Single-atom tungsten doping induced chemical–electrochemical coupled pathway on Ni(OH) 2 enables efficient urea electrooxidation

• Published in: Energy & environmental science Vol. 18; no. 5; pp. 2415 - 2425
• Main Authors: Cai, Lebin, Bai, Haoyun, Li, Jilong, Xie, Feng, Jiang, Kang, Lu, Ying-Rui, Pan, Hui, Tan, Yongwen
• Format: Journal Article
• Language: English
• Published: Cambridge Royal Society of Chemistry 04.03.2025
• Subjects: Catalysts; Electrochemistry; Electron transfer; Energy recovery; Evolution; Intermediates; Nickel compounds; Oxidation; Oxygen evolution reactions; Tungsten; Urea
• ISSN: 1754-5692; 1754-5706
• DOI: 10.1039/D4EE05340K

The electrocatalytic urea oxidation reaction (UOR) has emerged as a promising alternative to the oxygen evolution reaction (OER) for wastewater recycling and energy recovery. However, the traditional UOR pathway on NiOOH surface is hindered by the rate-limiting desorption of *COO and the competition between the UOR and OER. In this study, we propose a chemical–electrochemical coupled pathway for the direct UOR, achieved through the construction of a single-atom W-doped nanoporous P–Ni(OH) 2 catalyst (np/W–P–Ni(OH) 2 ). Specifically, the np/W–P–Ni(OH) 2 catalyst exhibits exceptional UOR performance with an ultralow potential of 1.28 V vs. RHE to reach 10 mA cm −2 and a high UOR selectivity exceeding 90% across the entire potential range. A collection of in situ spectroscopies and theoretical calculations reveal that single-atom W dopants not only accelerate the formation of Ni(OH)O active intermediates by modulating the O charge in the lattice hydroxyl, but also lower the energy barrier of the proton-coupled electron transfer step and the cleavage of the C–N bond, thus realizing the highly efficient UOR.