Anomalous enhancement of corrosion resistance and antibacterial property of commercially pure Titanium (CP-Ti) with nanoscale rutile titania film

We report an anomalous enhancement of corrosion resistance and antibacterial property of CP-Ti surface in the presence of a uniform defect-free nanoscale (∼15 nm) rutile titania film. Selective absorption of blue light (∼410 nm) due to matching photon energy with the film band gap, drastically enhanced the electron-hole pair generation, recombination time and the photocatalytic activity. The corrosion resistance of the rutile phase titania films is found to be better than the amorphous films and strongly dependent on the film thickness and surface morphology. The impedance data accounts well for the dual layer structure with an outer barrier titania and inner substochiometric oxide layer.