Deposition of Pd-Cu thin films on V-15Ni membrane and their hydrogen permeation

Pd-Cu/V-15Ni composite membranes were deposited for the first time by co-sputtering in this paper. XRD, SEM and AES were performed to characterize the composite membrane. Cu concentration of the Pd-Cu overlayer shows a linear dependence on the Cu target sputtering voltage (V-Cu) when Pd target voltage is constant and V-Cu > 300V. SEM observation shows that the overlayer films have very dense and fine microstructure; XRD and AES analysis reveal that the films are well alloyed and have homogeneous composition distribution. The depositing rate is about 3.4 nm/s when the Pd and Cu target voltages are set as 340V and 395V respectively. The obtained Pd60Cu40/V-15Ni composite membrane shows higher hydrogen permeability than that of Pd60Cu40 alloy membrane and presents good feasibility to replace the Pd60Cu40 alloy membrane for hydrogen purification in the temperature range of 423-673K.