Article ID | Journal | Published Year | Pages | File Type |
---|---|---|---|---|
5361832 | Applied Surface Science | 2011 | 10 Pages |
Dense PdAgCu ternary alloy composite membranes were synthesized by the sequential electroless plating of Pd, Ag and Cu on top of both disk and tubular porous stainless steel substrates. X-ray diffraction and scanning electron microscopy were employed to study the structure and morphology of the tested samples. The hydrogen permeation performance of these membranes was investigated over a 350-450 °C temperature range and a trans-membrane pressure up to 100 kPa. After annealing at 500 °C in hydrogen stream followed by permeation experiments, the alloy layer presented a FCC crystalline phase with a bulk concentration of 68% Pd, 7% Ag and 25% Cu as revealed by EDS. The PdAgCu tubular membrane was found to be stable during more than 300 h on hydrogen stream. The permeabilities of the PdAgCu ternary alloy samples were higher than the permeabilities of the PdCu alloy membranes with a FCC phase. The co-segregation of silver and copper to the membrane surface was observed after hydrogen permeation experiments at high temperature as determined by XPS.
⺠PdAgCu membranes were prepared by sequential electroless plating technique. ⺠Hydrogen permeabilities of PdAgCuFCC alloy were higher than permeabilities of PdCuFCC membranes. ⺠Both XRD and XPS provided evidence of the PdAgCuFCC ternary alloy formation. ⺠Ag and Cu co-segregation to the surface takes place under hydrogen permeation experiments.