Electrolyte Solution for Reversible CO2 Capture and Electrochemical Conversion

Abstract

The electrochemical reduction of CO2 in nonaqueous systems presents a promising avenue for carbon capture and utilization. The role of Fe-based anionic species (FeCl4− and Fe2Cl7−) in mediating CO2 activation and conversion within a quaternary amine-based eutectic electrolyte is accomplished using FTIR spectroscopy and electrochemical techniques, while confirming the formation of Fe—CO2 adducts upon CO2 purging. The electrolyte offers high carbon capture efficiency (14.3 g/L) with a diffusion coefficient of ~1×10−7 cm2/s. The CO2 integrated electrochemical cell delivers a high discharge capacity of 0.3 mAh/cm2 and cycling efficiency reaching >20 cycles. During electrochemical discharge, the Fe—CO2 adducts undergo electron-driven transformations, producing CO2 reduction products such as formate, and carbonate. The triethylammonium cation in the electrolyte forms a neutral triethylamine, releasing CO2 radicals.

Dependencies are inferred from the claim text.