Effects of ion beam modification on absorption and transport of hydrogen in perovskite-type oxide ceramics

Surface modification of proton conductive material (Yb-doped SrCeO ₃ perovskite-type ceramics) has been carried out by irradiation with 10 keV D2+, He⁺ or Ar⁺ ions at room temperature. By exposure of Ar gas including H₂O to the irradiated surface, the concentration of H in the projected range increased. The absorption of H is associated due to dissociation of H₂O. The concentrations of the absorbed H by D⁺, He⁺ and Ar⁺ ion irradiations became about 2.0, 0.3 and 1.0 times, respectively, as much as the saturation concentration by H⁺ ion implantation. It was also found by isochronal annealing experiments that the thermal desorption rate of H retained in the irradiated surface was lower than that in the unirradiated one. These results show that the trapping and migration of hydrogen atoms in the proton conducting oxide ceramics are enhanced by ion beam modification.