Investigating Electrode Flooding in a Flowing Electrolyte, Gas‐Fed Carbon Dioxide Electrolyzer
Name
Investigating_Electrode_Flooding_in_a_Flowing_Electrolyte__Gas-Fed_Carbon_Dioxide_Electrolyzer_v2.pdf
Description
Accepted version
Size
3.86 MB
Format
Adobe PDF
Checksum (MD5)
2e801159531163e22a26629085b5feb6
Author(s)
Leonard, McLain E
Clarke, Lauren E
Forner‐Cuenca, Antoni
Brown, Steven M
Brushett, Fikile R
Date Issued
2020
Journal
ChemSusChem
Publisher
Wiley
Version
Author's final manuscript
Abstract
© 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim Managing the gas–liquid interface within gas-diffusion electrodes (GDEs) is key to maintaining high product selectivities in carbon dioxide electroreduction. By screening silver-catalyzed GDEs over a range of applied current densities, an inverse correlation was observed between carbon monoxide selectivity and the electrochemical double-layer capacitance, a proxy for wetted electrode area. Plotting current-dependent performance as a function of cumulative charge led to data collapse onto a single sigmoidal curve indicating that the passage of faradaic current accelerates flooding. It was hypothesized that high cathode alkalinity, driven by both initial electrolyte conditions and cathode half-reactions, promotes carbonate formation and precipitation which, in turn, facilitates electrolyte permeation. This mechanism was reinforced by the observations that post-test GDEs retain less hydrophobicity than pristine materials and that water-rinsing and drying electrodes temporarily recovers peak selectivity. This knowledge offers an opportunity to design electrodes with greater carbonation tolerance to improve device longevity.
MIT Department
Massachusetts Institute of Technology. Department of Chemical Engineering
Terms of Use
Creative Commons Attribution-Noncommercial-Share Alike
Persistent DSpace Link
DOI of Published Version
https://doi.org/10.1002/CSSC.201902547
