Sn-doped and undoped nano-TiO3 particles have been synthesized by hydrotermal process without solvent at 200 degrees C in 1 h. Nanostructure-TiO2 based thin films have been prepared on glass substrate by spin-coating technique. The structure, surface morphology and optical properties of the thin films and the particles have been investigated by element analysis and XRD, SEM, BET and UV-vis-NIR techniques. The photocatalytic performance of the films were tested for degradation of Malachite Green dye in solution under UV and vis-lights. The results showed that (a) hydrothermally synthesized nano-TiO, particles are fully anatase crystalline form and are easily dispersed in water, (b) the coated surfaces have nearly super-hydrophilic properties and, (c) the doping of transition metal ion efficiently improved the photocatalytic performance of the TiO2 thin film. (c) 2006 Elsevier B.V All rights reserved.