Electrochemical carbon dioxide reduction (CO₂) is a promising technology to use renewable electricity to convert CO₂ into valuable carbon‐based products. For commercial‐scale applications, however, the productivity and selectivity toward multi‐carbon products must be enhanced. A facile surface reconstruction approach that enables tuning of CO₂‐reduction selectivity toward C₂₊ products on a copper‐chloride (CuCl)‐derived catalyst is reported here. Using a novel wet‐oxidation process, both the oxidation state and morphology of Cu surface are controlled, providing uniformity of the electrode morphology and abundant surface active sites. The Cu surface is partially oxidized to form an initial Cu (I) chloride layer which is subsequently converted to a Cu (I) oxide surface. High C₂₊ selectivity on these catalysts are demonstrated in an H‐cell configuration, in which 73% Faradaic efficiency (FE) for C₂₊ products is reached with 56% FE for ethylene (C₂H₄) and overall current density of 17 mA cm^‐2. Thereafter, the method into a flow‐cell configuration is translated, which allows operation in a highly alkaline medium for complete suppression of CH₄ production. A record C₂₊ FE of ≈84% and a half‐cell power conversion efficiency of 50% at a partial current density of 336 mA cm^‐2 using the reconstructed Cu catalyst are reported.

中文翻译：

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CO2电解还原成C2 +碳氢化合物的高生产率和选择性的表面重建途径

电化学减少二氧化碳（CO ₂）是一种有前途的技术，可利用可再生电力将CO ₂转化为有价值的碳基产品。但是，对于商业规模的应用，必须提高对多碳产品的生产率和选择性。一种简便的表面重建方法，可以调节CO ₂还原对C _2+的选择性此处报道了使用氯化铜（CuCl）衍生的催化剂生产的产品。使用新颖的湿式氧化工艺，可控制铜表面的氧化态和形态，从而提供均匀的电极形态和丰富的表面活性位。Cu表面被部分氧化以形成初始的氯化铜（I）层，随后将其转化为氧化铜（I）表面。这些催化剂在H电池构型中具有很高的C ₂₊选择性，其中C ₂₊产物的法拉第效率（FE）达到73％，乙烯（C ₂ H ₄）的FE达到56％，总电流密度17 mA厘米^‐2。此后，将该方法转换为流通池配置，从而可以在高碱性介质中运行，从而完全抑制CH _4的产生。据报道，使用重构的Cu催化剂，在336 mA cm ^-2的部分电流密度下，C ₂₊ FE达到了约84％的创纪录水平，半电池功率转换效率为50％。