SHORT COMMUNICATION - HYDROGEN DIFFUSION STUDIES OF MICROCRYSTALLINE LANI3.94SI0.54 FILMS USING THE ELECTROCHEMICAL PERMEATION TECHNIQUE

Microcrystalline LaNi3.94Si0.54 films were prepared by ion beam sputte ring on steel substrates to gain bilayer composite specimens. Hydrogen diffusion studies of microcrystalline LaNi3.94Si0.54 films were condu cted using the electrochemical permeation technique. Hydrogen diffusio n transient curves were found to be composed of two steps of transient s, which might be ascribed to the transition from alpha phase to hydri de phase and the following migration of the phase boundary. The hydrog en diffusion coefficients in the alpha phase of the alloy film were al so calculated from the hydrogen diffusion transient curves. Similarly to an earlier suggestion, the electrochemical permeation technique is useful in the investigation of hydride formation in hydrogen storage a lloy in addition to providing hydrogen diffusion coefficients in the a lpha phase of the alloy.