The reduction of carbon dioxide to renewable fuels and feedstocks offers opportunities for large-scale, long-term energy storage. The synthesis of efficient CO₂ reduction electrocatalysts with high C2:C1 selectivity remains a field of intense interest. Here we present electro-redeposition, the dissolution and redeposition of copper from a sol–gel, to enhance copper catalysts in terms of their morphology, oxidation state and consequent performance. We utilized in situ soft X-ray absorption spectroscopy to track the oxidation state of copper under CO₂ reduction conditions with time resolution. The sol–gel material slows the electrochemical reduction of copper, enabling control over nanoscale morphology and the stabilization of Cu⁺ at negative potentials. CO₂ reduction experiments, in situ X-ray spectroscopy and density functional theory simulations revealed the beneficial interplay between sharp morphologies and Cu⁺ oxidation state. The catalyst exhibits a partial ethylene current density of 160 mA cm^–2 (−1.0 V versus reversible hydrogen electrode) and an ethylene/methane ratio of 200.

将二氧化碳减少为可再生燃料和原料提供了大规模，长期能源存储的机会。具有高C 2：C 1选择性的有效的CO ₂还原电催化剂的合成仍然是令人关注的领域。在这里，我们介绍电沉积，从溶胶-凝胶中溶解和再沉积铜的方法，以增强铜催化剂的形态，氧化态和相应的性能。我们利用原位软X射线吸收光谱法以时间分辨率跟踪在CO ₂还原条件下铜的氧化态。溶胶-凝胶材料减慢了铜的电化学还原速度，可以控制纳米尺度的形貌，并在负电势下稳定Cu ⁺。一氧化碳_2个还原实验，原位X射线光谱学和密度泛函理论模拟揭示了尖锐形貌与Cu ⁺氧化态之间的有益相互作用。该催化剂的部分乙烯电流密度为160 mA cm ^-2（相对于可逆氢电极为-1.0 V），乙烯/甲烷比为200。