抄録
Porous and nanostructured TiO2 films have been developed for photocatalysts and dye-sensitized solar cells with high performance due to large surface area of the films. For the high performance, the film requires increasing the film thickness as well as specific surface area. Nanoporous and thick TiO2 films with large surface area were successfully prepared onto a glass substrate by a dip-coating technique. The dip-coating solutions containing colloidal TiO2 nanoparticles were prepared by hydrolyzing titanium(IV) isopropoxide and adding trehalose. The films calcined at 500 °C were uniform and transparent. The films were aggregates of TiO2 nanoparticles and interstices between the particles are significantly existing. The maximum thickness of the film prepared by one-run dip-coating was ca. 740 nm. Our method can be controlled the porosity of TiO2 films in the range of 30 to 56% by changing trehalose concentration in the dip-coating solution.
