3. Other photocatalytic materials

Interest in photocatalytic materials active under irradiation in the visible range continues to grow, and current research is focused on the development of new semiconductors. Such a semiconductor must meet certain criteria that can be deduced from the photocatalytic mechanism described above:

• to absorb in the visible (λ = 400 - 800 nm), the energy value E _g of its band gap must be between 1.6 and 3.1 eV ;

• the position of the valence (E _BV ) and conduction (E _BC ) bands should enable reduction or oxidation reactions to take place in a large number of molecules; the feasibility of redox half-reactions will depend on the values of E _BC and E...