ETR at Ti/TiO2-Pt electrodes under different conditions were investiga
ted and a correlation with the electronic properties of the films was
made. The effect of doping concentration, film thickness and temperatu
re was analysed. An increase of the catalytic properties of the films
was observed for increasing Pt concentration. A diminution of the elec
tron transfer current with the film thickness was obtained. The presen
ce of Pt within the film also produces a decrease of the energy of act
ivation, mainly in the cathodic direction, where it remains almost con
stant with the potential. The results are interpreted in terms of a di
rect resonance tunnelling between the redox couple and the underlying
metal.