Electrochemical CO₂ reduction is a promising approach for upgrading excessive CO₂ into value-added chemicals, while the exquisite control of the catalyst atomic structures to obtain high C₂₊ alcohol selectivity has remained challenging due to the intrinsically favored ethylene pathways at Cu surface. Herein, we demonstrate a rational strategy to achieve ∼70% faradaic efficiency toward C₂₊ alcohols. We utilized a CO-rich environment to construct Cu catalysts with stepped sites that enabled high surface coverages of ∗CO intermediates and the bridge-bound ∗CO adsorption, which allowed to trigger CO₂ reduction pathways toward the formation alcohols. Using this defect-site-rich Cu catalyst, we achieved C₂₊ alcohols with partial current densities of > 100 mA·cm⁻² in both a flow-cell electrolyzer and a membrane electrode assembly (MEA) electrolyzer. A stable alcohol faradaic efficiency of ∼60% was also obtained, with ∼500 mg C₂₊ alcohol production per cm² catalyst during a continuous 30-h operation.

电化学还原CO ₂是将过量的CO ₂升级为增值化学品的一种有前途的方法，而由于铜表面固有的乙烯途径，如何精确控制催化剂原子结构以获得高的C ₂₊醇选择性仍然具有挑战性。本文中，我们展示了一种合理的策略，可实现对C ₂₊醇约70％的法拉第效率。我们利用富含CO的环境构建具有阶梯状位点的Cu催化剂，从而使＊ CO中间体具有很高的表面覆盖率，并通过桥式结合的＊ CO吸附，从而触发了朝向形成醇的CO ₂还原途径。使用这种富含缺陷部位的Cu催化剂，我们获得了C在流通池电解槽和膜电极组件（MEA）电解槽中，部分电流密度大于100 mA·cm ^-2的_2+种醇。在连续30小时的操作过程中，每cm ²催化剂产生约500 mg C ₂₊醇，还获得了约60％的稳定醇法拉第效率。