In order to resolve the pollution and waste caused by urea-rich wastewater, designing superior and stable earth-abundant catalysts for urea oxidation reaction (UOR) have always been attractive and urgent but still challenging. Herein, we report on a facile surface-engineering strategy of building hierarchical nickel hydroxide nanosheet@nanowire array on Ni foam (Ni(OH)(2) NS@NW/Ni foam) as anode material toward superior urea electrolysis. This Ni(OH)(2) based-catalyst with peculiar nanosheet@nanowire configuration just requires a small potential of 0.34 V (vs. SCE) to drive 10 mA cm(-2) in 1.0 M KOH with 0.33 M urea, which outperforms the one with pure nanosheet array architecture and even the commercial Pt/C catalyst. Further, a two-electrode electrolysis system is built here with the cathode of cobalt phosphide nanowire array on Ni foam (Co2P NW/Ni foam) and anode of Ni(OH)(2) NS@NW/Ni foam for overall urea electrolysis, which needs a low voltage of 1.58 V to drive 5 mA cm(-2) in 1.0 M KOH with 0.33 M urea. Note that, the current density presented in this work is based on the real surface area of Ni foam but not the geometric area, unless otherwise specified. (c) 2018 Elsevier Ltd. All rights reserved.