(47b) Integrating Nonaqueous CO2 Capture and Electrochemical Conversion

Integrating reactive CO₂ capture and electrochemical conversion offers a promising pathway toward achieving net zero greenhouse gas emissions. However, the effectiveness of amine-CO2 electrochemical reduction in aqueous environments is hindered by the competing hydrogen evolution reaction (HER), primarily due to the abundance of proton sources. Additionally, the generation of carbon-containing products has typically been limited to scenarios involving noble metal catalysts and high CO₂ partial pressures.

In this study, we address these challenges by implementing CO₂ capture and conversion within a nonaqueous medium. Spectroscopic analysis reveals a nearly threefold increase in carbon load compared to aqueous environments. By strategically limiting proton source availability, we achieve an impressive 80% faradaic efficiency (FE) towards CO production using an earth-abundant catalyst. Our techno-economic analysis demonstrates that this enhanced electrochemical performance offsets the higher electrolyte costs associated with nonaqueous media compared to water.

Furthermore, we extend our approach to the reduction of CO₂ found in industrially relevant gas compositions, achieving a notable 40% FE for CO production. Our findings not only contribute valuable insights into electrolyte design for integrated CO₂ capture and conversion but also hold significant implications for addressing CO₂ emissions from industrial sources.