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

The effect of ion irradiation on the rate of electrochemical hydrogen absorption 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 for ion doses up to 1×1017 cm−2. As the ion dose increased, the initial rate of hydrogen absorption of Pd was increased. The ion irradiation treatment of the surface of a metal induces high concentrations of vacancies. The increased rate of hydrogen absorption may be caused by the introduction of a high concentration of vacancies which traps hydrogen atoms. The ion irradiation was found as an effective way to enhance the rate of the initial activation of the electrochemical hydrogen absorption of Pd.