Hierarchical Ni-Mo-P nanoarrays toward efficient urea oxidation reaction

The urea oxidation reaction (UOR), which possesses a low theoretical potential and superior kinetics, is an attractive substitute for the anodic oxygen evolution reaction (OER) in overall water splitting; however, the implementation of hydrogen production in overall urea splitting is impeded by the deficiency of highly efficient, durable and cost-effective catalysts. Herein, we fabricated an Ni₂P-MoP₂ heterostructure with a hierarchical structure grown on carbon paper (Ni-Mo-P/CP), which exhibited robust activity and outstanding durability for the electrocatalytic oxidation of urea. The Ni-Mo-P/CP catalyst possessed an ultralow potential of 1.39 V to obtain the current density of 100 mA cm^-2, small Tafel slope (27 mV dec^-1) and long-term durability with almost no decay within 15 h. The experimental characterization revealed that the optimized electronic structure and the synergistic effect of abundant exposed active sites in the Ni-Mo-P/CP catalyst contribute to the efficient UOR catalytic activity. This work enriches the candidate catalysts for the UOR and promotes the industrial development of hydrogen production.