Publication
Cuprous oxide (Cu2O) materials are the most promising copper-based catalysts for electrochemical nitrate (NO3[sbnd]) reduction to ammonia (NH3). Nevertheless, adsorption for N[sbnd]containing intermediates (NO3[sbnd], NO2[sbnd], etc.) is too[sbnd]strong, and combined with their limited hydrogenation capacity, reduces their capacity for efficient NH3 synthesis via alkaline electrochemical NO3[sbnd] reduction reactions (eNO3[sbnd]RR). Herein, we present a Cu2O catalytic electrode incorporating iron with a pyramid[sbnd]like structure, fabricated on a copper foam (CF) matrix, obtained through an “electroplating[sbnd]oxidation[sbnd]electroreduction” (E[sbnd]O[sbnd]E) strategy. The incorporation of Fe regulates the local charge modulation environment and micromorphology of the Cu2O, creating Fe3+ and Cu+ dual active sites in the Cu2O/CF that accelerate the rate of hydrogenation. Calculations reveal that the incorporated Fe3+ shift the d[sbnd]band center of Cu2O to the Fermi level and decrease the adsorptive free energies of bound N[sbnd]containing intermediates, facilitating the eNO3[sbnd]RR reaction. The optimal Fe[sbnd]Cu2O catalyst exhibits excellent performance in the eNO3[sbnd]RR, achieving an NH3 yield rate of 10.27 mg h[sbnd]1 cm[sbnd]2 and a FE reaching 93.05 %. The catalytic performance remains stable at [sbnd]0.3 V vs. RHE for 20 h under alkaline conditions, implying its outstanding durability. Consequently, this work highlights the potential of dual active sites via heteroatomic incorporation to boost the eNO3[sbnd]RR process and provides new insights for developing advanced electrocatalysts.