Boosting ammonia production in electrocatalytic NOx reduction on a robust Fe/FeMoO4 catalyst

Electrocatalytic reduction of nitrate \(({\rm{N}}{{\rm{O}}_3}^ - )\) and nitride \(({\rm{N}}{{\rm{O}}_2}^ - )\) to ammonia (NH 3 ) is of wide interest as a promising alternative to the energy-intensive Haber-Bosch route for mitigating the vast energy consumption and the accompanied carbon dioxide emission, as well as benefiting for the relevant sewage treatment. However, exploring an efficient and low-cost catalyst with high atomic utilization that can effectively facilitate the slow multi-electron transfer process remains a grand challenge. Herein, we present an efficient hydrogenation of \({\rm{N}}{{\rm{O}}_3}^ - /{\rm{N}}{{\rm{O}}_2}^ - \) species to NH 3 in both alkaline and neutral environments over the Fe 2 (MoO 4 ) 3 derived hybrid electrocatalyst with the metallic Fe site on FeMoO 4 (Fe/FeMoO 4 ). The Mo ingredient can play a synergistically positive role in further promoting the NH 3 production on Fe. As a result, Fe/FeMoO 4 behaves well in the electrochemical NH 3 generation from \({\rm{N}}{{\rm{O}}_2}^ - \) with a maximum NH 3 Faradaic efficiency (FE) of 96.53% and 87.68% in alkaline and neutral electrolyte, corresponding to the NH 3 yield rate of 640.68 and 302.56 \({\rm{mg}} \cdot {{\rm{h}}^{ - 1}} \cdot {\rm{m}}{{\rm{g}}_{{\rm{cat}}.}}^{ - 1}\) , respectively, which outperforms the Fe and Mo counterpart and other similar catalyst, showing the robust catalytic capacity of each active site.