Wastewater purification using nanotubular TiO2 films obtained by anodic oxidation: a comparison with VOC degradation

The immobilization of nanostructured photocatalysts is of great importance in the purification of both liquids (e.g. industrial wastewaters) and polluted air. Titanium dioxide films with nanotubular morphology and good photocatalytic efficiency in both environments can be produced by anodic oxidation, which avoids release of nanoscale materials in the environment. Here we evaluate different oxidation processes in order to identify the most efficient and robust technology for the production of TiO2 layers with high specific surface area. The role of the electrolyte in particular is crucial: nanoporous or nanotubular structures show different activities in liquid or gas phase degradation reactions, and within nanotubular structures a large variable is represented by the electrolyte, which influences both overall activity and treatment robustness.