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

Urea electrooxidation reaction (UOR) plays an importantrole inenvironmental protection and energy regeneration. The extensivelystudied nickel-based catalysts exhibit good activity for UOR, buturea is more prone to be overelectrooxidized to another pollutantNO( x ) (-) (x = 2, 3). Herein, the Cu/Ni-B interface catalyst is presented. Theintroduction of Cu significantly enhances the Faradaic efficiencyof N-2 (nearly 70% at 1.70 V versus RHE). Electrochemicaltests and in situ Raman spectroscopy results show that the introductionof Cu significantly affects the density of OH* species on the catalystin the UOR process. It is proposed that with a moderate decrease inOH* density, the catalyst can provide enough sites for urea moleculesto allow simultaneous adsorption of the two N atoms, facilitatingthe process of N-N coupling to form N-2. This work is alsoinstructive for the design of electrocatalysts for other nucleophileelectrooxidation reactions.

Automated summary

Cu/Ni-B interface catalysts improve the efficiency of ureaelectrooxidation and promote the formation of N-2. This study isinstructive for the design of electrocatalysts for other nucleophileelectrooxidation reactions.