Fast and real-time observation of hydrogen absorption kinetics for palladium nanoparticles

Matsumura, Daiju   ; Okajima, Yuka*; Nishihata, Yasuo; Mizuki, Junichiro

Dynamical structural change of Pd nanoparticles during hydrogen absorption was directly observed by X-ray absorption fine structure with dispersive optics. Hydrogen pressure dependence of the expansion of the interatomic distance in Pd nanoparticles was estimated by real-time-resolved observation with a rate of 50 Hz. It has been revealed that the Pd nanoparticles show strong hydrogen pressure dependence of the reaction rate. Determined reaction order implies that the surface dissociative adsorption process is the key issue for the hydrogen storage kinetics.