Functional modification of TC4 by Cu-containing titanium dioxide films

To improve the biological fouling and corrosion resistance of Ti6Al4V (TC4) in marine environments, copper-containing titanium dioxide (TiO 2 (Cu)) films were prepared by magnetron sputtering TiO 2 (Cu) powder targets. The morphologies of the films showed that they became rough and coarse from 1.6 nm of the TiO 2 film to approximately 9 nm of the TiO 2 (Cu) films, which might be owing to the increase in the deposition rates from 1.33 to 2.08 nm/min. No diffraction orientations of the TiO 2 and Cu phases were found compared to those of the TiO 2 (Cu) powder. Ti, O, and Cu were detected using X-ray photoelectron spectroscopy to confirm the composition of the films. The ratio of Cu 2+ increased as the Cu content of the films increased, whereas that of Cu/Cu  +  scarcely changed. The TiO 2 and TiO 2 (Cu) films exhibited photocatalytic effects and their photocatalytic intensities decreased as the Cu content increased. Hydrophobicity was enhanced by the addition of Cu to the film. The antibiological fouling effect of the TiO 2 (Cu) films remained unchanged as the Cu/Ti ratio varied. Compared with those of TC4 , the corrosion current densities of the TiO 2 (Cu) films decreased by one order of magnitude and the corrosion potentials increased by 350 mV in artificial seawater , indicating that the corrosion resistance of TiO 2 (Cu)/TC4 was improved. Importantly, Cu was in abundance in the films for both antibiological and corrosion resistance functions owing to the saturated ratio of Cu/Cu + irrespective of the Cu/Ti ratio in the films.