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工业规模的化石能源消耗导致大气中二氧化碳含量不断增加,CO2转化利用成为人们日益关注的热点问题.金属铜因其成本低廉、储量丰富,并且具有独特的CO2亲和力能够生成多碳化合物,是目前CO2电还原中研究最为广泛深入的电极材料.由于阴、阳离子的特征吸附对Cu电极性能有显著影响,并且不同反应体系中对Cu电极上CO2吸附、活化影响也有所不同,因此导致金属Cu电极上报道的电催化活性、产物种类与选择性等都非常宽泛.基于此,有必要系统地研究各种反应条件对金属Cu电极电催化CO2还原性能的影响.作者选择了平均粒径为600nm的商品化金属Cu颗粒作为电还原CO2的催化剂,研究了不同反应条件包括各种常用电解质溶液、KHCO3的浓度以及H型电解池和流动池.实验结果表明,浓度为0.5 molL-1的KHCO3作为电解质溶液具有较好催化活性和较高的产物分电流密度,流动池可以进一步提高主要产物甲酸盐和CO的分电流密度.本研究工作从反应条件的角度对CO2还原的电催化转化进行了系统研究,有助于理解电解液和反应器等因素对CO2电还原反应过程的影响规律.“,”Electrochemical conversion of carbon dioxide(CO2)driven by renewable electricity that can meet both carbon emis-sion reduction and renewable energy utilization has been rapidly developed in recent years.Copper(Cu)catalyst has long been a promising candidate for CO2 electroreduction applications because of its natural abundance and specific capability of producing a substantial amount of C2 products.However,various metallic Cu electrodes reported have been significantly influenced by the ad-sorption of certain cation/anion ions,resulting in wide-span catalytic activities and selectivity for various products.In addition,a re-cent report demonstrated that by virtue of gas-diffusion flow cell with Cu cathode,remarkable ethylene production was achieved in CO2 electroreduction.It is,therefore,desirable to systematically investigate the effect of reaction conditions on the performances of Cu-catalyzed CO2 electroreduction.Here we chose the commercial Cu particles with an average size of 600 nm as the catalyst for CO2 electroreduction and investigated the electrocatalytic performances under various reaction conditions,including the commonly used electrolyte solutions,the different potassium hydrogen carbonate(KHCO3)concentrations,as well as H-type and gas-diffusion flow cells.The results of linear sweep voltammetry and potentiostatic CO2 electrolysis showed that KHCO3 as an electrolyte solu-tion with a concentration of 0.5 mol·L-1 offered good catalytic activities and high current densities,and the gas-diffusion flow cell could further improve the Faradaic efficiencies and partial current densities of the main products formate and CO.This work pro-vides a fundamental insight to the electrocatalytic conversion of CO2 reduction from the view of reaction conditions.