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To valorize waste CO2, capturing and utilizing it to produce chemical building blocks is currently receiving a lot of attention. In this respect, amine and alkali base solutions have shown to be efficient CO2 capturing solutions and electrochemical CO2 conversion is a promising technology to convert CO2 and, as such, reduce greenhouse gas emissions. However, to date, CO2 capture and utilization (CCU) technologies have been investigated almost exclusively as separate processes. This has the disadvantage that CO2 has to be desorbed and compressed from the capture solution before sending it to the CO2 electrolyzer, seriously increasing the capital and operational costs of the overall technology. To improve the valorization potential of the CCU technologies, integrating both technologies by directly utilizing the capture solution as an electrolyte for the electrochemical CO2 reduction (eCO2R) is a highly promising approach. This technology is however limited by low Faradaic efficiencies (FE) and partial current densities that can be achieved with these solutions. The main reason for this is the slow CO2 release rate at the catalytic interphase. Nevertheless, in recent years, in light of tackling these challenges, several studies successfully managed to decrease the costs of the CO2 capturing step and to electrochemically convert more efficiently the CO2 capture solutions. Herein, we review the status of the integrated CO2 capture and electrochemical conversion technology, discussing the recent developments and advances both in the field of CO2 capture and eCO2R.

Integrating alkaline capture of CO 2 from air with electrochemical conversion of the obtained (bi)carbonate solution is among the most promising strategies in carbon capture and utilization (CCU) technologies. Thus far, this approach has received little or no attention because of the challenging conversions of CO 2 from bicarbonate solutions because of the parasitic hydrogen evolution reaction (HER). Very recently, thanks to the advances in reactor design and the understanding of the mechanism of bicarbonate electrolysis, promising results were obtained in terms of performance (i.e., >60% FE toward formate or CO at >50 mA cm −2 ) and as such provided us with the required know-how to, for the first time, construct and validate a proof-of-concept experimental setup where CO 2 is captured from air, in the form of a (bi)carbonate solution, through direct air capture and then converted to formate and CO in a zero-gap flow electrolyzer. The presented results provide a new opportunity for upscaling the electrochemical conversion of CO 2 , since integrating the capture and the conversion steps is a crucial step to enhance the economic feasibility of the CCU technology (energy-intensive CO 2 separation can be avoided) and thus increase its chances of industrial implementation.