oCEMBER2mc · Operando-guided bicarbonate electroreduction to multicarbon products in cation exchange membrane electrolyzers

In response to the EU Green Deal’s goal of achieving climate neutrality by 2050, efficient carbon capture and utilization (CCU) technologies are urgently needed to close the carbon cycle. Direct bicarbonate electroreduction (BER) is a promising approach because it can circumvent the energy-intensive, thermal CO2 regeneration step in conventional CO2 electroreduction combined with alkaline liquid-based carbon capture technology. Copper electrode materials can drive the direct conversion of the liquid captured carbon towards valuable multicarbon products, yet the process still suffers from limited activity and selectivity. In addition, current BER electrolyzer designs require high cell voltages, largely because of the immature bipolar membrane technology which causes significant energy losses through water dissociation. As a result, achieving energy-efficient conversion of bicarbonate into multicarbon products remains a critical unsolved challenge.This project introduces a new electrolyzer configuration based on the established cation exchange membrane (CEM) technology combined with surface-modified oxide-derived copper electrodes to enable efficient bicarbonate-to-multicarbon conversion. Operando Raman and in situ synchrotron X-ray spectroscopy will directly track interfacial properties suitable as activity and selectivity descriptors, including local pH, adsorbed surface species, and Cu oxidation states under industrially relevant conditions. These insights will guide a multi-scale optimization strategy across catalyst chemistry, electrolyte composition, and membrane–electrode microenvironment, establishing a mechanism-driven framework with transferable principles for advancing bicarbonate electrolysis. By overcoming the combined challenges of low reactivity and high energy demand, the project will provide a viable pathway for direct CO2 utilization, contribute to Europe’s leadership in sustainable catalysis, and directly support the EU’s net-zero agenda.