CO₂ capture technologies based on chemisorption present the potential to lower net emissions of CO₂ into the atmosphere. The electrochemical upgrade of captured CO₂ to value-added products would be particularly convenient. Here we find that this goal is curtailed when the adduct of the capture molecule with CO₂ fails to place the CO₂ sufficiently close to the site of the heterogeneous reaction. We investigate tailoring the electrochemical double layer to achieve the valorization of chemisorbed CO₂ in an aqueous monoethanolamine electrolyte. We reveal, using electrochemical studies and in situ surface-enhanced Raman spectroscopy, that a smaller double layer distance correlates with improved activity for CO₂ to CO from amine solutions. With the aid of an alkali cation and accelerated mass transport by system design—temperature and concentration—we demonstrate amine–CO₂ conversion to CO with 72% Faradaic efficiency at 50 mA cm^–2.

基于化学吸附的CO ₂捕获技术具有降低进入大气的CO ₂净排放量的潜力。将捕获的CO ₂电化学升级为增值产品将特别方便。在这里，我们发现当捕获分子与CO ₂的加合物未能将CO ₂充分靠近异质反应位点时，这一目标就被削弱了。我们研究定制电化学双层以实现化学吸附的CO ₂的增值在单乙醇胺水溶液中 使用电化学研究和原位表面增强拉曼光谱，我们发现较小的双层距离与胺溶液中CO ₂转化为CO的活性提高有关。借助碱阳离子和通过系统设计（温度和浓度）加速质量传输，我们证明了在50 mA cm ^–2时胺-CO ₂转化为CO的法拉第效率为72％。