Martin Setvin(Institute of Applied Physics, TU Vienna, Vienna, Austria)
TiO2 is a prototypical metal oxide used in photocatalysis [1], photoelectrochemical (Grätzel) solar cells [2], and transparent conducting oxides [3]. Industrially two forms of TiO2 are used, rutile and anatase. The behavior of charge carriers is of key importance in virtually all applications of these materials.