Phys.org May 6, 2024
In gas-fed flow electrolyzers equipped with gas diffusion electrodes (GDEs), the reduction of CO2 by Cobalt phthalocyanine (CoPc) selectively produces CO with minimal CH3OH formation. Researchers at the University of Michigan showed that the limited performance of the CO2–CO–CH3OH cascade reactions by CoPc was primarily due to the competitive binding between the CO2 and CO species. They determined that the effective equilibrium constant for CO2 binding was three times higher than that for CO binding. The stronger CO2 binding suppresses the CO-to-CH3OH reaction even at moderate local CO2 concentrations. CH3OH formation was observed when the local concentration of the CO2 was low, compared to the local CO concentration. To promote methanol formation via CO2 reduction, they proposed applying modifications to the coordination environments of CoPc to strengthen the binding of CO and regulate the transport of CO2… read more. TECHNICAL ARTICLE
Graphical abstract. Credit: ACS Catal. 2024, 14, 1, 366–372, December 19, 2023