Highly Selective Electrooxidation of Urea to Nitrogen on Copper/Nickel Boride Interface under Alkaline Condition

• Published in: Industrial & engineering chemistry research 2023-06, Vol.62 (22), p.8736-8743
• Main Authors: Shen, Zhichao, Qi, Yanbin, Ge, Wangxin, Jiang, Hongliang, Li, Chunzhong
• Format: Article
• Language: English
• Subjects: Materials and Interfaces
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.3c00802

Urea electrooxidation reaction (UOR) plays an important role in environmental protection and energy regeneration. The extensively studied nickel-based catalysts exhibit good activity for UOR, but urea is more prone to be overelectrooxidized to another pollutant NO x – (x = 2, 3). Herein, the Cu/Ni-B interface catalyst is presented. The introduction of Cu significantly enhances the Faradaic efficiency of N2 (nearly 70% at 1.70 V versus RHE). Electrochemical tests and in situ Raman spectroscopy results show that the introduction of Cu significantly affects the density of OH* species on the catalyst in the UOR process. It is proposed that with a moderate decrease in OH* density, the catalyst can provide enough sites for urea molecules to allow simultaneous adsorption of the two N atoms, facilitating the process of N-N coupling to form N2. This work is also instructive for the design of electrocatalysts for other nucleophile electrooxidation reactions.