from first principles PP-I-1

PP-V-8Production of Highly Active Doped Titania Photocatalysts by AqueousSol-Gel Processing - Synthesis and Characterization of the XerogelsMalengreaux C.M. 1 , Léonard G. 1 , Heinrichs B. 1 , Bartlett J.R. 21 Laboratoire de Génie Chimique, B6a, Université de Liège, B-4000 Liège, Belgium2 School of Natural Sciences, University of Western Sydney, Penrith South DC, NSW 1797,AustraliaCharline.Malengreaux@ulg.ac.beEnvironmental pollution has become a critical issue for modern society and numerous studiesinvolving semiconductor-mediated heterogeneous photocatalysis have been carried out todevelop materials for the purification of air and water under natural or artificial-lightillumination [1]. In our research, an environmentally-friendly aqueous sol-gel process wasdeveloped to produce anatase photocatalysts doped with Fe 3+ in order to be able to activatethe photocatalysts with visible light. The physicochemical properties of the xerogels werecharacterized by ICP-AES, XRD, UV-Vis spectroscopy and N 2 adsorption-desorption. Thephotocatalytic activity of the pure and doped photocatalysts was evaluated by monitoring thedegradation of p-nitrophenol under visible light using a home-made installation [2].The results showed that the dopant was successfully incorporated into the TiO 2 photocatalystswith a high precision and reproducibility. XRD measurements established that allphotocatalysts are constituted of TiO 2 -anatase after drying at room temperature and it wasalso found that the optical properties, especially the value of the band-gap E g , of the catalystsdecreased when increasing the dopant content in the TiO 2 matrix. The textural properties ofthe photocatalyst were measured and it has been observed that the materials are purelymicroporous and presents a high specific surface area, S BET , which slowly decreases whenincreasing the dopant content. The photocatalytic activity measured under visible light forPure-TiO 2 produced by this aqueous sol-gel process was remarkably high for a non-calcinedmaterial. In the case of doped TiO 2 , the evolution of the activity with the dopant content hasbeen studied and an optimal dopant content value has been determined.References:[1] A. Fujishima, X. Zhang, D.A. Tryk, Int J Hydrog Energy, 32 (2007) 2664-2672.[2] L. Tasseroul, S.L. Pirard, S.D. Lambert, C.A. Páez, D. Poelman, J.-P. Pirard, B. Heinrichs, ChemEng J (2012) Article in press.317