In this work, a modified hydrothermal method has been developed and employed for synthesis of nanostructured MoS2 particles. The modification denotes to some changes which were applied with respect to the normal hydrothermal method. Using of a surface-active agent, changing in raw materials and reaction temperature were the main changes which were applied in the modified method with respect to the orginal procedure. Several tools of investigation including XRD, TEM, SEM, and EDXA were used in order to characterize the products and also comparison of the two methods. The results showed a morphology best known as "rag" morphology for the products obtained by both of the methods. In both methods, XRD studies confirmed a semicrystalline state for the particles with slightly lower degree of crystallinity for the modified method. Particle sizes were detected to be in smaller and more uniform state in size and shape for the modified procedure as showed by SEM. Photo-catalytic activity of the particles was checked as MoS2/TiO2 hybrids in photo-oxidative removal of phenol as a selected organic compound. Results showed and enhanced photo-catalytic activity for the hybrids with respect to the pure TiO2 under UV irradiation. MoS2 nanoparticles also verified to have an enhancement effect on the photo-catalytic activity of TiO2 under illumination of visible light. (C) 2007 Elsevier B.V. All rights reserved.