Synergistic AuRu nanoparticles on in-situ-grown 3D Cu₂O nanowires for enhanced ammonia production via photo-assisted electrocatalytic nitrate reduction

Electrocatalytic nitrate reduction to ammonia (NO₃RR) offers a promising sustainable pathway for ammonia synthesis while mitigating nitrate pollution using renewable electricity. However, in neutral electrolytes, this process suffers from low ammonia yield and selectivity due to limited adsorption and conversion efficiency of reaction intermediates. Here, we report a novel AuRu nanoparticles decorated three-dimensional Cu₂O nanowire catalyst, in situ synthesized on a copper foam substrate via a facile chemical impregnation method. Through optimized reaction pathways and synergistic bimetallic modulation of surface electron distribution, the catalyst achieves an impressive ammonia yield of 9.09 mg h⁻¹ cm⁻² in neutral electrolytes. Furthermore, under light irradiation, the catalytic performance was enhanced to 10.72 mg h⁻¹ cm⁻², attributed to the localized surface plasmon resonance (LSPR) effect of Au nanoparticles. This effect optimizes the surface electric field, enhancing the adsorption polarity of NO₃⁻ and thereby promoting highly efficient NO₃RR. These findings highlight the potential of plasmon-enhanced electrocatalysis for sustainable ammonia production.