Semiconducting Properties of Anodic Oxide Films Grown on Titanium in Ringer and PBS Solutions

In the present study investigations of semiconducting properties of anodic oxide films formed on titanium were carried out. Oxide films were produced by using potentiostatic anodization of the metal in two solutions: PBS solution with pH = 8.9 and Ringer solution with pH = 7.8. In order to analyze the properties of the obtained films, Electrochemical Impedance Spectroscopy (EIS) was applied. To characterize the surface morphology Scanning Electron Microscopy (SEM) was used. From the results of this study the following properties of the titanium dioxide films were determined: a density of charge carriers and a flat band potential. To derive these parameters Mott-Schottky dependence was applied. Donor densities were found to be of the order of 1020 carriers per cm3. In turn, average flat band potentials are found to be -0.736 V vs. SCE in Ringer solution and -0.784 V vs. SCE in PBS solution.