Nanostructured iron(III) oxides: From design to gas- and liquid-phase photo-catalytic applications

The development of sunlight-activated and environmentally friendly photo-catalysts for wastewater treatment and air purification is an open scientific and technological challenge. In this regard, the present work reports on a Chemical Vapor Deposition route to phase-pure iron(III) oxide nanosystems [α-Fe2O3 (hematite) and β-Fe2O3 (bixbyite)]. The obtained polymorphs have been characterized in detail in their nanostructure, composition, morphology and optical properties. The synthesized supported Fe2O3 nanomaterials have also been tested in the photo-degradation of a model organic dye (methylene blue) in the liquid phase, as well as in the photo-oxidation of NO in air, both activated by simulated solar light. The obtained results, of interest for eventual use in water and air purification, are critically discussed as a function of nanosystem chemico-physical properties.