Low‐Voltage Driven Co‐Production of Ammonia, Formate, and Hydrogen From Nitrite Reduction Coupled Formaldehyde Oxidation System on Ultra‐Stable AuCuRh Nanowires under Illumination

The nitrite electroreduction reaction (NO₂RR) offers a green and sustainable pathway for environmental wastewater treatment and ammonia (NH₃) generation. Herein, defect-rich trimetallic AuCuRh nanowires (AuCuRh NWs) with a large number of grain boundaries, twin boundaries, and atomic steps are successfully synthesized by galvanic replacement reaction. Due to its self-stability and high activity, AuCuRh NWs can efficiently drive the stable NO₂RR at 0 V potential (Faradaic efficiency: 98.32%, NH₃ yield rate: 20.49 mg h^-1 mg_cat ^-1). Moreover, AuCuRh NWs also reveal excellent electrocatalytic activity for the formaldehyde electrooxidation reaction (FOR), which can reach 10 mA cm^-2 at only 0.35 V potential. The NO₂RR||FOR electrolysis system assembled with AuCuRh NWs requires only the electrolysis voltage of 0.38 V to achieve the co-production of NH₃, formate, and hydrogen and ultra-stable continuous electrolysis for 300 hours. The NO₂RR||FOR electrolysis system can be further decreased to only 0.29 V under illumination due to plasmon-enhanced activity. This study provides an energy-efficient coupling strategy for the stable co-production of value-added chemicals.