Electrochemical CO₂ reduction reaction (CO₂RR) offers an appealing route to simultaneously store intermittent renewable energy as value-added chemicals and close carbon cycle. Silver (Ag) catalyst is a promising candidate for the electrochemical conversion of CO₂ to CO, but the electrocatalytic properties are still insufficient for practical applications. Herein, we put forward a strategy to in situ reconstruct a heterogeneous Ag₂S/Ag interface structure, in which their strong interactions facilitate CO₂RR performance. The in situ reconstructive Ag₂S/Ag catalyst achieves a large current density of 421.7 ± 14.4 mA cm^–2 at –0.70 V vs. reversible hydrogen electrode (RHE) and maintains steadily at a current density of 244.5 ± 31.8 mA cm^–2 and CO Faradaic efficiency of 99.1 ± 0.8 % at –0.49 V vs. RHE for 50 h, superior to state-of-the-art CO-selective Ag-based catalysts. Density functional theory calculations reveal that the in situ reconstructive Ag₂S/Ag interface active sites stabilize the *COOH intermediate during CO₂RR process.

电化学CO ₂还原反应（CO ₂ RR）提供了一种吸引人的途径，可以同时存储间歇性可再生能源，作为增值化学品并关闭碳循环。银（Ag）催化剂是将CO ₂电化学转化为CO的有前途的候选物，但电催化性能仍不足以用于实际应用。本文中，我们提出了一种原位重建异质Ag ₂ S / Ag界面结构的策略，其中它们的强相互作用促进了CO ₂ RR性能。在原位重建的Ag ₂ S /银催化剂实现的421.7±14.4毫安厘米的大电流密度^-2在-0.70 V VS。可逆氢电极（RHE），在–0.49 V vs.时稳定地保持在244.5±31.8 mA cm ^–2的电流密度和99.1±0.8％的CO法拉第效率。RHE历时50小时，优于最先进的CO选择性银基催化剂。密度泛函理论计算表明，在CO ₂ RR过程中，原位重建的Ag ₂ S / Ag界面活性位点稳定了* COOH中间体。