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

Abstract

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 μg h−1 mgcat.−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 N2 activation. This work opens new opportunities for developing advanced single atomic site catalysts for NH3 synthesis via NRR.