Photocatalytic processes in spatially confined micro- and nanoreactors

In this review recent progress in photocatalysis on mesostructured systems, which behave as spatially confined micro- and nanoreactors, is presented. Mesoporous oxides and hybrid photocatalysts based on molecular-organized assemblies offer new possibilities of concentrating low reactant levels, controlling the reaction environment, separating photocatalyst and reaction products, and realizing host-guest catalysis of light-driven reactions. This allows one to organize the catalytic photolysis in an especially efficient way, to increase its selectivity, and to ensure another set of products as compared to photocatalysis in suspension of dispersed photocatalyst. Further increase in selectivity can be attained through functionalization of spatially confined photoreactors to impart them bio- or chemical recognition properties, to couple different photo- and redox-catalysts, and to create complicated hybrid microphotoreactors including those which mimic the natural photosynthetic centers.