Although many catalysts have been reported for the CO2 electroreduction to C1 or C2 chemicals,the insuf-ficient understanding of fundamental correlations among different products still hinders the develop-ment of universal catalyst design strategies.Herein,we first discover that the surface *CO coverage is stable over a wide potential range and reveal a linear correlation between the partial current densities of CH4 and C2 products in this potential range,also supported by the theoretical kinetic analysis.Based on the mechanism that *CHO is the common intermediate in the formation of both CH4(*CHO → CH4)and C2(*CHO+*CO → C2),we then unravel that this linear correlation is universal and the slope can be varied by tuning the surface *H or *CO coverage to promote the selectivity of CH4 or C2 products,respectively.As proofs-of-concept,using carbon-coated Cu particles,the surface *H coverage can be increased to enhance CH4 production,presenting a high CO2-to-CH4 Faradaic efficiency(FECH4～52％)and an outstanding CH4 partial current density of-337 mA cm-2.On the other hand,using an Ag-doped Cu catalyst,the CO2RR selectivity is switched to the C2 pathway,with a substantially promoted FEc2 of 79％and a high partial current density of-421 mA cm-2.Our discovery of tuning intermediate coverages suggests a powerful catalyst design strategy for different CO2 electroreduction pathways.

Kunhao Liu;Chao Yang;Ruilin Wei;Xingyu Ma;Chen Peng;Zhengzheng Liu;Yangshen Chen;Yaqin Yan;Miao Kan;Yaoyue Yang;Gengfeng Zheng

Laboratory of Advanced Materials,Department of Chemistry and Shanghai Key Laboratory of Molecular Catalysis and Innovative Materials,Faculty of Chemistry and Materials Science,Fudan University,Shanghai 200438,China;College of Chemistry and Environmental Protection Engineering,Southwest Minzu University,Chengdu 610041,China

科学通报（英文版）

[1]Kunhao Liu;Chao Yang;Ruilin Wei;Xingyu Ma;Chen Peng;Zhengzheng Liu;Yangshen Chen;Yaqin Yan;Miao Kan;Yaoyue Yang;Gengfeng Zheng-.Unraveling and tuning the linear correlation between CH4 and C2 production rates in CO2 electroreduction)[J].科学通报（英文版）,2022(10):1042-1048

CHO+,FECH4,FEc2

Unraveling,tuning,linear,between,C2,production,rates,electroreduction,Although,many,catalysts,have,been,reported,C1,chemicals,insuf,ficient,understanding,fundamental,correlations,among,different,products,still,hinders,develop,universal,design,strategies,Herein,first,that,surface,stable,wide,potential,range,reveal,partial,current,densities,this,also,supported,by,theoretical,kinetic,analysis,Based,mechanism,common,intermediate,formation,both,then,unravel,slope,can,varied,selectivity,respectively,proofs,concept,using,carbon,coated,particles,increased,enhance,presenting,high,Faradaic,efficiency,outstanding,density,mA,On,other,hand,Ag,doped,CO2RR,switched,substantially,promoted,Our,discovery,coverages,suggests,powerful,strategy,pathways

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