ETR ON TIO2 FILMS MODIFIED BY PT DOPING

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.