Electrocatalytic CO_(2) reduction reaction(ECO_(2)RR)converts CO_(2) to high-value chemical products and promotes the carbon cycle.Sulfur(S)-modified copper(Cu)and bismuth(Bi)-based catalysts have been recognized as p...Electrocatalytic CO_(2) reduction reaction(ECO_(2)RR)converts CO_(2) to high-value chemical products and promotes the carbon cycle.Sulfur(S)-modified copper(Cu)and bismuth(Bi)-based catalysts have been recognized as promising catalysts for ECO_(2)RR.Both of them are highly active for selective formate generation,however,their poor stability and severe competing hydrogen evolution reaction(HER)remain challenging.Herein,S-doped Cu coated with Bi(Bi/Cu-S)is developed to improve ECO_(2)RR selectivity to formate.Bi/Cu-S/brass mesh(BM)electrode material for ECO_(2)RR was prepared by electrodepositing Bi on the surface of Cu-S/BM nanowires obtained from CuS/BM after the electroreduction.The Faradaic efficiency(FE)of the formate reaches the maximum of 94.3%at-0.9 V vs.reversible hydrogen electrode(RHE)with a partial current density as high as-50.7 mA·cm^(-2) and a yield of 30.7 mmol·h^(-1)·cm^(-2) under 0.5 M KHCO_(3) electrolyte.Meanwhile,the FE of formate is higher than 90%in the voltage range of-0.8 to-1.0 V vs.RHE.It also shows good stability at-0.9 V vs.RHE with the FE of formate remaining above 93%after a 10 h reaction.Density functional theory(DFT)calculations demonstrate that the Bi/Cu-S structure promotes the adsorption of CO_(2) and effectively inhibits HER by enhancing the adsorption of^(*)H to a great extent,improving the selective conversion of CO_(2) to formate.This work deepens the understanding of the mechanism of Cu-Bi-based catalysts and S-modified Cu-based catalysts in selective ECO_(2)RR to formate,and also provides a new strategy for catalyst design.展开更多
基金supported by the National Natural Science Foundation of China(Nos.22278020,2177060378)the Program for Changjiang Scholars,Innovative Research Teams in Universities(No.IRT1205)the Fundamental Research Funds for the Central Universities(Nos.12060093063,XK1803-05).
文摘Electrocatalytic CO_(2) reduction reaction(ECO_(2)RR)converts CO_(2) to high-value chemical products and promotes the carbon cycle.Sulfur(S)-modified copper(Cu)and bismuth(Bi)-based catalysts have been recognized as promising catalysts for ECO_(2)RR.Both of them are highly active for selective formate generation,however,their poor stability and severe competing hydrogen evolution reaction(HER)remain challenging.Herein,S-doped Cu coated with Bi(Bi/Cu-S)is developed to improve ECO_(2)RR selectivity to formate.Bi/Cu-S/brass mesh(BM)electrode material for ECO_(2)RR was prepared by electrodepositing Bi on the surface of Cu-S/BM nanowires obtained from CuS/BM after the electroreduction.The Faradaic efficiency(FE)of the formate reaches the maximum of 94.3%at-0.9 V vs.reversible hydrogen electrode(RHE)with a partial current density as high as-50.7 mA·cm^(-2) and a yield of 30.7 mmol·h^(-1)·cm^(-2) under 0.5 M KHCO_(3) electrolyte.Meanwhile,the FE of formate is higher than 90%in the voltage range of-0.8 to-1.0 V vs.RHE.It also shows good stability at-0.9 V vs.RHE with the FE of formate remaining above 93%after a 10 h reaction.Density functional theory(DFT)calculations demonstrate that the Bi/Cu-S structure promotes the adsorption of CO_(2) and effectively inhibits HER by enhancing the adsorption of^(*)H to a great extent,improving the selective conversion of CO_(2) to formate.This work deepens the understanding of the mechanism of Cu-Bi-based catalysts and S-modified Cu-based catalysts in selective ECO_(2)RR to formate,and also provides a new strategy for catalyst design.
