Pd–Cu alloy membranes were prepared on porous Al2O3 substrate by electroless plating of Pd, electroplating of Cu and alloying, successively. Scanning electron microscopy (SEM), X-ray diffraction (XRD), metallographic microscopy and hydrogen permeation kinetics were applied in membrane characterization. The effects of the operation temperature and the membrane composition on the hydrogen permeability, the pressure exponent n as well as the H2 permeation activation energy of the membranes were investigated. The Cu/Pd/Al2O3 precursors can be completely alloyed when annealed at 500℃ in hydrogen for 20 h. The Pd61Cu39 membrane exhibits the highest hydrogen permeability among all of the studied membranes. With the decreasing temperature, the hydrogen permeability of the Pd45Cu55, Pd51Cu49 and Pd69Cu31 membranes decreases, while that of the Pd61Cu39 and Pd63Cu37 membranes decreases at first, then increases and finally decreases. With the decrease in temperature from 600 to 350℃, the n value of the Pd45Cu55, Pd51Cu49 and Pd69Cu31 membranes tends to increase, while that of the Pd61Cu39 and Pd63Cu37 membranes changes complicatedly. Within the testing temperature, the apparent activation energies for H2 permeation through the Pd45Cu55, Pd51Cu49 and Pd69Cu31 membranes are 32.9, 24.1, 21.8 kJ·mol–1, respectively, while those for the Pd61Cu39 and Pd63Cu37 membranes are unstable. XRD results show that at room temperature the crystalline structure of the metal layers of the Pd59Cu41, Pd61Cu39 and Pd63Cu37 membranes are bcc phase, while that of the Pd45Cu55, Pd51Cu49, Pd69Cu31 and Pd81Cu19 membranes are fcc phase.% 以多孔 Al2O3为基体，先化学镀钯然后再电镀铜，最后进行合金化处理制备了一系列钯铜合金膜。通过 SEM、XRD、金相显微镜以及透氢动力学分析等手段考察了膜的性能，并分析了测试温度和合金组成对膜的透氢率、压力指数 n 值及透氢活化能的影响。前驱体(Cu/Pd/Al2O3膜)在500℃、氢气气氛中经20 h 可完全合金化。在所制备的 Pd–Cu合金膜中，Pd61Cu39膜的透氢性能最佳。在350~600°C，Pd45Cu55、Pd51Cu49和 Pd69Cu31膜的氢通量随温度的降低而减小；Pd61Cu39和 Pd63Cu37膜的氢通量随温度的降低是先减小后增大，最后又减小。随温度的降低，Pd45Cu55、Pd51Cu49和 Pd69Cu31膜的渗透系数n值有增大的趋势；Pd61Cu39和 Pd63Cu37膜的 n 值变化较为复杂。在所测温度范围，Pd45Cu55、Pd51Cu49、Pd69Cu31膜的透氢活化能分别为32.9、24.1、21.8 kJ×mol-1，而 Pd61Cu39和 Pd63Cu37膜则不存在固定的透氢活化能。XRD 测试显示：室温下 Pd59Cu41、Pd61Cu39和 Pd63Cu37膜的晶体结构为bcc 型；Pd45Cu55、Pd51Cu49、Pd69Cu31和 Pd81Cu19膜的晶体结构为 fcc 型。
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