Cu–TiO2 systems for the photocatalytic H2 production: Influence of structural and surface support features.

The influence of different TiO 2 supports on the Cu active species has been studied. It was found that the photocatalytic H 2 evolution is highly affected by the structural and electronic features of surface Cu species. Thus, metal dispersion and oxidation state appears strongly conditioned by the structural and surface properties of the TiO 2 support. We have examined three TiO 2 supports prepared by different synthetic methods; sol–gel, hydrothermal and microemulsion. In addition, we have induced structural and surface modifications by sulfate pretreatment over freshly prepared TiO 2 precursors and subsequent calcination. Notably different copper dispersion and oxidation state is obtained by using these different TiO 2 supports. From the wide structural and surface analysis of the catalysts we are able to propose that the occurrence of highly disperse Cu 2+ species, the sample surface area as well as the crystallinity of the TiO 2 support are directly related to the photocatalytic activity for H 2 production reaction. [ABSTRACT FROM AUTHOR]