通过熔盐电解结合水溶液电沉积方法获得了复合型LaNi5/Ni—S合金镀层.Na3AlF6-La2O3(质量比为92:8)体系中的熔盐电解实验表明,由于阴极Ni具有较强的阴极去极化能力,即使在远未达到La析出电位的条件下,仍可获得LaNi5储氢合金层.电化学测试表明,该复合阴极材料具有较高的电化学活性,在80℃,30%NaOH溶液中,当阴极电流密度为150mA·cm^-2时,其析氢过电位仅为75mV.循环伏安及开路电位测试表明,LaNi5合金层在电解过程中可吸收一定量的氢,在电解槽出现断电或逆电流情况下这些吸收氢可发生放电过程,避免阴极材料溶出,从而为该析氢阴极提供电化学保护.
By molten salt electrolysis combined with aquatic electrodeposition, the composite LaNi5/Ni-S fihn with high stability and hydrogen evolution reaction activity was obtained, The results showed that in the Na3AlF6-La2O3 (mass ratio of 92 : 8) molten salt system, although the cathodic potential is much lower than the decomposition potential of lanthanum, the LaNi5 film could be obtained due to the strong depolarization ability of Ni cathode. The composite LaNis/Ni-S film (η150=75 mV, 80℃) could absorb more H atoms, which would be oxidized and avoid the dissolution of the Ni-S film under the state of open-circuit effectively and prolong the lifetime of the cathode.