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 yield 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.