Oxide-derived copper (OD-Cu) materials exhibit extraordinary catalytic activities in the electrochemical carbon dioxide reduction reaction (CO₂RR), which likely relates to non-metallic material constituents formed in transitions between the oxidized and the reduced material. In time-resolved operando experiment, we track the structural dynamics of copper oxide reduction and its re-formation separately in the bulk of the catalyst material and at its surface using X-ray absorption spectroscopy and surface-enhanced Raman spectroscopy. Surface-species transformations progress within seconds whereas the subsurface (bulk) processes unfold within minutes. Evidence is presented that electroreduction of OD-Cu foams results in kinetic trapping of subsurface (bulk) oxide species, especially for cycling between strongly oxidizing and reducing potentials. Specific reduction-oxidation protocols may optimize formation of bulk-oxide species and thereby catalytic properties. Together with the Raman-detected surface-adsorbed *OH and C-containing species, the oxide species could collectively facilitate *CO adsorption, resulting an enhanced selectivity towards valuable C₂₊ products during CO₂RR.

氧化物衍生的铜（OD-Cu）材料在电化学二氧化碳还原反应（CO ₂ RR）中表现出非凡的催化活性，这可能与氧化材料和还原材料之间的转变中形成的非金属材料成分有关。在时间分辨原位实验中，我们使用 X 射线吸收光谱和表面增强拉曼光谱分别跟踪催化剂材料本体和表面氧化铜还原及其重新形成的结构动力学。表面物种转变在几秒钟内完成，而地下（整体）过程在几分钟内展开。有证据表明，OD-Cu 泡沫的电还原会导致地下（块状）氧化物物质的动力学捕获，尤其是在强氧化电位和还原电位之间的循环时。特定的还原-氧化方案可以优化本体氧化物物质的形成，从而优化催化性能。与拉曼检测到的表面吸附的 *OH 和含 C 物质一起，氧化物物质可以共同促进 *CO 吸附，从而在 CO _{2 RR 过程中提高对有价值的 C 2+}产物的选择性。