Hydrogen permeation through copper-coated palladium

Journal Article · Tue Oct 01 00:00:00 EDT 1991 · Journal of Applied Physics; (United States)

DOI:https://doi.org/10.1063/1.349256· OSTI ID:5208427

Andrew, P L; Haasz, A A ^[1]

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1. University of Toronto, Institute for Aerospace Studies, 4925 Dufferin Street, North York, Ontario (Canada)

The rate of hydrogen uptake and release by metals can be strongly affected by surface barriers for adsorption and desorption. The rate of hydrogen permeation through a Pd membrane was measured for both incident molecules (10{sup {minus}3}--10{sup {minus}4} Pa) and neutral atoms (10{sup 16}--10{sup 19} H{sup 0}/m{sup 2}{center dot} s) for membrane temperatures of 300--570 K. The pressure dependence of H{sub 2}-driven permeation was used to identify regimes where the permeation was controlled by bulk processes (diffusion-limited) and surface processes (surface-limited). The dependence of the H{sup 0}-driven permeation rate on the direction of permeation was used to separate the contribution of each surface to the overall surface-limited permeation rate. One of the membrane surfaces was coated {ital in} {ital situ} with copper evaporated from a hot source. This same surface could be monitored {ital in} {ital situ} by Auger electron spectroscopy. At temperatures below 450 K, stable copper coatings were made with thicknesses ranging from {similar to}3 to 25 nm. The thin Cu coatings led to a decrease in the H{sub 2}-driven permeation rate. The permeation rate was found to increase, however, for H{sup 0} atoms incident on the Cu-coated surface. This is consistent with a barrier for H{sub 2} dissociation and H recombination at the Cu/vacuum interface. Membranes with such a barrier, in conjunction with a source of H{sup 0} atoms, have applications as hydrogen pumps.

• OSTI ID: 5208427
• Journal Information: Journal of Applied Physics; (United States), Vol. 70:7; ISSN 0021-8979
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
75 CONDENSED MATTER PHYSICS
SUPERCONDUCTIVITY AND SUPERFLUIDITY
08 HYDROGEN
HYDROGEN
DIFFUSION
PALLADIUM
MEMBRANE TRANSPORT
COPPER
HIGH TEMPERATURE
MEDIUM TEMPERATURE
PRESSURE DEPENDENCE
SURFACE COATING
SURFACE POTENTIAL
DEPOSITION
ELEMENTS
METALS
NONMETALS
PLATINUM METALS
POTENTIALS
TRANSITION ELEMENTS
360100* - Metals & Alloys
656003 - Condensed Matter Physics- Interactions between Beams & Condensed Matter- (1987-)
080800 - Hydrogen- Properties & Composition