Electrochemically assisted deposition of titanium dioxide on aluminium cathodes

Adherent, uniform, and porous TiO2 films have been obtained at ambient temperature by a novel electrochemical process involving the simultaneous cathodic electrodeposition of a Ti(IV)-peroxo complex and electrophoretic deposition of nanocrystalline TiO2 particles on an Al cathode. Electrodepositions were performed using an electrolytic suspension containing a water-soluble titanium complex stabilized with a peroxo ligand and a commercial nanocrystalline TiO2 powder (Degussa P25), and by applying a constant cell voltage between 2.0 and 4.5 V. The reduction process favours the decomposition of the soluble titanium complex to yield an amorphous TiO2 precipitate on the cathode. This amorphous precipitate also acts as a binder to the nanocrystalline TiO2 particles. The whole assembly shows photocatalytic activity for the degradation of salicylic acid without the need of thermal post-treatment.