Abstract—Titanium oxide films with different morphologies have for the first time been fabricated through hydrothermal reactions between a titanium substrate and iodine powder in water or ethanol. SEM revealed that iodine supported titanium (Ti-I 2 ) surface shows different morphologies with variable treatment conditions. The mean surface roughness (R a ) was increased in the different groups. Use of surfactant has a role to increase the roughness of the film. The surface roughness was in the range of 0.15 μm-0.42 μm. Furthermore, the electrochemical examinations showed that the Ti-I 2 surface fabricated in alcoholic medium has high corrosion resistance than in aqueous medium. Keywords—Corrosion, Hydrothermal, Surface roughness, Titanium oxide. I. INTRODUCTION ITANIUM and its alloys have become the premier choice for biocompatible dental and orthopedic implant materials [1], [2]. Chemistry and topography of the implant surface mainly influence the biocompatibility, implant-bone integration and long-term stability of the implant. The metallic titanium surfaces are covered by a very thin native oxide films (3-8 nm) on exposure of the metal to air [3], [4]. Titanium oxide thin films show attractive properties, such as chemical durability, biocompatibility and photo response. Thick TiO 2 films can be obtained by oxidation of titanium metal using oxidants or under anodization. Also, numerous approaches the sol-gel, sputtering, chemical solution methods, solvothermal method etc. [5] have often been used as methods for fabrication of TiO 2 thin film in order to change the implant surface topography or chemically modifying the surface layer creating optimized surface layers for different applications. Surface properties, including micro-topography, chemistry and wettability are important factors affecting the quality of bone healing by influencing the biological responses of bone-interfacing implants [6]-[10]. Furthermore, the surface M. P. Neupane, T. S. N. Sankara Narayanan, J. E. Park, Y. K. Kim, and T. S. Bae are with Department of Dental Biomaterials and Institute of Oral Bioscience, Brain Korea 21 Project, School of Dentistry, Chonbuk National University, Jeonju, South Korea (phone: +82-63-270-4040; fax: +82-63-270-4040; email: neumadhav@yahoo.com, tsnsn@reddiffmail.com pje312@naver.com, yk0830@naver.com, bts@jbnu.ac.kr) K. Y. Song is with Department of Prosthodontics, School of Dentistry, Chonbuk National University, Jeonju, South Korea (phone: +82-63-250-2024; fax: +82-63-250-2218; email: skydent@jbnu.ac.kr) M. H. Lee, I. S. Park corresponding authors are with Department of Dental Biomaterials and Institute of Oral Bioscience, Brain Korea 21 Project, School of Dentistry, Chonbuk National University, Jeonju, South Korea (phone: +82-63-270-4040; fax: +82-63-270-4040; email: mh@jbnu.ac.kr ,ilsong@jbnu.ac.kr ) roughness, corrosion resistance and antibacterial properties of the material surfaces are very important factors for the biocompatibility and long-term durability of the implant. Corrosion adversely affects the biocompatibility of a material due to the toxic effect of the corrosion product [11]. If the corrosion resistance is high, the release rate of metallic ions is low. Therefore, it is important to evaluate the corrosion resistance and hence the electrochemical behavior of the metallic material when used in biomaterial applications. Bren et al [12] work confirms that surfaces with nano-scale roughness have greater influence over osteoblast differentiation than micro-scale roughness. Keller et al [13] showed that osteoblast attachment to titanium is directly related to surface roughness. Here we report for the first time that TiO 2 films with different morphologies can be grown through hydrothermal reactions between titanium substrate and iodine powder in aqueous or alcoholic medium with/without any organic templates. The surface properties and corrosion resistance of the different surfaces were evaluated. II. MATERIALS AND METHODS Commercially pure Ti plates grade 2 (20 mm × 10 mm × 2 mm) were abraded with 220 to 800 grits SiC paper and chemically pickled with a mixture of HNO 3 , HF and water in the ratio1:3:6 by volume, respectively. Prepared specimens were hydrothermally heated at 200ºC for 2 h with iodine powder in water or ethanol with/without the aid of surfactants. Oxides films were grown under different conditions, addition of 2% I 2 (1) aqueous solution, (2) ethanolic solution, (3) aqueous solution with 1 g cetyltrimethylammonium bromide (CTAB), (4) ethanolic solution with 1 g CTAB, (5) aqueous solution with 1 g sodium bis(2-ethylhexyl) sulfosuccinate (NaAOT) and (6) ethanolic solution with 1 g NaAOT, respectively. The morphology of the resulting films was investigated by a scanning electron microscopy (SEM). The crystalline structure of films grown in different media was identified by X-ray diffraction (XRD, Rigaku, Japan). The surface roughness of the specimens was quantified using a Surftest Formtracer (Surftest SV-402, Mitutoyo Instruments, Tokyo, Japan). A 2 μm diamond stylus was used to determine the center line average roughness (R a ) along a length of 10 mm. Three individual measurements, between which the distance was 200 μm, were made for each specimen to obtain accurate data regarding the surface roughness. The potentiodynamic polarization behavior of specimens was recorded in the scanning range of - 0.1 to + 0.5 V (vs. Ag/AgCl, KCl satd) at a scanning rate of 2 mV/s. All electrodes were immersed into the Hanks Balanced Salt M. P. Neupane, T. S. N. Sankara Narayanan, J. E. Park, Y. K. Kim, I. S. Park, K. Y. Song, T. S. Bae, and M. H. Lee Hydrothermal Fabrication of Iodine Doped Titanium Oxide Films on Ti Substrate T World Academy of Science, Engineering and Technology International Journal of Biomedical and Biological Engineering Vol:6, No:10, 2012 502 International Scholarly and Scientific Research & Innovation 6(10) 2012 ISNI:0000000091950263 Open Science Index, Biomedical and Biological Engineering Vol:6, No:10, 2012 publications.waset.org/11577/pdf