Iron-doped titania powders prepared by a sol-gel method. II: Photocatalytic Properties

J.A. NAVÍO; J.J. TESTA; P. DJEDJEIAN; J.R. PADRÓN; D. RODRÍGUEZ; M.I. LITTER

APPLIED CATALYSIS A-GENERAL

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 1999 vol. 178 p. 191 - 203

0926-860X

Samples of iron-doped titania containing different amounts of Fe (0.5±5 wt%) prepared from TiCl4 and Fe(III) acetylacetonate by a sol±gel method were tested as photocatalysts under near-UV irradiation for EDTA oxidation and for Cr(VI) reduction. Their ef®ciency has been compared with specimens prepared by impregnation of TiO2 (Degussa P-25) with iron nitrate or iron acetylacetonate and found to be less active in both redox systems, in spite of the favorable structural properties. The preservation of the P-25 structure in samples prepared by impregnation and a larger amount of defects provided by the preparation technique, acting as recombination centers, seem to be the most important factors affecting the activity. The addition of EDTA highly increases the rate of Cr(VI) reduction, the in¯uence being remarkable in all iron-doped samples.