Sensitized luminescence of trivalent europium by three-dimensionally arranged anatase nanocrystals in mesostructured titania thin films

The well-ordered array of pores and walls made up of nanocrystallites in a mesoporous titania thin film can be doped with high concentrations of Eu3+ (up to 8 mol %) to create a bright red photoluminescent material (see picture). The photoluminescence arises from energy transfer through excitation of the titania nanocrystallites in their band gap to the crystal field states of the europium ions; photoluminescence concentration quenching is prevented because of the high surface area and nanocrystalline structure of the material.