CO_(2)-assisted formation of grain boundaries for efficient CO–CO coupling on a derived Cu catalyst

The electrochemical CO_(2)reduction reaction(CO_(2)RR)on Cu catalyst holds great promise for converting CO_(2)into valuable multicarbon(C_(2+))compounds,but still suffers poor selectivity due to the sluggish kinetics of forming carbon–carbon(C–C)bonds.Here we reported a perovskite oxide-derived Cu catalyst with abundant grain boundaries for efficient C–C coupling.These grain boundaries are readily created from the structural reconstruction induced by CO_(2)-assisted La leaching.Using this defective catalyst,we achieved a maximum C_(2+)Faradaic efficiency of 80.3%with partial current density over 400 mA cm−2 in neutral electrolyte in a flow-cell electrolyzer.By combining the structural and spectroscopic investigations,we uncovered that the in-situ generated defective sites trapped by grain boundaries enable favorable CO adsorption and thus promote C–C coupling kinetics for C_(2+)products formation.This work showcases the great potential of perovskite materials for efficient production of valuable multicarbon compounds via CO_(2)RR electrochemistry.

Investigation and Mitigation of Carbon Deposition over Copper Catalyst during Electrochemical CO_(2)Reduction

Copper(Cu)is considered to be the most effective catalyst for electrochemical conversion of carbon dioxide(CO_(2))into value-added hydrocarbons,but its stability still faces considerable challenge.Here,we report the poisoning effect of carbon deposition during CO_(2)reduction on the active sites of Cu electrode
a critical deactivation factor that is often overlooked.We find that,*C,an intermediate toward methane formation,could desorb on the electrode surface to form carbon species.We reveal a strong correlation between the formation of methane and the carbon deposition,and the reaction conditions favoring methane production result in more carbon deposition.The deposited carbon blocks the active sites and consequently causes rapid deterioration of the catalytic performance.We further demonstrate that the carbon deposition can be mitigated by increasing the roughness of the electrode and increasing the pH of the electrolyte.This work offers a new guidance for designing more stable catalysts for CO_(2)reduction.