Toward Complete CO <sub>2</sub> Electroconversion: Status, Challenges, and Perspectives
Changfan Xu, Ping Hong, Yulian Dong, Marc Robert, Guosheng Shao, Yong Lei
Abstract
Abstract Electrocatalytic conversion of carbon dioxide (CO 2 ) into valuable carbon‐based fuels and chemicals represents a promising approach to closing the carbon cycle and setting a circular economy. Nevertheless, for current electrocatalytic CO 2 reduction reaction (ECO 2 RR) systems, realizing 100% CO 2 conversion with simultaneously high overall CO 2 conversion rate (i.e., single‐pass conversion) and high Faradaic efficiency (FE) remains a significant challenge. Enhancing CO 2 conversion rate often results in a decrease in FE, conversely, improving FE may limit the CO 2 conversion rate. Metal–CO 2 (M–CO 2 ) batteries with CO 2 conversion functions face similar challenges, particularly for reversible M–CO 2 batteries, which do not accomplish net CO 2 reduction because nearly all of CO 2 RR products are reoxidized to CO 2 during subsequent charging process. Such electrocatalytic CO 2 conversion system for carbon neutrality poses substantial challenges. This perspective provides an in‐depth analysis of state‐of‐the‐art ECO 2 RR systems and M–CO 2 batteries, alongside the main strategies employed to address their respective challenges. The critical importance of achieving both a high CO 2 conversion rate and high Faradaic efficiency is underscored for practical applications and to effectively close the carbon cycle. Furthermore, a strategic roadmap that outlines future research directions is presented, thereby facilitating the advancement of comprehensive CO 2 electroconversion technologies.