Structural optimization of oxygen vacancies in WO3via Cu doping for enhanced electrocatalytic nitrate reduction to ammonia

Abstract

Electrochemical nitrate reduction to ammonia not only removes harmful nitrate pollutants from wastewater but also generates valuable ammonia. In this work, Cu was introduced into WO3, and high-concentration oxygen defects were generated using a simple hydrothermal method. Cu was then added as an electrocatalyst for nitrate reduction. In the doping process, Cu replaces the W atom in the WO3 structure. To maintain the charge balance, WO3 forms a higher concentration of oxygen vacancy (Ov) through the charge compensation mechanism. The abundant oxygen vacancy on the catalyst surface and the synergistic effect of Cu active sites promoted nitrate adsorption, resulting in improved NO3RR performance. Experimental results revealed that Cu–WO3 exhibited a high NH3 yield of 2131.3 μg h−1 mgcat−1 and a Faraday efficiency of 94% at a potential of −0.6 V (vs. RHE) in an alkaline electrolyte. 15N isotopic labeling tests confirmed the origin source of the produced ammonia. Cu–WO3 also exhibited excellent electrochemical cycle stability and long-term durability, suggesting its application in the industrial field. In situ Fourier-transform infrared (FTIR) spectroscopy revealed that Cu–WO3 can effectively adsorb nitrate and nitrogen dioxide intermediates. This work provides valuable insights for the exploration of efficient nitrate NO3RR electrocatalysts.

Graphical abstract: Structural optimization of oxygen vacancies in WO3 via Cu doping for enhanced electrocatalytic nitrate reduction to ammonia

Supplementary files

Transparent peer review

To support increased transparency, we offer authors the option to publish the peer review history alongside their article.

View this article’s peer review history

Article information

Article type
Research Article
Submitted
09 Feb 2025
Accepted
09 Jun 2025
First published
10 Jun 2025

Inorg. Chem. Front., 2025, Advance Article

Structural optimization of oxygen vacancies in WO3 via Cu doping for enhanced electrocatalytic nitrate reduction to ammonia

M. Wu, S. Li, K. Wei, H. Hu, Y. Song, Z. Zheng, H. Li and F. Gao, Inorg. Chem. Front., 2025, Advance Article , DOI: 10.1039/D5QI00388A

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