Hydrogen Permeation through fcc Pd–Au Alloy Membranes

Abstract

H permeabilities have been measured for a series of fcc Pd–Au alloy membranes in the temperature range from 393 to 573 K. The maximum permeability is found at the atom fraction of Au, XAu = 0.11 ± 0.01, which closely agrees with a theoretically predicted value (Sonwane, C.; Wilcox, J.; Ma, Y. J. Chem. Phys.2006, 125, 184714). For a series of Pd–Au alloy membranes with different Au contents, diffusion constants, activation energies, and pre-exponential factors have been determined as a function of H content. H concentration-independent values of these parameters have been obtained by extrapolation to H→0 where the H solution behaves ideally.