Low-overpotential, self-driving Fe-Mn co-doped nickel foam for highly efficient electrocatalytic oxidation of amines to nitriles

Electrocatalytic synthesis of high value-added nitrile from amines provides a green, sustainable, and cost-effective strategy. However, achieving high electrocatalytic efficiency often requires significant energy consumption. In this work, we designed a bimetallic co-doped Fe-Mn/NF electrocatalyst through a simple one-step hydrothermal process and utilized it for the electrocatalytic oxidation of benzylamine to produce benzonitrile. The current density of 10 mA cm⁻² in the 0.5 M KOH electrolyte can be achieved with the voltage of only 1.34 V vs. reversible hydrogen electrode (RHE). The efficient electrocatalytic activity is mainly attributed to the synergistic effect and Jahn–Teller effect of the doped Fe and Mn within the Nickel Foam (NF) materials, thus promoting the formation of the active intermediate Ni³⁺ (NiOOH). Meanwhile, the in situ characterization confirmed the presence of NiOOH during the electrocatalytic oxidation. Notably, the benzonitrile and hydrogen, as products, can be automatically separated from the electrocatalytic system, providing a positive self-driving force for the electrocatalytic reaction. Thus, the Fe-Mn/NF electrocatalyst exhibits excellent catalytic performance, and the Faraday efficiency for benzonitrile synthesis exceeds 98 %. This work provides valuable insights for developing electrocatalysts that combine high catalytic efficiency with low energy consumption for the electrocatalytic synthesis of nitrile compounds.