Issue 28, 2025

Self-evolution induced CuxO/Fe3O4 heterogeneous interfaces enabling rapid nitrate reduction to ammonia

Abstract

The electrocatalytic nitrate reduction reaction (eNO3RR) is a promising approach for sustainable ammonia (NH3) synthesis and wastewater treatment. In this work, a carbon-loaded Cu/Fe metal catalyst (Cu5Fe@NC) was synthesized via a solvothermal method followed by high-temperature carbonization. Electrochemically induced surface reconstruction led to the formation of a highly active CuxO/Fe3O4 heterojunction interface, which synergistically enhanced NO3 adsorption, facilitated electron and proton transfer, and accelerated the overall eNO3RR process. Electrochemical tests revealed that the Cu5Fe@NC catalyst exhibited excellent performance at an optimal potential of −0.7 V vs. RHE, achieving a NO3 removal efficiency of 98.93%, NH4+ selectivity of 92.61%, and a faradaic efficiency of 81.58%. The catalyst maintained 92% of its initial performance even after five consecutive electrolysis cycles, indicating remarkable durability and stability. In situ spectroscopic analysis and density functional theory (DFT) calculations further revealed the reaction mechanism. At the CuxO/Fe3O4 heterojunction interface, NO3 was adsorbed via a bridging mode, followed by a tandem reduction process, where NO2 migrated to the Fe3O4 surface, underwent hydrogenation, and ultimately converted into NH3. Gibbs free energy calculations confirmed that the CuxO/Fe3O4 interface significantly reduced the activation energy barrier for NH3 formation compared to Cu2O. This work provides valuable insights into the rational design of high-performance electrocatalysts for efficient nitrate reduction and sustainable ammonia production.

Graphical abstract: Self-evolution induced CuxO/Fe3O4 heterogeneous interfaces enabling rapid nitrate reduction to ammonia

Supplementary files

Article information

Article type
Paper
Submitted
22 Apr 2025
Accepted
18 Jun 2025
First published
20 Jun 2025

J. Mater. Chem. A, 2025,13, 23035-23045

Self-evolution induced CuxO/Fe3O4 heterogeneous interfaces enabling rapid nitrate reduction to ammonia

Y. Xia, X. Li, Y. Qu, Y. Zhou, Z. Weng, S. Jin, J. Wang and X. Chang, J. Mater. Chem. A, 2025, 13, 23035 DOI: 10.1039/D5TA03155A

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements