Molecular Enhancement of Direct Electrolysis of Dilute CO2

Producing chemicals and fuels via direct electrolysis of dilute CO2 derived from industrial point sources can improve the economic feasibility of CO2 electrolysis technology, yet it suffers from many challenges owing to unfavorable mass transport, reaction thermodynamics, and kinetics. Here we report a molecular enhancement strategy for direct electrolysis of a dilute CO2 stream with a 10% concentration in typical flue gas, using a commercially available cobalt phthalocyanine (CoPc) catalyst. A poly(4-vinylpyridine) (P4VP)-modified CoPc electrode exhibits a remarkable CO partial current density of 252 mA cm–2 with a CO Faradaic efficiency of 90% under the dilute CO2 feed, 2.24-fold higher than that of the bare CoPc electrode. The integration of the CoPc molecule and the P4VP modifier with abundant pyridine moieties creates a reaction microenvironment for sequentially capturing and activating CO2, thus resulting in impressive electrocatalytic performance. The presented molecular enhancement strategy paves the way for direct utilization of a dilute CO2 stream from industrial flue gas.