Expanding Two‐Dimensional Electrochemical Window Enables Durable Copper‐Based Electrocatalysts for Nitrate‐to‐Ammonia Conversion

S Shiyu Zhang (Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohios 43210, United States) C Changhao Liu (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) J Jingwen Jiang (West China School of Public Health and West China Fourth Hospital) W Wangxi Liu (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) Z Zhexing Lin (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) Z Zhetong Yang (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) Y Yinggang Guo (National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Nanjing 210093 P.R. China) B Bin Gao (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) J Jianyong Feng (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) Z Zhigang Zou (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China) Z Zhaosheng Li (National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China)

Abstract

Abstract The excessive presence of nitrate pollution in water poses a persistent challenge. Electrochemical nitrate reduction offers a potential approach to address this issue but lacks effective electrocatalysts. Despite being promising electrocatalysts for nitrate reduction to ammonia, copper‐based oxides undergo an evolution process that is poorly understood, while also demonstrating poor stability. Herein, we discovered a two‐dimensional electrochemical window of copper‐based oxide electrocatalysts, influenced not only by the bias potential but also by the nitrate concentration. We expand the two‐dimensional stable operation window of Cu 2 O 1−δ with Ru single‐atom modification and Ni buffer doping, thus achieving a record robust electrocatalyst Ru 1 @(Cu,Ni) 2 O 1−δ for nitrate‐to‐ammonia conversion over 11 000 h at a high current density of 1.6 A cm −2 . Utilizing this electrocatalyst, we designed a hundred‐watt‐scale membrane electrode assembly electrolyzer for the conversion of nitrate to ammonia that can be operated at an industrial‐grade current density of 400 mA cm −2 and a cell voltage of 1.5 V (with a total current of 80 A, 120 W). Furthermore, we developed a solar‐powered integrated system that facilitates the daily synthesis of liquid ammonia at the hundred‐gram scale from wastewater alongside potable water purification.

Article Details

Volume / Issue Vol. 65, Issue 4
Published January 22, 2026
ISSN 1433-7851
Publisher Wiley

Journal Info

Angewandte Chemie International Edition

Wiley

ISSN: 1433-7851 Physical Sciences

Authors (11)

S

Shiyu Zhang

Department of Chemistry & Biochemistry, The Ohio State University, 100 West 18th Avenue, Columbus, Ohios 43210, United States

C

Changhao Liu

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

J

Jingwen Jiang

West China School of Public Health and West China Fourth Hospital

W

Wangxi Liu

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

Z

Zhexing Lin

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

Z

Zhetong Yang

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

Y

Yinggang Guo

National Laboratory of Solid State Microstructures College of Engineering and Applied Sciences Nanjing University Nanjing 210093 P.R. China

B

Bin Gao

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

J

Jianyong Feng

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

Z

Zhigang Zou

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China

Z

Zhaosheng Li

National Laboratory of Solid State Microstructures, College of Engineering and Applied Sciences, Nanjing University, 22 Hankou Road, Nanjing 210093, China