Fig. 1: Our new eRCC system for the electrosynthesis of CO₂-inserted cyclic carbonate.

a Schematic of the conventional electrochemical Reactive Carbon Capture (eRCC) and our new eRCC system. In the conventional eRCC system, CO₂ capture by the capturing agent precedes, and electrons are supplied to the captured CO₂ molecule to electrochemically reduce CO₂ and simultaneously regenerate the capturing agent. In contrast, in our new eRCC system initially supplies electrons to the substrate, followed by CO₂ capture by the produced CO₂-capturable substrate. The captured CO₂ then cascades into a CO₂ conversion reaction, resulting in a CO₂-substrate combined product. The colors of the liquids were selected to indicate their basicity: a light yellow color represents a neutral pH, while a pale blue color represents a basic pH. A darker blue color was chosen for halo-alkoxides to indicate that they are more basic than amine species. b Schematic representation of the electrochemical cyclic carbonate synthesis system. Through electrochemical deprotonation, halohydrin becomes capable of capturing CO₂, leading to an intermediate that cascades into a cyclic carbonate. The leaving group detached from the conversion reaction is used at the counter electrode to synthesis halohydrin.