电化学法制备Ni-W-P纳米线阵列电极及其催化析氢性能

摘要

采用二次氧化法制备了多孔阳极氧化铝(AAO)模板,通过控制电位沉积技术在AAO模板内组装了Ni-W-P合金纳米线阵列.在扫描电子显微镜(SEM)下观察到Ni-W-P纳米线表面光滑,长约20 μm,直径均匀(约为100 nm),与AAO模板孔径基本一致.阴极极化曲线和交流阻抗图谱(EIS)的测试结果表明,Ni-W-P合金纳米线阵列电极析氢反应(HER)电阻减小,具有更高的催化析氢活性,电流密度为10 mA·cm-2时,析氢极化电位较Ni-W-P合金电极正移约250 mV.%A Ni-W-P alloy nanowire array was fabricated in the nanochannels of an aluminum anodic oxide (AAO) membrane by electrodeposition. Scanning electron microscopy (SEM) was used to characterize the morphology of the Ni-W-P nanowire arrays. These nanowires had uniform diameters of about 100 nm and this accorded with the diameters of the holes. The length of these nanowires was about 20 μm. Cathodic polarization curves and electrochemical impedance spectroscopy (EIS) were used to study the electrocatalytic activity of the electrodeposited Ni-W-P alloy for the hydrogen evolution reaction (HER). The results clearly showed that the Ni-W-P alloy nanowire array electrodes had the highest electrocatalytic activity for the HER and the overpotential was lowered by 250 mV at 10 mA · cm-2 compared with the as-electroplated Ni-W-P alloy.