Formation of nanoporous NiCuP amorphous alloy electrode by potentiostatic etching and its application for hydrazine oxidation

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.