A facile one-step anodization treatment to prepare multi-level porous titania layer on titanium

In order to fabricate micron-scale and submicron-scale porous morphologies on titanium implants more facilely, a one-step anodization treatment was developed. Through anodic oxidation in 1 M CH3COONa electrolyte in the step-galvanostatic mode, a crystalline titania layer with multi-level porous morphology was prepared on titanium substrate. The multi-level porous morphology consisted of micron-sized craters (2–20 μm) overlaid with densely distributed submicron pores (50–500 nm). The formation process of the multi-level porous structure was investigated and the possible mechanism was discussed. It can be concluded that both the CH3COONa electrolyte and the step-galvanostatic mode contributed to its formation. In addition, the development of craters was ascribed to gradual field-assisted dissolution by CH3COO− anions and submicron pores were generated by spark discharges.

► A one-step anodization treatment to fabricate multi-level porous titania layer.
► The titania layer consisted of micron craters overlaid with submicron pores.
► A schematic illustration of the formation mechanism was proposed.