Regioselective Doping into Atomically Aligned Core–Shell Structures for Electrocatalytic Reduction of Nitrate to Ammonia
Ying Zhang, Tianyi Gao, Fei Zhang, Xuelian Qu, Yutong Luo, P. Zhang, Jia Liang, Yun Song, Fang Fang, Fei Wang, Dalin Sun, Yang Liu
Abstract
Abstract The electrochemical nitrate reduction reaction (NO 3 − RR) presents an environmentally friendly approach for efficient NO 3 − pollutant removal and ammonia (NH 3 ) production, compared to the conventional Haber–Bosch approach. While core/shell engineering has demonstrated its potential in enhancing NO 3 − RR performance, significant synthetic challenges and limited shell layer modification capabilities impede the exploration of high‐performance NO 3 − RR core/shell catalysts. Herein, CuCoO/Co(OH) 2 core/shell structure via in situ electrochemical activation is synthesized. The catalyst delivers a maximum NH 3 Faradaic efficiency (FE) of 94.7% at −0.5 V RHE with excellent durability and selectivity for NH 3 over a wide range of potentials in NO 3 − RR, surpassing the electrocatalytic performance of both undoped shell and core components. The outstanding performance Cu─CoO/Co(OH) 2 is ascribed to the enhanced charge transfer, stabilization of key reaction intermediates, and regulation of hydrogen adsorption over Cu‐doped core/shell structure. Furthermore, the assembled Zn−NO 3 − battery device attains a peak current density exceeding 32 mA cm −2 and an NH 3 yield of up to 145.4 µmol h −1 cm −2 . The work offers a novel core/shell engineering strategy in electrocatalytic NO 3 − RR and sheds light on the doping effects on the electrochemical NH 3 synthesis.