Electrochemical reduction of carbon dioxide(CO_(2)RR)is a promising approach to complete the carbon cycle and potentially convert CO_(2)into valuable chemicals and fuels.Cu is unique among transition metals in its abi...Electrochemical reduction of carbon dioxide(CO_(2)RR)is a promising approach to complete the carbon cycle and potentially convert CO_(2)into valuable chemicals and fuels.Cu is unique among transition metals in its ability to catalyze the CO_(2)RR and produce multi-carbon products.However,achieving high selectivity for C2+products is challenging for copper-based catalysts,as C–C coupling reactions proceed slowly.Herein,a surface modification strategy involving grafting long alkyl chains onto copper nanowires(Cu NWs)has been proposed to regulate the electronic structure of Cu surface,which facilitates*CO-*CO coupling in the CO_(2)RR.The hydrophobicity of the catalysts increases greatly after the introduction of long alkyl chains,therefore the hydrogen evolution reaction(HER)has been inhibited effectively.Such surface modification approach proves to be highly efficient and universal,with the Faradaic efficiency(FE)of C_(2)H_(4) up to 53%for the optimized Cu–SH catalyst,representing a significant enhancement compared to the pristine Cu NWs(30%).In-situ characterizations and theoretical calculations demonstrate that the different terminal groups of the grafted octadecyl chains can effectively regulate the charge density of Cu NWs interface and change the adsorption configuration of*CO intermediate.The top-adsorbed*CO intermediates(*COtop)on Cu–SH catalytic interface endow Cu–SH with the highest charge density,which effectively lowers the reaction energy barrier for*CO-*CO coupling,promoting the formation of the*OCCO intermediate,thereby enhancing the selectivity towards C_(2)H_(4).This study provides a promising method for designing efficient Cu-based catalysts with high catalytic activity and selectivity towards C2H4.展开更多
文摘Electrochemical reduction of carbon dioxide(CO_(2)RR)is a promising approach to complete the carbon cycle and potentially convert CO_(2)into valuable chemicals and fuels.Cu is unique among transition metals in its ability to catalyze the CO_(2)RR and produce multi-carbon products.However,achieving high selectivity for C2+products is challenging for copper-based catalysts,as C–C coupling reactions proceed slowly.Herein,a surface modification strategy involving grafting long alkyl chains onto copper nanowires(Cu NWs)has been proposed to regulate the electronic structure of Cu surface,which facilitates*CO-*CO coupling in the CO_(2)RR.The hydrophobicity of the catalysts increases greatly after the introduction of long alkyl chains,therefore the hydrogen evolution reaction(HER)has been inhibited effectively.Such surface modification approach proves to be highly efficient and universal,with the Faradaic efficiency(FE)of C_(2)H_(4) up to 53%for the optimized Cu–SH catalyst,representing a significant enhancement compared to the pristine Cu NWs(30%).In-situ characterizations and theoretical calculations demonstrate that the different terminal groups of the grafted octadecyl chains can effectively regulate the charge density of Cu NWs interface and change the adsorption configuration of*CO intermediate.The top-adsorbed*CO intermediates(*COtop)on Cu–SH catalytic interface endow Cu–SH with the highest charge density,which effectively lowers the reaction energy barrier for*CO-*CO coupling,promoting the formation of the*OCCO intermediate,thereby enhancing the selectivity towards C_(2)H_(4).This study provides a promising method for designing efficient Cu-based catalysts with high catalytic activity and selectivity towards C2H4.
