Enhanced electrooxidation of urea using NiMoO4·xH2O nanosheet arrays on Ni foam as anode

Urea electrolysis has shown great potential in hydrogen production and remediation of urea-containing wastewater and it is highly important to develop efficient urea oxidation electrocatalysts made from earth-abundant elements. Here we report the growth of NiMoO4·xH2O nanosheet arrays on Ni foam (NiMoO4 NAs/NF) through a hydrothermal process. When directly used as a 3D catalytic anode for electrooxidation of urea in alkaline solutions, the NiMoO4 NAs/NF exhibits high catalytic activity and stability. It achieves specific current density of 830 mA cm−2 mg−1 at 0.5 V at a scan rate of 10 mV s−1, about 4.2 times enhancement compared to Ni(OH)2 NAs/NF.