Deposition of Pd–Ag thin film membranes on ceramic supports for hydrogen purification/separation

Journal Article · Thu Jan 15 00:00:00 EST 2015 · Materials Research Bulletin

DOI:https://doi.org/10.1016/J.MATERRESBULL.2014.10.055· OSTI ID:22420788

Pereira, A. I. ^[1]; Pérez, P.; Rodrigues, S. C.; Mendes, A.; Madeira, L. M. ^[2]

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1. Centre of Physics, University of Minho, Campus Azurém, 4800-058 (Portugal)
2. LEPAE, Chemical Engineering Department, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias s/n, 4200-465 Porto (Portugal)

Highlights: • Thin film Pd–Ag membranes have been produced for hydrogen selectivity. • Magnetron sputtering yields Pd–Ag compact films for atomic H diffusion. • The thin film Pd–Ag membranes yielded a selectivity of α (H{sub 2}/N{sub 2}) = 10. - Abstract: Pd–Ag based membranes supported on porous α-Al{sub 2}O{sub 3} (doped with yttria-stabilized zirconia) were studied for hydrogen selective separation. Magnetron sputtering technique was employed for the synthesis of thin film membranes. The hydrogen permeation flux is affected by the membrane columnar structure, which is formed during deposition. From scanning electron microscopy analysis, it was observed that different sputtering deposition pressures lead to distinct columnar structure growth. X-ray diffraction patterns provided evidence of a Pd–Ag solid solution with an average crystallite domain size of 21 nm, whose preferential growth can be altered by the deposition pressure. The gas-permeation results have shown that the Pd–Ag membrane supported on porous α-Al{sub 2}O{sub 3} is selective toward H{sub 2}. For optimized membrane synthesis conditions, the permeance toward N{sub 2} is 0.076 × 10{sup −6} mol m{sup −2} s{sup −1} Pa{sup −1} at room temperature, whereas for a pressure difference of 300 kPa the H{sub 2}-flux is of the order of ca. 0.21 mol m{sup −2} s{sup −1}, which corresponds to a permeance of 0.71 × 10{sup −6} mol m{sup −2} s{sup −1} Pa{sup −1}, yielding a selectivity of α (H{sub 2}/N{sub 2}) = 10. These findings suggest that the membrane has a reasonable capacity to selectively permeate this gas.

• OSTI ID: 22420788
• Journal Information: Materials Research Bulletin, Vol. 61; Other Information: Copyright (c) 2014 Elsevier Science B.V., Amsterdam, The Netherlands, All rights reserved.; Country of input: International Atomic Energy Agency (IAEA); ISSN 0025-5408
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
ALUMINIUM OXIDES
CERAMICS
DIFFUSION
DOPED MATERIALS
HYDROGEN
MEMBRANES
PALLADIUM
POROUS MATERIALS
SCANNING ELECTRON MICROSCOPY
SILVER
SOL-GEL PROCESS
SOLID SOLUTIONS
SURFACE PROPERTIES
SYNTHESIS
TEMPERATURE RANGE 0273-0400 K
THIN FILMS
X-RAY DIFFRACTION
YTTRIUM OXIDES
ZIRCONIUM OXIDES