Nickel nanowire arrays electrode as an efficient catalyst for urea peroxide electro-oxidation in alkaline media

•Self-supporting nickel NWAs electrode was templated electroformed.•The reaction pathways of urea peroxide electro-oxidation were raised.•The KOH and urea peroxide concentrations were optimized.•Nickel NWAs electrode shows high stability and activity towards urea peroxide. Urea peroxide as a solid-state fuel instead of liquid hydrogen peroxide is electro-catalytic oxidized by nickel nanowire arrays (NWAs) electrode. Nickel NWAs electrode is prepared by galvanostatically electrodepositing nickel into the pores and over-plating on the surface of polycarbonate template (PCT) from nickel bath solution. The NWAs are obtained after dissolving PCT in methylene chloride. Results show that urea peroxide decomposes into hydrogen peroxide and urea in aqueous solutions, then is electro-oxidized via two processes: i, hydrogen peroxide electro-oxidation at lower potential region; ii, both hydrogen peroxide and urea electro-oxidation at higher potential region. The onset oxidation potential and current density of urea peroxide electro-oxidation in 6.0molL−1 KOH and 1.0molL−1 urea peroxide are ca. -0.2V and 700mAcm−2 at 0.6V, respectively. The nickel NWAs electrode demonstrates excellent stability for urea peroxide electro-oxidation under different polarization potentials.