24-10-2012, 11:30 AM
Cost-Effective Method for Producing Self Supported Palladium Alloy Membranes for Use in Efficient Production of Coal Derived Hydrogen
ABSTRACT
Competed fabrication of an initial series of copper and palladium-copper alloy membranes in the range of 1-8 microns
in thickness up to 6 inches x 8 inches in area. Films were produced using both e-beam evaporation (with and without ion assist)
and magnetron sputtering from a 60%Pd/40%Cu alloy target. Pure copper and palladium-copper alloy films, with essential no
intrinsic stress, were produced on both polystyrene and polyvinyl alcohol substrates. Various processing parameters and
techniques were investigated in order to minimize defects and maximize uniformity in single layer films. Even though films
to date are visually defect free, we are able to observe sub-micron size defects using a backlighting technique; we are currently
investigating a number of methods to create a gas impermeable membrane. At present, the metal films are effectively removed
from the polymer backing material by merely immersing the film in an appropriate solvent; chloroform for the polystyrene
and water for the PVA. In the future we plan to investigate alternative methods for removing the polymer backing that are more
suited to large scale, low-cost manufacturing.