Efficient H 2 production by photocatalytic water splitting under UV or solar light over variously modified TiO 2 -based catalysts

This paper focused for the first time on the comparison between three different approach to modify the chemico-physical properties of TiO 2 -based photocatalysts and their effect in the H 2 production by photocatalytic water splitting both under UV and solar light irradiation, under the same experimental conditions. The application of pulsed laser irradiation to aqueous TiO 2 suspensions (first approach) induced structural transformations both on the bulk and on the surface of TiO 2 , boosting the H 2 production, under UV light irradiation, of almost three times (20.9 mmol/g cat ·h) compared to bare TiO 2 (7.7 mmol/g cat ·h). The second strategy was based on a templating method to obtain TiO 2 with a macroporous structure to favour an efficient light absorption process inside the material pores, thus allowing a high H 2 production (0.64 mmol/g cat ·h) under solar light irradiation. This performance was further enhanced when the macroporous TiO 2 was coupled with CeO 2 or W (third approach). In the latter case the H 2 production increased to 0.72 mmol/g cat ·h for macroporous TiO 2 [sbnd]CeO 2 and to 0.82 mmol/g cat ·h for macroporous TiO 2 [sbnd]W. This work highlights how it is possible to tune the TiO 2 photocatalytic properties with easy and green procedures to obtain environmental friendly catalyst for hydrogen production.