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Nanoporous Ni Cu P amorphous alloy (NPA NiCuP) and nanoporous Ni Cu crystalline alloy (NP NiCu) have been prepared by potentiostatic etching of copper from the electroless Ni Cu P and Ni Cu alloy platings, respectively. The results of X-ray Diffraction (XRD), Energy Dispersion Spectrum (EDS) and Scanning Electron Microscopy (SEM) indicate that the NPA–NiCuP alloy is amorphous structure and shows a porous network structure with the pore size of 100–300 nm. The electrocatalytic oxidation of hydrazine in alkaline media is investigated by cyclic voltammetry (CV) and double potential step chronoamperometry (DPSCA). The results suggest that the proton diffusion coefficient of redox species and the reaction rate constant of the NPA–NiCuP alloy electrode in KOH solution are higher than those of the smooth electroless Ni Cu P amorphous (SA–NiCuP) and NP–NiCu alloy electrodes. In addition, the NPA–NiCuP electrode has higher anodic oxidation peak current density and lower onset oxidation potential of hydrazine in KOH solution than the SA–NiCuP and NP–NiCu electrodes. Finally, the CV measurement suggests that the NPA–NiCuP electrode has a relatively stable redox behavior. [ABSTRACT FROM AUTHOR]

Nanoporous Ni-Cu-P amorphous alloy (NP-NiCuP) and nanoporous Ni-Cu crystalline alloy (NP-NiCu) are prepared by the linear sweep voltammetry (LSV) etching of copper from the electroless Ni-Cu-P and Ni-Cu alloy coatings, respectively. The results of X-ray diffraction (XRD) analysis show that the nanoporous Ni-Cu-P alloy is amorphous structure. The scanning electron microscopy (SEM) analysis demonstrates the NP-NiCuP shows a 3-D bi-continuous porous structure with the pore size of 150–200 nm and the ligament size of around 100 nm. Electrochemical performances are measured by cyclic voltammetry (CV) and chronoamperometry (CA). The results prove that the NP-NiCuP electrode exhibits higher the proton diffusion coefficient ( D 0 ) of Ni(OH) 2 and surface coverage ( Γ * ) of the redox species than those on smooth electroless Ni-Cu-P amorphous alloy (S-NiCuP) and NP-NiCu electrodes in alkaline solution obviously. Moreover, electro-oxidation of methanol suggests that the NP-NiCuP electrode holds higher anodic current density and lower onset potential than the S-NiCuP and NP-NiCu electrodes. Finally, the NP-NiCuP electrode has stable redox behavior and superior catalytic stability for methanol oxidation. [ABSTRACT FROM AUTHOR]