Organic photocatalysts for the oxidation of pollutants and model compounds

Abstract

The use of organic photocatalysts for the oxidation of pollutants and model compounds, with special emphasis on the involved concepts and mechanistic aspects, is reviewed. Photoinduced electron transfer involving the singlet excited state of phthalocyanines has been postulated in the photodegradation of phenols. The reactivity of OH - radical with different pollutants has been quantitatively determined by competition experiments, looking at the decrease of the typical transient absorption of the stilbene adduct at 390 nm. As regards heterogeneous media, after excitation at 355 nm of phthalocyanines immobilized in zeolites, the characteristic singlet oxygen luminiscence is monitored at 1270 nm. TPP has been included within extralarge pore zeolitic aluminosilicates, such as MCM-41. These materials provide an adequate balance between moderate cage effect and facilitation of molecular traffic through the mesopores.