Cations Make the Difference: Stabilizing Forward-Bias Bipolar Membrane CO 2 Electrolysis
Source abstract
Abstract
Zero-gap CO 2 electrolyzers employing Anion Exchange Membranes (AEMs) ensure beneficial cathodic alkalinity. However, (bi)carbonates formed at the cathode from CO 2 feed gas migrate through the AEM to the anode, releasing gaseous CO 2 . They also react with metal cations translocated from the anolyte, causing malfunction through blocking of the Gas Diffusion Electrode (GDE) by salt precipitation. Forward-bias Bipolar Membranes (BPMs) mitigate anodic CO 2 loss, but cation management remains crucial to avoid salt deposition. In this work, the performance of an electrolysis process employing a forward-bias BPM is optimized and compared to AEM- and reverse-bias BPM-based systems, achieving remarkable Energy Efficiency for CO ( EE CO )≈35%, Faradaic Efficiency for CO ( FE CO ) > 80% and reduced CO 2 loss. An innovative cation management comprising intermittent cation supply to the anolyte is performed, avoiding process failure through salt deposition. Na + -, K + - and Cs + - based electrolytes are investigated, highlighting the influence of metal cation identity on selectivity and stability of the electrolysis process.
Source: crossref · Quality: baseline
Research context
OpenAlex topics: CO2 Reduction Techniques and Catalysts · Electrocatalysts for Energy Conversion · Advanced battery technologies research
SciVX discovery tags are terminology-based. OpenAlex topics are source-provided classifications.
Affiliations
Catalysis Research Center and TUM School of Natural Sciences, Technical University of Munich
Technology Development, Siemens Energy Global GmbH & Co. KG
References (44)
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