Abstract
The homogeneity of typical electrolessly plated Pd/Ag membranes for H2
separation was investigated with XAFS and XPS depth profiling. Next the crucial
mixing of the separate Pd and Ag layers, obtained after the two sequential plating steps, was followed in situ with XRD. The results show that some low temperature alloying procedures found in the field are insufficient for obtaining a well-mixed Pd/Ag alloy membrane.
Finally the Pd/Ag-H XANES was determined for the first time. In contrast to
the Pd-H and Pd/Ag systems, shifts in electron density from the Ag or H atoms
to the Pd could not satisfactorily explain the observed XANES. Not only is the
intensity of the whiteline higher than expected, the shape and the intensity of the
anti-bonding Pd 4d H 1s feature have also significantly changed. Local geometry
is expected to account for these deviations.
separation was investigated with XAFS and XPS depth profiling. Next the crucial
mixing of the separate Pd and Ag layers, obtained after the two sequential plating steps, was followed in situ with XRD. The results show that some low temperature alloying procedures found in the field are insufficient for obtaining a well-mixed Pd/Ag alloy membrane.
Finally the Pd/Ag-H XANES was determined for the first time. In contrast to
the Pd-H and Pd/Ag systems, shifts in electron density from the Ag or H atoms
to the Pd could not satisfactorily explain the observed XANES. Not only is the
intensity of the whiteline higher than expected, the shape and the intensity of the
anti-bonding Pd 4d H 1s feature have also significantly changed. Local geometry
is expected to account for these deviations.
Original language | English |
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Pages (from-to) | 278-280 |
Number of pages | 3 |
Journal | Physica Scripta |
Volume | T115 |
DOIs | |
Publication status | Published - 2005 |