Hydrogen getters have been used in U.S. Department of Energy components for over 20 years. Current getter systems use an acetylenic organic material with a carbon-supported metal catalyst (1,4-bis [phenylethynyl] benzene [DEB] and palladium/carbon). Traditional preparation of this getter is done by mixing the DEB with palladium and carbon in a ball mill process followed by pressing, remilling, and pelletizing before final assembly into perforated getter support tubes. The tubes are placed in the components in a location somewhat remote from potential sources of hydrogen. A new chemical vapor deposition (CVD) and physical vapor deposition (PVD) codeposition process has been developed for fabricating the palladium-catalyzed DEB getter. The process involves the codeposition of the DEB/Pd/carbon onto planar and complex surfaces and infiltration into porous substrates using modern CVD and PVD techniques. DEB was sublimed from solid DEB. Palladium and carbon were produced through the UV photolysis (254 nm) of allylcyclopentadienylpalladium, which was synthesized for this project. The DEB and the palladium/carbon precursor are admitted simultaneously to the reaction chamber via bubbler reservoirs. The codeposition processing is simple, low-temperature, scalable, and lends itself well to placing the getter onto complex shapes and substrates of various compositions. The new getter deposition technique offers the potential advantages of high surface area, ease of component surveillance and remanufacture, and intimate contact with source materials evolving hydrogen and those most sensitive to attack by hydrogen. Hydrogen uptake on getter produced by the new codeposition technique has been demonstrated.
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