Construction of Stable Cu-O-Fe Bridging Structure for Highly Efficient Electrocatalytic Nitrate Reduction to Ammonia

Abstract

Electrocatalytic conversion of nitrate to high-value ammonia (NH3) using renewable energy holds great significance for industrial applications. Herein, we report a high-activity Cu-Fe dual-site nanoflower-like catalyst (CuFe-CF) fabricated via one-step electrodeposition on copper foam (CF), which exhibits outstanding performance for the nitrate reduction reaction (NtrRR). X-ray absorption spectroscopy (XAS) characterizations confirm that CuFe-CF possesses a stable Cu-O-Fe bridged electronic structure. Benefiting from this unique structure, CuFe-CF achieves a remarkable Faradaic efficiency (FE) of 95.8 ± 1.0% for NH3 production at −0.6 V (vs. RHE), and an exceptional NH3 production rate of 102.3 ± 0.3 mg h⁻¹ cm⁻² at −1.2 V (vs. RHE). This work provides new insights for designing high-performance catalysts for nitrate reduction to ammonia.