Determination of Chemical Diffusion Coefficients in Metal Hydride Particles with a Microelectrode Technique

Microelectrochemical studies for hydrogen storage materials have been carried out by using a microelectrode technique. A carbon fiber filament was contacted with single particles of , and in 1 M KOH solutions by using a micromanipulator, where Lm indicates the lanthanum‐rich rare‐earth metal. In this way, cyclic voltammetry and potential step experiments, together with the in situ x‐ray diffraction experiments, were conducted and the apparent hydrogen diffusion coefficients in solid phases were determined. The current responses recorded as a function of time were analyzed with a spherical diffusion model and the results are reported herein.