Nanocrystalline titanias were obtained by thermal reaction of titanium tetraisopropoxide in 1,4-butanediol (glycothermal reaction). In this study, titanias modified with various elements (B, Mg, Al, P, Zn, and Ga) were prepared by the glycothermal method. The obtained samples were nitrified and their physical and photocatalytic properties were investigated. Among the six modifiers examined, addition of P was the most effective for photocatalytic decomposition of acetaldehyde under visible-light irradiation. After nitrification and annealing, the P-modified Titania showed a strong absorption in the visible region (400-550 nm). It was found that the photocatalytic activity was related to the amount of nitrogen atoms doped in the anatase structure. (c) 2006 Elsevier B.V. All rights reserved.