Direct measurement of hydrogen diffusivity through Pd-coated Ni-based amorphous metallic membranes

A time-lag technique was employed to evaluate the chemical diffusivity and permeability of hydrogen through amorphous metallic alloys. As a reference, similar measurements were taken on pure palladium. While hydrogen diffusivity for the amorphous structures was smaller than that for a palladium membrane, the amorphous membranes exhibited higher hydrogen solubility, resulting in comparable hydrogen permeability. An increase in zirconium content increased permeability by enhancing hydrogen diffusivity, although the amount of hydrogen contributing to the hydrogen flux was not affected.