Electrochemical reduction of CO₂ to value-added multicarbon products has been limited by the inefficiency of the C–C coupling process on Cu. Coupling metal oxides with Cu surfaces offers new freedom to break scaling relationships, thus regulating the product distribution on Cu. Herein, we show that metal oxides with the capability to stabilize the adsorbed CO₂∗/CO∗ and decrease the Gibbs free energies of the C–C coupling process can promote the formation of C₂₊ products on oxide-modified Cu electrodes. As a representative, ZrO₂-modified Cu (Cu/ZrO₂) electrode shows a high faradic efficiency of 85% for C₂₊ products. In situ surface-enhanced Raman spectra confirm the enhanced adsorption of CO∗ on the Cu/ZrO₂ electrode, while theoretical calculations reveal the decreased energy barriers of the C–C coupling process at the Cu-ZrO₂ interfacial boundaries. This study sheds light on the structure-property relationship of metal-oxide heterostructured electrocatalysts and accelerates the implementation of CO₂ electroreduction toward high-value products.

_{将 CO 2}电化学还原为高附加值的多碳产品受到了 Cu 上 C-C 偶联过程的低效率的限制。将金属氧化物与铜表面偶联提供了打破结垢关系的新自由度，从而调节了铜上的产物分布。在此，我们表明金属氧化物能够稳定吸附的 CO ₂ */CO * 并降低 C-C 耦合过程的吉布斯自由能，可以促进氧化物修饰的 Cu 电极上C _{2+产物的形成。}作为代表，ZrO ₂修饰的Cu（Cu/ZrO _{2 ）电极对C 2+}产品表现出85%的高法拉第效率。原位表面增强拉曼光谱证实了 CO* 在 Cu/ZrO ₂电极上的吸附增强，而理论计算表明在 Cu-ZrO ₂界面边界处 C-C 耦合过程的能垒降低。该研究阐明了金属氧化物异质结构电催化剂的结构-性能关系，并加速了CO ₂电还原向高价值产品的实施。