Electrochemical impedance spectroscopy study of the passive oxide film on titanium for implant application

✍ Scribed by J. Pan; D. Thierry; C. Leygraf

• Publisher: Elsevier Science
• Year: 1996
• Tongue: English
• Weight: 897 KB
• Volume: 41
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(95)00465-3

✦ Synopsis

The surface oxide film on titanium and its long-term stability in biological environments play a decisive role for the biocompatibility of titanium implants. In this study, the passive oxide film formed on titanium and its natural growth in a phosphate buffered solution with and without an H,O, addition have been investigated by electrochemical impedance spectroscopy (EIS) measurements over a period of several weeks. In the absence of H,O,, the impedance response indicated a stable thin oxide film on titanium. However, the introduction of H,O, into the solution resulted in significant changes in the EIS-spectra, which varied with exposure time. The interpretation of results is based upon a two-layer model of the oxide film, consisting of a thin barrier-type inner layer and a porous outer layer. The H,O, addition in the solution led to a significant decrease in corrosion resistance of titanium and also to a thickening of the porous outer layer. The observations may provide an explanation of the unexpected in uivo titanium oxide growth and ion incorporation into titanium implant oxide surfaces.