Preparation of Pd-Ag alloy membranes

Alloying Pd with Ag to form Pd-Ag alloy Hj permeation membrane can not only improve the embrittlement but also improve the H2 permeability. Simultaneously, less use of Pd greatly decreases the membrane cost. Therefore, the Pd-Ag membranes were extensively studied for preparation and applications. The techniques used for the pure Pd membrane preparation were also tried for Pd-Ag alloy membrane preparation. As mentioned before, the preparation of Pd-Ag membranes also focused on the supported composite Pd-Ag configuration. 

21 XRD patterns (111-face) of Pd-Ag alloys with different compositions (Tong etal., 2006b). 

Electron probe microanalysis indicated that the Pd-Ag alloy composite membranes had a stable structure and a homogeneous Pd-Ag alloy layer. In addition, the membrane reactor for methane SR was constructed and the reaction performance was tested. The methane conversion, which was as high as 80%, was achieved at a lower temperature of 500°C and a pressure of 500 kPa. 

3 Radio frequency (RF) magnetron sputtering deposition technique 

Electroless plating was used by Shu et al. (1993) to deposit simultaneously Pd-Ag membrane on porous stainless steel substrate. This work investigated the co-deposition behaviour of Pd and Ag on porous stainless steel by means of electroless plating. Although Pd and Ag can be deposited independently to a considerable thickness, simultaneous deposition of palladium and silver was passivated by the preferential deposition of Ag in an electroless bath containing EDTA as a complexing agent. After effective 

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