Cascade Design and Facile Fabrication of Cu/Cu<sub>2</sub>O/CuAl‐Layered Double Hydroxides as Efficient Nitrate Reduction Electrocatalysts
Yajie Bai, Zhenyuan Fang, Kangkang Jia, Xianlei Jiang, Yiwei Gao, Chenxiao Lin, Denghui Ma, Jianming Li, Hong‐Ye Bai, Weiqiang Fan
Abstract
Abstract Nitrate (NO 3 ¯) reduction reaction (NITRR) presents a promising pathway for the production of renewable NH 3 while concurrently decontaminating NO 3 ¯ wastewater. However, the multi‐electron transfer sequence and complex reaction network involved in NO 3 ¯ conversion pose significant challenges to achieving high Faradaic efficiency ( FE ). Herein, this work presents ternary Cu/Cu 2 O/CuAl‐layered double hydroxides (LDHs) catalysts designed through a cascade approach and synthesized via a straightforward one‐step electrodeposition method. The resulting catalysts demonstrate peak activity at −0.4 V versus RHE, achieving an impressive of 92.0%, which significantly surpasses most reported binary and ternary catalysts. Density functional theory calculations and atomic force microscopy reveal that the Cu/Cu 2 O/CuAl‐LDHs exploit cascade design by integrating three distinct functions essential for efficient NO 3 ¯ reduction: CuAl‐LDH initiates NO 3 ¯ adsorption, Cu(111) and Cu₂O(111) cooperatively facilitate NO 3 ¯ activation, and Cu(111) promotes NH 3 desorption. Durability tests further confirm that both NH 3 yield and remain stable after 10 cycles, indicating the excellent stability of the Cu/Cu 2 O/CuAl‐LDHs catalysts. These findings underscore the critical role of cascade design strategies in enhancing the performance of electrocatalysts for NO 3 ¯ reduction to NH 3 , providing a transformative approach for sustainable ammonia synthesis.