Synthesis of porous titania thin films using carbonatation reaction and its hydrophilic property

Super-hydrophilic porous titania thin films containing mesoscale channels were successfully synthesized by the carbonatation reaction. An amorphous Li-Ti-O film with a smooth surface was prepared on a glass substrate by radio frequency magnetron sputtering using a Li₂TiO₃ target in an Ar atmosphere. The as-deposited films were carbonated at 400 °C for 10 h in CO₂, resulting in the formation of Li₂CO₃ and the development of characteristic through-channels. After dissolution of the Li₂CO₃ in distilled water, porous TiO₂ thin films with mesoscale through-channels were fabricated. The obtained porous films had a large surface area and show a rapid decrease in the water contact angle or excellent super-hydrophilicity.