Phase-separated CuAg alloy interfacial stress induced Cu defects for efficient N2 activation and electrocatalytic reduction

The electrochemical nitrogen reduction reaction (eN2RR) to produce ammonia represents a promising approach to substitute the traditional Haber-Bosch process. However, it remains challenging due to the low ammonia yield caused by low Faradic Efficiency over the target intermediates. Herein, the adjacent Cu defect formed at the interface of phase-separated CuAg alloy was successfully prepared by using the cation-exchange method and identified as the most active electrocatalytic center for efficient N2 reduction. The phase-separated CuAg alloy with rich interfacial Cu defective sites exhibited excellent eN2RR performance with an ammonia production rate (38.35 µg h−1 cm−2) and a Faradaic efficiency of 12.72 % at − 0.60 V versus reversible hydrogen electrode. Our work unravels fundamental principles for the rational design of electrocatalysts, and provides a strategy for fabricating the CuAg-PS alloy with rich interfacial Cu defective sites for eN2RR.