Efficient and stable electrocatalysts are essential for electrochemical denitrification of nitrate contamination in water. Herein, a cost-effective Cu₂O/Cu NRs/CF cathode bearing abundant Cu active sites and electron-rich Cu₂O sites with good atomic H* provision performance is reported to exhibit rapid nitrate reduction kinetics (0.04815 min⁻¹) and no nitrite accumulation. Benefiting from the enhanced mass transfer and sufficient H* provision, the rapid adsorption of *NO₃, fast reduction of *NO₂ to *NO, and highly selective *NO to *NOH transformation played critical roles in the electrochemical nitrate reduction process. Although ammonia was the main final nitrate reduction product, the electrocatalytic system we designed could effectively oxidize ammonia into N₂ with the assistance of simultaneous electrochlorination, finally achieving 96.81% of N₂ selectivity. Significantly, the long-term stability and low energy consumption to treat actual nitrate-contaminated wastewater make the Cu₂O/Cu NRs/CF electrode promising for practical applications.

高效稳定的电催化剂对于水中硝酸盐污染的电化学反硝化至关重要。在此，具有成本效益的Cu ₂ O/Cu NRs/CF 阴极具有丰富的Cu 活性位点和具有良好原子H* 提供性能的富电子Cu ₂ O 位点，据报道表现出快速的硝酸盐还原动力学（0.04815 min ^-1）和没有亚硝酸盐积累。得益于增强的传质和充足的 H* 供应，*NO 3 的快速吸附，*NO _2的快速还原到*NO，以及高选择性*NO 到*NOH 的转化在电化学硝酸盐还原过程中起关键作用。虽然氨是主要的最终硝酸盐还原产物，但我们设计的电催化系统可以在同步电氯化的帮助下有效地将氨氧化成 N ₂，最终实现了 96.81% 的 N ₂选择性。值得注意的是，处理实际硝酸盐污染废水的长期稳定性和低能耗使得Cu ₂ O/Cu NRs/CF电极具有实际应用前景。