Antimony‐Based Composites Loaded on Phosphorus‐Doped Carbon for Boosting Faradaic Efficiency of the Electrochemical Nitrogen Reduction Reaction

Abstract

A nanocomposite of PC/Sb/SbPO₄ (PC, phosphorus-doped carbon) exhibits a high activity and an excellent selectivity for efficient electrocatalytic conversion of N₂ to NH₃ in both acidic and neutral electrolytes under ambient conditions. At a low reductive potential of -0.15 V versus the reversible hydrogen electrode (RHE), the PC/Sb/SbPO₄ catalyst achieves a high Faradaic efficiency (FE) of 31 % for ammonia production in 0.1 m HCl under mild conditions. In particular, a remarkably high FE value of 34 % is achieved at a lower reductive potential of -0.1 V (vs. RHE) in a 0.1 m Na₂ SO₄ solution, which is better than most reported electrocatalysts towards the nitrogen reduction reaction (NRR) in neutral electrolyte under mild conditions. The change in surface species and electrocatalytic performance before and after N₂ reduction is explored by an ex situ method. PC and SbPO₄ are both considered as the active species that enhanced the performance of NRR.