Developing highly selective and active electrocatalysts for the NO₃⁻ reduction reaction (NO₃RR) has attracted significant interest. Here, we improved the catalytic performance via surface decorating the Cu₂O catalyst with palladium (Pd) clusters, which are expected to facilitate the hydrogenation of NO₃⁻ due to their strong affinity for hydrogen. The prepared catalyst exhibited a high NH₃ yield rate of 0.555 mmol h⁻¹ cm⁻² (2.79 mmol h⁻¹ mg⁻¹_catalyst) and a remarkable faradaic efficiency (FE) of 95.8%, which is attributed to the numerous heterointerfaces between Cu₂O and Pd clusters on the catalytic surface. Density functional theory calculations provided insights into the role of the newly introduced active sites in promoting NO₃RR, thereby explaining the superior activity of the Pd cluster-decorated Cu₂O catalyst. The formation of copper domains during the NO₃RR also suppressed the competing reaction, the hydrogen evolution reaction, which has led to increased NH₃ FE and NO₃RR activity over multiple catalytic cycles.

开发用于 NO ₃ ⁻ 还原反应（NO ₃ RR）的高选择性和活性电催化剂引起了人们的极大兴趣。在这里，我们通过用钯（Pd）簇对Cu ₂ O催化剂进行表面修饰来提高催化性能，这有望促进NO ₃ ⁻ 产率，为0.555 mmol h ⁻¹ cm ⁻² （2.79 mmol h ⁻¹ mg ⁻¹ _catalyst ）和高达 95.8% 的法拉第效率（FE），这归因于催化表面上 Cu ₂ O 和 Pd 簇之间的大量异质界面。密度泛函理论计算深入了解了新引入的活性位点在促进 NO ₃ RR 中的作用，从而解释了 Pd 簇修饰的 Cu ₂ O 催化剂的优异活性。 NO ₃ RR 过程中铜域的形成也抑制了竞争反应，即析氢反应，从而导致 NH ₃ FE 和 NO ₃ 增加多个催化循环的 RR 活性。