Nitrogen-coordinated single Fe sites for efficient electrocatalytic N2 fixation in neutral media

Electrocatalytic nitrogen reduction reaction (NRR) for NH3 generation under ambient conditions presents a promising alternative to the conventional Haber-Bosch process. Here, we report a Fe single-atom catalyst for ambient electrochemical NH3 synthesis. This catalyst achieves high Faradaic efficiency (18.6 +/- 0.8%) and NH3 yield rate (62.9 +/- 2.7 mu g h(-1) mg(cat).(-1)) in neutral aqueous electrolyte at room temperature and -0.4 V versus reversible hydrogen electrode. Furthermore, this catalyst exhibits a negligible activity decay during electrolysis for 24 h. X-ray absorption fine structure analyses and theoretical calculations reveal that atomically dispersed single Fe species are stabilized by N in Fe-N4 configuration, which is favorable for N-2 activation. This work opens new opportunities for developing advanced single atomic site catalysts for NH3 synthesis via NRR.