Coupling Cathodic Nitrate Reduction With Anodic Polymer Oxidation Enabled by Bimetallic FeNi Nanoalloys at Low Potentials

ABSTRACT

The electrocatalytic reduction of NO ₃ ⁻ coupled with the oxidation of polyacrylamide (HPAM) represents a novel electrocatalytic reaction system with broad prospects. However, its overall efficiency remains insufficient and the reaction potential excessively high, limiting further application. By reconfiguring the surface charge distribution, we achieved enhanced electrochemical efficiency and reduced the applied reaction potential. This study synthesized a bifunctional FeNi@N‐CNTs catalyst with a heterojunction structure, achieving a maximum ammonia production rate of 13.74 ± 0.11 mg h ⁻¹ mg _cat. ⁻¹ and a Faradaic efficiency of 88.82 ± 0.93%. Furthermore, the HPAM degradation efficiency reached 96.04 ± 0.82% within 2 h at − 0.6 V (vs. RHE). Finally, in situ ATR–SEIRAS and in situ DEMS analyses revealed that *NHOH serves as a crucial reaction intermediate in the ammonia synthesis process. This work provides novel insights for advancing the industrial application of electrocatalytic NO ₃ ⁻ reduction coupling.