Photoelectrochemistry has been intensively studied in the field of hydrogen production from water and solar energy. The photoelectrochemical splitting of water was historically discovered by Fujishima and Honda in 1972 onto TiO electrodes. Recently many materials have shown promising properties to split efficiently water but TiO remains cheap, abundant, stable against photo-corrosion. The main problem of TiO is its bandgap which is 3 or 3.2 eV according to its crystallinity (anatase or rutile). These values are too high and only the wavelength in the UV region can be absorbed. To increase the performances of this material to split water with solar wavelength, it is necessary to sensitize the TiO. Currently Quantum Dots sensitization is very promising but more research is needed to find new materials able to absorb the light efficiently.