Rational design of asymmetric atomic Ni-P 1 N 3 active sites for promoting electrochemical CO 2 reduction

The atomic-level interfacial regulation of single metal sites through heteroatom doping can significantly improve the characteristics of the catalyst and obtain surprising activity. Herein, nickel single-site catalysts (SSCs) with dual-coordinated phosphorus and nitrogen atoms were developed and confirmed (denoted as Ni-P x N y , x = 1, 2 and y = 3, 2). In CO 2 reduction reaction (CO 2 RR), the CO current density on Ni-P x N y was significantly higher than that of Ni-N 4 catalyst without phosphorus modification. Besides, Ni-P 1 N 3 performed the highest CO Faradaic efficiency (FE CO ) of 85.0%–98.0% over a wide potential range of −0.65 to −0.95 V (vs. the reversible hydrogen electrode (RHE)). Experimental and theoretical results revealed that the asymmetric Ni-P 1 N 3 site was beneficial to CO 2 intermediate adsorption/desorption, thereby accelerating the reaction kinetics and boosting CO 2 RR activity. This work provides an effective method for preparing well-defined dual-coordinated SSCs to improve catalytic performance, targetting to CO 2 RR applications.