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

Abstract

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 present eCO2RR studies focus on the conversion of pure CO2. The CO2 valorisation chain – from CO2 capture to eCO2RR – requires significant energy and capital inputs in each of the capture, separation, purification, conversion, and product separation step. 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 advance 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, ethanol). We conclude by highlighting major challenges and emerging opportunities in the area of integrated electrochemical CO2 utilisation systems.