The electrocatalytic CO₂ reduction (converting redundant CO₂ into carbon-neutral fuels) holds a great potential to battle the energy and environmental crisis. The Ag-based materials stand out from the pool of catalysts because of its high Faradic efficiencies for CO formation. In this work, thin Ag polycrystalline film was synthesized on carbon papers by a simple vacuum evaporation method. After 15 minutes of O₃ treatment under ambient temperature, the Ag electrocatalysts can produce CO with a Faradic efficiency of up to 93.3 % at −0.9 V versus reversible hydrogen electrode (vs. RHE), which is higher than that of pristine Ag. In addition, the Ag electrode retained ∼90 % catalytic selectivity for CO after a 10-hour test. The characterizations show that the surface Ag_xO layer on Ag was reduced to Ag⁰, which not only reduces the activation energy barrier of the initial electron transfer but also provides an increased number of active sites for the reduction of CO₂ to CO.

中文翻译：

---

表面氧化银纳米膜实现高效二氧化碳减排

电催化 CO ₂还原（将多余的 CO ₂转化为碳中性燃料）在应对能源和环境危机方面具有巨大潜力。银基材料因其形成 CO 的高法拉第效率而从催化剂池中脱颖而出。在这项工作中，通过简单的真空蒸发方法在复写纸上合成了薄的 Ag 多晶薄膜。O ₃ 15 分钟后在环境温度下处理后，Ag 电催化剂可以在 -0.9 V 下产生 CO，法拉第效率高达 93.3%，而可逆氢电极（vs. RHE）高于原始 Ag 的法拉第效率。此外，在 10 小时的测试后，Ag 电极对 CO 保持约 90% 的催化选择性。表征表明，Ag 上的表面 Ag _x O 层被还原为 Ag ⁰，这不仅降低了初始电子转移的活化能势垒，而且为将 CO ₂还原为 CO 提供了更多的活性位点。