This Special Issue welcomes both review and original research articles on all aspects of heterogeneous and homogeneous photocatalysis with an emphasis on fundamental and applied research on photocatalytic reactions. Photocatalysis based on semiconducting photoactive materials has grown tremendously in the last two decades. Photocatalyis by semiconductors photocatalysts could convert water into oxygen and hydrogen or organics to CO2 and water. Excitation by UV/Visible lights generate electron–hole pairs that could reach the surface of the semiconductor nanoparticles resulting in chemical oxidation or reduction reactions. Several materials have been produced, characterized and tested. The main aim is to produce photocatalysts with absorption in the visible range and systems that reduce electron–hole recombination. The rational design of new classes of photocatalytic materials requires a deep understanding of the basic physical principles of photocatalysis. The present special issue provides a survey of some of the most interesting techniques and methodological advances in the characterization of the basic processes of photocatalysis.

Aims and Scope:

1. Treatment and disinfection of water and wastewater
2. treatment air pollutants using photocatalytic techniques;
3. Photochemistry and photocatalysis;
4. advanced materials for photochemical and photocatalytic applications
5. New perspectives in environmental photochatalysis
6. Semi-pilot and pilot solar photocatalytic systems;
7. Process fundamentals and principles;
8. Photocatalytic hybrid systems;
9. H2 production and CO2 reduction using Photocatalytic systems