Precious-Group-Metal-Free Energy-Efficient Urea Electrolysis: Membrane Electrode Assembly Cell Using Ni3N Nanoparticles As Catalyst

The sluggish kinetics of the anodic oxygen evolution reaction (OER) limit the overall efficiency of green hydrogen production. The proposed strategy to overcome this is to replace OER with other kinetically favorable anodic reactions like urea oxidation reaction (UOR). Herein, we develop an organometallic synthesis of nickel nitride nanoparticles supported on carbon (Ni3N-C) as the catalyst for both UOR and hydrogen evolution reaction (HER). A precious group metal-free electrolyzer based on Ni3N-C catalyst (as both anode and cathode) is implemented for the first time, and the urea electrolyzer cell has a 200 mV lower overpotential compared to that of the water electrolyzer.