Development of nanostructured supported photocatalysts for hydrogen production and inorganic pollutants removal

Semiconductor photocatalysis has emerged as one of the most promising approach to exploit a renewable energy source (i.e. sunlight irradiation) for several environmental purposes such as the production of clean energy (e.g. photocatalytic H2 evolution), the removal of organic and inorganic pollutants in natural water, purification of air and antibacterial activity. In view of these recent trends, the focus of this thesis was directed towards the study of different supported photo(electro)catalytic materials for topical environmental applications: i) Photocatalytic hydrogen gas evolution from aqueous solutions under UV light irradiation (365 nm) over highly ordered TiO2 nanotubes decorated through a sputtering/dewetting approach with a well-defined stacked co-catalyst (a WO3 layer decorated with Pt NPs); ii) Photocatalytic hydrogen gas evolution from aqueous solutions under UV light irradiation (365 nm) over highly ordered TiO2 nanotubes decorated through a sputtering/dewetting approach with dewetted-alloyed NiCu nanoparticles; iii) Photocatalytic reduction/scavenging of inorganic mercury (Hg(II)) from water under solar light irradiation over templated-dewetted Au on TiO2 nanotubes; iv) Photoelectrocatalytic oxidation/abatement of inorganic arsenic (As(III)) over hematite-based photoanodes under solar light irradiation. After a general introduction about photocatalytic processes and materials, each chapter of this dissertation contains the outcomes of the above listed studies.