Synergistic Regulation of Intermediate Conversion and Activated Hydrogen Supply on Fe-Ru Diatomic Sites Drives Efficient Electroreduction of Neutral Nitrate to Ammonia

Abstract

Table of Contents EntryThe FeRuSA NC can not only precisely regulate the initial adsorption and the subsequent rate-determining hydrogenation step, but also modulate the interfacial water structure (enriched K-H 2 O) to promote water dissociation and provide sufficient active hydrogen. This synergistic effect enables efficient nitrate electroreduction to ammonia with exceptional yield rate and selectivity.Highlights A Fe-Ru diatomic catalyst (FeRuSA NC) is rationally designed and successfully prepared to precisely regulate the kinetics of eNO 3 RR by integrating Fe and Ru single atoms anchored on N-doped carbon substrate.  The Fe-Ru diatomic sites concurrently reduce the energy barriers of the initial adsorption and the subsequent rate-determining hydrogenation step, thereby facilitating the reduction of NO 3 ⁻ to NO 2 -and subsequent hydrogenation to NH 3 .  The Fe-Ru diatomic sites facilitate water dissociation by modulating interfacial water environment (enriched K-H 2 O), suppling sufficient *H to drive the deep hydrogenation of nitrogen containing intermediates. FeRuSA NC delivers an exceptional NH 3 yield rate of 1.99 mmol h -1 mg cat. -1 and a high Faradaic efficiency of 96.8% at -1.2 V vs. RHE, significantly outperforming its monometallic counterparts and the previouly reported Fe-SACs catalysts.