Single-atom Co alloyed Ru for electrocatalytic nitrite reduction to ammonia

Electrochemical converting NO 2 − into NH3 (NO2RR) holds an enormous prospect to attain efficient NH3 electrosynthesis and polluted NO 2 − mitigation. Herein, we report single-atom Co alloyed Ru (Co1Ru) as an efficient and durable NO2RR catalyst. Extensive experimental and theoretical investigations reveal that single-atom Co alloying of Ru enables the construction of Co1Ru heteronuclear active sites to synergistically promote NO 2 − activation/hydrogenation while suppressing the competitive H2 evolution, rendering the greatly enhanced activity and selectivity of Co1Ru towards the NO2RR. Consequently, Co1Ru assembled within a flow cell exhibits an impressive NH3 yield rate of 2379.2 µmol·h−1·cm−2 with an NH3-Faradaic efficiency of 92% at a high current density of 415.9 mA·cm−2, which is among the highest NO2RR performances reported to date.