Copper Foam‐Supported Cu ₂ O/Cu Heterostructure Nanowires for Electrocatalytic Reduction of Low‐Concentration Nitric Oxide to Ammonia

The electrocatalytic reduction of nitric oxide (NORR) to ammonia (NH ₃ ) offers a promising route for both pollutant remediation and the sustainable production of high‐value chemicals. However, NORR remains kinetically challenging due to the intense competition between side reactions and the difficulty in enriching NO under low‐concentration conditions. Herein, the copper foam‐supported Cu ₂ O/Cu heterostructure nanowires (Cu ₂ O/Cu NWs/CF) are developed as an efficient catalyst for low‐concentration NORR (a volume ratio of 1% NO). Comprehensive characterizations and electrochemical analyses reveal that the heterogeneous interface of Cu ₂ O/Cu NWs/CF effectively regulates the electronic structure of active sites, thereby optimizing the adsorption and activation of NO. Meanwhile, the heterostructure nanowires enlarge the electrochemical active surface area and promote the NO enrichment and mass transport. As a result, Cu ₂ O/Cu NWs/CF delivers excellent NORR performance with NH ₃ Faradaic efficiency up to 90.3% and a high NH ₃ yield rate of 323.8 μg h ⁻¹ cm ⁻² at −0.3 V versus reversible hydrogen electrode (RHE), outperforming control samples and most previously reported catalysts. Integrated into a Zn‐NO battery, Cu ₂ O/Cu NWs/CF exhibits a peak power density of 3.4 mW cm ⁻² and a desirable NH ₃ yield rate (367.1 μg h ⁻¹ cm ⁻² ). This work highlights a propitious direction for simultaneous energy supply, NO removal, and NH ₃ production.