Oxygen-Bridged Copper-Iron Atomic Pair as Dual-Metal Active Sites for Boosting Electrocatalytic NO Reduction.

Electrocatalytic reduction of nitric oxide (NO) to ammonia (NH 3 ) is a promising approach to NH 3 synthesis. However, due to the lack of efficient electrocatalysts, the performance of electrocatalytic NO reduction reaction (NORR) is far from satisfactory. Herein, we report that an atomic copper-iron dual-site electrocatalyst bridged by an axial oxygen atom (O-Fe-N 6 -Cu) is anchored on nitrogen-doped carbon (CuFe DS/NC) for NORR. The CuFe DS/NC can significantly enhance the electrocatalytic NH 3 synthesis performance (Faraday efficiency, 90%; yield rate, 112.52 μmol cm -2 h -1 ) at -0.6 V versus RHE, which is dramatically higher than the corresponding Cu single-atom, Fe single-atom and all NORR single-atom catalysts in the literature so far. Moreover, an assembled proof-of-concept Zn-NO battery using CuFe DS/NC as the cathode outputs a power density of 2.30 mW cm -2 and NH 3 yield of 45.52 μg h -1 mg cat -1 . The theoretical calculation result indicates that bimetallic sites can promote electrocatalytic NORR by changing the rate-determining step and accelerating the protonation process. This work provides a flexible strategy for the efficient sustainable NH 3 synthesis. This article is protected by copyright. All rights reserved.