Highly efficient urea-anodizing to promote the electrochemical nitrogen reduction process

Abstract

Herein, we have developed a functionally integrated strategy that replaces water with much readily oxidized urea to promote the electrochemical N₂ fixation. A durable robust electrocatalyst, a MOF-driven C, N-codoped nanoarray grown on nickel foam, namely CuO/Cu₂O@CD-CN/NiF, serves as both the cathode and anode for the N₂ reduction and urea oxidation. It is significant that an NH₃ yield rate of 102.2 μg h⁻¹ cm⁻² and a faradaic efficiency of 23.9% were obtained, significantly exceeding those of its urea-free counterpart. This research not only provides value to the future artificial nitrogen fixation to ammonia but also opens up new avenues for the replacement of the sluggish oxygen evolution reaction (OER) for energy-efficient NH₃ generation.