Carbon Nanotubes‐Supported Intermetallic CuPd Nanocrystals for Efficient Electrochemical Nitrate Reduction to Ammonia Integrated With Energy and Resource Recycling Strategies

The discharge of nitrate wastewater has caused severe environmental problems along with accelerated industrialization. Electrocatalytic nitrate reduction reaction (NO 3 RR) has emerged as a pivotal technology integrating pollution remedy and resource recovery. In this study, palladium is prescreened as the optimal noble metal for doping into the copper lattice via DFT prediction. The carbon nanotubes‐supported intermetallic CuPd (CuPd‐CNTs) nanocrystals (mean size 10.78 ± 1.72 nm) are synthesized through a one‐step hot‐injection method. Pd‐doping optimizes the catalytic process by regulating intermediate adsorption behavior and electronic structure, and CNTs effectively inhibit metal oxidation and enhance electron transfer efficiency. Electrochemical measurements demonstrate that CuPd‐CNTs exhibit excellent NO 3 RR performance with low onset potential, Tafel slope, and charge transfer resistance, achieving a high Faradaic efficiency of ∼95% for NH 3 production with good stability. In situ FTIR and Raman spectroscopy combined with differential electrochemical mass spectrometry clarify that the critical reaction pathway goes through the first hydrogenation step from *NO to *NOH. Notably, an aluminum‐nitrate galvanic system using CuPd‐CNTs achieves an open‐circuit potential of 1.209 V and a peak power density of 5.46 mW cm −2 , and exhibits excellent operational stability, realizing the synergy of nitrate degradation, ammonia production, electrical energy output, and waste aluminum resource recovery.