To investigate the radiation damage as well as the doping effect of ion implantation, oxide-covered titanium electrodes were implanted with various concentration profiles of palladium ions (Pd +). The comparison of the electrochemical data allows separation of the influences of doping and Frenkel defects. Measurements of repassivation, capacity and photocurrent show a dominant influence of defect production increasing in the following order of the profiles: out < in < tot < through. For repassivation up to 2 V, defects with a high mobility migrate out of the film and form new oxide of up to 0.2 nm thickness. In capacity measurements, donor production of up to 4 × 10 19 cm −3 can be detected, but less than 40% of the donors can be eliminated during repassivation. The photocurrent spectrum shows amorphization of the oxide, a decrease in the mobility gap and the production of localized electronic states in the mobility gap. The rate of electron transfer reactions increases in the order out < in ≈ through < tot by several orders of magnitude. This shows that the production of defects enhances electron transfer reactions but that doping with palladium ions is most effective. For the out profiles, the unchanged inner layer represents an additional barrier for anodic electron transfer. When the data for the various profiles are compared and summarized, various defects with different concentrations, energies and mobilities can be distinguished, and the potential distributions can be estimated for the various profiles.