Electrochemically assisted deposition of titanium dioxide on aluminium cathodes

Abstract

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.