Effects of surface modification by ion irradiation on the electrochemical hydrogen absorption rate of Pd

Abe, Hiroshi; Morimoto, Ryo*; Sato, Fumiatsu*; Azuma, Yorito*; Uchida, Hirohisa*

The effect of ion irradiation on the rate of electrochemical hydriding rate of palladium (Pd) was investigated. In this study, ion irradiation onto the Pd surface was made with H, He, Ar and N in the acceleration energy range from 30 to 350 keV, and in the ion dose up to 1 10 cm. As the ion dose was increased, the initial rate of hydriding of Pd was increased. The ion irradiatiion treatment of the surface of a metal induces high concentrations of vacancy. The increased hydriding rate may be caused by the induction of high concentration of vacancy whichi traps hydrogen atoms, and this seems to accelerate the rates of hydride nucleation and growth in the surface. The ion irradiation was found as an effective way to enhance the rate of the initial activation of Pd in the electrochemical hydriding process.