Materials and system design for direct electrochemical CO2 conversion in capture media

Abstract

The electrochemical CO₂ reduction reaction (eCO₂RR) has been regarded as a promising means to store renewable electricity in the form of value-added chemicals or fuels. However, most of the present eCO₂RR studies focus on the conversion of pure CO₂. The CO₂ valorisation chain – from CO₂ capture to the eCO₂RR – requires significant energy and capital inputs in each of the capture, purification, conversion, and product separation steps. The integration of upstream CO₂ capture and downstream electrochemical conversion by direct electrolysis of capture media, such as amine and carbonate salts, offers a potential solution to energy- and cost-efficient utilisation of CO₂. In this perspective, we first summarise the present advances in the direct eCO₂RR from CO₂-capture media. We then focus on potential development directions of materials and systems that boost the process to a phase of high selectivity towards valuable products (e.g., syngas, ethylene, and ethanol). We conclude by highlighting the major challenges and emerging opportunities in the area of integrated electrochemical CO₂ utilisation systems.