This study utilizes three methods, magnetron sputtering deposition (MSD), plasma ion implantation (PIII), and metal vapor vacuum arc (MeVVA), to prepare a thin-film TiO2. The formation of stoichiometrical TiO2-polymorphs as a layer is regularly relevant to the characteristic of the photo-catalytic effect. TiO2-polymorphs created at the outermost surface and initiated by efficient photons are still capable to produce superficial hydroxyl groups for subsequent photo-catalytic reactions. The MSD-treated surface with the majority of TiO2-anatase (101) surface is presently photo-catalytic. The PIII or MeVVA treatment results in an ion-implanted layer of different Ti/O ratios along with the detecting depths, whereas the Ti and 0 elements in TiO2 phase at the outermost surface of the layer can be distinguished. Although the PIII- or MeVVA-treated surface is relatively insignificant in photo-catalytic reactions assessed by water droplet contact angle, the consumption of methylene blue in water and antibacterial test, it is still potential to adjust their surface chemistry by improving the quality of the ion-implanted layer, roughening the contact surface area, and increasing the efficiency to regenerate the photo-catalytic reactions. In addition, the ion implantation methods do not alter the size and dimension of a substrate that is a great advantage to employ them for various advanced applications. (c) 2005 Elsevier B.V. All rights reserved.