Development of a TiO2 nanotube array-based photo-reactor for H2 production by water splitting

We report on the development of an innovative photoelectrochemical (PEC) cell based on the use of Ti02 nano-engineered array thin films as photo-anode for water splitting and/or ethanol photoreforming processes. The photo-reactor was realized in a highly compact configuration in order to reduce light scattering phenomena due to the water and maximize the photocatalytic efficiency. The separation of the photo-induced process in two physically distinct areas related to water oxidation (to form O2, protons and electrons) and proton reduction (to form H2) allowed to overcome some drawbacks of the reaction, by limiting charge recombination and avoiding the fast back-reaction to water. Results in terms of hydrogen production showed Pt-doped Ti02 nanotubes to be the best photocatalysts used, where their performance depended upon the parameters chosen during the preparation of the samples.