Shifting towards cleaner sources of energy needs great efforts to overcome the environmental problems of our modern society. Solar fuel and the use of solar energy for photocatalytic hydrogen production seem to be rather promising alternatives. Unfortunately, the lack of high efficient solar harvesting materials is the main obstacle towards the practical application. Titanium dioxide is considered to be one of the most widely used photocatalytic material despite the fact that it is only absorbs the UV light, hence its modification is requred in order to benefit of a wider range of solar spectrum.

Several self-prepared TiO₂ photocatalyst has been synthesized via evaporation-induced self-assembly (EISA) method before its modification by precious metals using alloying and photodeposition methods. Au/TiO₂ composite has been prepared by alloying method and its photocatalytic activity was compared with other composites prepared by Au loading on the surface of TiO₂. Furthermore, photodeposition method has been used also to prepare Pt/TiO₂ and Au-Pt/TiO₂ composites.

All the self-prepared TiO₂ photocatalysts and their composites with precious metals have been characterized by different techniques (XRD, DRS, TEM, and BET), and their flat-band potentials were determined using Mott-Schottky measurements.

It was found that in the presence of ethanol as a sacrificial agent and under solar light irradiation, the unmodified TiO₂ photocatalyst achieved a maximum H₂ evolution rate of 0.4 mmol.g^-1.h^-1 which was about 4 times higher than the evolution rate using P25 and UV100. Furthermore, the modification with gold enhanced the solar evolution of H₂ and the results clearly showed that the photocatalytic activity of the employed photocatalysts seems to be dependent on the modification method, where a value of 5 and of 10.5 mmol.g^-1.h^-1 of H₂ have been recorded. Moreover, loading Pt on the surface of TiO₂ had a significant positive impact on the photocatalytic hydrogen evolution and their composites exhibited higher photocatalytic activity compared with that of Au/TiO₂ composite. However, the presence of both Au and Pt nanoparticles did not have the expected high impact in raising the efficiency in solar light.

Finally, the impact of the modification of TiO₂ by precious metals on the photoelectrochemical behavior was studied. A comparison of PEC catalytic activities was performed by linear sweep voltammetric scans, in dark and light, of several photoanodes prepared of the self-prepared composites. Also, the correlation between PEC measurements and the photocatalytic activity will be discussed.