Synthesis and gas-transmission parameters of Pd-Ag membranes with modified surface

Methods to modify the surface of Pd-23% Ag alloy films were developed in order to increase the velocity of hydrogen transmission; we obtained palladium coating of "nanoparticles" and "nanopores" type. Modification of Pd-Ag films surface, obtained by nanoporous palladium coating with a predominant distribution of particles from 0 to 50 nm, makes it possible to achieve a hydrogen flow density of 0.48 mmol / (s*m2), which is 1.4 times greater in comparison with modification by "nanoparticles" coating under low temperature (<90 ° C) and pressure (<0.6 MPa) conditions. Experimental evidence is obtained that velocity of hydrogen transmission, under the given conditions, is limited by dissociative-associative processes at the boundaries, and it can be significantly increased (up to order of magnitude) due to acceleration of the limiting stage of process with the help of palladium nanostructured coating formation on the surface. (paper)