Photo-catalysis: water or air depollution and self-cleaning materials

Photocatalysis is an emerging advanced oxidation technology with many areas of application, particularly in Japan. Most of them use materials based on titanium dioxide (TiO ₂ ). In this article we present only the environmental applications of these materials for air or water purification or self-cleaning applications. Applications in the field of energy by systems capable of storing solar energy, such as solar cells (dye-sensitized photovoltaic cells for electricity generation or DSSC [D 3935] [BE 8579] [BE 8578 ]) and hydrogen production by photocatalytic water splitting (fuel cells [BE 8565] ), will not be discussed, nor will the photo- or electrochromic or sensor properties [P 4031] [R 2385] .

The principle of photocatalysis is based on the activation of a semiconductor by light, and the energy and thermodynamic data governing photo-induced oxidation-reduction reactions are explained. The properties of various semiconductors capable of inducing photocatalytic reactions are discussed, before those of titanium dioxide are described in...