模板法电化学共沉积Ni-Mo合金纳米线的研究

Codeposition of Ni-Mo Alloy Nanowires in Porous Anodic Alumina Templates

使用多孔阳极氧化铝模板, 电沉积制备了Ni-Mo合金纳米线. 用扫描电镜（SEM）和表面能谱（XPS）表征沉积物形貌和组成, 用伏安法研究了Ni-Mo合金纳米线的沉积条件及催化性能. 结果表明, Ni-Mo合金纳米线的直径在20～30 nm之间. Ni-Mo共沉积的伏安图上在-1.4 V（vs Ag/AgCl）左右出现一个扩散电流平台. 光电子能谱（XPS）表明, Ni-Mo合金纳米线的共沉积电位出现在-1.4 V以后, 大于这个电位钼以低价氧化物存在. Mo-Ni离子浓度比大于2时扩散电流平台消失. 柠檬酸盐浓度达到2～3倍镍盐浓度时, 扩散电流平台趋于稳定. 在较优条件下电沉积的Ni-Mo合金纳米线显示较高的析氢催化活性.

Ni-Mo alloy nanowires were prepared using porous anodic alumina （PAA） as templates and were characterized by SEM and XPS. Voltammetry was performed in order to determine the optimum conditions for codeposition of Ni-Mo alloy nanowires. SEM micrographs revealed that the diameter of the Ni-Mo alloy nanowires was about 20 - 30 nm. Vohammogram of the Ni-Mo alloy codeposition presented an obvious plateau of a limiting current. XPS indicated that the complete reduction of Mo ion occurred at potentials more negative than - 1.4 V, corresponding to the beginning of the plateau of the limiting current. When the concentration ratio of molybdate salt to nickel salt was higher than 2, the plateau of the limiting current disappeared. When the concentration of citrate salt was 2 3 times higher than that of nickel salt, the plateau of the limiting current tended to stability. The as-prepared Ni-Mo alloy nanowires exhibited a better catalytic activity for hydrogen evolution reaction.