Study on the Electrodeposition of Ni-P Nanowires and Their Electrocatalytic Properties

The anodized aluminum oxide (AAO) template was used in the electrodeposition of Ni-P alloy in this study. The fabricated Ni-P wires were 70 to 80 nm in diameter and 15 to 20 μm in length. The analyses employing a field-emission scanning electron microscope, X-ray diffraction, transmission electron microscope, and X-ray photoelectron spectrometer (XPS) showed these nanowires were amorphous structure mixed with nanosized grains and had preferred orientation along its length. From the cathodic polarization measurements in 0.5M H₂SO₄ electrolyte, it was found that the Ni-P nanowires demonstrated a nearly double magnitude in the current at –0.75 V_SCE compared with its solid film counterpart. Thus, the enhancement of the electrocatalytic activity due to the increase in the surface area of the nanowired structure was demonstrated and discussed. However, the formation of oxide film on the surface of the nanowire was discovered after cathodic polarization. The effect of the oxide film was also discussed in this article.