett, Fikile R © 2020 The Author(s). Published on behalf of The Electrochemical Society by IOP Publishing Limited. Economic operation of carbon dioxide (CO2) electrolyzers generating liquid products will likely require high reactant conversions and product concentrations, conditions anticipated to challenge existing gas diffusion electrodes (GDEs). Notably, electrode wettability will increase as lower surface tension products (e.g., formic acid, alcohols) are introduced into electrolyte streams, potentially leading to flooding. To understand the hydraulically stable operating envelopes in mixed aqueous-organic liquid domains, we connect intrinsic electrode wettability descriptors to operating parameters such as electrolyte flow rate and current. We first measure contact angles of water-organic product dilutions on polytetrafluoroethylene (PTFE) and graphite surfaces as planar analogues for GDE components. We then use material balances around the reactive gas-liquid-solid interface to calculate product mass fractions as functions of water sweep rate and current. Product composition maps visualize the extent to which changes in cell performance influence capillary pressure, a determinant of GDE saturation. Analyses suggest that formic acid mixtures pose little risk for GDE flooding across a wide range of conditions, but effluents containing <30% alcohol by mass may cause flooding. This study reveals opportunities to integrate microstructural features and oleophobic surface treatments into GDEs to repel aqueous-organic mixtures and expand the window of stable operating conditions. 2021-10-27T20:23:11Z 2021-10-27T20:23:11Z 2020 2021-06-09T15:22:08Z Article http://purl.org/eprint/type/JournalArticle https://hdl.handle.net/1721.1/135374 en 10.1149/1945-7111/ABAA1A Journal of the Electrochemical Society Creative Commons Attribution 4.0 International license https://creativecommons.org/licenses/by/4.0/ application/pdf The Electrochemical Society IOP Publishing |
| spellingShingle | Leonard, McLain E Orella, Michael J Aiello, Nicholas Román-Leshkov, Yuriy Forner-Cuenca, Antoni Brushett, Fikile R Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products |
| title | Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products |
| title_full | Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products |
| title_fullStr | Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products |
| title_full_unstemmed | Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products |
| title_short | Editors’ Choice—Flooded by Success: On the Role of Electrode Wettability in CO 2 Electrolyzers that Generate Liquid Products |
| title_sort | editors choice flooded by success on the role of electrode wettability in co 2 electrolyzers that generate liquid products |
| url | https://hdl.handle.net/1721.1/135374 |
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