In Situ Growth of Nitrogen-Doped Carbon-Coated γ-Fe₂O₃ Nanoparticles on Carbon Fabric for Electrochemical N₂ Fixation

Although electrocatalytic N 2 fixation has been regarded as a promising alternative strategy to the current Haber–Bosch technique for ammonia synthesis, it still remains a great challenge to develop low-cost and high-efficiency electrocatalysts with high catalytic activity and good selectivity. Here, we report the fabrication of a free-standing 3D hybrid electrode by in situ growth of N-doped carbon-coated γ-Fe 2 O 3 nanoparticles supported on carbon fabric (γ-Fe 2 O 3 -NC/CF), which manifests a high Faradaic efficiency (FE) of 12.28% and a considerable ammonia yield of 11.7 × 10 –10 mo1 s –1 cm –2 . Systematic characterization coupled with comprehensive electrochemical studies imply that the cation vacancies on the surface of γ-Fe 2 O 3 -NC/CF generated during the electrochemical activation process majorly contribute to the enhanced electrocatalytic activity for the nitrogen reduction reaction (NRR).