Electrodeposition of TiO2 Thin Film by Anodic Formation of Titanate/Benzoquinone Hybrid

Electrodeposition of Inorganic/Organic Hybrid Thin Films

“…The overpotential for the same current density was reduced by more than 1 V and it did not increase so much even when the film grew thick. [164] Hydroquinone not only acts as a proton supplier but also its oxidation product hybridizes with titanate as confirmed from the UV absorption spectrum of the ammonia solution dissolving the film (Fig. 20).…”

“…The overpotential during the galvanostatic electrolysis rapidly increased as the film grew thicker. [164] The film was amorphous Ti IV hydroxide. Then, we employed p-hydroquinone as additive to the deposition bath because its oxidation to release protons is thermodynamically more feasible and kinetically faster than the oxidation of water.…”

“…Thin films of metal oxides that are typically electrically insulating can be obtained by means of anodic hybrid electrodeposition with benzoquinone. [164] Electrodeposition of TiO 2 thin films has been tried by several different approaches because of the usefulness of the material. Kavan et al have proposed anodic oxidation of Ti III to deposit Ti IV species from an aqueous solution of TiCl 3 , [165] while Natarajan et al have employed cathodic reduction of nitrate ions in an acidic solution of Ti IV peroxo complex to precipitate Ti IV species by pH change.…”

Electrodeposition of Semiconductors

“…Micro-and nanostructured TiO 2 thick films were prepared in H 2 SO 4 -H 2 O 2 -H 3 PO 4 -HF solution by anodization at low voltages (10-50 V range) by varying the anodization time [168]. Titanium dioxide thin films were electrodeposited from a basic aqueous solution of titanate stabilized by (CH 3 ) 4 N þ cation and containing hydroquinone [169]. Proton formation by oxidation of hydroquinone to benzoquinone promoted precipitation of Ti(IV) species at the anode [169].…”

“…Titanium dioxide thin films were electrodeposited from a basic aqueous solution of titanate stabilized by (CH 3 ) 4 N þ cation and containing hydroquinone [169]. Proton formation by oxidation of hydroquinone to benzoquinone promoted precipitation of Ti(IV) species at the anode [169]. Finally, a dispersion of Degussa P-25 particles in 2-methoxyethanol was used to deposit porous thin layers of nanocolloidal TiO 2 films on TCO substrate [170].…”