Catalyzed Porous Electrodes for CO2 Conversion to Multicarbon Organics at High Single Product Selectivity and Low Over-Potential

The conversion of carbon dioxide (CO2) to value-added multi-carbon (with two or more than two C-C bonds) organic compounds by electrocatalytic reduction of CO2 provides a promising and value-added route to mitigate the greenhouse gas emission. Here, I present a family of porous carbon electrodes embbeded with transition and non-transition metals with varying sizes ranging from single atoms to few atom clusters. These porous carbon electrodes electrocatalytically reduce CO2 to C2 and C3 liquid organic compounds with high single-product selectivity at relatively low potentials. The reaction mechanism is extensively studied by Operando synchrotron X-ray absorption techniques and kinetic isotope effect to identify the dynamic evolution of the catalytic center. It is stunning to reveal that atomically dispersed catalytic metal atoms aggregate to few-atom clusters under reductive potentials and depending on the redox potentials of the metals, oxygen atoms can also involve in the catalytic center. In addition, the supporting substrates exhibit a profound nano confinement effect that also impacts the reaction pathways towards C-C coupling. Our work renders atomistic and quantum mechanical level understanding in the reaction coordination for electrochemical CO2 reduction reaction to a versatility of value-added organic compounds.