Palladium-copper alloy films

This conclusion was additionally confirmed by Palczewska and Janko (67) in separate experiments, where under the same conditions nickel-copper alloy films rich in nickel (and nickel films as well) were transformed into their respective hydride phases, which were proved by X-ray diffraction. The additional argument in favor of the transformation of the metal film into hydride in the side-arm of the Smith-Linnett apparatus consists of the observed increase of the roughness factor ( 70%) of the film and the decrease of its crystallite size ( 30%) after coming back from low to high temperatures for desorbing hydrogen. The effect is quite similar to that observed by Scholten and Konvalinka (9) for their palladium catalyst samples undergoing the (a — j8) -phase transformation. 

In the first experiments, palladium copper alloy was deposited by magnetron sputtering from a target with the composition Pd 60%/Cu 40% (by weight) in an argon plasma, on to flexible film of polyvinyl alcohol (PVA, trade name Solublon ) and on to polystyrene. The alloy films were from 0.5 to 3 microns thick and had a minimal intrinsic stress. This was evident from the fact that the films had no tendency to curl up. 

Complex substrate modifications involving intermediate layers and palladium alloy deposition methods are often required for superior membrane performance. Modification of a membrane support surface before palladium deposition by sintering on smaller particles can create a smoother surface with smaller pores, facilitating the deposition of a defect-free palladium layer. Nickel microparticles have been sintered together to form a porous support that was sputter-coated with palladium and then copper [118]. Thermal treatment at 700 °C for 1 h promoted reflow to create a durable, pinhole-free membrane with a Pd-Cu-Ni alloy film. In another case, starting with commercially available PSS with a 0.5 pm particle filtration cut-ofF, submicron nickel particles were dispersed on the surface, vacnium sintered for 5 h at 800 °C, and then sputtered with UN [159]. The nickel particles created a smoother surface with smaller pores, so a thinner palladium alloy layer... 

Electrical connectors - [ELECTRICALCONNECTORS] (Vol 9) -palladium films as [PLATINUM-GROUP METALS, COMPOUNDS] (Vol 19) -polycarbonates for [POLYCARBONATES] (Vol 19) -use of copper [COPPER] (Vol 7) -use of tellurium alloys [TELLURIUM AND TELLURIUM COMPOUNDS] (Vol 23) -use of wrought copper alloys [COPPER ALLOYS - WROUGHT COPPER AND WROUGHT COPPER ALLOYS] (Vol 7) -use of wrought copper alloys [COPPER ALLOYS - WROUGHT COPPER AND WROUGHT COPPER ALLOYS] (Vol 7)... 

Another important problem is the elimination of the chemical interactions between contacting phases and also of the diffusion of metal atoms into the oxide bulk [487 89], One example is the operation of commonly used indium junctions, which are convenient because films of this soft metal and its alloys can be applied mechanically [490], This fact stimulates the quest for low-temperature techniques for junction fabrication. It is known that silver, gold, and copper, and also probably platinum [202] and palladium [487], are most suitable because of their weak interaction with HTSCs. 

The alloy catalysts used in these early studies were low surface area materials, commonly metal powders or films. The surface areas, for example, were two orders of magnitude lower than that of platinum in a commercial reforming catalyst. Hence these alloys were not of interest as practical catalysts. The systems emphasized in these studies were combinations of metallic elements that formed continuous series of solid solutions, such as nickel-copper and palladium-gold. The use of such systems presumably made it possible to vary the electronic structure of a metal crystal in a known and convenient manner, and thereby to determine its influence on catalytic activity. Bimetallic combinations of elements exhibiting limited miscibility in the bulk were not of interest. Aspects of bimetallic catalysts other than questions related to the influence of bulk electronic structure received little attention in these studies. 

Athayde et al. [13] in the sputtering of Pd-Ag alloys their films were also palladium-rich relative to the sputtering target. This is something that can be adjusted by addition of copper to the target. 

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